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Escuela de Especialidades “Antonio de Escaño”

INGLÉS TÉCNICO MARÍTIMO

Impreso en el Centro de Ayudas a la Enseñanza de la Armada

PE-IDM.601(B)

EE “Antonio de Escaño” Departamento de Idiomas

INGLÉS TÉCNICO-MARÍTIMO

CONTENTS CHAPTER 1.-

BOILERS

CHAPTER 2.-

RECIPROCATING STEAM ENGINE

CHAPTER 3.-

INTERNAL COMBUSTION ENGINE

CHAPTER 4.-

LINE OF SHAFTING. CRANKSHAFT. PROPELLER

CHAPTER 5.-

TURBINES.TYPES

CHAPTER 6.-

AUXILIARY MACHINES

CHAPTER 7.-

PUMPS

CHAPTER 8.-

CONDENSERS & EVAPORATORS

CHAPTER 9.-

VALVES

CHAPTER 10.-

COMBUSTIBLES & LUBRICANTS

CHAPTER 11.-

MEASURES. UNITS. INSTRUMENTS

CHAPTER 12.-

METALLURGY´S NOMENCLATURE. METAL´S TOOLS

CHAPTER 13.-

ELECTRICITY

CHAPTER 14.-

ELECTRIC ENGINES

CHAPTER 15.-

DAMAGES. NOMENCLATURE

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PE-IDM.601(B)

EE “Antonio de Escaño” Departamento de Idiomas

INGLÉS TÉCNICO-MARÍTIMO

CHAPTER 1 BOILERS Vocabulary Air cock. Air draught Ashpit Ashpit door Automatic feed water regulator Auxiliary boiler Auxiliary steam valve Auxiliary feed check valve Blow down cock Blow down valve Blowers Boiler Boiler feed water Boiler furnace. Boiler mountings Boiler shell Boiler stays Boiler stop valve Bridge Burners. Casing. Combustion chamber. Cyclone steam separator Cylindrical boiler Direct flame boiler. Double ended boiler. Dome. Downcomer tubes Drain cock Economiser Feed check valve. Feed water. Fire bars. Fire tube boiler. Fire bridge.

Grifo atmosférico. Tiro de aire. Cenicero. Puerta de cenicero. Regulador de alimentación. Caldera auxiliar. Válvula auxiliar de vapor. Válvula de retención auxiliar. Grifo de extracción de fondo. Válvula de extracción de fondo. Sopladores. Caldera. Agua de alimentación caldera. Horno de la caldera. Accesorios de las calderas. Envolvente de la caldera Tirantes de la caldera Válvula de comunicación de la caldera Altar. Quemadores. Envolvente. Cámara de combustión. Separador del vapor ciclón. Caldera cilíndrica. Caldera de llama directa. Caldera de doble frente. Domo. Tubos descendentes. Grifo de purga. Economizador. Válvula de alimentación. Agua de alimentación. Parrillas. Caldera tubular o fumitubular. Altar del hogar. 3

PE-IDM.601(B)

EE “Antonio de Escaño” Departamento de Idiomas

INGLÉS TÉCNICO-MARÍTIMO Vocabulary Forced draught. Fuel burners. Furnace. Furnace door. Gauge glass. Generator tubes. Grate. Header. High pressure boiler. Iner casing. Low pressure boiler Main boiler. Main feed check valve. Main steam top valve. Manhole door. Natural draught. Nest tube. Outer casing. Pressure gauge. Reheater. Return flame boiler. Safety valve. Saturated furnace. Saturated steam. Scotch boiler. Side water wall tubes. Smoke box. Smoke tube boiler. Soot blowers. Stay. Stay tube. Steam cock. Steam pressure gauge Steam drum. Stop valve. Superheat furmace. Superheat steam. Superheater. Superheater tubes. PE-IDM.601(B)

Tiro forzado. Quemadores de combustible. Horno. Puerta del horno. Tubo indicador de nivel. Tubos generadores. Parrilla. Cabezal. Caldera de alta presión. Envoltura interior. Caldera de baja presión. Caldera principal. Válvula de retención principal. Válvula de comunicación. Puerta de registro. Tiro natural. Haz tubular. Envoltura exterior. Manómetro. Recalentador. Caldera de llama de retorno. Válvula de seguridad. Hogar del vapor recalentado. Vapor saturado. Caldera escocesa. Pared lateral de tubos refrigerados. Caja de humos. Caldera fumitubular. Sopladores de hollín. Estay, virotillo. Tubo estay. Grifo de vapor. Manómetro. Colector de vapor. Válvula de comunicación. Horno de vapor recalentado. Vapor recalentado. Recalentador. Tubos de recalentado. 4

EE “Antonio de Escaño” Departamento de Idiomas

INGLÉS TÉCNICO-MARÍTIMO

Three-drum boiler. Up-take. Water drum. Water gauge. Water tube boiler. Water wall header. Water wall tubes. Working pressure.

Caldera de tres colectores. Conducto de humos. Colector de agua. Indicador de nivel. Caldera acuotubular. Cabezal de la pared de agua. Pared de agua. Presión de trabajo.

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PE-IDM.601(B)

EE “Antonio de Escaño” Departamento de Idiomas

INGLÉS TÉCNICO-MARÍTIMO BOILER

A boiler is a container that is capable of generating steam by the internal or external application of heat. MAIN TYPES OF BOILERS There are two general classes of boilers: The smoke tube boiler and the water tube boiler. In the smoke tube boiler, the smoke gases pass through the tubes which are inmersed in water, and in the water tube boiler, the water passes through the tubes which are surrounded by gases. SMOKE TUBE BOILER The most common type of boiler, among the smoke tube boilers is the “Scotch boiler”. This boiler has a cylindrical steel shell; the ends of this shell are called the front end and back end. Front end has three or four openings into which the furnaces are fitted. The furnaces are divided into two parts, the upper part for the fire and gases and the lower part for the ashpit. The water inside the boiler should be kept to a level above the top of the tubes. The hot gases pass from the furnace to the combustion chamber in the back of the boiler, and from there through the tubes to the smoke box and funnel. The water inside the boiler is converted into steam which is collected at the top of the boiler and from there passes through a stop valve to the engines. To compensate the loss of water there is a feed check valve through which fresh water is pumped into the boiler. WATER TUBE BOILERS In this type, flames and hot gases are outside the tubes and the water circulates through them. The Yarrow boiler is the classic water tube boiler, it consists in two cylindrical drums connected by small tubes to and upper drum which collects the steam. The two cylindrical drums and tubes contain the water, and the steam goes to the engine through a steam stop valve situated in the upper drum. The water tube boilers have the advantage over the fire tube boilers in that the steam may be generated more quickly, and the weight of the boiler and the contained waters is loss, and also is less danger of explosions. Nowadays, water tube boilers are provided with superheaters economisers. The superheat is usually located between the rows of water tubes. As the superheat steam temperature tends to fluctuate with the rate of steaming of the boiler and causes loss of engine efficiency, controlled superheat boilers have been developed, as the Babcock Wilcox D-shaped boiler in which the steam drum is mounted vertically over the single water drum, and is interconected by water tubes. PE-IDM.601(B)

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EE “Antonio de Escaño” Departamento de Idiomas

INGLÉS TÉCNICO-MARÍTIMO

A tranverse baffle, formed by a set of large tubes divides the tubes in a front pass and rear pass. A single superheater is used and its tubes are set between the fire rows and generator rows of the front pass. Dampers are fitted at the base of the uptake over each pass, and the volume of furnace gases can be varied operation of the dampers. The furnace is formed by a row of “water wall” tubes terminating in a side water header. An economiser is fitted in the uptake above the dampers. BOILERS MOUNTINGS The main fittings in a boiler are: 1. Safety valve to prevent any excess of pressure in the boiler. 2. Feed check valve to admit the water into the boiler in conjunction with an automatic feed regulator. All boilers are to be provided with two feed check valves connected to separate to separate feed lines. 3. Blow down valve to empty the boiler, blowing the water out to sea. Each boiler is to be fitted at least with one blow down valve secured direct to the lower part of the boiler. 4. Main steam stop valve to control the passage of steam from the boiler to the engines. Every boiler is to be fitted with one main stop valve secured direct to the shell. 5. Air cocks to release air when raising steam. 6. Steam pressure gauge to indicate the pressure of the steam inside the boiler. The gauges are to be placed where they are easily seen. 7. Water gauge to indicate the high of water inside the boiler. Every boilers is fitted with at least two independent means of indicating the water level in it, one of which is to be a glass gauge.

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PE-IDM.601(B)

EE “Antonio de Escaño” Departamento de Idiomas

INGLÉS TÉCNICO-MARÍTIMO

PE-IDM.601(B)

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EE “Antonio de Escaño” Departamento de Idiomas

INGLÉS TÉCNICO-MARÍTIMO

TWIN FURNACE

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PE-IDM.601(B)

EE “Antonio de Escaño” Departamento de Idiomas

INGLÉS TÉCNICO-MARÍTIMO

CHAPTER 2 RECIPROCATING STEAM ENGINE Vocabulary Air pump Bed plate Brasses Compound engine Condenser Connecting rod Crankpin Crosshead Cylinder cover Cylinder barrel Cylinder bottom Cylinder liner Cylinder ring Cylinder bore Drain cocks Eccentric sheave Eccentric strap Engine columns Gland Governor Guide shoe High pressure cylinder Intermediate pressure cylinder Low pressure cylinder Piston Piston rod Quadruple expansion Relief valve Shafting Slide valve chest Slide valve Sluice valve Stop choke valve Stuffing box Triple expansion engine

Bomba de aire Bancada Metal antifricción Máquina compound Condensador Biela Muñón del cigüeñal Cruceta Tapa del cilindro Cuerpo del cilindro Fondo del cilindro Camisa del cilindro Anillo del cilindro Diámetro interior del cilindro Grifos de purga Platillo de excéntrica Collar de excéntrica Columnas de la máquina Corona o manguito de prensaestopas Regulador Patín de cruceta Cilindro de alta presión Cilindro de media Cilindro de baja presión Émbolo Vástago Máquina de cuádruple expansión Válvula de seguridad Ejes Caja de distribución Válvula distribuidora Válvula de corredera Válvula de retención Caja de prensaestopas Máquina de triple expansión

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PE-IDM.601(B)

EE “Antonio de Escaño” Departamento de Idiomas

INGLÉS TÉCNICO-MARÍTIMO ENGINE

An engine is a machine for applying mechanical power, and so, converting energy into motion. The principal types used for ship propulsion are: Reciprocating steam engine Steam turbine Internal combustion engine RECIPROCATING STEAM ENGINE The reciprocating steam engine uses the steam in succession through two, three or more different cylinders, and they may be classified as: Compound engine Triple expansion engine Quadruple expansion engine Gas turbine The steam passes through the boiler stop valve to the engine THE COMPOUND ENGINE The compound engine is used for propulsion of small vessels, or in auxiliary engine. It has two cylinders: the high pressure cylinder and the low pressure cylinder. The steam passes through the boiler stop valve to the engine stop valve and then successively entering in the high pressure cylinder and low pressure cylinder, through their slide valves, working on the piston of each cylinder as it expands. When the steam leaves the low pressure cylinder then passes to the condenser, and is converted into water by coming into contact with cold pipes and by means of the air pump, the water pass into a feed tank and from thence into the boiler again. TRIPLE EXPANSION ENGINE The triple expansion engine has three cylinder: high pressure, first intermediate pressure and low pressure cylinder. Steam from the boilers is admitted to the high pressure cylinder then passes to the intermediate pressure cylinder, and finally to the low pressure cylinder and condenser. This type of engine is very common in old merchant ships, and the boiler for this engine has a pressure between 180 to 220 psi square. QUADRUPLE EXPANSION ENGINE The quadruple expansion engine has four cylinders: high pressure, first intermediate pressure, second intermediate pressure and low pressure cylinder. As the volume of steam increases as the pressure decreases each succesive cylinder is larger in diameter and works at lower pressure than the preceding one. PE-IDM.601(B)

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EE “Antonio de Escaño” Departamento de Idiomas

INGLÉS TÉCNICO-MARÍTIMO

PARTS OF THE ENGINE The main parts of the engine are: Cylinders and their connections Shafting Bedplate Auxiliary fittings CYLINDER The cylinder is the part of the reciprocating engine in which the steam acts to force the piston from one end to the other and viceversa. It is made of cast iron. The inner surface of the cylinder is formed by a liner. The piston is attached to the piston rod and this one to the connecting rod which fits to the crankpin. The upper part of the cylinder is called cylinder head and is attached to the barrel by means of stud and nuts. The lower cover is fitted with a stuffing box and gland to permit the passage of the piston rod but to prevent the scape of steam. The steam is distributed into the cylinder by a slide valve, which is contained in a box or steam chest on one side of the cylinder. This valve is driven from the crankshaft by means of an eccentric. The top and bottom of each cylinder is provided with a relief valve to prevent against undue rise of pressure and also a drain cock is fitted at the bottom of the cylinder.

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PE-IDM.601(B)

EE “Antonio de Escaño” Departamento de Idiomas

INGLÉS TÉCNICO-MARÍTIMO

PE-IDM.601(B)

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EE “Antonio de Escaño” Departamento de Idiomas

INGLÉS TÉCNICO-MARÍTIMO

CHAPTER 3 INTERNAL COMBUSTION ENGINE Vocabulary Air compressor Air inlet valve Air starting valve Bearings Bearing loads Bearing saddles Bedplate Blowers Bridge Cams Camshaft Compression Connecting rod Connecting rod bearing Coupled Cooler Cooling water pipe Crankcase Crankpin Crankshaft Crankweb Crosshead Crosshead bearing Crosshead shoe Cylinder Cylinder block Cylinder head Cylinder liner Exhaust Exhaust manifold Exhaust pipe Exhaust ports Exhaust valve Firing

Compresor de aire Válvula de admisión de aire Válvula de arranque Cojinetes Cargas en cojinetes Soportes de los cojinetes Bancada Sopladores, ventiladores Puente Camones Eje de camones Compresión Biela Cojinete cabeza de biela Acoplado Refrigerador Colector de agua de refrigeración Cárter del cigüeñal Muñequilla del cigüeñal Eje del cigüeñal Guitarra Cruceta Cojinete de cruceta Patín Cilindro Bloque de cilindro Culata Camisa del cilindro Evacuación Colector de escape Tubo de escape Lumbreras de escape Válvula de escape Explosión 15

PE-IDM.601(B)

EE “Antonio de Escaño” Departamento de Idiomas

INGLÉS TÉCNICO-MARÍTIMO Flexible coupling Flywheel Four stroke engine Fuel injection pump Fuel valve Gear-box Gland Inlet Inlet pipe Internal combustion engine Liner Low pressure (L.P.) Lubricating oil pipe Outlet Output Piston Piston crown Piston rings Piston rod Reheater Relieve valve Scavenge pump Scavenging Scavenging air cooler Scavenging air manifold Scavenging ports Silencer Starting valve Stroke Superheat Tie-rods Trunk-piston Two-stroke engine Valve gear Water jacket

PE-IDM.601(B)

Acoplamiento flexible Volante Motor de cuatro tiempos Bomba de inyección Válvula inyectora Caja de engranajes Corona de prensaestopa Admisión Tubo de admisión Motor de combustión interna Camisa Baja presión Tubería de aceite de lubricación Salida Potencia Émbolo Corona del pistón Aros del pistón Vástago Calentador Válvula de seguridad Bomba de barrido Barrido Enfriador de barrido Colector de barrido Lumbreras de barrido Silenciador Válvula de arranque Embolada Sobre-calentar Tirantes Cilindro de tranco Motor de dos tiempos Mecanismo válvula distribuidora Galería de refrigeración de agua

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EE “Antonio de Escaño” Departamento de Idiomas

INGLÉS TÉCNICO-MARÍTIMO

INTERNAL COMBUSTION ENGINE In an internal combustion engine, the power is developed as a result of the combustion of air and fuel. Types of internal combustion engines are the Diesel or Semi-Diesel, which are used as main engines in motor ships, and auxiliary engines in steamships. They may be either of the two-stroke cycle type which gives a power stroke once every revolution, or the four stroke cycle, which gives a power stroke every two revolutions or the four stroke cycle, which gives. In the diesel engine, air is drawn into the cylinder and then compressed by the piston; when the air is compressed fuel is sprayed into the cylinder at a high pressure, and is ignite by the hot air and makes it to expand and drive the piston. The cylinder head has an air inlet valve, a fuel valve and a exhaust valve, and a starting valve. The cylinders, cylinder heads and piston are all water cooled, to prevent cracking due to the high temperature of combustion. The cycles in a four-stroke type are called: Suction Compression Firing Exhaust In the first stroke, when the piston is moving down wards, air goes into the cylinder through the air inlet valve. In the second stroke, the air is compressed while the piston is driven upwards and its temperature reaches 1.200º F. In the third stroke, the fuel valve is opened and sprays fuel into the cylinder, which is ignited and when the gas expands it drives the piston downwards. In the fourth stroke, the piston goes upwards and the burnt gases are driven out through the exhaust valve. TWO STROKE ENGINE The two-stroke engine has much power than the four stroke engine. In the two-stroke engine, one out-stroke and one-in-stroke representing one complete revolution of the crankshaft, completes the cycle. Compression takes place about the beginning of the upward stroke or the piston; at the end of the stroke fuel is inyected and fired. Expansion takes place on the downward stroke until the exhaust ports are uncovered, when air under pressure is admitted.

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PE-IDM.601(B)

EE “Antonio de Escaño” Departamento de Idiomas

INGLÉS TÉCNICO-MARÍTIMO

A popular type of the two-stroke engine is the “British Polar”. The cylinder head has only two valves: starting air valve, and fuel valve. Controlled by the piston are the scavenge air inlet and exhaust valve. To produce starting air are used compressors. The air is stored in large cylinders at about 300 psi square.

PE-IDM.601(B)

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EE “Antonio de Escaño” Departamento de Idiomas

INGLÉS TÉCNICO-MARÍTIMO MOTOR “SULZER”

TURBO-BLOWER

THRUST SHAFT

CONNECTING ROD CRANKSHAFT

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PE-IDM.601(B)

EE “Antonio de Escaño” Departamento de Idiomas

INGLÉS TÉCNICO-MARÍTIMO

Internal Combustion Engines: design details of the Z40 engine The bedplate is made of steel-plate and features forgedbearing saddles welded on to the plate. This permits a relatively light, yet stiff and rugged design. By means of tie-rods, the bedplate and cast cylinder block are placed under compressive stress. The crankshaft is forged from one block and has exceptionally large dimensioned crakpins and shaft diameters, this permits the use of normal carben stuel with good impact values. Furthermore relatively law bearing loads are achieved. This concept assures a high degree of operational safety even under difficult conditions. The maximun pressure reaches only about 120 kp/cm2 at full load, so that white metal-bushed bearings, with their known good operational characteristics can be used special surface treatment of the craknpins is not required. The outputs for shafts admitted by the classification societies are considerably above the nominal outputs. For the crankshafts of a 12-cylinder in-line Z-40 engine, there is for instance, for Lloyd´s Register a reserve of output of 36 per cent. (pme = 13 kp/cm2, p=127 kp/cm2) (bmep = 185 psi2, p=1806 psi2). As is customary on two-stroke engines with modest piston speeds, the crankshaft does not possess counterweights. However in the future, it is planned to fit the Z engines with counterweights to balance about 50 per cent of the rotating masses. This is undertaken with a view to the increasing applications where engines are running at full speed under no load or when they are exposed temporarily to excess speeds, for example on diesel-electric drives of ice-breakers. The characteristics of the bearing load will then also prove more favorable for normal service as well. In the layout of the main crankshaft bearings, the upper bearing cap is placed under compressive stress by means of pressure bolts designed as hydraulic jacks. This design permits convenient erection since the oil pressure needed for pre-stressing is generated outside the engine by means of a pump. By this simple means, the correct compression of the bearing caps and adequate clearance is guaranteed. During operation, the two pressure bolts are used to feed the bearing with lubricating oil, and the piston with cooling oil, thus obviating the necessity of a separate line to the bearing cap. The oil fed to the main bearing reaches the crankpin through inclined holes in the web and thence to the piston through the connecting rod. For reasons of strength the piston is made from forged steel and carries four compression rings. The uppermost ring groove is chromiumplated and fitted with a piston ring having a gas-thight joint. Cooling of the piston crown is effected by oil, as shown in other types.

PE-IDM.601(B)

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EE “Antonio de Escaño” Departamento de Idiomas

INGLÉS TÉCNICO-MARÍTIMO

The fuel injection pumps on the Z-engines are of the helix-controlled type. An individual pump is provided for each cylinder. The pump casing has two separate chambers respectively connected to an inlet and an out-let pipe. Priming is carried out from the upper chamber and the excess fuel not required for injection returns to the lower chamber.

Technical Vocabulary Bearings loads Bearing saddles Bmep (break mean effective pressure) Counterweights Chromiumplated Clearance Compressive stress Erection Carbon steel Full load Groove Gas-thight joint Hydraulic jack Helix Layout Metal-bushed Kp/cm2 Outputs Pme (mean pressure) Steel plate Stiff Stress Thight Tie-rods Welded

Cargas en cojinetes Soportes del cojinete Presión media efectiva Contrapesos Cromado Holgura Carga de compresión Montaje Acero corriente, acero carbono Máxima carga Muesca, ranura Junta estanca al gas Gato hidráulico Espiral Disposición Recubrimiento de metal Kilopondio por cm2. Potencias Presión media efectiva Plancha de acero Rígido Esfuerzo Estanco Tirantes Soldado

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PE-IDM.601(B)

EE “Antonio de Escaño” Departamento de Idiomas

INGLÉS TÉCNICO-MARÍTIMO North-Eastern Reheater Engine

Economy is effected in a reciprocating engine when the steam remains dry through the expansion from H.P. to L.P. the presence of water assists the conduction of heat away from the cylinders, and is undesirable for that reason and also from the point of view of economy, in the amount of make-up water required for the boilers due to leakage. When steam remains dry, very little leakage takes place at the glands. The total make-up required with type of engine is given as about 1,5 tons per 1.000 h.p. Efficiency is increased by using steam at the highest possible temperature at the H.P. end. Not only does the engine gain in efficiency but also, since the heat in the superheated steam has been taken from the funnel gasses, the efficiency of the whole installation is increased. In one installation superheated steam leaves the boliers at 220 psi. square and at 750º F. Now this temperature is too high to permit an efficient lubrication of the H.P. piston-rings and liner. The admission temperature of steam to the H.P. is therefore reduced by passing the high-temperature steam through tubes on the outside of which is the lower-temperature steam on its way from the H.P. exhaust to the M.P. inlet. In this way the temperature of the steam being admitted to the H.P. cylinder is reduced to 600º F and the heat given up by that steam is recovered by the H.P. exhaust steam on its way to the M.P. the admission temperature of the steam to the M.P. which would normally be 425º F is thus raised to 575º F, at the pressure of 70 psi/sq. in gauge, the saturation temperature is 316º F., so that the steam now has 259º F of superheat. This is sufficient to keep the steam dry during subsequent expansion. The fitting employed by which heat leaves the H.P. steam and is picked up by the M.P. steam is called the reheater or exchanger. Its consists of an outer casing with inlet and outlet branches. A tube plate on one end carries about one hundred looped tubes, which are expanded in place. The tube plate is held in place between the flange of the outer casing and the flange of an end cover, which has a division plate and branches for inlet and outlet of the H.P. steam. Baffles are fitted within the tubenest to direct the H.P. exhaust so that it passes over the tubes four times. The reheater is very useful. Lubricating oil is supplied to points in the cylinder lines and piston-rod glands by mechanical lubricators which can be adjusted to give the best results as regards wear of the parts and low oil consumption. Most of this oil is supplied at the H.P. end, because some of the oil finds its way into the other cylinder being carried there by steam. Stephenson valve gear is used to operate the H.P. and M.P. poppet valves, there being four valves per cylinder, two inlet and two exhaust, operated by cams on as oscillating shaft. The valves are returned to their seats by external springs, and are so designed that they rotate very slowly, opening and shutting. This helps to keep the valves in good conditions.

PE-IDM.601(B)

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EE “Antonio de Escaño” Departamento de Idiomas

INGLÉS TÉCNICO-MARÍTIMO

The recorded fuel-oil comsumption for engines of 4.000 i.h.p. is 0.766-0.799 pd/i.h.p./hour. Technical Vocabulary Branches Casing Exhaust Expanded Fitting Flange Gauge Glands H.P. (high pressure) Division plate Inlet Liner L.P. (low pressure) Leakage Make-up M.P. (medium pressure) Piston rings Reheater Outlet Steam Superheat, to Superheated steam Tube nest Tube plate Valve gear

Brazos, ramales, tubos Envolvente Escape, salida Mandrilados Accesorio Brida, platina Indicado, indicador Corona de prensaestopas Alta presión Placa de division Admisión Camisa Baja presión Pérdida Suministrar Presión intermedia Aros del pistón Calentador Salida Vapor Sobrecalentar Vapor recalentado Haz tubular Placa de tubos Mecanismo movimiento válvula distribuidora Camones Válvula distribuidora

Cams Poppet valve

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PE-IDM.601(B)

EE “Antonio de Escaño” Departamento de Idiomas

INGLÉS TÉCNICO-MARÍTIMO P & Diesel Engines

Type 26 MTB-40V is a four-stroke, non reversible, trunk-piston V- engine with exhaust turbocharging and inter-cooling of the charging air. The cylinder bore is 260 mm. and the stroke 400 mm. The cylinders are ranged in two banks forming an angle of 45º to each other, a design that has resulted in a low and compact engine suitable for installation in engine rooms with relatively little headroom. The 26 MTB-40V engine is available in units of 10,12, 14, 16 or 18 cylinders, covering a power range from 1.800 bhp to 3.240 bhp. It is offered in the following three versions: 26MTBF-40V: Main marine engine for geared or diesel-electric installations 26MTBH-40V: Marine auxiliary engine for generator operation 26MTBS-40V: Stationary engine for driving generators or pumps In marine propulsion plants the following three drives are possible: a) One or more engines coupled through reduction and reversing gears to fixed pitch propellers b) One or more engines coupled through reduction gear only and employing controllable pitch propellers c) Diesel-electric drive with engines coupled direct to generators supplying power to an electric motor on the propeller shaft. The crankcase consists of two parts: a frame and a bedplate bolted togheter. The crankcase is provided with ventilation ducts which can be led into the air. On both sides of the crankcase, large ports give easy access to connecting-rods and main journal bearings. These ports have light metal covers. The frame which is made of cast iron, forms the main structural member of the engine. It carries the main bearings for the crankshaft, the bearings for the two camshafts, and housing with guides for the actuating gear of valves and fuel pumps. Each cylinder is attached to the frame with four long studs of special steel. The bed plate is of cast iron, and serves as reservoir for the lubricating oil. It can be provided with an amply dimensioned oil outlet with strainer to tank, if desired. The main journal bearing shells are replaceable precision components. They are of steel lined with leaded bronze and a thin galvanic layer of leaded tin. The main bearing shells are carried in the frame and have bearing caps of steel designed to allow replacement of the shells without lowering the crankshaft. The cylinders are of simple design, each consisting of a separate cylinder cover, a cylinder liner, and a cooling jacket fixed to the top of the frame with four long studs of special steel.

PE-IDM.601(B)

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EE “Antonio de Escaño” Departamento de Idiomas

INGLÉS TÉCNICO-MARÍTIMO

The cylinder liners are cast in fine-grained high quality perlite-iron. The top flange of each liner rests on the cooling jacket, while the lower ends are retained by the frame. Rubber rings are used to seal the joints between the cooling jacket and the liner, and also between the crankcase and the liner. The cooling jackets are of cast iron. They encase the cylinders and each is provided with nipples and rubber rings for inlet and outlet of cooling water.The cylinder covers are made of fine-grained cast iron. They are each fitted with two air-inlet and two exhaust valves, a centrally located fuel valve, a starting and safety valve, and a valve for measuring gas pressure in the cylinder cover to prevent contamination of circulating oil. The cylinder covers are arranged for quick and easy dismantling and refitting with the aid of hydraulic tools. The crankshaft is a single forging of high quality steel, and the crank pins and journals are induction-hardened. Each crank pin carries two connecting rods mounted side by side, one from each of pair of cylinders forming the V. The crankshaft is provided with a coupling flange for connecting to a generator shaft or for flexible coupling between engine and gear. The connecting rods are open-hearth steel forgings. The small ends are closed and provided with bronze liners. The big ends are split at an acute angle to the centre line of the connecting rod to allow withdrawal of piston and connecting rod through the cylinder liner. The connecting-rod bearing shells are replaceable precision units of steel and have leaded bronze linings provided with a thin galvanic layer or leaded tin. The mating surfaces between the rods and the bearing caps are serrated, and the bearing cap is secured with nickel steel screws.

Technical Vocabulary Dismantling Fain-grained Flange Floating Frame Fuel pump Gadgoom pin Harden, to Journal Gear box Ignition point Injector Ports

Desmontaje Textura fina, grano fino Brida Parte libre Bastidor Bomba de inyección Perno del émbolo Endurecer Muñón, luchadero Caja de engranajes Punto de inflamación Inyector Lumbreras 25

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INGLÉS TÉCNICO-MARÍTIMO Oil scrapper ring Scavenging blower Scavenging pump Scavenge valve Starting motor Radial engine Trunk piston Turbo- blower Valve rocker

Aro rascador Ventilador de barrido Bomba de barrido Válvula de barrido Motor de arranque Motor en estrella Pistón de tronco, émbolo buzo Turbo soplante Válvula de balancín

“DETROIT” DIESEL MARINE ENGINE. SERIES 149. TWO-STROKE. V-ENGINE.

SCAVENGING PUMPS VALVE

VALVES

FUEL INJECTOR

EXHAUST PISTON CONNECTING

CRANKSHAF

OIL FILTER OIL CASE / HOUSING

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CHAPTER 4 LINE OF SHAFTING – CRANKSHAFT-PROPELLER Vocabulary Bedplate Crankshaft Crankwebs Crankpins Crank-axles Collar Line of shafting Liner Gunmetal Journals Main bearings Propeller boss Tail-end-shaft Screw ship Stern tube Thrust bearing Thrust block collar Thrust block Thrust shaft

Bancada Cigüeñal Brazos del cigüeñal, guitarras Muñones de biela Muñones principales Collarín Línea de ejes Camisa Bronce de cañón Luchaderos, muñones principales Cojinetes principales Núcleo de la hélice Eje de cola Buque de propulsión mecánica Bocina Chumacera de empuje Collarín de empuje Chumacera de empuje Eje de empuje

LINE OF SHAFTING A line of shafting in a crew ship consists of: The crankshaft, thrust shaft at one end, and the other the tail-shaft and between them the intermediate shafts CRANKSHAFT The crankshaft is a portion of the shafting composed of cranks rigidly attached to one another. It converts up-and-down motion of piston into rotary motion of shaft. Crankshafts may be either forged or built-up. The built-up crankshaft is composed of a series of crankpins, crank axles, and crank-webs. The crank axles or journals are supported by the main bearings in the engine bedplate, and the connecting rods work on the crankpins.

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INGLÉS TÉCNICO-MARÍTIMO THE THRUST SHAFT

The thrust shaft rests in the thrust bearings. It is fitted immediately abaft the crankshaft and consists of a shaft with a number of collars which transmits the thrust of the propeller to the thrust block shoes and so to the ship. The thrust shaft is supported in bearings. The propeller thrust tends to push the shafting forward but each collar on the thrust shaft rubs against the face of the thrust shoe and so transmits the thrust to the block and so to the ship. INTERMEDIATE SHAFTS The intermediate shafts are fitted between the thrust shaft and the tail-end-shaft. They have a coupling at each end for bolting to the other shafts by means of the coupling bolts. TAIL-END-SHAFT The tail-end-shaft is the shaft to wich the propeller is fixed. The part of it which is inside the stern tube is fitted with a liner of gunmetal which can be renewed when worn. In the after end of the tail-end-shaft enters the propeller boss whiich is secured to the shaft by a key and a large nut which is screwed tightly on the shaft.

The Crankshaft The rigid crankshaft is a highcarbon steel drop forging carefully heat-treated to insure utmost strenght and durability. All main and connecting rod bearing journal surfaces are electrically hardened by the Tocoo process. Complete static and dynamic balance of the rotating parts has been achieved by counterweights forged integral with the crankshaft. The crankshaft thrust is taken through two-piece bronze washers on each side of the rear main bearing. The crankshaft is drilled for full pressure lubrication to the main and connecting rod bearings. Two dowels are provided in the crankshaft flange at the rear for locating the flywheel on the shaft six tapped holes, one unequally spaced, are provided for attaching the flywheel, owing to this feature, a flywheel can be attached in only one position. The six-cylinder crankshaft has 7 main bearings, each 31/2” in diameter and 1 1/8” long. Since bearing loads take place on the lower half of the main bearing shells and the upper half of the connecting rod-bearing shells, wear on the shells take place at these points PE-IDM.601(B)

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first. If, therefore, main bearing or connecting rod bearing trouble is suspected, the oil pan and the main bearing caps as well as the connecting rod bearing caps should be removed, one at time, and the lower half of the main bearing shell and the upper half of the connecting rod bearing shells inspected for scoring, corrosion, chipping, craking, or signs of overheating. If crankshaft has been overheated, erxamine the journals for cracks. The backs of the bearing shells should also be inspected for any bright spots. Bright spots on backs of the shells will indicate that shells have been shifting in their supports and are unfit for further use. If the crankshaft journals do not show signs of scoring overheating, or abnormal wear, it will be unnecessary to remove the crankshaft as the condition may be corrected by changing the worm half of the bearing shells only, providing the opposite half is in unable condition. Loose main bearings will be evidenced by the wobbling of the flywheel or a drop in oil pressure. If the crankshaft journals show signs of overheating or are scored badly, then the crankshaft must be removed and a new one substituted. When a crankshaft has been removed for reconditioning for any reason whatsoever, a through inspection should be carried out before the shaft is again installed in the engine. Such a check should include: Blow out all oil passages with air. Measure all main bearings and connecting rod bearing journals. The journals should be measured at several places on the diameter in order to show the smallest diameter in case the journals have worn out of round. Measure the thickness of the main bearing and connecting rod bearing shells.

Technical Vocabulary Bearing cap Bearing journal Bearing shell Connecting rod bearings Bright spot Cracking Crankshaft Check Drilled Dowell Drop forging

Tapa del cojinete Cojinete del luchadero Envoltura del cojinete Chumaceras de biela Punto brillante Grietas Cigüeñal Comprobar Barrenado Espiga, cabilla, guía Forja a martinete 29

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INGLÉS TÉCNICO-MARÍTIMO Flange Flywheel High-carbon steel Journal Lower connecting rod bearing Main bearings Oil pan Overheated Scoring Thrust Tapped hole Washer Webling

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Brida Volante Acero de alto carbono Luchadero Chumacera de biela inferior Chumaceras principales Batea, colector de aceite Recalentado Rayaduras Empuje Agujero para roscar Arandelas Oscilaciones

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INGLÉS TÉCNICO-MARÍTIMO THE PROPELLER Vocabulary Ahead Blade Blade flange Boss Built propeller Cavitation Controllable pitch propeller Four bladed propeller Hub Key Left-handed propeller Pitch Pitch angle Pitch ratio Propeller Propeller slip Right-handed propeller Six-bladed propeller Slip Solid propeller Three-bladed propeller Tip Twin propellers PROPELLER

Avante Pala Paso de la pala Núcleo Hélice de palas independientes Cavitación Hélice de paso variable Hélice de cuatro palas Cubo Chaveta Hélice de giro a la izquierda Paso Angulo de paso Relación de paso Hélice Resbalamiento de la hélice Hélice de paso a la derecha Hélice de seis palas Resbalamiento Hélice sólida Hélice de tres palas Punta de la pala Hélices gemelas

The propeller is a device which drives the ship through the water. It consists of a boss or hub carrying three or four radial blades of an approximately helical surface. Propellers are made of cast iron, steel, a non-corrosive alloy of manganese bronze. A propeller is right-handed when with engines turning ahead, its upper half revolves from port to starboard, and left handed when the motion is from starboard to port. The propeller boss forms the central portion of the propeller which carries the blades and forms the medium of attachment with the tail-end shaft, wich enters into the propeller boss and is fitted with a rectangular key, and over this key slides a slot of the propeller boss. The propeller is further secured by a nut which is screwed tightly on the screwed portion of the shaft.

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Controllable pitch propeller In this type of propeller the blades may be turned on their respective vertical axis, as to neutral position, astern position or ahead position. It is fitted in modern small vessels, usually in tugs whose engines of internal combustion type turn the propeller shaft continuously in one direction. Pitch Pitch is a term applied to the distance a propeller will advance during a revolution, supossing there is no slip. Slip Slip is the difference between the actual speed of the ship and the speed of the propeller or engine speed. Propellers The most common form of the propeller today is the solid propeller; wich is a single casting, the blades being cast integral with the bosses, also a very common type is “the built propeller”. The built propeller has the blades and boss cast separately, the blades being secured to the boss with studs and nuts, the heads of which usually faired into the boss with cement. The chief advantage is that, if one blade becomes damaged beyond repair, it is a relatively cheap-matter to renew the blade rather than the whole propeller. As a result, we find that a large number of the twin-screw vessels plying between the British Islands and the East, having to pass through the Suez Canal, with its attendant risk of damage to the blades, are fitted with built propellers. A further advantage is that, by elongating the holding-down stud holes, allowance is usually made for some adjustment to the pitch, should this prove desirable. The drawback, however, is that the rather large boss necessary to accommodate the blade flange or palm as it is usually known, leads to certain minor losses in efficiency. Nevertheless, if the boss is well designed, these losses should not amount to more than 1 or 2 per cent as compared with the equivalent solid propeller. Controllable-pitch propellers As it name implies, it is possible to alter, at will, the pitch of this type of propeller to suit the prevailing resistance conditions. This change is effected by rotating the blade about its vertical axis, this movement usually being carried out by hydraulic or mechanical means. The most obvious application is for the double-duty vessel, such as the tug or trawler where the operating conditions when towing or running free are entirely different. Since it is usually possible to reverse the pitch completely, and so reverse the direction of thrust, it has one 33

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obvious advantage when used in conjunction with a uni-directional prime-mover. In this latter connection, it would seem to have a considerable future when the internal-combustion turbine becomes a force to be reckoned with in the marine-engineering world. In multi-engine vessels, where varying numbers of engines have to be operated efficiently, many large controllable-pitch propellers have been supplied. Many propellers of this design, for horse-power ratings varying from 500 to over 8.000, are now in operation throughout the world in ferries, ore-carriers, pilot ships, cargo ships, cross-channel ships, canal and river traders, trawlers, ice-breakers, whalers, tugs and other ships. Hydraulically operated propellers Most widely used of the hydraulically operated propellers is the “KaMeWa”, a Swedish propeller whose basic design was developed from experience of the Kaplan water turbine; and, unlike the other principal types, has the operating servomotor positioned outboard in the hub body. The servomotor control valve is also in the hub body, and is regulated by a tube down the hollow propeller shafting. This tube also convoys the operating oil from the oil distributing box inboard to the control valve. The forward end of the shaft tube connects with a key which is moved fore and aft by a sliding ring within the oil distributing box. An auxiliary servomotor mounted externally to the box is used to move the sliding sleeve through a fork mechanism. Oil pressure is applied to the system by means of electrically driven or shaft driven screw or gear pumps. Advantages claimed for this design are, first, that the ability to change pitch in the event of the shaft becoming bent is in no way impaired; second, that all the very high forces involved in the pitch-changing operation are constrained within the boss. In the unlikely event of electrical or hydraulic failure, a spring or, in the larger propellers, a series of springs, moves the blades into full ahead pitch.

Technical Vocabulary Blade Blade flange Boss Built propellers Canal and river traders Cast, to PE-IDM.601(B)

Pala Base de la pala Núcleo Hélice de palas independientes. Buques de ríos y canales Fundir 34

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Condition of fouling Controllable pitch propeller Cross channel ship Direction of thrust Doble-duty vessel Ferry Fore and aft Fork mechanism Gear pump Holding-down stud hole Hollow propeller shafting Hub-body Ice-breaker Key Left-handed propeller Non-uniform pitch Pitch Pitch angle Pitch ratio Plying Propeller Right-handed propeller Screw propeller Screw pump Sealing ring Shaft driving Solid propeller Studs Tip Torque Trawlers Twin propellers Uniform pitch Wake Whaler

Condición del casco Hélice de paso variable Buque, para el servicio del canal Dirección de empuje Buque de doble función Transbordador De proa a popa Mecanismo de horquilla Bomba de engranajes Agujero para alojar los espárragos Eje hueco de la hélice Cono del núcleo Rompehielos Pasador Hélice de giro a la izquierda Paso no uniforme o variable Paso Angulo de paso Relación de paso Navegación de línea regular Propulsor, hélice Hélice dextrógira o de giro a la derecha Propulsor, hélice Bomba de husillo Anillo deslizante Movidos por el eje Hélice compacta Espárragos Punta de la pala Torsión Pesqueros Hélices gemelas Paso constante Estela Ballenero

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CHAPTER 5 TURBINES. TYPES Vocabulary Action turbine Ahead turbine Astern turbine Axial blow turbine Axial flow pressure turbine Barrel Blades Bush Back pressure turbine Bollows Cam Camshaft Cast, to Casing Collar Cruising turbine Disc turbine Drum turbine Dummy Diaphragm Energy of discharge Expanding nozzle Exhaust gas turbine Fins Flexible coupling Full admision turbine Full injection turbine Gas turbine Gland housing Geared turbine Grooves Governer Gunmetal Heat energy

Turbina de acción Turbina de marcha avante Turbina de marcha atrás Turbina axial Turbina axial de presión Tambor Palas o álabes Corona Turbina de contrapresión Fuelles Leva Eje de levas o camones Fundir Envoltura Corona Turbina de crucero Turbina de discos Turbina de tambor Junta laberíntica compensadora Diafragma Energía de flujo Tobera de expansión Turbina de escape de gas Aletas Acoplamiento móvil Turbina de admisión total Turbina de inyección total Turbinade gas Envolvente de prensaestopas Turbina engranada Canales, rayaduras Regulador Bronce de cañón Energía térmica o calorífica 39

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INGLÉS TÉCNICO-MARÍTIMO High pressure turbine Hoop Impulsive turbine Jet Low pressure turbine Moving blade of a turbine Nozzle Oil nozzle Parsons turbine Reaction blades Reaction turbine Radial flow turbine Rateau type turbine Reduction gear Ring of fix blades Rotor Rubbing Shaft Stages Stationary blade Steam turbine Stator Steamnozzle Sluice valve Tangential flow turbine Tandem turbine Turbine rotor Turbine wheel Turbine nozzle Turbine casing Turbine governor Turbine diaphragm Turbine disc Turbine disc key Turbine dummy Turbine seating Turbine shaft Turbine shaft bearing Throttle valve Torque Thrust bearing casing PE-IDM.601(B)

Turbina de alta presión Corona Turbina de acción Chorro Turbina de baja presión Paleta móvil de la turbina Tobera Tobera de aceite Turbina de Parsons Paletas de reacción Turbina de reacción Turbina radial Turbina “Rateau” Engranaje reductor Corona de paletas directrices Rotor Rozamiento Eje Fases Paleta fija Turbina de vapor Estator Tobera de vapor Diafragma Turbina tangencial Turbina tanden Rotor de turbina Rotor de turbina Tobera de turbina Envoltura de la turbina Regulador de la turbina Diafragma de turbina Disco de turbina Chaveta de disco de turbina Émbolo compensador de turbina Polines de turbina Eje de turbina Chumacera de eje de turbina Válvula de cuello, de estrangulación Fuerza de torsión Envolvente del cojinete de empuje 40

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INGLÉS TÉCNICO-MARÍTIMO

TURBINE The turbine is an engine in which a fluid at high pressure pushes against blades attached radially to a rotor causing it to rotate around its axis. Turbines may be classified by the fluid driving them as: air turbines, steam turbines, gas turbines. STEAM TURBINE A steam turbine is a turbine in a which steam at high pressure flows against a series of blades set on discs to the main shaft. In a steam turbine the potential energy of steam is changed into useful work in two distinct stops. First is converted into energy of motion, called kinetic energy, by the expansion in a nozzle from which the steam emerges as a jet at high speed; and second this kinetic energy is converted into mechanical energy by directing the steam jet against blades mounting on revolving rotor or by the reaction of the jet in the expanding passage, if it revolves. The turbine consists of a rotor, carrying the blades, the casing in which the rotor revolves and nozzles or stationary blades through which the steam is expanded or directed. The advantages of the steam turbines when compared with reciprocating engines, is that the turbine the turbines require less engine-room, they are lighter in weight, and require less attendance. The disadvantages are, that the condensing plant is larger and more expensive, it is required special heat resistance material, and a reduction gear to allow turbine to run at the high speed necessary for high efficiency, and the propeller at the comparatively slow for its best efficiency.

TYPES OF STEAM TURBINES There are two main types of steam turbines: impulsive turbine and the reaction turbine. Impulsive turbine. A impulsive turbine consists of a ring of nozzles followed by a row of blades mounted on a wheel. The steam is expanded in the nozzles and leaves it in the form of high velocity jets which will be imparted to the rotor blades, and the rotor will rotate at high speed and so drive the shaft. The speed of rotation of a single wheel turbine is very high and is used for small powers, for driving dynamos, etc., but the impulse turbine used on ships have several wheels fitted with blades and contained in a steam tight casing. The steam passes through a set of nozzles in a division or diaphragm and the jets of steam are directed on to the blades of the 41

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first wheel and cause it to rotate. The spent steam enters the second set of nozzles which are set in a steam tight diaphragm between the first and second wheels. Again the steam pressure falls and in its place, velocity is developed in the form of a second jet of jets which strike the second wheel blades. The steam from this wheel enters a third series of nozzles, drives a third wheel and so on. By extracting the velocity in steps or stages the turbine is made to rotate at a more reasonable speed. All the wheels are made fast at the same shaft, and all run together. The impulsive turbine is divided in H.P. turbine and L.P. turbine. When the steam has passed through several wheels in the H.P. turbine is then exhausted to the low pressure turbine and finally this low pressure turbine exhausts the steam into the condenser. Reaction turbine. A simple reaction turbine consists of a ring of fixed blades acting as nozzles and followed by a row of similar blades mounted on the rotor. One half of the stage pressure drop takes place in the fixed blades, and the steam jets enter the rotor blades in the same manner as an impulse stage. The rotor blades act as moving nozzles and expand the steam ever the remaining half of the stage pressure drop. In this type the steam expands through the fixed and moving blades, resulting in a considerable end thrust. This type of turbine is called Parson´s turbine. The blades in the first stage or expansion are relatively short and increase in lenght as the steam increases in volume. The fixed blades are attached to the inner surface of the turbine casing. GAS TURBINE The gas turbines use air which is drawn into a centrifugal or axial compresor and forced out at a pressure of several atmospheres. The air then enters a combustion chamber where fuel is injected into the air stream and ignited. The resulting high-temperature gases drive the turbine. REDUCTION GEARING The gearing is the means by which both turbine and propeller may run at their respective economical speed, the turbine at high speed and the propeller at the comparatively slow speed for its best efficiency. Turbines, impulsive and reaction are geared to the propeller by single or double reduction gear of the double-helical type.

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INGLÉS TÉCNICO-MARÍTIMO Turbines

The following information has been supplied by the Superintendent engineer of the “Blue Funnel Line”. S.S. “Nestor turbines” The turbine installation in the Blue Funnel Line S.S. “Nestor” is of the three-casing impulsive, double reduction gear. Steam is admitted to the high pressure cylinder through three groups of inserted nozzles containing (in order of opening) seven, three and two nozzles. The steam admision valves controlling these nozzles groups are housed in the top half casing, and are actuated from the manoeuvring hand-wheel by means of shafting bevel gears and Hardy-Spicer flexible couplings. The total maximum output of the turbines, using twelve nozzles is 8.000 horse power. With the H.P. turbine running at 6.000 r.p.m. a propeller shaft speed of 125 r.p.m., the maximum double-reduction gear ratio is 48%. The glands are of the labyrinth type, having nickle-lead bronze sleeves with machined internal fins registering with projections turned on the shaft. These sleeves are supported by springs within the gland housings, and the material is such that should rubbing occur in serivce, clearance will rapidly be worn without undue local heating. Gland steam is controlled by means of two hand-wheels on the right hand side of the main control panel. At full power the transfer piping between the H.P. and L.P. cylinders contains steam at 125 p.s.i.g., which results in a force of some 3 tons in the axial direction. In order to reduce this force which would apply to the H.P. and L.P. casings, the transfer pipe has been prestressed by an ingenious spring mechanism. This reduces the force acting upon it when hot and under pressure to about half a ton. When the stern throttle is opened, low pressure, low temperature steam is automatically admited to two points in the L.P. turbine. Heat produced by windage is dissipated to this steam as it flows to the condenser. The H.P. turbine-blade heights are small, and the problem does not therefore arise. No steam whatever is bled from the turbines for feed water heating. Instead a 350 kw allen back-pressure turbo generator is used continuosly at sea and to a direct-contact feed heater. In order to prevent distortion of the rotors due to temperature variations during manoeuvring periods, a quick-engaging turning gear is provided. As soon as a stop order is received, a lever mounted centrally on the turbine control desk is moved, and the main

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turbines be still trailing, a mechanical interlock comes into operation which prevents the engagement of a clutch. Once the turbine has come to rest, the interlock permits an electro-pneumatic valve to pass compressed air to a Westinghouse servomotor. This engages a fine-toothed dog-clutch mounted at the after end of the first reduction pinion of the L.P. turbine. Then contactor relays close to start the turning gear motor, which rotates the turbine, gearing and shaft assembly at a very low speed ( six revolutions per hour ). Conversely should an engine is moved to the appropiate position, when the Westinghouse electro-pneumatic cylinder will operate instantaneously to throw out the clutch. The length between bearing centres is 57 in. The mean diameter of 1st. and 2nd. rows of blades is 22 in. The mean diameter of 3rd. to 9th. rows of blades is 18 in. The height of the 1st. row of blades is o.6875 in. The height of the 9th. row is 1.292 in. The height of the last row of blades in the L.P. is 10 in.

Technical Vocabulary Astern throttle Blade Bled Block Clearance Clutch Contactor relays Double reduction gear Engagement Dog clutch Feed water heating Flexible coupling Gland housing Gland steam Hand wheel Housed Glands Fin Fulcrum Fine toothed Labyrinth type

Válvula de estrangulación de marcha atrás Paleta Pret. del verbo “to bleed” = sangrar Corredera de sector Intersticio, espacio libre Embrague Relevador, relé automático, contactor Engranaje de reducción doble Acoplo Embrague de garras Recalentador de agua de alimentación Acoplamiento flexible Envoltura de los obturadores Vapor de los obturadores Volante Alojadas Obturadores Aleta, anillo Punto de apoyo Dientes finos Tipo laberíntico 45

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INGLÉS TÉCNICO-MARÍTIMO Lever Manoeuvring Main control panel Interlock Nozzle Prevent, to Quick engaging Ratio Output P.s.i.g. Pre-stressed Sequence Seal stop Shafting bevel gear Sleeve Spring leaded Rubbing Three casing impulse Throw out Top half casing Transfer piping Trail, to Turning gear Windage Worn

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Palanca Maniobra Panel de mando principal Bloqueo Tobera Evitar Acople o embrague rápido Proporción Potencia Pounds square inch gage Reforzado Sucesión, serie Cierre Engranaje cónico Manguito De resorte Fricción, rozamiento Turbina de acción de tres envolventes Desengranar Mitad superior de la envolvente Tubería de paso Arrastrar Virador Pérdida de energía por efecto del viento Gastado

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CHAPTER 6 AUXILIARY MACHINES Vocabulary Anchor cable Anchor work Barrel Bed plate Bearing keep Boom Brakes Cable lifter Connecting rod Crank disk Crosshead Cylinders Cylinder drain cocks Chain locker Chain pipe Drumhead Exhaust pipe Forecastle head Gear, to Foot brake Hatchway Hawse pipe Heaving in Hoist, to Main wheel Mooring lines Pinion Piston rod Reversing lever Screw brake nut Shaft Single purchase Small spur wheel Spur wheel Steam chest

Cadena del ancla Faenas con el ancla Tambor o cilindro Bancada Cojinete del eje principal Pluma de carga, botalón, botavara Frenos Barbotín Barra de conexión Plato Cruceta Cilindros Grifos de purga de cilindros Caja de cadenas Bocina Sombrero (del cabrestante) Tubo de vapor de exhaustación Castillo Engranar Pedal del freno de cinta Boca de escotilla Escobén Virar Izar Engranaje principal Cabos de amarre Piñón Vástago Sable o palanca de cambio Mecanismo de engranaje del barbotín Eje Guarnido en sencillo Engranaje de eje secundario Engranaje recto Caja de distribución 47

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INGLÉS TÉCNICO-MARÍTIMO Steam pipe Steam pipe flange Stop valve Spindle Tie rod Warping ends Wildcat Winch Windlass

Tubo de vapor de admisión Brida de la tubería de vapor Válvula de vapor Eje Estay de chigre Cabirones Barbotín Chigre, maquinilla Molinete

WINCH A winch is a hoisting or pulling machine which turns a shaft on which is fitted a drum and two warping ends, and used principally for the purpose of handling, hoisting and lowering cargo from a wharf or lighter to the hold of a ship. It is also used to take up lines in the manoeuvres of docking or undocking. Merchant ships usually have at least two winches at each hatchway. The driving power is usually steam or electricity, in the case of steam, this is supplied from the boiler and the supply is controlled by a steam stop valve, and the exhaust steam from each cylinder returns to the condenser. The steam is admitted to the cylinder and then by means of the piston, piston rod and connecting rod causes the crank to rotate and so converts the reciprocating motion of the piston into rotary motion of the engine shaft. The cylinders are fitted with a drain cock, so that any water formed by condensation of the steam in the cold cylinder when starting can be removed and thus prevent damage to the cylinder. The winch can be geared in single purchase to lift light loads quickly or put into double purchase to lift heavier load more slowly.

WINDLASS The windlass is a type of winch designed for heaving in an anchor cable. When not employed in anchor work the windlass can be used for heaving in mooring lines. It is installed on the forecastle head so that chains on both bower anchors lead straight, over their respective wildcats from hawsepipes to chain lockers.

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The driving power is usually steam or electricity; the steam windlass has two cylinders which by means of a piston, piston rod, connecting rod and crank, drive the engine shaft; and the engine shaft by means of a pinion moves the intermediate shaft. On this shaft are fitted the warping ends. The intermediate shaft has two pinion which move the main wheels on the main shaft and these wheels, may be connected at will, by means of a clutch to its respective cable lifter or wildcat, and so it is possible to heave in both anchors when both clutches are engaged, or to heave in one only, when it is engaged the port or starboard clutch.

CAPSTAN The capstan is a machine designed for heaving in mooring lines. It consists of a vertical barrel working on a spindle. The driving power is usually steam or electricity. In the traditional capstan the top of the barrel has square sockets in which capstan bars may be placed when working by hand. The lower edge of the barrel carries pawls which engaged in a rack and prevent capstan reversing or walking back. The modern capstan has both worn gearing and bevel spur gearing. The worn wheel shaft drives a bevel pinion which in turn engages with a bevel wheel secured to the underside of the capstan.

Electric Winches A large percentage of electric winches are worm driven, whiel others are driven through epicyclic gearing. With a worm-geared electric winch the magnetic brake is generally at the commutator end, and the centrifugal and foot brakes at the end of the shaft beyond the worm casing. The bearings for the worm wheel shafts are arranged to give the maximum stiffness to the shafts, with any tendency towards bending reduced to a minimum. This is of importance, as a winch is subject to sudden shocks. The worm-shaft thrust bearing is now usually of the duplex-type ball bearing. The earlier designs were fitted with the ordinary thrust disc-type ball bearing, and due to centrifugal force at the high light-load speed it was found that the bearing balls had a tendency to exert pressure on their housing, thus wearing them away quickly. A popular worm-driven winch is the Scott winch. This has a mechanical efficiency of about 85 per cent and, an electrical efficiency of about 90 per cent. It embodies a serieswound motor with a speed-limiting shunt winding, magnetic, foot and centrifugal brakes and contactor control gear, an overload device is also incorporated. The motor is controlled in 49

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both directions of rotation by series resistances. The speed is limited to a safe valve by the shunt winding when the winch is running light and by the centrifugal brake when it is lowering the load. The lowering speed can be controlled by the magnetic brake, which is fitted with hand control. Epicyclic gearing .- With a winch having epicyclic gearing the motor armature is concentric with the barrel shaft. This type of winch is usually controlled so that the magnetic and centrifugal brakes are not required, and the winch is fitted with a foot brake only. The Wilson winch is of a special type, with a motor designed to run at a slow speed of about 100 r..p.m.. This motor is mounted so as to run free on the barrel shaft and drives this shaft through epicyclic gearing. It has an electrical efficiency of 75-80 per cent and a mechanical efficiency of about 97 per cent. The motor is series wound with a speed–limiting shunt winding, the controller being of the the contactor type with hand-operated master controller. A foot brake is also fitted. Windlass The main purpose of a ship´s windlass is to lift the anchor, and for warping. The windlass is fitted with a cable-lifter or drum, one for each cable. These lifters are fitted to run freely on a shaft. They are constructed to fit the links of the cable, and the lifter is made to fit four or five links round its cicunference, known as four and five snug. Actually there are only two links engaged at any one time. On the outer edge of the lifter there is a rim to take a brake band, and on the end are arranged, side jaws which are made to fit into corresponding jaws on a gear wheel. This gear wheel is pressed on to the shaft. In order to clutch or declutch the lifter to or from the gear. A groove is turned in the boss of the lifter, into which two cods are fitted. These cods are attached to a carrier, which is moved bacwards and forwards by means of screws geared to a handwheel. A second motion shaft is fitted with clutch pinions which mess into the gear-wheels on the lifter shaft. This shaft is also fitted with a warping drum at each end, and when these are in use the cable lifter shaft is disconnected by declutching the pinions. Geared into this shaft is the first motion shaft, on which the engine or motor is attached, the first from crank discs and the second to further gearing. Electric Windlass.- An electric windlass equipment should incorporate the following features: a) The armature of the motor should be designed to keep the momentum as low as possible. b) A sliping clutch or its equivalent should be fitted to limit the stress which can be imposed by the applied power, by braking or by the inertia of the moving parts; to a predeterminated limit based on the proof stress of the cable. PE-IDM.601(B)

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c) The maximum possible speed within the limits of the available bhp should be obtained by increasing the speed at the lighter loads by means of field control. d) The equipment should give a creeping speed which will house the anchor safely and allow the motor to stall when the throat of the hawsepipe is reached. e) The motor must not be disconnected from the circuit on overload. Any excesstorque device fitted must only reduce the torque to a safe limit. Capstan The capstan is generally used for warping (changing a vessel´s position with regard to a wharf, dock or another vessel tied to a wharf, by means of a common line) and sometimes for pulling objects in a horizontal direction or handling ground tackle. It is a verticalbarrelled, rotating device, with pawls at its base to prevent it from reversing, arranged for either hand or hand and power operation. Power-driven capstands, steam or electric, consist primarily of the capstan itself, the reduction unit and the prime mover. The entire machine can be mounted above deck, or the gear unit and motor or engine can be situated below deck, connected to the extended capstan shaft. Power-driven units are usually arranged to operate in either direction,and in some cases where reversing features are incorporated, the pawls at the capstan base are eliminated. When found on reversing types, the pawls are equipped with thumb screws to hold them in a raised position so that the barrel may be rotated in a reverse direction.

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INGLÉS TÉCNICO-MARÍTIMO Technical Vocabulary Armature Bacwards Barrel shaft Bearing balls Bending Boss Brake Brake band Cable lifter Capstan shaft Clutch, to Cods Commutator Contactor control gear Crank disc Creeping speed Declutch Epicyclic gearing Field control Forwards Foot brake Gear wheel Groove Ground tackle Light load Links Master controller Mesh, to Overload Pawls Prime mover Proof Reduction unit Rim Run light, to Series-wound motor Shunt winding Slipping clutch Stall, to Thumb screws Warping Warping drum Wear away, to Wharf Worm driven PE-IDM.601(B)

Inducido Hacia atrás Eje del tambor Cojinete de bolas Flexión Núcleo Freno Banda del freno Barbotín Eje del cabrestante Engranar Pequeños sectores Colector Engranajes contactores Plato Marcha muy lenta Desengranar Engranaje epicíclico Control de campo Hacia delante Freno de pié Rueda dentada Garganta Equipo de fondear Carga en vacío, ligera Eslabones Control principal Engranar Sobrecarga Trinquetes Elemento motor Prueba Elemento reductor Reborde Girar en vacío Motor de bobinado en serie Embobinado en derivación Embrague amortiguador Parar Palomillas Virar cabos Cabiron Desgastar Muelle Transmisión por tornillo sin fin 52

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CHAPTER 7 PUMPS Vocabulary Air pump Ballast pump Bilge pump Bucket Bucket pump Centrifugal pump Circulating pump Chest Delivery valve Double acting pump Duplex pump Exhaust port Feed pump Fuel pump Lever gear Outlet Plunger pump Ports Prime, to Pump barrel Pump box Pump primer Pump rod Pump well Radial vanes Reciprocal pump Rocking lever Rotary pump Scavenge pump Screw pump Self-priming pump Single-acting pump Steam slide valve chest Suction pump Suction valve Single suction pump Vacuum Valve gear pump

Bomba de aire Bomba de lastrado Bomba de sentina Émbolo de bomba Bomba con válvula de émbolo Bomba centrífuga Bomba de circulación Caja de bomba Válvula impelente Bomba de doble efecto Bomba doble Orificio de escape Bomba de alimentación Bomba de combustible Balancín Salida Bomba de émbolo buzo Orificios Cebar Cuerpo de la bomba Caja de bomba Cebador Vástago de la bomba Pozo de la bomba Paletas radiales Bomba alternativa Balancín Bomba rotatoria Bomba de barrido Bomba de hélice Bomba autocebable Bomba de efecto simple Caja de distribución Bomba aspirante Válvula aspirante Bomba de aspiración simple Vacío Balancín de la bomba

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These auxiliaries may be driven by steam, electric motors or internal combustion engines. They include: Air pump for extracting the condensed water and vapour from the condenser, and so maintain the vacuum produced by the condensation of the steam. There are two types of air pumps: The common air-pump which has three sets of valves, the lower set are foot valves, next the bucket valves and on top are the head valves. The Edward´s air-pump, in this pump there is only one set of valves, head valves. The condensed steam is allowed to flow continuously by gravity from the condenser into the bottom of the pump. On the down stroke of the bucket the water is projected at a high velocity through the ports into the working barrel; the rising water is followed by the rising bucket which closes the ports and discharges the water and air through the valves at the top of the barrel. The lower part of the pump is made conical to suit the bucket. Circulating pumps are used to circulate sea-water through the tubes of the condenser. There are two types of circulating pumps: the ordinary simple or double acting reciprocating pump, and the centrifugal pump. In the centrifugal pump the mechanical power delivered to the shaft of a centrifugal Pump by the driving engine is transmitted to the water by means of a series of radial vanes, the water is admitted into the centre of pump and is gradually put into motion and whirled round until it arrives at the outlet and to the condenser. Feed pumps for supplying fresh water to the boilers to maintain water level. Feed pumps are either worked by the main engine or are independent, such as Weir´s, Worthington´s, etc. Lubrication pumps for supplying oil under pressure to the various working parts of the engine as: bearings, gearing, etc. Fuel pumps for supplying furnace fuel oil under pressure to the sprayers on the boilers. Scavenging pumps for introducing scavenging air into cylinders of internal combustion engines, during exhaust period, displacing burn products and supplying fresh air. Feed pumps : Worthington high-pressure centrifugal pump The Worthington high-pressure bvarrel type centrifugal pump is a double casing pump. The vertical-split inner casing encloses the working parts and is surrounded by an outer casing barrel. The cylindrical casing barrel and all pieces welded to it are made of forged steel. The suction and discharge nozzles are integral with the casing to permit removal of all internal parts without disturbing the piping connections. PE-IDM.601(B)

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The chrome steel impellers are of the single-suction enclosed type of special design. Each impeller and la_ter the entire rotor is dinamically balanced. The shaft is made of heat-treated alloy steel. To facilitate installation and removal of the impellers, it is machined with steps of decreasing diameter through successive stages. The shaft sleeves are scured against axial movement by shaft sleeve nuts. The internal assembly consists of the shaft with impellers, twin volutes with bushings and stage pieces with wearing rings; it is held together by staybolts. There are four different shaft sealing arrangements applicable to these pumps: packed stuffing box, floating ring seal, fixed breakdown seal, and mechanical seal. The inboard and outboard bearings are steel-back babbitted and horizontally split. Each bearing support is fitted with adjusting screws and locknuts which permit final location of the bearings using a dial indicator to check the shaft position. The base is of welded steel construction with the pump supported at its horizontal centerline. The pump is doweled to the base at the suction end, so that all expansion due to temperature rise occurs from this point. Complete overhauls A centrifugal pump should not be opened for inspection unless there is definitive evidence that is capacity has fallen off excessively or unless noise or driver overload indicates trouble inside the pump. Under normal operating conditions, the length of service before renewal of internal parts is required should be 50.000 to 100.000 hours. The troubles which may occur with pumps and their causes are: Troubles Failure to delivery water Insufficient capacity Insufficient discharge pressure Pump requires excesive power Pump becomes steambound Pump overheats and seizes Stuffing box leaks excessively Packing has short life Pump vibrates or is noisy Bearings have short life Floating seal leaks excessively Fixed breakdown seal leaks excessively The main causes for these troubles are: Pump not primed 55

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Insufficient margin between suction pressure and vapor pressure Insufficient speed Impeller passages partially clogged Wrong direction of rotation Fluctuations in heater pressure at the suction Wearing rings, impeller or balancing device worn or damage Speed to low, or too high Foreign matter in impeller Bent shaft Rotating parts rubbing on stationary parts Packing improperly installed Suction valve closed Misalignment Bearings worn Rotor out of balance, resulting in vibration Excessive thrust caused by a mechanical failure inside the pump or by the failure of the hydraulic balancing device Shaft sleeves worn or scored at packing Incorrect type of packing for pressure and temperature conditions Gland too tight, resulting in lack of leakage to lubricate packing Failure to provide cooling water to stuffing boxes The frequency of a complete overhaul depends upon the hours of work, operation, of the pump, the conditions of service and the care pump receives in operation.

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INGLÉS TÉCNICO-MARÍTIMO Technical Vocabulary Axial clearance Babbit metal Bearing Bent Bush, bushing Clearances Clog, to Clogged Dowel, to Foreign matter Forge steel Foundation Gland Heater pressure Impellers Inboard Keys Lack Leakage Locknuts Machined Misalignment Nozzles Outboard Overhauls Packing Power Prime, to Ring seal Sleeve Sleeve nut Staybolts Stage of a pump Steambound Stuffing box Thrust Thrust bearing Tight Troubles Twin volute Volute Wearing rings

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Huelgos axiales Metal antifricción Chumacera, cojinete Doblado, encorvado Casquillo, manguito Huelgos Atascar, obstruir Atascado Afirmar, empernar Materia extraña Acero forjado Asiento, basamento Prensa, prensaestopas Presión del calentador Impulsores Interior Chavetas Ausencia, falta Escape, filtraciones Contratuercas Ajustado Desalineamiento Toberas Exterior Revisiones, reparaciones Empaquetadura Potencia, fuerza Cebar Anillo obturador Manguito, casquillo Casquillo de tuerca Espárragos, estays Grado de aspiración Salto de vapor Caja de prensaestopas Empuje Cojinete de empuje Apretado, ajustado Averías Difusor Voluta (forma espiral) Anillos desgastables

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CHAPTER 8 CONDENSERS AND EVAPORATORS Vocabulary Air pump Aluminium bronze Brass Circulating pump Condenser Cupre-nickel Exhaust steam Expanded Cotton-cord packing Ferrules Feed water filter Feed water heater Overboard Riveted steel shell Single flow condenser Screwed glands Stays Stuffing box Surface condenser Tube plates Two flow condenser

Bomba de aire Bronce de aluminio Latón Bomba de circulación Condensador Cuproníquel Vapor de evacuación Mandrilados Empaquetadura de cordones de algodón Férulas Filtro de agua de alimentación Calentador para agua de alimentación Por encima de la borda Envuelta de chapa de acero remachada Condensador de circulación simple Prensas metálicas roscadas Tirantes Caja de empaquetaduras, prensaestopas Condensador de superficie Placas de tubos Condensador de circulación doble.

CONDENSER A condenser is vessel in wich is received exhaust steam from a recripocating or turbine engine for purpose of converting such steam to liquid state and so recovering in large measure. The two principal types of condensers are: Contact condenser Surface condenser The surface condenser is the type used nowadays, which consists of a riveted-steel shell through which passes a large number of brass tubes. Sea water is pumped through the tubes by means of the circulating pump and thence overboard.

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The steam condenses on the surfaces of the tubes and drops to the bottom of the condenser and then is extracted by means of the air pump and discharged through a feed water filter to the feed pump which pumps it to a feed water heater and then by means of another pump to the boiler. The circulating water may be made to pass through the tubes, one, two or three times and so the condensers are of single flow, two flow condenser, etc. The tubes at the tube plates are fitted with screwed glands or ferrules and sealed with cotton-cord packing; at the water inlet they are expanded. EVAPORATOR The evaporator is an auxiliary machine which converts sea water into fresh water, to compensate the less in boiler feed-water or for domestic services. It essentially consists of a chamber in which steam is passed through copper coils of tubing in order to vaporize admitted sea water. The steam from the sea boiler passes to the condenser where is converted into the liquid state. Operation in a surface condenser Formerly, a condenser was regarded merely as a “box of tubes” and its function as a convenient means of getting rid of the exhaust steam at low pressure, thus providing some cclean boiler-feed water. It is worth considering for a bit the actual processes going on in the condenser which will help towards a clearer understanding of the features of modern condensers. First, and primary importance, the steam condenses at its saturation temperature and for its complete condensation it is necessary only for its latent heat to be removed by the circulating water. If any sensible heat is removed, the condensate temperature falls below that corresponding to the exhaust steam pressure, and the sensible heat so removed is a loss. Secondly, not only does the condenser condense the exhaust steam, but it also maintains the vacuum in the exhaust system. The manner of the air removal is of importance, as the presence of air in the condenser is also responsible for undercooling of the condensate. Just as it is necessary to have a pressure difference to cause a fluid to flow from one vessel to another, so it is necessary to have a temperature difference between the steam and the circulating water to cause the heat to flow from the steam to the water. In passing through the condenser the circulating temperature rises, and if the steam temperature is assumed constant, the temperature difference between the steam and water is large at the water-inlet end and small at the water-outlet end. PE-IDM.601(B)

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The heat flow from steam to water is then controlled by the mean temperature difference between steam and water. Air quantity and pressure In a surface condenser it is impossible actually to condense all the steam; there is always left behind a certain quantity of vapour having the same properties and behaving in the same manner as the L.P. exhaust steam. Arrangements of tubes Condenser are no longer indiscriminately packed with tubes, but the tubes are carefully arranged witha view to one or more of the following objects: 1º.- To ensure that each particle of steam encounters only the minimum cold surface required for its complete condensation and to provide for the condensate falling to the bottom clear of any tubes to avoid undecooling of the condensate. 2º.- To by-pass a certain proportion of the steam round the tubes and allow it to condense by direct contact in the “rain” of condensate falling off the tubes, thus heating up the latter to nearly steam temperature. 3º.- To ensure that all tubes are continuously swept by steam to prevent the air blanket building up and reducing heat transmission. 4º.- To ensure that steam can penetrate right down to the bottom rows of tubes and so render effective the greatest possible amount of cooling surface. Effects of circulating-water velocity through the tubes Here again there are two conflicting features: 1. The higher the water velocity through the tubes, the faster the heat is carried away, and hence the greater the heat transmission. The condenser may therefore be made smaller for any given steam quantity the vacuum may be increased by increasing the tube velocity. 2. The water-friction loss in the tubes increases as the square of the velocity, hence the pumping power increases accordingly. Good condenser design and operation therefore aims at obtaining the highest possible tube velocity commensurate with reasonable pumping power.

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INGLÉS TÉCNICO-MARÍTIMO Technical Vocabulary By-pass Exhaust steam Feed-water Latent heat Packed Cooling Vacuum Water-inlet Water-outlet Rows

PE-IDM.601(B)

Derivación, paso Vapor de escape Agua de alimentación Calor latente Aglomerado, relleno Enfriamiento Vacío Admisión de agua Salida de agua Filas, hileras

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CHAPTER 9 VALVES Vocabulary Admission valve Air starting valve Balance valve Balanced slide valve Ball valve Bilge suction valve Blow off valve Body Butterfly valve By-pass valve Charging valve Check valve Discharge valve Exhaust valve Feed valve Gland Gate valve Feed check valve Handwheel Injection valve Main valve Main stop valve Manoeuvring valve Non-return valve Outlet valve Pressure reducing valve Reducing valve Poppet-valve Relief valve Safety valve Scavenge valve Sea valve Screw down valve Slide valve Seat Sluice valve Spherical valve Spring Spring loaded valve

Válvula de admisión Válvula de aire de arranque Válvula compensadora, equilibrada Válvula distribuidora equilibrada Válvula esférica, de bola Válvula de aspiración de sentinas Válvula de extracción Caja o cuerpo de la válvula Válvula de mariposa Válvula de derivación, auxiliar Válvula de carga Válvula de retención Válvula de descarga Válvula de escape Válvula de alimentación Prensaestopas Válvula de compuerta Válvula reguladora de alimentación Volante de la válvula Válvula de inyección Válvula principal, de comunicación Válvula de cuello Válvula de maniobra (turbinas) Válvula de retención Válvula de salida Válvula de reducción de presión Válvula reductora Válvula de disco con movimiento vertical Válvula de alivio, de descarga Válvula de seguridad Válvula de barrido Válvula de fondo, inyección Válvula de asiento ordinaria Válvula de distribución Asiento de la válvula Válvula de compuerta, corredera Válvula esférica, de bola Resorte Válvula de resorte 65

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INGLÉS TÉCNICO-MARÍTIMO Spring loaded safety valve Starting valve Steam reducing valve Steam admission valve Stem Stop valve Suction valve Throttle valve Valve chest

Válvula de seguridad de resorte Válvula de arranque Válvula reductora de vapor Válvula de admisión Vástago Válvula de globo, de cierre Válvula de aspiración Válvula de cuello Caja de distribución

VALVES A valve is a device for controling flow of a fluid in a pipe or conduit. SLIDE VALVES The function of the slide valve is to admit steam to the cylinder and cut off supply when sufficient steam has been admitted, and opening and closing to exhaust. By means of this valve the steam is admitted first to one side of the piston and then to the other side. This valve has a straight line reciprocating motion bearing a definite relation with the piston. SLUICE VALVES OR GATE VALVES These valves are so named from its gate or disc usually wedge-shaped, which moves perpendicularly to the direction of the flow, giving a straight passage of flow of the diameter of pipe. These valves are used in pipe lines. NON-RETURN VALVES OR CHECK VALVES Are valves permiting flow in one direction only; valve is opened by flow of fluid and closed by weight of the check mechanism when flow cease, or when the fluid attempts to pass in the opposite direction. SAFETY VALVES Safety valves are automatic relief valves that are set to open at a predetermined pressure, in the event of excess pressure in boiler, evaporators, air compressors, etc. The load on a safety valve to balance the pressure may be applied in three ways: 1st. By a simple lever and adjustable weight. 2nd. By a deadweight placed directly over the place. 3rd. By the compression of a spring. The safety valve should close quickly when the pressure has been reduced to the working pressure, which the valve is set to blow. PE-IDM.601(B)

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STOP VALVES The stop valves control the supply of steam from boilers to the main engine or engine room pumps or winches, windlass, etc; in the first case the valve is called main steam stop valve and in the other case auxiliary steam stop valve. SCREW DOWN VALVE A valve which is opened and closed against a seat by means of handdle which rotates the spindle and the valve which is attached to the lower and of it, by means of a screw thread. An example of this type is the glove valve. SEA VALVE The sea valve is a valve located near the outside plating of a vessel to supply sea water to the fire pumps, condensers, for flooding the ballast tanks, also for discharging water overboard from bilge pumps, ballast pumps, etc. MANOEUVRING VALVE This is a special valve in a turbine used for increasing and decreasing speed as required during manoeuvring of the ship.

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CHAPTER 10 COMBUSTIBLES & LUBRICANTS Vocabulary Acid number Acidity Additives Anti-foam Anti-oxidation additives Anti-rusting additives Ashes Asphalts Bloom Brown coal tar Calorific capacity Cetane number Characteristics Coke Crude oil Density Diesel-oil Distillation Dropping point Ductility Engler Fatty oil Fire point Flash point Fuel consumption Fuel oil Gas-oil Good grade Gravity Grease Grease, to Heavy duty oil Ignition point Inhibitor Kerosene

Indice de acidez Acidez Aditivos Antiespumante Aditivos antioxidantes Aditivos anticorrosivos Cenizas Asfaltos Fluorescencia Alquitrán de lignito Potencia calorífica Número de cetano Características Coque Aceite bruto (sin refinar) Densidad Diesel-oil Destilación Punto de gota Ductilidad Viscosímetro Aceite graso Punto de combustión Punto de inflamación Consumo de combustible Combustible Gasoil Buena calidad Peso específico Grasa Engrasar Aceite heavy duty, detergente Punto de inflamación Inhibidor Aceite lampante 69

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INGLÉS TÉCNICO-MARÍTIMO Kinematic viscosity Linseed oil Lubricate, to Lubricating oil Melt point Melting point Mineral oil Oil Oil sump Paraffin Penetration Petrolatum Pour point Precipitates Synthetic oils Shale oil Self lubricating Self-ignition point Sludge Sump Sulphur Solubility Tars Thick fat Turpentine Vaseline Vegetable oil Viscosity Viscosity index O.M. (Oil mineral) O.M.D. (Oil mineral detergent) O.C. (Oil compounded) O.E.P. (Oil extreme pressure) O.F. (Oil fatty) O.X. (Oil miscellaneous)

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Viscosidad cinemática Aceeite de linaza Engrasar Lubricante Punto de fluidez Punto de fusión Petróleo Aceite Colector de aceite Parafina Penetración Petrolato, vaselina Punto de congelación Precipitados Aceites sintéticos Aceite de esquisto Lubricación automática Punto de autoinflamación Lodo Colector de aceite Azufre Solubilidad Alquitranes Grasa consistente Trementina Vaselina Aceite vegetal Viscosidad Indice de viscosidad Aceite mineral Aceite mineral detergente Aceite compuesto Lubricante para alta presión Lubricante graso Aceite diverso

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SOLID FUELS Coal is the main solid fuel, and can be classified as: • Lignite • Subbituminous coal • Bituminous coal • Anthracite Lignite is the coal containing less than 8.300 btu (british termal units) of potential heat. Subbituminous coal is the coal with a btu content greater than 8.300 and less than 13.000. Bituminous coal is the coal with a btu content greater than 13.000 and is used in large quantities for power generation and industrial heating. Bituminous coal is also widely used for making coke. Anthracite is the coal with a fixed carbon content greater than 86%. Anthracite ignites less readily than other coals, but maintain an uniform and content fire. In addition to its classification by rank coal, is also classified by grade according to the amount of ash yielded when the coal is burned. High grade coal produces little ash, and low grade coal produces large quantities of ash.

LIQUID FUELS: CRUDE OIL Crude oil is destilled by heating it to about 650º F. as it is pumped through coils or pipe in a furnace. Only a heavy residual oil remains in liquid form as the lighter fractions vaporize. Both residual oil and vapors go from the furnace into a fractionating tower, which may be 100 ft. tall, and which contains a series of perforated trays, one above the other. The hot vapor rises through the perforations, and the residual oil flowa to the bottom of the tower. As the vapors rise, they become cooler, the various fractions condensing on the trays at progressively lower temperatures. Lubricating oil condenses first, about halfway up in the tower. Slightly higher a liquid called gas-oil condenses, and above that kerosene is formed. Gasoline condenses near the top of the tower, and the remaining vapours are drown off for further processing. As crude oil is steadily pumped through the furnace, the fractions flow continuously from the condensing trays into pipes that go to other parts of the refinery.

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By further distillation the residual oil is made to yield gas-oil, fuel-oil, asphalt and coke. The lubricant oil and kerosene are purified with chemicals and made ready for marketing. The raw gasoline, after chemical purification is blended with other petroleum products to make various grades of commercial gasoline. Gas-oil is either purified or converted into several other products. TYPES OF LUBRICANTS Lubricants are classified by origin such as: mineral, vegetable or animal, and by the state in which exist, such as gas, liquid or solid. Vegetable oil include: olive, soybean, caster and cotton seed. Typical solid lubricants are: graphite, molybdenum and tale. The mineral oil forms the base of the the majority of lubricants and they can be adapted by addition of various substances to improve its suitability for various used. Some of the various substances that can be adapted are: Vegetable oil are added to oils which are required to lubricate moving parts where water is present. Detergent additives are used in internal combustion engine oils to hold the carbon formed by combustion of the fuel and lubrication oil in suspension. Anti-oxidation additives are used in oils when they are exposed to hot gases or hot engine parts. Anti-rusting additives and anti-foaming additives are used in turbine oils. Anti-wear additives are used in hydraulic oils. Viscosiity improver additives are used in internal combustion oils where it is necessary to decrease the normal change of temperature. Soaps are combined under heat and pressure with mineral oils to form greases.

Combustibles & lubricants 50 years of Diesel Engine Lubrication by J.C. Nairm. Since the inception of the large, low speed diesel engine as a marine prime mover in 1913, and especially since 1920, when it emerged as a serious competitor to the to the steam PE-IDM.601(B)

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reciprocating engine and the steam turbine, the big diesel engine has presented lubrication specialists with difficult problems. In the early days of the marine diesel engine only straight mineral oils were available for lubrication. The relatively high temperatures of the ring zone and piston undercrowns placed severe demands upon the oxidation stability of oils used for cylinder lubrication, so that sticking piston rings and skirt deposits were often troublesome, and port blockage occurred in two-stroke engines. Where crankcase oil was employed for piston cooling, undesirable carbonaceous deposits formed on piston undercrowns due to over overheating. A major improvement in lubrication oil refining was introduced from 1929 onwards, namely solvent refining. Hitherto, lubricating oils had been manufactured by acid treatment of suitable cuts from a simple fractionating tower, also treatment of residues from suitable crude oils. By treating the raw lubricating oil fractions with selected solvents to remove undesirable constituents, the resultant finished oils have greatly improved viscosity indexes and oxidation stability, while the tendencies to form sludge and varnish are reduced. There are, however, some disadvantages of solvent refining. In adition to removing deleterious unsaturated constituents the process also removes compounds which, to a degree, act as natural anti-oxidants and lead-carrying agents. Basic properties desirable in a diesel engine lubricants. Diesel engine lubricants must always posses good load carrying properties. These are closely related to the type of oil used and especially its viscosity and viscosity index. A careful balance must be achieved between an oil with a sufficiently high viscosity at all temperatures encountered in the working parts of the engine (thus preventing metal-to-metal contact and wear), and yet not so high as to cause excessive fluid friction and subsequent power lose. Ideally, the VI should be so high that there is no change of viscosity with temperature. Unfortunately, this cannot be achieved in practice, even with the use of special additives which markedly increase the VI. Paraffinic oils have high natural viscosity indexes also good oxidation stability, but unfortunately when exposed to high temperatures in the ring zones of diesel engines they tend to form bands which will produce deposits. Oil additives Simple additives, such as fatty oils blended into mineral oils to improve load carrying have been used for many years. The use of chemical-type additives to improve the natural properties of mineral oils, or to enhance existing properties is, however, of much more recent origin. The use of these special additives, which has revolutionized lubricants, commenced in the mid-1930s. 73

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For example, as early as 1935 C.C. Wakefield and Co. Ltd. (now part of BurmahCastrol) were granted a patent for “Improvements in relation to the treatment of Lubricant Oils”. In effect this was to reduce and control oxidation by the incorporation of small amounts of metallic soaps and other compounds into good mineral oils bases. Improved oxidation inhibitors or antioxidants are now universally incorporated in diesel engine lubricants. These have grreatly extended the useful service life of dual-purpose and crankcase oils, especially of solvent refined oils. Cylinder lubricants Special lubricants have been developed after years of research which combine high alkalinity to neutralize corrosive sulphuric acid, and detergency to minimize deposits formation: anti-oxidants are also incorporated. Modern diesel cylinder oils now have an initial alkalinity, expressed as total base number (TBN) of about 65. By using lubricants with good detergency and load-carrying properties cylinder liner wear is well below normal for much less severely rated engines. As long ago as the late 1930s, long before the burning of residual fuels became common in marine diesel engines, additives were developed which possessed the property of keeping the piston ring zones and skirts free from carbonaceous deposits. Such oils, commonly termed detergent or heavy duty (H.D.) oils are new almost universally used for trunk-piston diesel engines of all types. Bearing lubrication As compared with cylinder lubrication, satisfactory lubrication of the bearings and other running gear of marine diesels is less difficult. With trunk-piston engines, using a dualpurpose lubricant, a medium viscosity oil possessing suitable detergency alkalinity properties, gives good performance in the bearings. In crosshead engines the crankcase oil is used for the lubrication of the running gear only and, in general, with good bearing design, a high quality oxidation-inhibited oil is adequate. It is a far cry from the straight mineral oils adequate for engines in the 1920s, to today´s scientifically formulated and carefully tested alkaline/detergent cylinder oils, also highly alkaline, for large trunk-piston engines. Ther is little doubt that conditions will become even more arduous in the future and that more sophisticated lubricants will be developed to mean engine.

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Blockage Carbonaceous Cooling Crankcase oil Crude oil Cut-off Cuts Fractionary tower Fractionate, to Inception Lubricating oil Lubrication Non-additive Overheating Oxidation Paraffinic Port Raw Ring Research Refining Sludge Solvent Sticking Skirt Steam reciprocating engine Steam turbine Straight Trouble Two-stroke engine Viscosity Viscosity index Varnish

Obstrucción, bloqueo Carbonoso Refrigeración Aceite de carter Petróleo crudo Grado de admisión Rebajas Torre de destilación Destilar Principio, comienzo Aceite lubricante Lubricación Sin aditivo Recalentamiento Oxidación Parafínico Lumbrera Crudo, bruto, materia prima Aro, anillo Investigación Refinación Cieno, lodo Disolvente Pegajoso Faldón del émbolo Máquina alternativa de vapor Turbina de vapor Puro Avería Motor de dos tiempos Viscosidad Indice de viscosidad Barniz

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CHAPTER 11 MEASURES. UNITS. INSTRUMENTS Vocabulary Barometer Brake Horse Power (B.H.P.) British Thermal Unit (B.T.U.) Bushel

Barómetro Potencia al freno, potencia efectiva Unidad inglesa de calor Medida de áridos (36,35lts.U.K.,35 lts, EE.UU.) Cable (1/10 de milla) Indicador de presiones Dinamómetro Potencia neta Braza (6 pies) Pie, pies Galón (4,546 lts.U.K.,3,785 lts.EE.UU.) Medida de 1/8 de litro Caballo de vapor o fuerza Quintal (EE.UU.100 libras = 45,36 kgs; U.K. 112 libras = 50,8 kgs.) Hidrómetro Pulgada (1/12 de pié = 2,54 cm.) Potencia indicada Tonelada de 2.240 libras) Presión media efectiva Presión media Micrómetro Milla Potencia efectiva, potencia útil Potencia nominal Onza (28,35 grs.) (1,16 libras) Cuartillo 1/8 galón Libra Libra de 12 onzas Pirómetro Cuarto de galón Salinómetro Potencia axil, potencia al eje Tonelada de 2.000 libras

Cable Diagram indicator Dynamometer Effective Horse Power (E.H.P.) Fathom Foot, feet Gallon Gill Horse-power Hundredweight Hydrometer Inch Indicated Horse Power (I.H.P.) Long ton Mean effective pressure Mean pressure Micrometer Mile Nett Horse Power (N.H.P.) Nominal Horse Power (N.H.P.) Ounce Pint Pound Pound troy Pyrometer Quart Salinometer Shaft Horse Power (S.H.P.) Short tone 77

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INGLÉS TÉCNICO-MARÍTIMO Steam gauge Stone Tachometer Test-cocks Thermometer Torsiometer Water gauge

Manómetro Peso de 14 libras Tacómetro Grifos de prueba Termómetro Torsiómetro Indicador del nivel de agua

BRAKE HORSE POWER (B.H.P.) or NETT HORSE POWER Power delivered by an engine or motor to the shaft after overcoming all frictional resistances in the engine. To get the Brake Horse Power it is necessary to fit a brake over the flywheel. SHAFT HORSE POWER (S.H.P.) Net power delivered to the propeller shafting after passing through reduction gears, thrust block and other transmission devices. The torsiometer gives the Shaft Horse Power. HORSE POWER (H.P.) Measure of the amount of work which a mechanical device can do in a unit of time. INDICATED HORSE POWER (I.H.P.) Indicated Horse Power is the power developed inside the cylinder, and takes no account of the work that may be lost in overcoming the functional resistance in the engine. This horse-power is deduced from an indicator diagram, which record the pressure in relation to stroke in an engine cylinder at different stages of the work cycle; from it the power developed in the cylinder can be determined. NOMINAL HORSE POWER (N.H.P.) Nominal Horse Power is an obsolete, term with relation with the actual power of an engine, but it is still used in classification of steamers. BRITISH THERMAL UNIT (B.T.U.) The British Thermal Unit is the unit of heat, and is the quantity of heat required to raise the temperature of one pound of water one degree Fahreinheit. PE-IDM.601(B)

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DIAGRAM-INDICATOR The diagram indicator is an instrument used to obtain a diagram showing the variations of pressure in a cylinder through the stroke, and so obtaining the indicated horsepower of the engine and detecting faults in the setting of valves and other faults such as leaky valves and piston rings. The principle of operation consists of a flat sheet attached to an extension of the piston rod, which moves backwards and forwards with it. Connected to the end of the main cylinder is a small cylinder with a piston, and behind the piston is a spring which opposes the steam pressure on the small indicator piston, which will move up and down as the steam pressure varies in the main cylinder. A pencil on the indicator piston-rod marks the sheet which moves to and fro with a travel equal to the piston travel, and so an indicator diagram is drawn. PYROMETER Pyrometers are used when high temperatures have to be registered. Two types in common use are: the mechanical and the electrical. The electrical has the advantage over the mechanical, in that it can show temperatures at points some distance from where the heat exists; for instance the heat in an engine cylinder can be shown on an instrument a distance away from the engine. TORSIOMETER The torsiometer is an instrument which measures the twist over a certain lengt of the shaft, and is used for determining the shaft horse-power developed by an engine. SALINOMETER The salinometer is an instrument to indicate proportion of saline content of water. A common type of salinometer consists of a bulb and graduated stem which is weighted at the bottom to make it float upright in the water. The less dense the water the more it will be immersed and the more dense the higher it will float. The electric salinometer consists of two electrodes immersed in the water at a predetermined distance apart and the electrical resistance provides a measure of the degree of salinity. With the salinometer the condition of the feed water can be determined. A reading of the salinometer must be taken when taking over the watch and frequently dring the watch.

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The thermometer is an instrument for measuring temperature. The ordinary thermometer consists of a graduated glass capilary tube with a bulb containing mercury or alcohol which expands or contracts as the temperature rises or falls. Thermometer are marked with Fahreinheit or centigrade scales. Screw-type thermometers are used to register the temperature of steam and fluids in boilers, tanks, etc. A bulb beyond the thread makes contact with the steam or fluid. They are usually installed on the boiler, steam chest, etc. TACHOMETER A device for measuring speed, especially the speed of a shaft in revolutions per minute. WATER GAUGE The water gauge is an indicator showing the height of water inside a tank or boiler. Measures: Units The systems of weights and measures used in Great Britain and in the United States are in general practically identical, but there are some important differences. For example, the British use the long ton of 2.240 pds. whereas in the United States the short ton of 2.000 pds. is generally used. The U.S. bushel and the gallon are also different from the corresponding British units. In the British system the units of dry measure are the same as these of the liquid measure and include both the gallon and the bushel (equal to 8 gal.). In the United States, however, the two are not the same, the gallon and its subdivisions being used for measurement of liquids, and the bushel and its subdivisions being used to measure dry goods. The U.S. gallon of 231 cu. in. is divided into 4 liquid quarts, or 128 fl.oz. The U.S. bushel of 2.150,42 cu.in. is divided into 32 dry quarts. The British Imperial Gallon is larger than the U.S. gallon, being equal to about 6/5 of U.S. gallon, and is divided into 4 qts. or fl.oz. The British Imperial Bushel is about 3% larger than the U.S. bushel and is divided into 32 qts. Another difference between the two systems of weights and measures is the use of the “stone” as a British unit of weight equal to 14 pds. In Canada the British Imperial units are used, except that the short ton of 2.000 pds. is used instead of the long ton of 2.240 pds., and the stone is not used. PE-IDM.601(B)

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CHAPTER 12 METALLURGY Vocabulary Air furnace Air quenching Alloy Alloy steel Annealing Anodizing Arc furnace Arc welding Ash Babbit metal Bearing bronze Bearing metal Billet Black plate Blacksmith welding Blast furnace Bloom Boiling point Brass Brazing Breaking load Breaking stress Brittle Brittleness Bronze Browned steel Bushing metal Butt welding Carbide Carbon steel Carbonizing Cast Cast iron Casting Cementation Charcoal

Horno de reverbero, de tiro natural. Temple al aire, auto-temple Aleación Acero aleado Recocido Anodizado Horno de arce Soldadura con arco Ceniza Metal antifricción Bronce para cojinetes Metal para cojinetes Palanquilla Chapa sin recubrimiento Soldadura en frío Horno alto Desbaste laminado Punto de ebullición Latón Soldadura fuerte, latonado Carga de rotura Esfuerzo de rotura Frágil Fragilidad Bronce Acero pavonado Metal para cojinete Soldadura a tope Carburo Acero al carbono Cementación Colar, fundir Hierro colado, hierro fundido Pieza obtenida por fundición Cementación Carbón vegetal 83

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INGLÉS TÉCNICO-MARÍTIMO Chilled cast iron Chromate steel Chrome Chrome steel Chromium Chromizing Clay Coal Coating Coke Converter Crack Creep Dead steel Dead annealing Dead-soft steel Die Dip brazing Draw plate Drawing back Drop forging Elastic breakdown Elongation Embrittlement Embrittlement crack Endurance Etching Fatigue limit Fissure Flame cutting Flask Flaw Flux Forge Forging

Hierro colado enfriado rápidamente Acero cromado Cromo Acero al cromo Cromo Cromado Arcilla Carbón Revestimiento Cock Convertidor Grieta Fluencia Acero calmado Recocido a fondo Acero extradulce Molde, matriz Soldadura por inmersión Hilera Revenir Forja con matrices Fatiga Alargamiento Fragilización Grieta de fragilidad Límite de resistencia Ataque Límite de fatiga Fisura Corte con soplete Caja de moldeo Grieta Fundente Forja Forjado en caliente, pieza de forja, trabajo de forja Fundición Fractura Horno Galvanizado Hierro colado, fundición gris

Foundry Fracture Furnace Galvanizing Gray cast-iron PE-IDM.601(B)

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Grinding Gun metal Hammer forging Hardening Hardness Heat, to Heat treatment High-carbon steel High duty High-speed steel High steel Ingot Internal stress Iron Iron ore Journal brass Ladle Lead Light alloy Limestone Loop Low alloy steel Low steel Maleable Medium steel Melt Melting point Metallurgia Mild steel Millind Mold Molding box Molten metal Nickel steel Notch effect Open hearth furnace Open hearth steel

Amolado Bronce de cañón Forja con martillo Endurecimiento Dureza Calentar Tratamiento térmico Acero alto en carbono Buena calidad Acero de corte rápido Acero alto en carbono Lingote Tensión interna Hierro Mineral de hierro Bronce para cojinetes Cuchara para metal fundido Plomo Aleación ligera Caliza Tocho Acero de baja aleación Acero de poco carbono Maleable Acero de proporción media en carbono Fundir Punto de fusión Metalurgia Acero dulce Fresado Molde Caja de moldeo Metal fundido Acero al níquel Efecto de entalladura Horno Martin Siemens, horno de solera Acero obtenido mediante el horno MartinSiemens Acero efervescente Mineral Modelo

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INGLÉS TÉCNICO-MARÍTIMO Peat Pig iron Pit Plain carbon steel Plate Pot furnace Press Pricking Quenching Reagent Rolling Run steel Rust Sand Sand mold Scrap Seam Seam welding Semisteel Shearing strenght Shrinkage Silica Silicon steel Slab Soft quenching Soft solder Soft steel Soldering Spar Spot-welding Stainless steel Steel Steel casting Stove Strain Strength Stress Sulphide Sulphur Tempering Tensile strength PE-IDM.601(B)

Carbón de turba Arrabio Picadura Acero corriente en carbono Plancha Horno de crisol Prensa Punzonado Temple Reactivo Laminación Fundición maleable Herrumbre Arena Molde de arena Chatarra Grieta superficial Soldadura de costura Semiacero Resistencia a la cizalla Contracción Sílice Acero al silicio Desbaste plano de laminación Temple suave Soldadura blanda Acero suave Soldadura blanda Espato fluor Soldadura por puntos Acero inoxidable Acero Acero moldeado Estufa Deformación por exceso de carga Resistencia a la rotura Tensión, esfuerzo Sulfuro Azufre Revenido Resistencia a la tracción 86

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Testing Tin Tin plate Tool steel Torch Toughness Water hardening Water quenching Wearing test Weld Welding Welding flux Welding rod White cast iron Wire drawing Wrought iron Wrought steel

Ensayo Estaño Hojalata Acero para herramientas Soplete Tenacidad Temple en agua Temple en agua Ensayo de desgaste Soldar Soldadura Fundente para soldar Varilla para soldar Fundición blanca Trefilado de alambre Hierro bajo en carbono Acero forjado

Metals used in machinery The material used for the manufacture of a component is dependent upon the mechanical stress and the heat stress to which it is subjected. The components of heat engines and machinery for transmitting power are subjected to high mechanical stress and may also require to resist considerable heat stress. Such components are therefore usually made from steel which has high tensile strength and good heat resistant properties. Steel is allowed with various metals to increase one, or both, of these properties. The non-ferrous metals: copper, brasses, bronzes, etc, are generally associated with components which are lightly stressed but are in contact with sea water, for they are corrosion resistant. Various alloys of comparatively high tensile strength have been produced, however, and these can often be used instead of alloy steels, which are expensive and present some manufacturing difficulties. Although aluminium in its pure state is not often used, aluminium alloys are being increasingly used in machinery systems. When alloyed with nickel, copper, magnesium and silicon, a very good weight/strength ratio can be obtained. Most aluminium alloys are corrosin resistant, provided that in use their coupling with copper-based alloys is avoided. Rotary and reciprocating components are subjected to high stresses and are usually made of carbon steel or alloy steel. Examples: Steam turbines: rotor shafts, rotor forgings, gearing. 87

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Steam reciprocating engines: pistons, piston rods, connecting rods, crankshafts, valve operating gear. Diesel engines: connecting rods, crankshafts, valve and valve operating gear, gearwheels. Gas turbines: compressor shafts, compressor discs, turbine shafts, gearing. When moving parts are also subjected to high temperaturre and erosive effects they are made of stainless iron (for moderate stresses) or stainless chromium steel (for higher stresses). Examples: Steam turbine blading and pump impellers. For resistance against severe corrosive effects, the austenitic stainless steels 18/8 chromium nickel alloys are used. Non-moving parts, when subjected to high tensile and bending stress, are also made from steel. Examples: All forms of high pressure piping for steam, and furnace fuel-oil, and the flanges Boilers drums, boiler tubes. When exposed to high temperature and erosive effects of superheated steam they are made from stainless chromium steel. Examples: Superheated steam valves and valve spindles. Monel metal, a nickel copper alloy may be used in this range. When subjected to high gas temperatures, above 850º F, a creep-resisting molybdenum steel alloy is employed. ”Creep” is the permanent growth of a metal after subjection to extreme heat. Examples: Gas turbine nozzles and guide blades. When resistance to furnace and burning temperatures is required without the protection of brickwork, a heat-resisting steel alloy is used which contains silicon and tungsten. Examples: Gas turbine combustion tubes and fittings. Boiler superheater tube supports. Castings subjected to high pressure or high temperature are made of cast steel. Examples: H.P. turbine casings, high pressure valve boxes. Cast iron Although this metal has high compressive strength, the tensile strength is very low,and themetal is liable to fracture under shock. It is not therefore in general use for machinery. But it is easily cast into intrincate shapes, and affords a good lubricating surface when machined. When cast under special conditions to produce a close grain, including sometimes a trace of

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alloy metal, it is used for lightly stressed components which are well supported to avoid fracture. Examples: Piston rings, slide valves, cylinder heads of small internal combustion engines, cylinder blocks of small internal combustion engines. Non-ferrous metals and alloys These metals: copper, brass, bronze, etc., have high resistance to sea water corrosion, but generally have low tensile strength. They are used extensively in the manufacture of lightly stressed components in contact with sea water. Copper: Very ductile, very high relative conductivity. Cupro.nickel: A copper nickel alloy which has high resistance to erosion. Examples: Condenser tubes, cooler tubes. Brass: A copper and zinc alloy, easily cast and machined. Examples: H.T. brass, propellers. Bronze: A copper and tin alloy which when further alloyed with other metals to produce gunmetal, aluminium bronze, phospher bronze, nickel bronze, etc., has a comparatively high tensile strength while retaining the non-corrosive property. Examples: Bearings bushes, shaft sleeves. All forms of castings in contact with sea-water. Aluminium This is one of the lightest metals known and has high relative conductivity. It is not generally used in pure state, but is alloyed with silicon for common use. Examples: Lightly stressed castings for all forms of ancillaries. When alloyed with copper, nickel, magnesium, and silicon to produce “Y” alloy, the tensile strength and resistance to corrosion is much improved, and the high relative conductivity is retained. This alloy is therefore used very extensively where reduction in weight combined with rapid dispersal of heat is required. Whitemetal This is a tin, copper, zinc and antimony alloy of very good anti-friction properties and is used very widely for bearings. It has a low melting point and must be continuously supplied with lubrication to prevent the collapse of the material. Engine are usually in the form of a shell of steel or bronze which is "whitemetalled" internally.

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INGLÉS TÉCNICO-MARÍTIMO Technical Vocabulary Alloy Alloy steel Aluminium Aluminium alloy Ancillaries Austenitic stainless steel Bearing bushes Bending stress Boiler drum Boiler tube Brass Brickwork Bronze Carbon steel Cast Casting Cast iron

Aleación Acero aleado Aluminio Aleación de aluminio Dependientes, secundarios Acero inoxidable austenítico Revestimiento de cojinetes Esfuerzo de flexión, dobladura Colector de caldera Tubo de caldera Latón Enladrillado Bronce Acero al carbono Colar, pieza obtenida por fundición Colada, pieza de fundición Hierro colado, hierro fundido, fundición de Hierro, arrabio Acero fundido, acero colado, acero moldeado Níquel cromado, cromoníquel Cromo Debilitar Compresor Eje del compresor Conductividad Bielas Cobre Corrosión Cigüeñal Fluencia Resistencia a la fluencia Cuproníquel Bloque del cilindro Culata del cilindro Dúctil Brida Pieza forjada Rueda dentada

Cast steel Chromium nickel Chromium Collapse Compressor Compressor shaft Conductivity Connecting rods Copper Corrosion Crankshaft Creep Creep resistance Cupro nickel Cylinder block Cylinder head Ductile Flange Forgings Gearwheel PE-IDM.601(B)

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Gearing Growth Guide blades Gunmetal Heat treatment (H.T.) Heat engines Heat stress Magnesium Mechanical stress Molibdenum Monel metal Nickel Nickel bronze Non-ferrous metals Non-metallic materials Phospher bronze Piping Piston Piston rod Pump impellers Rotor forging Rotor shaft Silicon Stainless steel Steel Steel alloys Steam turbine Steam reciprocating engine Shaft sleeves Stress Strength Superheated steam Superheated steam valves Tin alloy Tungsten Valve operating gear Valve spindles Weight strength Whitemetal

Engranaje Aumento Paletas directrices Bronce de cañón Tratamiento térmico Máquinas térmicas Resistencia al calor Magnesio Resistencia al calor Molibdeno Metal monel Níquel Cuproníquel Metales no ferrosos Materiales no metálicos Bronce fosforoso Tubería Embolo Vástago Impulsores de la bomba Rotor Eje del rotor Silicio Acero inoxidable Acero Aleaciones de acero Turbina de vapor Máquina alternativa de vapor Manguitos del eje Esfuerzo Resistencia Vapor recalentado Válvulas de vapor recalentado Aleación de estaño Tungsteno Válvula accionada por engranaje Ejes de válvula Resistencia al peso Metal blanco

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INGLÉS TÉCNICO-MARÍTIMO MACHINE TOOLS Vocabulary Automatic lathe Back center Bad plate Band saw Bays Benches Blades Blast machine Boring Boring-bar Boring cutter Broach, to Broaching machine Buffin machine Calking machine Casing Circular saw Clamp Clamp dog Center bit Centre rest Cone pulleys Countershink, to Countershink bit Corrugated iron Cutter Cutting tool Change gear Chasing Chuck Chuck later Dead centre Direct current Distribution board Drilling machine Drill-press Drills PE-IDM.601(B)

Torno automático Contrapunta Banco de fundición Sierra continua Naves (talleres) Bancos de trabajo Álabes, paletas Máquina sopladora Taladrado, agujereado Barra porta-barrena Cuchilla de taladro Escariar, mandrilar Mandriladora, escariadora Bruñidora mecánica Retacadora Envolvente Sierra circular Mordaza Brida de arrastre Broca de centrar Luneta Polea escalonada Avellanar Avellanador, broca de avellanar Hierro ondulado Cuchilla Cuchilla Cambio de velocidades por engranaje Fileteado Plato Torno al aire Contrapunta, punta del cabezal móvil Corriente continua Cuadro de derivación Taladradora Taladradora Brocas 92

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Drill chuck Engine lathe Erecting shop Expansion reamer Face lathe Face plate Fitting Follower rest Footstock Foreman´s office Forging Frame Gear wheel Grinder Grinding machine Grinding wheel Grindstone Hand trimmer Head stock Helical gear High speed cutter Horizontal milling machine Independent chuck Inserted blade cutter Jaw Jaw lathe chuck Jib crane Knurling tool Lathe Lathe bed Lathe centre Lathe chuck Lathe dog Lathe head Lead saw Machine shop Mill, to Milling cutter Milling machine Milling tool Millstone

Portabrocas Torno paralelo o de puntas Taller de montaje Escariador ajustable Torno al aire Plato portapiezas, plato Accesorio Luneta móvil Contrapunta Oficina del Capataz Forja Bastidor Rueda dentada Rectificador Máquina de esmerilar Muela Muela Recortadora de mano Cabezal Engranaje helicoidal Cuchilla de gran velocidad Fresadora horizontal Plato de mordazas independientes Fresa con cuchillas insertadas Mordaza Mordaza de plato de torno Grúa de pescante Herramienta moleteadora Torno Bancada Punta de torno Plato de cabezal Perno, mordaza Cabezal de torno Sierra de cinta Taller mecánico Fresar Fresa Fresadora Fresa Muela 93

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INGLÉS TÉCNICO-MARÍTIMO Morse taper Mortise Mortising machine Mortising Natural draught Pattern shop Pattern maker Pillar drilling machine Pipe bending machine Plane, to Planer Planning machine Press Profile cutter Punchin machine Radial drilling machine Ram Reciprocal saw Ream, to Repetition lathe Riveting machine Rolling Sand papering machine Sawing Sawing machine Screw cutting machine Shaper Shape, to Shavings Side cutter Side milling cutter Slide Smithy Spindle Spindlehead Steady Straight reamer Straight turning Stranded Surfacing Tail stock PE-IDM.601(B)

Ahusado Morse Muesca Mortajadora o escopleadora Mortajado, escopleado Tiro natural Taller de modelado Modelista Taladradora de columna Máquina curva tubos Cepillar Cepilladora Cepilladora Prensa Fresa perfiladora Punzonadora Taladradora radial Corredera Sierra alternativa Escariar Torno de repeteción Remachadora Laminado Lijadora Aserrado Sierra mecánica Torno de filetear Limadora Perfilar Virutas Fresa de disco Fresa de corte lateral Guía Herrería Husillo Portahusillo Luneta Escariador cilíndrico Cilindrado Trefilado Acabado Contrapunta 94

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Tapered Tapper reamer Tapping Tapping machine Thread, to Threaded Tool box Tool carriage Torsion meter Travelling crane Turning Turret lathe Tuyeres Universal chuck Works

Cónico Escariador Cónico Roscado Máquina de taladrar tubería Filetear Fileteado Carro porta-herramientas Carro porta-herramientas Indicador de torsión Grúa corrediza Torneado Torno revólver Toberas Plato universal Fábrica

MACHINE TOOLS Machine tools are mechanical apparatus for doing work with a tool. The main machine tools are: • Engine lathe • Drill press • Milling machine • Grinder • Shaper ENGINE LATHE The lathe is a machine tool used for shaping cylindrical surface by the action of stationary cutting tools which are pressed against the work while it is rotating The esential parts of a lathe are: • Bed plate Bancada • Headstock Cabezal • Tail stock Contrapunta • Tool carriage Carro porta herramientas The headstock houses a rotary shaft and its driving mechanism attached to the headstock is the chuck which holds the work. The tailstock may be moved to any position on the bed and clamped in it, it is used to support the work.

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The drill press is a machine-tool for drilling holes in metal with a rotating drill. It consists of a work table on which the work is clamped and a power rotated vertical spindle above the table which carries the drill tool. The drill press most known is the pillar drilling machine, its essential parts are: • Frame Bastidor • Column Columna • Table Mesa • Base Base • Table arm and gear Brazo de la base y mando de movimiento • Spindle sleeve Husillo portabrocas • Hand feed wheel Mando de movimiento avante • Motor Motor MILLING MACHINE This tool is not found in the machine shop of merchant vessels. It is used for working metal with a rotary toothed-cutter, as a moving table carries the work against the cutter. The work is rigidly supported in the table. GRINDING MACHINE The grinding machine in the ship´s machine shop is usually of the double type, having two grinding wheels and the driving motor between them. SHAPER A machine-tool for making straight cuts with a sharpened tool held on a reciprocating ram. The work is supported on an adjustable table. On the head of the ram is the tool holder.

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Vocabulary Adjustable wrench Anvil Ball hammer Beam clamp Bearing scraper Bench vise Box wrench Bolt clippers Breast drill Caliper Cape chisel Cant file Center punch Cold chisel Combination square Copper face hammer Crow bar Chain pipe wrench Defletometer Die set Die stock Divider Double end scapper Double end wrench Drive pin punch File handle Flat file Flat nose pliers Hack saw blade Hack saw frame Half round file Hand reamer Hand tap Hand vise Hatchet Hickory mallet Inside calipers

Llave universal Yunque Martillo de bola Mordaza de bao Rasqueta para ajuste Tornillo de banco portátil Llave de vaso, llave de tubo Cortador de pernos Berbiquí de pecho Calibre o pié de rey Buril Lima triangular Granete Cincel o cortafrío Escuadra universal Mazo de cobre Pié de cabra Llave para tubos de cadena Flexímetro Juego de matrices, cojinetes, terrajas Potacojinetes o porta terraja Compás de puntas Rasqueta de doble cabeza Llave fija de dos bocas Botador Mango de lima Lima plana Alicates de punta plana Hoja de sierra para metales Armazón de sierra Lima de media caña Escariador de mano Macho de terraja a mano Tornillo de apretar a mano Hacha pequeña Mazo de madera Compás de gruesos interiores 99

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INGLÉS TÉCNICO-MARÍTIMO Lead hammer Linoleum knife Mallet Micrometer caliper Monkey wrench Nippers Outside calipers Pipe wrench Point box wrench Portable electric drill Ratchet Round file Round nose plier Round punch Shave hook Scaling hammer Scissors Srewdriver Screw tap Single end wrench Sledge hammer Snips Socket wrench Soldering iron Speed indicator Square file Steel tap Steel rule Steel square Surface gage Tap Tap wrench Thickness gages Vise Wire gage Wire scratch brush Wrench

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Mazo de plomo Cuchilla para cortar empaquetadura Mazo Palmer o micrómetro para exteriores Llave inglesa Tenazas Compás de gruesos exteriores Llave para tubos Llave de estrella Taladradora eléctrica portable Catraca o chicharra Lima redonda Alicate de punta redonda Sacabocados Rasqueta para ajuste Piqueta para óxido Tijeras Destornillador Macho de terraja Llave fija de una cabeza Mandarria Tijeras para cortar plancha Llave de tuerca de boca tubular, de cubo Soldador Contador de revoluciones Lima cuadrada Cinta métrica de acero Regla de acero Escuadra ordinaria de acero Gramil de trazador Macho de terraja Bandeador o volteador Juego de tientas o galgas Tornillo de banco Galga para medir espesores de alambre Cepillo de alambre Llave de tuercas

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Parsons Marine Turbine Works at Wallsend (Extract from a report published in 1905) The Marine Works at Wallsend-on-Tyne were organised in 1897, thirteen years after the first turbine was manufactured for driving electric generators. The practical demonstration of the marine turbine was with the construction in 1894 of the first turbine steamer, the “Turbinia”. The success attained encouraged the formation of the new company, “The Parsons Marine Steam Turbine Company Limited”. This company established the marine works at Wallsend-on-Tyne, at which were designed and manufactured all marine turbines made up to the year 1904. This establishment called “The Turbinia Works” was situated four miles from Newcastle, on the bank of the River Tyne, embraced an area of 23 acres and a river frontage of 900 ft., with a wharf for the mooring of vessels during the period of fitting machinery on board. The workshops include machine shops, blading shops, test house, pattern shop, copper smithy, brass foundry, smithy, extensive stores and an experimental deparment. Electric power is of course, used throughout the works, and it was only fitting that the current should be taken from the adjacent “Carville Power Station” where the Parson Turbo Generator is extensively applied and efficiently run. There is in the works a large steam producing plant, including one cylindrical and two water tube boilers for use in testing the turbines before leaving the works. The tools in the pattern shop include two planing machines, circular, universal and band saws, spindle machine, mortice, and drilling machine, four lathes, a comprehensive wood-working machine, sand-papering machine and hand trimmers. Benches with special vices have been arranged for about one hundred-pattern makers. Adjoining there is a store about 100 ft.long and 40 ft.wide, built entirely of corrugated iron as a prevention against fire. The brass foundry is served by a 10-ton travelling crane. There are twelve fires, with a tall chimney to give a good natural draught. The copper shop has nine brazing forges, supplied with blast from a shot´s blower. Compressed air pipes are laid throughout the shop in connection with portable, pneumatic, calking and riveting machines. The other appliances include a pneumatic hammer, a shearing and punching machine, an hydraulic pipe-bending machine, circular saws, and a drilling machine.. A 5-ton travelling crane serves the part of the shop where the heavier items are worked, and in addition, jib cranes swing over all the fires. In the smithy forgings up to 3 tons are produced with the use of special furnaces and a large power-driven pneumatic hammer. There are also a number of smith´s hearts with water cooled tuyeres for finishing small works.

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The bays of the machine and erecting shop have the following main tools: a large boring machine, wich will take casings up to 16 ft. in diameter and 50 ft. in length. There is also a large lathe for turning rotors. The planing of large cylinders casings is done on a heavy vertical and horizontal planner. There is a 90-in. centre duplex sliding surfacing, and a screw-cutting lathe to take a job 55 ft. 6 in. between centres, and to swing 15 ft. over the bed and sliding carriage. This lathe is driven by a variable speed direct current motor. There are four-speed cone pulleys. A face plate chuck 12 ft. diameter with external gearings provided with four loose steel jaws on the front. Next to this lathe is a horizontal boring machine, designed especially for boring out and grooving turbine casings. Beyond this boring machine is a new vertical and horizontal planing machine, a double horizontal drilling, boring, tapping, milling and studding machine. There are also in this bay two shafting lathes and machine for calibrating torsion motors, for measuring shaft horse-power. In the centre bay are also the tool shop and tool store. In the tool shop are benches and vices, as well as a screw-cutting lathe, a milling machine, several grinding machines, a large twist drill grinder to finish drills up to 4 in. in diameter, and several small drilling machines. Above the tool store is the foreman´s office. The southern end of the three bays is devoted to the erecting of rotors and casings; the blading of them, and the water and steam testing of the completed turbines. There are two works devoted entirely to the work of forming the blades to the correct size, the blades are cut by a patent blade press and the holes in the roots of the blades are drilled in small special drilling machines. A special test house is used for steaming and testing the smaller sized turbines. A 30ton travelling crane runs the whole length of the shop. At one end of this building are the three phase and direct-current distribution boards, and a 100-kilowatt Vickers mootor generator. The work at Wallsend has been associated chiefly with the experimental testing and calculation of blading, blade strength, and blade capacities in marine turbines. There is also apparatus greatest effect in a given size of cooler. Thus the efficiency of machinery wheter by land or marine purposes can be tested in the experimental department of the Heaten from the generation of the steam to its conversion to work in any form. This record, demonstrates the possession by the firm of a complete knowledge of the problems to be solved and there is justification for the hope that still better results with the turbines will reached in the future.

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CHAPTER 13 ELECTRICITY Vocabulary Accumulator Alternating current Alternator Ammeter Ampere Amplitude Anode Arc Armature Battery Braided cable Cathode Cell Circuit Circuit breaker Collector Conductor Connection Cut-out Dielectric Dry cell Earth line Electric bell Electric circuit Electrolyte Electromagnet Electromotive force Electroscope Filament Flexible cord Fuse Galvanometer Generator High frequency current Induced current

Acumulador Corriente alterna Alternador Amperímetro Amperio Amplitud Ánodo Arco Inducido (imán), armadura (dinamo) Batería Cable trenzado Cátodo Pila Circuito Disyuntor, interruptor Colector, toma de corriente Conductor Conexión Disyuntor Dieléctrico Pila seca Línea de tierra Timbre eléctrico Circuito eléctrico Electrolítico Electroimán Fuerza electromotriz Electroscopio Filamento Cordón flexible Fusible Galvanómetro Generador Corriente de alta frecuencia Corriente inducida 105

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INGLÉS TÉCNICO-MARÍTIMO Inductor In series Insulator Ion Joint Lamp Lead Live Magnetic field Mains Moving iron ammeter Moving coil ammeter Negative electrode Negative pole Parallel series connection Phase Plug Polarization Pole Positive electrode Positive pole Primary cell Resistance Rheostat Series wound Self induction Secondary Single phase-generator Shunt Shunt circuit Socket Solenoid Spark Switch Switch board Terminals Three-phase generator Two-phase generator Voltage Voltemeter Wavelength PE-IDM.601(B)

Inductor, rotor En serie Aislador, aislante Ion Empalme Lámpara Alambre aislado de conexión Con corriente, activo Campo magnético Red de suministro, de distribución Amperímetro de núcleo giratorio Amperímetro de bobina giratoria Electrodo negativo Polo negativo Acoplamiento en series paralelas Fase Enchufe Polarización Polo Electrodo positivo Polo positivo Pila primaria Resistencia Reostato Arrollado en serie Auto-inducción Secundario Alternador monofásico Derivación Circuito derivado Casquillo Solenoide Chispa Interruptor Cuadro de distribución Bornes Alternador trifásico Alternador bifásico Voltaje, tensión Voltímetro Longitud de onda 106

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Winding Wire Yoke

Devanado, bobinado Alambre Culata

Electricity and production of a current Electricity is a form of energy; that is, capable of doing work. Scientists have evolved a modern theory called the “electron theory” which explains the nature of electricity, but it will be sufficient for our purpose if we understood how an electric current is produced and what it can do. Electric current is produced in two ways, viz; by chemical action in a cell or battery, or by magnetic means in a dynamo or generator. There are three general effects caused by electric current. These are: magnetic, heating and chemical effects. If a wire carrying a current of electricity is brought near a small compass needle, the needle will be deflected from the magnetic meridian, i.e., it will cease to point to the magnetic pole. The deflection will depend upon the direction of the current flowing in the wire and on the position of the wire relative to the needle. This is one example of the magnetic effect or influence of a current. After some time has clapsed it will be also discovered that the wire has become heated by the passage of the current throught it. Thus the phisical properties of the wire have been changed when a current flows in it, although we cannot actually see the current itself. The chemical effect is observed when an electric current is passed through certain solutions or compound liquids. These liquids are found to descompose into their separate constituents under the influence of the current. The four principal units which are used to compare electric currents define their pressure, strength, the resistance set up against theeir flow by the material through which the currents are passing, and power developed. These units are called: the volt, ampere, ohm and watt respectively. The volt is the electrical unit of pressure or electromotive force and is the pressure necessary to cause a current of one ampere to flow along a wire whese resitance is one ohm. The ampere is the electrical unit of current strength and is defined by the chemical effect of a current on a solution of nitrate of silverin water, deposits silver at the rate of 0,001118 grammes per second. The ohm is the electrical unit of resistance to current flow, and is defined as the resistance set-up by a column of mercury 106,3 cms long and one square millimetre in cross sectional area, when at the temperature of melting ice.

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The watt is the electrical unit of power and is the power developed by a current of one ampere at a pressure of one volt.. Magnetic fields Ampere discovered in 1820 that two parallel current-carrying conductors were attracted toward each other if the currents were flowing in the same direction, and repelled if the currents flowed in the opposite direction. Eleven years later, Faraday discovered that a changing current in one conductor would induce a voltage in a parallel conductor and cause a current to flow if the parallel conductor formed a closed loop. We know that electrical currents consist of moving charges and that the actions described above are the results of charges moving or being accelerated in the wires. The phenomenon of forces between accelerated charges will be considered under the heading of induced voltage. Some of the force phenomena between moving charges can be handled quantitatively by formulas that give the force between currents or current elements directly, but in general it will be much more effective to consider that one group of moving charges produces a magnetic field, which reacts upon another group of moving charges or another current. In general, no other solution is available when the conductors carrying the currents are surrounded, or in the near vicinity of iron or other so-called “magnetic-material.” Let us now consider the development of the concepts of magnetism, through which the force action between the two wires may be explained. The current in a conductor is considered to set up an action of some nature in a closed path around the conductor. This action is called a “magnetomotive force.” The magnetomotive force, in turn, produces another quantity called “field intensity,” which exists at all points around the wire and sets up another quantity called “flux density” at the corresponding points. Both flux density and field density are vector quantities, i.e., they have both magnitude and direction. The term “flux density” suggests the term “flux,” since density implies the ratio of some quantity to length, area, or volume. Flux, or more definitely, magnetic flux, is defined as the integral of the flux density taken over the area through wich the flux passes. The space in which the magnetic quantities, magnetomotive force, field intensity, flux density, and flux, are said to exist is called a “magnetic field”. All off the above magnetic quantities are useful in calculating force between moving or accelerating charges in various situations. However, the quantity flux density is the only one needed in connection with the force between two parallel wires. One of the currentcarrying wires is considered to produce a flux density in the surrounding space, and the other current-carrying wire is said to experience a side thrust because of its location in this magnetic field. A beginning concept of magnetism may be obtained from the above discussion, but before any of the quantities can be used analytically, it will be necessary to define the quantities and their corresponding units rigorously with the aid of defining equations. PE-IDM.601(B)

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CHAPTER 14 ELECTRIC ENGINES Vocabulary Air gap Alternating current generator Alternating current motor Alternator Armature Armature winding Bearing Bipolar Bipolar dynamo Brush Brush holder Carbon brushes Coil Commutator Compound dynamo Compound winding Core Direct current generator Direct current motor Double magnet Drum armature Electromagnet Electrostatic generator External circuit Fields coils Fields magnets Four pole dynamo High frequency alternator Inductor Induction motor In parallel In series Iron core Loops of wire Magneto Magnets core Permanent magnet alternator Poles Polyphasic Rheostat

Entrehierro Dínamo de corriente alterna Motor de corriente alterna Alternador Inducido Devanado de inducido Cojinete Bipolar Dínamo bipolar Escobilla Porta escobilla Escobillas de carbón Bobina Colector Dínamo de excitación compuesta Bobinado doble, mixto Núcleo Dínamo de corriente continua Motor de corriente continua Imán doble Inducido de tambor Electroimán Generador electrostático Circuito externo Bobinas de campo Inductor Dínamo tetrapolar Alternador de alta frecuencia Inductor Motor de inducción Acoplamiento en paralelo Acoplamiento en serie Núcleo de hierro Espiras Máquina magnetoeléctrica, magneto Núcleo del imán Alternador de imán permanente Polos Polifásico Reostato 109

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INGLÉS TÉCNICO-MARÍTIMO Ring armature Rotating armature Rotor Self excited dynamo Separately excited dynamo Series dynamo Series wound Shunt Shunt dynamo Synchronous motor Single phase Single magnet Sleeve Slip rings Soft iron discs Spindle Stator Starting rheostat Turbo-alternator Turbo-dynamo Transformer Winding Wire gauze brushed Yoke

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Inducido de anillo Inducido giratorio Rotor Dínamo de autoexcitación Dínamo de excitación independiente Dínamo con excitación en serie Devanado en serie Derivación Dínamo con excitación shunt Motor sincrónico Monofásica De un imán Manguito Anillos de frotamiento Discos de hierro dulce Husillo Estator, inducido de un alternador Reostato de arranque Turbo alternador Turbo dínamo Transformador Devanado Escobilla de tela metálica Culata

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Physical aspects of electromechanical energy conversion Any electromechanical energy-conversion mechanism is a coupling device between the eletrical and the mechanical systems utilizing the medium of a magnetic or an electric field. The field must react on the electrical system to produce a voltage and hence a current and on the mechanical system to produce a force or torque and hence linear or rotary motion. Generators and motors utilize the magnetic field as an intermediary and take advantage of Faraday´s law of induction, viz., that an induced voltage which is proportional to the time rate of change of flux linkages appears in a winding. Intimately associated with this effect, and related to it through the conservation-of-energy principle, is the production of a force on a current-carrying conductor in a magnetic field; the latter effect may alternatively be regarded as a force proportional to the angular rate of change of flux linkages with a winding. The two effects are present in both generators and motors, a statement wich simply emphasizes the inherent reversibility of energy-conversion processes. The main distinction between generators and motors, therefore, is the direction of energy flow. The energy irreversibly converted to heat plays no basic role in the conversion process, although the presence of losses must be accounted for in the final formulation of performance theories. Among the essential parts of almost every type of generator and motor are two sets of windings wound on, or embedded in slots in, iron cores. The primary function of one set, the field winding, is the establishment of a magnetic field in the machine. The other set, the armature winding, is the one in which the emf of counter emf of rotation is induced; currents in it are intimately related to the torque or counter torque produced. Thus, the words fields and armature are functional descriptions of the windings; the words stator and rotor describe only their location. Structural considerations (and the necessity for commutation in d-c machines) determine the winding locations in individual machine types. Three principal types of machines accordingly appear: synchronous machines, with direct current in one winding, the field winding, and alternating current available from or impressed at the terminals of the other winding; d-c machines, with direct current not only in the field winding but also available from or impressed on the terminals of the other winding; and induction machines (together with a-c commutator machines such as the a-c series motor), with alternating currents in both windings. All three types are capable of generator and motor action, but the last is rarely used commercially for genetor action. Certain conditions must be satisfied for successful energy conversion, one of which is that magnetic fields produced by the two sets of windings must have the same number of poles. The action of specific machines can be examined from the Blv, Bli viewpoints or from the viewpoint of the component magnetic fields of the two sets of windings trying to align themselves. The fundamental operating principles of all electromagnetic rotating machines are thus essentially the same. As might be expected from inspection of the individual structural details and electrical interconnections, the details of analysis for synchronous, d-c, and induction

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machines will follow diverging branches on the basic trunk. The general strategy underlying analysis, however, is the same for all types. The quantities of primary interest in machinery analysis are generated and terminal voltages, currents, torques, and speeds. The two basic relations for any machine are one for generated voltage in terms of flux density (or flux per pole) and speed, and one for electromagnetic torque in terms of flux density (or flux per pole) and current. With these two relations and the principles of electric-circuit theory and mechanics, any desired operating conditions can be quantitatively investigated. The general strategy of steady-state machinery analysis as it will be carried out in later chapters can be summarized briefly in the following four steps. 1. Obtain from Faraday´s law an expression for generated emf or counter emf. This evaluation requires knowledge of the flux-density waveform in the machine and hence demands examination of the flux distribution. 2. Investigate and include factors causing difference between generated emf and terminal voltage under load. One such factor is resistance of the armature winding. Another condition which must be borne in mind is that the armature winding also creates a component magnetic field, and the flux-linkage bookeeping must be complete in this respect to yield the correct terminal voltage. This effect may be included in the evaluation of emf in the first step, or it may be made part of the second step; analytical convenience is the deciding point. These factors are usually represented by the parameters of equivalent electric circuits. Their evaluation again requires knowledge of flux distribution, with emphasis on that for the armature. The equivalent of the foregoing two steps, plus accounting for magnetic core losses, applies also to the transformer and constitutes the basis of its analysis. 3. Obtain an expression for electromagnetic torque or counter torque. In general, the relation may be established through any of four approaches: a. The energy-conversion principle may be applied. When the rotational emf is evaluated in the first step, the electromagnetic power created by it in conjuction with the armature current may be formulated. This power may be equated to that created by the electromagnetic torque in conjuction with the speed. b. The Bli relation may be used for individual conductor torque, followed by summation over the entire armature winding. Knowledge of flux distribution is evidently required. The torque may be evaluated from the angular rate of change of flux linkages with the armature winding. Again knowledge of flux distribution is required.

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c. The torque may be evaluated from field-energy considerations. 4. Appropriately include machine losses. Ordinarily such inclusion is accomplished by taking account of i²r losses in evaluating electric powers, and of mechanical losses together with hysteresis and eddy-current losses in evaluating mechanical powers. The general objetive for each machine is to obtain equivalent circuits so that the techniques of circuit theory become available for the investigation of energy-conversion phenomena. In general, all four methods listed for evaluation of electromagnetic torque may be applied to the basic machine types. wHile these methods all yield the same results, the processes of applying the methods lead to different degrees and shades of insight into machinery fundamentals. Expediency is also a consideration, for some methods may lead more directly to the desired results in a specific case. The first method leads directly and easily to a result but gives almost no insight into how torque is produced. It says, in effect, that if the machine works, a certain relation must be satisfied. The second method constitutes a more careful examination into the details of torque production in terms of the forces on current-carrying conductors in magnetic fields; as such, it answers morefully the question of how machines work. Since the torque relation is derivable from Faraday´s law and energy conservation in constant-field-energy machines, the second method is the equivalent of the first, but it is applied at more nearly a basic level. This torque relation is readily applicable only to certain electromagnetic machines, however, and therefore the second method does not reveal the fundamental aspects common to all forms of rotating electromagnetic machines. The fourth method is the most fundamental of the approaches but also the most difficult to apply. It is based on a relation applicable to all electromechanical energyconversion devices. D-C Machines The basic factors determining the behavior of d-c machines differ in two important rrespects from those in the induction and synchronous machines: the torque angle is fixed by the brush axis, normally at the optimum value of 90°; and, as viewed from the brushes, the d-c values of generated emf and terminal voltage differ only by the voltage drop in the armature resistance. Variation of electromagnetic torque is therefore determined only by variation of the rotor and stator field strengths, and the variations in generated or terminal voltage may readily be traced from similar considerations. Variation of rotor and stator field strength with changing load depends on the method of connecting the field or stator circuit. In the shunt motor the stator or field current is determined by the impressed voltage and the field resistance and is independent of motor load. The flux per stator pole is then very nearly constant in normal operation. (It may decrease slightly with load because of a usually small demagnetizing effect of increased armature current). Consequently, increased torque 115

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must be accompanied by a very nearly proportionalincrease in armature mmf and armature current and hence by a small decrease in counter emf to allow this increased current through the small armature resistance. Since counter emf is determined by flux and speed. Like the squirrel-cage induction motor, the shunt motor is substantially a constant-speed motor having about 5 per cent drop in speed from no load to full load. Starting torque and maximum torque are limited by the armature current that can be commutated successfully. An outstanding advantage of the shunt motor is ease of speed control. With a rheostat in the shunt-field circuit, the field current and flux per pole may be varied at will, and variation of flux causes the inverse variation of speed to maintain counter emf approximately equal to the impressed terminal voltage. A maximum speed range of about 4 or 5 to1 may be obtained by this method, the limitation again being commutating conditions. By variation of the impresses armature voltage, very wide speed ranges may be obtained. In the series motor increase in load is accompanied by increases in the armature current and mmf and the stator field flux (provided the iron is not completely saturated). Because flux increases with load, speed must drop in order to maintain the balance between impressed voltage and counter emf; moreover, the increase in armature current caused by increased torque is smaller than in the shunt motor because of the increased flux. The series motor is therefore a varying-speed motor with a markedly drooping speed-load. For applications requiring heavy torque overloads, this characteristic is particularly advantageous because the corresponding power overloads are held to more reasonable values by the associated speed drops. Very favorable starting characteristics also result from the increase in flux with increased armature current. In the compound motor the series field may be connected either cumulatively, so that its mmf adds to that of the shunt field, or differentially, so that it opposes. The differential connection is very rarely used. A cumulatively compounded motor will have a speed-load characteristic intermediate between those of a shunt and a series motor, the drop of speed with load depending on the relative number of amper-turns in the shunt and series fields. It does not have the disadvantage of very high light-load speed associated with a series motor, but it retains to a considerable degree the advantages of series excitation. In a d-c motor, the electromagnetic torque is, of course, in the direction of rotation of the armature. The voltage Ea generated in the armature is smaller than the terminal voltage. For operation as a generator, Ea is larger than the terminal voltage, and the relative direction of current through the armature winding is reversed. Because of this reversal, both the armature mmf and the electromagnetic torque reverse, the latter becoming a counter torque opposing rotation. If the machine were connected to a d-c system capable of either absorbing or supplying power, it would supply power to that system when it was driven so that the generated voltage Ea exceeded the terminal voltage. If the mechanical torque were removed, the armature would slow down under the influence of the counter electromagnetic torque until Ea became smaller than the terminal voltage. Reversal of the electromagnetic torque and PE-IDM.601(B)

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steady operation as a motor would follow, with the electromagnetic torque just sufficient to overcome rotational losses. Any of the three excitation methods may also be used for generation. Such generators are called self-excited generators and require residual magnetism in the iron core for the initial appearance of voltage. In addition, the field may be separately excited from an external d-c source. Because constant-voltage power systems are the rule, series generators are very seldom used. Normally, an overcompounded generator is operated with its no-load voltage set at the rated value and hence with a greater full-load voltage, the increment compensating for increased resistance drop in the feeder between the generator terminals and the load. If the series field is so adjusted that full-load and no-loaad voltages are equal, the generator is flatcompounded; if the full-load voltage is lower, it is undercompounded. Synchronous Machines A synchronous machine is an a-c machine whose speed under steady-state conditions is proportional to the frequency of the the current in its armature. At synchronous speed, the rotating magnetic field created by the armature currents travels at the same speed as the field created by the field current, and a steady torque results. Stripped down to its essentials, the workings of a symmetrical polyphase sybchronous machine are rather simple. The d-c excited field winding creates a magnetic field rotating with the rotor. Balanced, polyphase armature currents also create a component magnetic field which rotates around the air gap, travelling through a mechanical angle equal to the angle subtended by two adjacent poles in a time corresponding to one cycle. If the rotor is turning at this speed, the component stator and rotor fields are stationary with respect to each other and a steady torque is produced by their interaction. The resultant air-gap flux is produced by the combined effect of the field and armature curents. A synchronous machine has two outstanding characteristics: (1) the constancy of its speed when operated at constant frequency, and (2) its ability to accommodate itself to operation over a wide range of power factor. The first characteristic is a result of the relation between the speed of the rotating magnetic field produced by its armature currents and the frequency of these currents. Only at this speed are the conditions for the production of steady, useful torque fulfilled. Although the speed may differ momentarily from synchronous speed, as during the transient period of adjustment from one steady-sate operating condition to another, the average steady-state speed must be constant. The machine accommodates itself to changes in shaft torque by adjusting its torque angle. The electromagnetic torque on the rotor acts in a direction to urge the fields poles into alignment with the rsultant air-gap flux wave. For generator action, the field poles must be driven ahead of the resultant air-gap flux wave by the forward torque of a prime mover, while for motor action the field poles must be dragged behind the resultant air-

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gap flux wave by the retarding torque of a shaft load. It is as if the field poles were attached to the rotating resultant air-gap flux wave by elastic bands. The second oustanding characteristic (the adjustability of power factor) is a consequence of the fact that the resultant mmf crreating the air-gap flux is the combined effect of a-c magnetizing current in the armature and d-c excitation in the field winding. Adjustment of the field current therefore results in compensating changes in the magnetizing reactive kva in the armature. Thus an overexcited synchronous motor operates at a leading power factor. Alternatively, it may be said that an overexcited synchronous motor is a generator of lagging reactive kva. Because of the economic importance of power factor, the ability of a synchronous motor to operate a t a leading power factor is a valuable asset. The adjustability of power factor usually is the chief reason for choosing a synchronous motor instead of an induction motor. The equivalence of synchronous generators and motors as sources of reactive kva gives rise to amethod of thinking which is a value to the power-system engineer, who is faced with the problem of supplying prescribed amounts of lagging reactive kva to his system loads. He recognizes that, within certain limits, economic rather than technical factors can control the location of the excitation needed to furnish the lagging reactive kva. It may be inrtoduced in the generator fields, in the fields of synchronous motors or condensers, or by way of static capacitors connected at strategic points. With a physical picture of the internal workings in terms of rotating magnetic fields as a background, the next step in our development of synchronous-machine theory is to show that from the viewpoint of its armature circuits a synchronous machine operating under balanced polyphase conditions can be represented on a per-phase basis by a very simple equivalent circuit comprising an internal emf in series with its armature resistance and an inductive reactance. The internal emf is the excitation voltage. The reactance is the synchronous reactance. It accounts for the voltages induced in the reference phase by balanced polyphase armature currents. The synchronous reactance is derived by replacing theeffect of the rotating armature-reaction flux wave by a reactance Xφ, called the magnetizing reactance. Flux linkages with the reference phase caused by component fluxes wich are not included in the armature reaction, such as slot and coil-end leakage and spaceharmonic rotating fields, are accounted for by the armature leakage reactance Xl. The synchronous reactance is the sum of the magnetizing and leakage reactances. The unsaturated synchronous reactance can be found from the results of an opencircuit and a short-circuit test. These test methods are a variation of a testing technique applicable not only to synchronous machines but also to anything whose behavior can be approximated by a linear equivalent circuit to which Thévenin´s theorem applies. From the Thévenin-theorem viewpoint, an open circuit test gives the internal emf, and a short-circuit test gives information regarding the internal impedance. From the more specific viewpoint of electromagnetic machinery, an open-circuit test gives information regarding excitation PE-IDM.601(B)

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requirements, core losses, and (for rotating machines) friction and windage losses; a shortcircuit test gives information regarding the magnetic reactions of the load current, leakage impedances, and losses associated with the load current such as copper and stray load losses. The only real complication arises from the effects of magnetic nonlinearity, effects which can be taken into account approximately by considering the machine to be equivalent to an unsaturated one whose synchronous reactance is empirically adjusted for saturation. In terms of the equivalent circuit, the prediction of the steady-sate synchronousmachine characteristics becomes merely a study of power flow through a simple impedance with constantor easily determinable voltages at its ends. Study of the maximum-power limits for short-time overloads is merely a special case of the limitations on power flow through an inductive impedance. The power flow through such an impedance can be expressed conveniently in terms of the voltages at its sending and receiving ends and the phase angle between these voltages, when the resistance is neglected. On the basis of this equation, the internal phenomena in synchronous machines are those of power flow through the magnetizing reactance Xφ with the air-gap voltage Er at one end and the excitation voltage Eƒ at the other, the time-phase angle between these voltages being the internal torque angle between the interacting magnetic fields within the machine. The result so obtained is completely in agreement with the basic torque equation, on which our theory of torque production in rotating machines is based. When synchronous generators are operated in parallel, they must be running in synchronism. Consequently the system frequency and the division of active power among them depend on their prime-mover throttle settings and speed-power characteristics. Generator field control affects system voltage and the division of reactive kva among paralleled alternators. Unlike paralleled d-c generators, however, field control has essentially no effect on the division of the active-power load. Although we have simplified the synchronous machine considerably in this chapter, nevertheless the results which we have obtained here enable us to predict the normal steadystate characteristics with sufficient accuracy for many purposes. When more accurate results are required, the effects of magnetic saturation and of salient poles must be properly accounted for.

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CHAPTER 15 DAMAGES. NOMENCLATURE Vocabulary Adjust, to Bend, to Blow Break, to Breakage Breakdown Burst, to Chock, to Chip, to Clog, to Corrosion Crumble, to Crush, to Damage Deformation Disconnect, to Dismantle Erosion Fouling Fracture Friction Impact Knock, to Leak, to Leak Loose, to Noise Overhold Overload, to Oxidation Pounding Scouring action Split, to Spoil, to Stick, to

Ajustar Doblar Golpe Romper Rotura Avería Estallar, reventar Obturar, atascar Astillar Atascar Corrosión Desmoronarse Romper por compresión Daño Deformación Desconectar Desmontar, desarmar Erosión, desgaste Incrustaciones Fractura Rozamiento Golpe Golpear Tener fugas, gotear Fuga Aflojar, soltar Ruido Revisión Sobrecargar Oxidación Golpeo, martilleo Acción abrasiva Partir, rajar Estropear Agarrotarse, atascarse 121

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INGLÉS TÉCNICO-MARÍTIMO Stop up, to Stopped up Rub, to Vibrate, to Vibration Wear, to Wear out, to Wearing Worn

Obstruir, tapar, cegar Obstruido Rozar Vibrar Vibración, trepidación Desgastar Desgastar Desgaste, deterioro Gastado

Expressions of Damages What is the trouble with the engine?.

¿Qué avería tiene la máquina?.

The engine cannot be started.

El motor no se puede poner en marcha.

The starting pressure ir too low.

La presión de arranque es demasiado baja.

The piston of the sliding valve is stuck. enganchado.

El

The spring is broken.

El muelle está roto.

The valve must be dismantle.

La válvula debe desmontarse.

The spring must be changed.

El muelle debe cambiarse.

The engine resistance is great.

La resistencia del motor es muy grande

The bearings are bad adjusted.

Los cojinetes están mal ajustados.

There is an excessive friction.

Hay demasiado rozamiento.

The exhaust valve is not airtight.

La válvula de escape no es estanca.

The rings are worn out.

Los aros están gastados.

No combustion is produced.

No se produce combustión.

The fuel does not reach the combustion

No llega el combustible a la cámara de

chamber.

combustión.

The fuel pipe is stopped up.

La tubería de combustible está atascada.

The device is not properly set up.

El mecanismo no está bien ajustado.

The fuel pump is badly adjusted.

La bomba de combustible está mal regulada.

There is no combustion in some of the cylinders.

En algunos de los cilindros no se produce la combustión.

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The fuel contains water.

El combustible contiene agua.

There is no combustion in one cylinder.

No hay combustión en un cilindro.

There is air in the fuel pump.

La bomba de combustible tiene aire.

The fuel pump does not maintain the pressure.

La bomba de combustible no mantiene la presión.

The fuel pump has leaks.

La bomba de combustible tiene fugas.

The injector must be changed.

Debe cambiarse el inyector.

The nozzle is stopped.

La tobera está obstruida.

Functions of damage control Aboard ship, the overall damage and casualty control function is composed of two separated but related phases: the engineering casualty control phase and the damage control phase. The engineer officer is responsible for both phases. The engineering casualty control phase is concerned with the prevention, minimization, and correction of the effects of operational and battle casualties to machinery, electrical systems, and piping installations, to the end that all engineering services may be maintained in a state of maximum reliability under all conditions of operation. Engineering casualty control is handled almost entirely by personnel of the engineering department. The damage control phase, on the other hand, involves practically every person aboard ship. The damage control phase is concerned with such things as the preservation of stability and watertight integrity, the control of fires, the control of flooding, the repair of structural damage, and provide countermeasures in the event of nuclear, biological, and chemical attack. The broad objectives of damage control are to prevent, minimize, and correct the effects of operational and battle damage to the ship and to personnel in order to maintain the firepower, mobility, maneuverability, stability, and bouyancy of the ship. In other words, damage control aims at maintaining the ship and its personnel in such a condition that the ship can carry out its assigned mission. The damage control organization is the means by which the objectives of damage control can be attained. In fact, organization is the key of successful damage control. The damage control organization establishes standard procedures for handling various kinds of damage and its sets up training procedures so that every person should immediately know what to do in each emergency situation. Both the preventive and the corrective aspects of damage control are vitally important. The preventive aspects of damage control require the efforts of all deparments in establishing material conditions of readiness, in training personnel, and in maintaining the ship in the best possible condition to resist damage. To achieve this ends, the ship´s damage damage control 123

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organization must be coordinated with other elements of the ship´s organization. In each department, therefore, specific damage control duties must be assigned to individuals in each division; this includes the designation of a division damage control petty officer. The corrective (or action) aspects of damage control requires the damage control battle organization to promptly restore the offensive and defensive capabilities of the ship. As previously noted, the engineer officer is responsible for damage control. The damage control assistant (DCA), who is under the engineer officer, is responsible for establishing and maintaining an effective damage control organization. Specifically, the DCA is responsible for the prevention and correction of damage, the training of ship´s personnel in damage control, and the operation, maintenance, and care of certain machinery, drainage, and piping systems not specifically assigned to other departments or divisions. There are actually two damage control organizations: the damage control administrative organization and the damage control battle organization. The damage control administrative organization is an integral part of the engineering department organization. The damage control battle organization includes damage control central and various repair parties. The damage control battle organization varies somewhat from one ship to another, depending upon the size, type, and mission of the ship. However, the same basic principles apply to all damage control organizations. The primary purpose of damage control central is to collect and compare reports from the various repair stations in order to determine the condition of the ship and the corrective action to be taken. The damage control assistant, at his battle station in damage control central, is the nerve center and directing force of the entire damage control organization. He is assisted in damage control central by a stability officer, a casualty board operator, and a damage analyst. In addition, representatives of the various divisions of the engineering department are assigned to damage control central. In damage control central, repair party reports are carefully checked so that immediate action can be taken to isolate damage systems and to make emergency repairs in the most effective manner. Graphic records of the damage are made on various damage control diagrams and status boards, as the reports are received. For example, reports on flooding are marked up, as they come in, on a status board that indicates liquid distribution before damage. With this information, the stability and bouyancy of the ship can be estimated and the necessary corrective measures can be determined. If damage control central is destroyed or is for other reasons unable to retain control, the repair stations, in designated order, take over the functions of damage control central. Repair parties are assigned to specifically located stations. Repair stations may be further subdivided into unit patrols to permit dispersal of personnel and a wide coverage of the assigned areas. Provisions are made for passing the control of each repair station down through the officers, petty officers, and nonrated men so that no group will ever be without a leader. PE-IDM.601(B)

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The number of repair parties in the damage control organization depends upon the size, type, and mission of the ship. Maintaining watertight integrity The success of damage control depends in part upon the proper utilization of the watertight integrity features of the ship. Compartmentation is a major watertight integrity feature of a naval ship. The ship is divided into compartments to control flooding, to strengthen defense against NBC attack, to segregate activities, to provide underwater protection by means of tanks and voids, to strengthen the structure of the ship, and to provide a means of controlling buoyancy and stability. Most large combatant ships have an armor belt to protect vital machinery spaces. In some cases, where an increase in armor plating would reduce the ship´s speed or have an adverse effect on the operation of the ship (as in the case of aircraft carriers), compartmentation is increased to compensate for the reduction of armor. Every naval ship is divided by decks and bulkheads both above and below the waterline into as many watertight compartments as are compatible with the mission of the ship. In general, increasing the amount of compartmentation increases the ship´s resistance to sinking. The original watertight integrity of a naval ship is established when the ship is built. This original watertight integrity may be reduced or destroyed through enemy actions, storm damage, collision, stranding, or negligence. It is the responsability of the engineer officer to see that the ship´s watertight integrity is not impaired through negligence and that any impairment is corrected as rapidly as possible. To ensure the maintenance of watertight integrity, a thorough system of inspections and tests is prescribed. Material conditions of readiness refers to the degree of access and system closure to limit the extent of damage to the ship. Maximum closure is not maintained at all times because it would interfere with the normal operation of the ship. For damage control purposes, naval ships have three material conditions of readiness, each condition representing a different degree of tightness and protection. The three material conditions of readiness are called X-RAY, YOKE, and ZEBRA. These titles, which have no connection with the phonetic alphabet, are used in all spoken and written communications concerning material conditions. Condition X-RAY, which provides the least protection, is set when the ship is in no danger from attack, such as when it is at anchor in a well protected harbor or secured at a home base during regular working hours. Condition YOKE, which provides somewhat more protection tha condition X-RAY, is set and maintained at sea. It is also maintained in port during wartime and at other times in port outside of regular working hours. Condition ZEBRA is set before going to sea or entering port, during wartime. It is also set immediately, without further orders, when manning general quarters stations. Condition 125

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ZEBRA is also set to localize and control fire and flooding when not at general quarters stations.

DAMAGE CONTROL CENTRAL “F-100”.

Fundamentals of firefighting Fire is a constant potential hazard aboard ship. All possible measures must be taken to prevent the occurrence of fire or to bring about its rapid extinguishment. In many cases, fires occur in conjunction with other damage, as a result of enemy action, weather, or accident. Unless fire is rapidly and effectively extinguished, it may easily cause more damage than the initial casualty. In fact, fire may cause the loss of a ship even after the original damage has been repaired or minimized. Fire, also called burning or combustion, is a rapid chemical reaction that results in the release of energy in the form of light and noticeable heat. Most combustion involves very rapid OXIDATION—that is, the chemical reaction by which oxygen combines chemically with the elements of the burning substance. PE-IDM.601(B)

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Even when oxidation proceeds very slowly, as in the case of a piece of iron that is rusting, a small amount of heat is generated. However, this heat is usually dissipated before there is any noticeable rise in the temperature of the material being oxidized. With certain types of materials, slow oxidation can turn into fast oxidation (fire) if the heat is not dissipated. When this occurs, we say that SPONTANEOUS COMBUSTION has occurred. Such things as rags or papers soaked with animal or vegetable fats or with paints or solvents are particularly subject to spontaneous combustion if they are stowed in confined spaces where the heat of oxidation cannot be dissipated rapidly enough. In order to have a combustible fuel or substance take fire, it must have an ignition source and it must be hot enough to burn. The lowest temperature at which a flammable substance gives off vapors that will burn when a flame or spark is applied is called the FLASH POINT. The FIRE POINT, which is usually a few degrees higher than the flash point, is the temperature at which the fuel will continue to burn after it has been ignited. The AUTOIGNITION or SELF-IGNITION POINT is the lowest temperature to which a substance must be heated to give off vapors that will burn without the applicationof a spark or flame. In other words, the auto-ignition point is the temperature at which spontaneous combustion occurs. The auto-ignition point is usually at a much higher temperature than the fire point. The range between the smallest and the largest amounts of vapor in a given quantity of air that will burn or explode when ignited is called the FLAMMABLE RANGE or the EXPLOSIVE RANGE. Say, for example, that a substance has a flammable or explosive range of 1 to 12 percent. This means that fire or explosion can occur if the atmosphere contains more than 1 percent but less than 12 percent of the vapor of this substance. In general, the percentages referred to in connection with flammable or explosive ranges are percentages by volume. It should be apparent by now that a fire cannot exist without three things: (1) a combustiblematerial, (2) a sufficiently high temperature, and (3) a supply of oxygen. Because of these three requirements, the process of fire is sometimes regarded as being a triangle with the three sides consisting of of FUEL, HEAT, and OXYGEN. As we will see presently, the control and extinguishment of fires is generally brought about by eliminating one side of the fire triangle—that is, by removing fuel, heat, or oxygen. Fires are classified according to the nature of the combustibles (or fuels) involved. The classification of any particular fire is of great importance, since it determines the manner in whiich the fire must be put out. Fires are classified as being class A, class B, class C, or class D fires. CLASS A fires are those occurring in such ordinary combustible materials as wood, cloth, paper, upholstery, and similar materials. Class A fires are usually extinguished with water, using high or low velocity fog or solid streams. Class A fires leave embers or ashes and they must always be overhauled.

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CLASS B fires are those occurring in the vapor-air mixture over the surface of flammable liquids such as gasoline, jet fuels, diesel oil, fuel oil, paints, thinners, solvents, lubricating oils, and greases. Dry chemical, foam, light water, carbon dioxide, or water fog can be used to extiguish class B fires; the choice of agent depends upon the circunstances of the fire. CLASS C fires are those occurring in electrical equipment. Nonconducting extinguishing agents such as dry chemicals and carbon dioxide are used for extinguishing class C fires. Carbon dioxide is the preferred extinguishing agent because it leaves no residue. CLASS D fires are those occurring in combustible metals such as magnesium, titanium, and sodium. Special techniques have been developed for the control of this type of fire. In general, fires may be extinguished by removing one side of the fire triangle (fuel, heat, or oxygen) or by slowing down the rate of combustion. The method or methods of extinguishment used in any specific instance depend upon the classification of the fire and the circumstances surrounding the fire. Although it is not usually possible to actually remove the fuel in order to control a fire, there may be circumstances in which fuel removal is possible. If part of the fuel that is near or actually in a fire can safely be jettisoned over the side, this should be done as soon as possible. Damage control parties must stand ready at all times to shift combustibles to safe areas and to take whatever measures that are possible to prevent additional fuel from coming into contact with the fire. In particular, supply valves in gasoline and oil lines must be closed immediately. If enough heat can be removed by cooling the fuel to a temperature below that at which it will support combustion, the fire will go out. Heat may be transferred in three ways: by radiation, by conduction, and by convection. In the process known as radiation, heat is radiated in all directions; it is radiated heat that causes you to feel hot when you stand near an open fire. In conduction, heat is transferred through a substance or from one substance to another by direct contact from molecule to molecule; thus a thick steel bulkhead with a fire on one side conducts heat from the fire to the adjoining compartments. In convection, the heated air and other gases rising from a fire bring heat to all combustible materials within reach. Heat transfer by convection is a particular danger in the case of ventilation systems, which may carry heated gases to places that are very far removed from the original fire. To eliminate the heat side of the fire triangle, it is necessary to cool the fire by applying something that will absorb the heat. Although some other materials serve this purpose, water is the most commonly used cooling agent. Water may be applied in the form of a solid stream, as a fog, or incorporated in foam. The way in which the water or other cooling agent is applied depends upon the nature of the fire. PE-IDM.601(B)

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The third component of the fire triangle, oxygen, is difficult to control because we obviously cannot remove oxygen from the atmospheric air that normally surrounds a fire. However, oxygen can be diluted or displaced by other substances that are noncombustible, so that extinguishment of the fire will occur. If fire occurs in a closed space, it can be extinguished by diluting the air with carbon dioxide (CO²) gas. This dilution of the air must proceed to a certain point before the flames are extinguished, but no fire can exist after this point has been reached. In general, a large enough volume of CO² must be used to reduce the oxygen content to 15 percent or less. The amount of oxygen normally present in air is about 21 percent. Steam and foam are also used to keep oxygen from reaching the burning materials, thus smothering the fire. Dry chemical fire extinguishing agents extinguish fires by a process that is not quite the same as removing one side of the fire triangle. It is believed that these agents achieve their extinguishing effects by interfering with the combustion reaction. No matter what basic method of fire extinguishment is used, it must be used very rapidly if the fire is to be brought under control. Most fires start from quite small points of ignition, but they grow by leaps and bounds. If a fire is to be successfully extinguished, it must be done as rapidly as possible. Even a slight delay may cause the fire to grow beyond control with the available equipment. When a substance burns, a number of chemical reactions occur. These reactions result in the formation of flame, heat, and smoke. They also result in the production of a number of gases and other combustion products, and frequently they cause a reduction in the amount of oxygen available for breathing. All of these effects of fire are vitally important to the firefighter, who must be prepared to protect himself against them. In order to avoid injury or loss of life, it is necessary to protect against flame, heat, and smoke. Before entering a compartment or area where a fire exists, the firefighter should be in proper dress. Pant legs should be tucked into socks. The collar should be buttoned. The firefighter should wear asbestos gloves, a helmet, a head lamp, and an oxygen breathing apparatus (OBA). The flame and the heat from a fire are intense, but proper dress will help to prevent burns. The smoke will make it hard to see and hard to breathe, but the OBA and the head lamp will help the firefighter to cope with these problems. Some of the gases produced by a fire are toxic (poisonous) and others are dangerous in other ways, even though they are not toxic. Some of the gases commonly produced by a fire are discussed briefly in the following paragraphs. CARBON MONOXIDE is produced when fire occurs in a closed compartment or under other conditions where there is not enough oxygen for the complete combustion of all the carbon in the burning material. Carbon monoxide, which has the chemical formula CO, is a colorless, odorless, tasteless, and nonirritating gas. It is DEADLY even in small 129

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concentrations. A person who is exposed to a concentration of 1.28 percent CO in air will become unconscious after two or three breaths and will probably die in 1 to 3 minutes. Carbon monoxide is also very dangerous because of its very wide explosive range. If carbon monoxide is mixed with air in the amount of 12.5 to 74 percent by volume, an open flame or even a spark will set off a violent explosion. CARBON DIOXIDE (CO²) is a colorless, odorless gas that is formed by the complete combustion of the carbon in burning materials. CO² is not poisonous; its main danger to the firefighter is that an atmosphere of carbon dioxide does not provide oxygen to breathe, and asphyxiation may result. The danger of asphysiation is particularly great because carbon dioxide, being colorless and odorless, does not give any warning of its presence even when it is present in dangerous amounts. Carbon dioxide does not support combustion and it does not form explosive mixtures with any substances; because of these characteristics, it is very useful as a fire extinguishing agent. It is also used for inerting fuel oil tanks, gasoline tanks, and similar spaces. HYDROGEN SULFIDE (H2S) is a colorless gas. In low concentrations, hydrogen sulfide smells like rotten eggs. Hydrogen sulfide is generated in some fires; it also occurs as the result of the rotting of foods, cloth, leather, and other organic materials. Air that contains 4.3 to 46 percent hydrogen sulfide is violently explosive in the presence of flame. Hydrogen sulfide is extremely poisonous is breathed, even in concentrations as low as 0.01 percent. Acute poisoning results from breathing hydrogen sulfide in larger concentrations; rapid unconsciousness, cessation of breathing, and death can occur in a very few minutes from breathing an atmosphere that contains from 0.07 to 0.10 percent hydrogen sulfide. When a fire occurs in a closed compartment or similar space, an inadequate supply of oxygen for breathing may result. An enormous amount of oxygen is used by the fire itself, leaving relatively little oxygen for men to breathe. The amount of oxygen normally present in the air is 21 percent, and human beings breathe and work best with this amount of oxygen. When there is only 17 percent oxygen in the atmosphere, people breathe a little faster and deeper. When there is only 15 percent oxygen, a person is likely to become dizzy, having a buzzing in his ears, have a rapid heartbeat, and have a headache. When the oxygen content falls to 9 percent, unconsciousness may occur. Death is likely to result when the oxygen content of the atmosphere is 7 percent or less. Effects of nuclear explosions Nuclear warfare is that in which explosions are produced by the processes of nuclear fission or nuclear fusion. Nuclear explosions may be achieved with bombs or with warheads in guided missiles, torpedoes, rockets, and similar remote control weapons. Nuclear weapons cause destruction to materials by blast or shock or heat; they cause casualties to personnel by blast, heat, or nuclear radiation. Except for the nuclear radiation,

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nuclear weapons are similar to but immensely more powerful than ordinary high explosive weapons. The effects of nuclear explosions vary, depending upon the energy yield of the weapon, the manner in which the weapon is exploded, and other factors. The energy yield of a nuclear weapon is described in terms of the amount of TNT that would be required to release a similar amount of energy. Thus a nuclear weapon capable of releasing an amount of energy equivalent to the energy released by 20,000 tons of TNT is said to be a 20-kiloton weapon. A nuclear weapon capable of releasing an amount of energy equivalent to the energy released by 1,000,000 tons of TNT is said to be a 1-megaton weapon. The bombs dropped on Japan in 1945 were in the 20-kiloton range. The weapons variously referred to as hydrogen bombs, H-bombs, fusion bombs, or thermonuclear bombs are in the megaton range. The general effects of shock, blast, heat, and nuclear radiation occur in any nuclear explosion. However, the specific details of these effects vary according to the location of the explosion. In considering the effects of nuclear explosions, then, it is necessary to identify the explosions as (1) airbursts, (2) high-altitude bursts, (3) surface bursts, and (4) subsurface bursts. The information on the effects of the various types of bursts is based on observations made during the Japan explosions and during various test explosions. Airburst. Almost immediately after a nuclear explosion, the weapon residue incorporates material from the surrounding medium and forms an intensely hot and luminous mass, roughly spherical in shape, called a fireball. An airburst is defined as one in which the weapon is exploded in the air at such a height that the fireball does not touch the surface of the earth. For example, in the explosion of a 1-megaton weapon, the fireball may grow until it is nearly 7200 feet (1.3 miles) across. This means that, for a 1-megaton weapon, the explosion must occur at least 3600 feet above the earth´s surface if it is to be called an airburst. The diameter of a 20-kiloton weapon fireball is aproximately 900 feet. The interior temperature of the fireball is so high (tens of millions of degrees F, as compared with a maximum of 9000°F in a conventional high-explosive weapon) that all substances present are in the form of vapor. Substances present include radiactive fission fragments, unfissioned nuclear material, neutron induced gamma radiation, and materials that were in the vicinity of the explosion. As the tenperature falls, this vapor condenses to form a cloud. In addition, strong inflowing winds created by the rising fireball force up dust and other debris from the earth´s surface, if the burst occurs near the earth´s surface. Consequently, there is formed a high, expanding column of dust that rises to a height commensurate with the energy of the bomb. If the cloud reaches 5 to 10 miles above the earth, there is a tendency for it to cease rising and to spread out laterally, producing the characteristic cauliflower-shaped cloud. The size of the fireball varies according to the size of the nuclear weapon. 131

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INGLÉS TÉCNICO-MARÍTIMO

As mentioned previously, the sudden liberation of energy after an explosion causes a considerable increase in temperature and pressure, so that all materials present are converted into hot compressed gases or vapors. Because these gases are at high temperatures and pressures, they expand rapidily and thus initiate a pressure wave, called a blast wave. This blast wave develops a fraction of a second after the explosion and moves outward in all directions from the fireball, at an initial speed greater than the speed of sound. As the fireball expands and cools, its rate of growth slows, allowing the blast wave to break away from the fireball and continue on its own momentum. This blast wave is measured in static overpressure, which is pressure over and above atmospheric pressure. The blast wave and its accompanying strong winds are responsible for the physycal damage caused by an airburst. High-altitude burst. A high-altitude burst is defined as one in which the point of detonation is at an altitude of more than 100,000 feet. Because the air is less dense at high altitudes, the effects of a high-altitude burst are somewhat different than the effects of an airburst. In a high-altitude burst, a very large proportion of the energy is released in the form of heat. Surface burst. A surface burst is one that occurs at or slightly above the actual surface of the land or water. In a surface burst, the fireball actually touches the surface. The heat developed in a surface burst is almost the same as that developed in an airburst. The overall destruction from the blast wave is somewhat less in a surface burst than in an airburst because some of the energy is used up in vaporizing the materials on the surface and, in the case of a surface burst over land, in forming a crater. Targets close to ground zero are completely destroyed by a surface burst, but the effects of an airburst. A surface burst is likely to result in much greater fallout than an airburst. Subsurface burst. Underground burst and underwater bursts are known as subsurface bursts. When a subsurface underground burst occurs, there is of course a strong shock wave in the earth. If the detonation occurs underground but rather near the surface, the fireball may be visible as it breaks through the surface. In general, thermal radiation (heat) is absorbed by the soil and rocks and so does not represent a significanthazard in an underground burst. A radioactive cloud resulting from an uncontained underground burst contains a large amount of soil, rock, and other material: therefore, a considerable amount of radioactive fallout is to be expected from an underground burst that breaks through the surface. The effects of a subsurface underwater burst depend upon the energy yield of the weapon, the distance below the surface at which the detonation occurs, and the depth an area of the body of water. The description given here is chiefly based on observations made at the Baker test at Bikini in 1946. In this test, a 20-kiloton nuclearweapon was detonated well below the surface of a lagoon that was 200 feet deep. These conditions may be regarded as corresponding to a shallow underwater burst. In an underwater burst, a fireball is formed. However, this fireball is smaller than it is in an airburst. At the Baker test, water in the vicinity of the explosion was illuminated by the PE-IDM.601(B)

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fireball. Distortion caused by the water waves on the surface of the lagoon prevented a clear view of the fireball. The luminosity persisted for a few thousandths of a second, and disappeared as soon as the bubble of hot high pressure gases or vapors and steam constituting the fireball reached the surface of the water. At this time, the gases were expelled and cooled and the fireball was no longer visible. If the depth of burst is not too great, the bubble remains essentially intact until it rises to the surface of the water. At this point the steam and debris are expelled into the atmosphere. Part of the shock wave passes through the surface into the air and, because of high humidity, conditions are suitable for the formation of a condensation cloud known as the Wilson cloud. The underwater shock wave travels about five times as fast as the blast wave travels through air. Damage zones. Unless distorted by other factors, the blast damage following a nuclear explosion is usually confined to a circular area around ground zero, the point vertically below or above the center of a burst of a nuclear weapon. For convenience, the four general areas are designated as A,B,C, and D zones or rings. There are varying degrees of destruction within these areas. The A zone of damage is the central area immediately surrounding ground zero. This area is usually one of total destruction in which neither personnel or ordinary buildings have any chance of survival. Outside this area is the B zone, which is large belt of heavy damage. The B zone is generally about three times as large as the A zone. Injuries to personnel and structural damage would be severe but not total in the B zone. The C zone is a still larger circular belt of lesser damage surrounding the B zone. Injuries to personnel and physical damage in this area would range from moderate to light. In the outer D zone, damage would be light. Beyond the D zone, little or no damage would be sustained.

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