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CENTRIFUGA TEMPLATE CREATED BY DATE OF CREATION VERSION TITLE OF TEMPLATE

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Vikram Sharma 14th of April 2013 A Centrifugal Pump Calculation Template

1. DISCLAIMER

This template was created by Vikram Sharma with the intention for academic purpose. It may be used for pre matter expert. Point to note that this calculation template shall not be used for detail engineering calculation a used for detail engineering without the approval of principal / custodian / subject matter expert, the designer / tool. Any comments about this template, please email it to [email protected]. 2. WHAT IS A CENTRIFUGAL PUMP?

A centrifugal pump is an equipment that converts the input power to kinetic Liquid enters the pump through the eye of the impeller which is rotating at h pump casing. Due to this rotation, a vacuum is created at the impeller eye tha the velocity at the edge or tip of the vane impeller. Therefore, it can be said t be higher.

3. IMPORTANT FEATURES Require input from user Scroll down option Indicative cell for nature of flow. Contains built-in formula to provide results.

4. PUMP FUNDAMENTALS a. Suction and Discharge Vessel / Tank Dimensions LZAHH : Trip alarm when the liquid reached the maximum level height. In other word HLL : High working liquid level. LLL : Low working liquid level. b. Pump Dimensions Hs,e Hs,f Hd,f Hd Hd,e

: : : : :

Elevation height of suction vessel / tank from ground / grade. Height of pump suction flange from ground / grade. Height of pump discharge flange from ground / grade. Height of discharge pipe from ground / grade. Elevation height of discharge vessel / tank from ground / grade.

c. Fluid Important Parameter Rated Mass flow (RM) : It is defined as the mass flow rate (kg/h) multiplied by a design factor (%)

Rated Mass Flow (RM ) = Normal Mass Flowrate (M ) x Design Fact Rated Vol flow (RV) : Rated Mass Flow (RM) (kg/h) / Density (kg/m3)

Rated Vol. Flow (RV) = Rated Mass Flow (RM ) / Density (

Nominal Diameter (DN) : Outer diameter of the pipe (m) based on the requirements set by PTS 31.38.0

Inner Diameter (I.D) : It is defined as the the outer diameter of the pipe based on the DN and pipe s

Inner Diameter (I.D) = Outer Diameter (O.D) Liquid Velocity : It is calculated based on the equations provided below.

Rated Mass Flow (RM ) = Density of Liquid (

Reynolds's Number (Re) : It is a dimensionless parameter to determine the nature of flow of liquid, i.e.

Reynolds (Re) = [Density (ρ) x Liquid Velocity (VL,s or VL,d) x Inner D

Moody's friction factor (fm) : A value that is used to describe the friction factor of a pipe based on the flow

Laminar: Re = 64 / Re ; Turbulent: 1/(√f ) = Static Height of Liquid (ΔPs,st) : The pressure exerted by the liquid due to its height in the vessel / tank

Suction vessel : 0.0981 x (LLL - Hs,e - Hs,f) x ( Discharge vessel : 0.0981 x (Hd - Hd,f) x (ρ

Suction Pressure (Ps) : It is calculated based on the Minimum Operating Pressure of the suction ves

Suction Pressure (Ps) = Min. Op. Pressure (MiOP)

Discharge Pressure (Pd) : It is calculated based on the Design Pressure of the receiving vessel / tank or and equipments.

Discharge Pressure (Ps) = Design Pressure / B.L at the receiving side Differential Pressure (DP) : It is the pressure difference between discharge and suction in bar.

Differential Pressure (DP) = Discharge Pressure (bar)

Differential Head (DH) : It is basically the differential pressure converted to head based on the equatio

Differential Head (DH) = Differential Pressure (bar) x (0.0981 x (

Hydraulic Horse Power (hyd kW) : It is describe as the power provided by hydraulic system. It is directly propor

of a system.

Hydraulic Horsepower (hyd kW) = [Rated Vol. Flow (RV) x Diff. Hea

Brake Horsepower (bk kW) : Also known as shaft horsepower. It is defined as the real horsepower going t

Break Horsepower (bk kW) = hydraulic Horsepower (hyd kW) / Effic Temp. rise due to pumping (Tr) : It is a measure of temperature rise due to pumping and it is calculated based

Temp. rise (Tr) = [ Differential Head (DH) / ( Specific Heat Capacity (

In this equation, the efficiency is expressed in decimal. Therefore, an efficie kCal/kgºC. Pump Shut Off Head (Pso) : Pump shut off head is described as the pumping of liquid "upwards" until it up any more further. It is calculated using the equation provided below.

Pump Shut Off 1(Pso,1) = [ 1.25 x (Pd - Ps) ] + DP of Suct. Vessel / T Pump Shut Off 2 (Pso,2) = [ 1.25 x (Pd - Ps) ] + [ 0.0981 x (HLL + Hs,e 5. REFERENCES 5a. Website(s) http://www.cheresources.com/invision/topic/9646-centrifugal-pumps/ http://www.slideshare.net/mahuda72/centrifugal-pump-sizing-selection-and-design-practices-4425151 5b. E-book(s) Section 12 - Pumps & Hydraulic Turbines, Engineering Data Book 12th Ed. SI Vol. I and II Section 17 - Fluid Flow and Piping, Engineering Data Book 12th Ed. SI Vol. I and II

5c. Standard(s) Petronas Technical Standards - Design and Engineering Practice Manual - Piping - General Requirements PTS 31.38.01.

CENTRIFUGAL PUMP GUIDE

tion for academic purpose. It may be used for preliminary design engineering calculation with the approval for principal / custodian / subject all not be used for detail engineering calculation and designer / user shall use the program that is provided by contractor. If this tool is to be l / custodian / subject matter expert, the designer / user shall bear full responsibility of the accuracy and validity of the results obtained from this [email protected].

quipment that converts the input power to kinetic energy. The energy conversion is done by accelerating the liquid by a rotating item called impeller. ough the eye of the impeller which is rotating at high speed. The rotation of the impeller accelerates radially outward the liquid from the otation, a vacuum is created at the impeller eye that consistenly draws in more liquid into the pump. The energy transferred to the liquid relates to ip of the vane impeller. Therefore, it can be said that the faster the impeller revolution or bigger the impeller size, the velocity of the liquid will

reached the maximum level height. In other words, high level trip.

vessel / tank from ground / grade. nge from ground / grade. flange from ground / grade.

ge vessel / tank from ground / grade.

ow rate (kg/h) multiplied by a design factor (%)

) = Normal Mass Flowrate (M ) x Design Factor (%)

g/h) / Density (kg/m3)

Rated Mass Flow (RM ) / Density (ρ)

(m) based on the requirements set by PTS 31.38.01.11.

r diameter of the pipe based on the DN and pipe size charts and the corresponding thickness

Diameter (O.D) - 2 x Thickness (t)

e equations provided below.

= Density of Liquid (ρ) x Cross Sectional Area based on I.D of suction or discharge x Velocity (VL,s or VL,d)

eter to determine the nature of flow of liquid, i.e. laminar, transition or turbulent.

) x Liquid Velocity (VL,s or VL,d) x Inner Diameter (I.D) ] / Viscosity (µ)

cribe the friction factor of a pipe based on the flow, i.e. laminar or turbulent.

√f ) = -2 log10 [ (ɛ/3.7D) + (2.51/Re√f) ]

liquid due to its height in the vessel / tank

Hs,f) x (ρ/1000) Hd,f) x (ρ/1000)

e Minimum Operating Pressure of the suction vessel minus the pressure drop at the suction due to friction, items and equipments

= Min. Op. Pressure (MiOP) - Σ (ΔPs,f + ΔPs,e + ΔPs,i)

e Design Pressure of the receiving vessel / tank or battery limit at the receiving side, and the pressure drop at the discharge side due to friction, items

s) = Design Pressure / B.L at the receiving side + Σ (ΔPd,f+ ΔPd,e + ΔPd,i)

e between discharge and suction in bar.

DP) = Discharge Pressure (bar) - Suction Pressure (bar)

al pressure converted to head based on the equation provided below.

) = Differential Pressure (bar) x (0.0981 x (ρ/1000))

provided by hydraulic system. It is directly proportional to flow rate and pressure. Besides this, it is inversely proportional to the efficiency

(hyd kW) = [Rated Vol. Flow (RV) x Diff. Head (DH) x Gravity Acceleration (g) x Liquid Density (ρ)] / 3,600,000

power. It is defined as the real horsepower going to the pump. It shall not be equated to the horsepower used by the motor.

kW) = hydraulic Horsepower (hyd kW) / Efficiency (%)

ure rise due to pumping and it is calculated based on the equation provided below.

erential Head (DH) / ( Specific Heat Capacity (Cp) x 427) ] x [ (1/e) -1 ]

ncy is expressed in decimal. Therefore, an efficiency of 78.0% is represented as 0.780. Also, the specific heat capacity is expressed in

ribed as the pumping of liquid "upwards" until it reached a certain height and from this point, the pump is unable to push the liquid alculated using the equation provided below.

Ps) ] + DP of Suct. Vessel / Tank + Max Suction Pressure at HLL Ps) ] + [ 0.0981 x (HLL + Hs,e - Hs,f) x SG ]

-and-design-practices-4425151

h Ed. SI Vol. I and II

al - Piping - General Requirements PTS 31.38.01.11 November 2009.

for principal / custodian / subject by contractor. If this tool is to be idity of the results obtained from this

e liquid by a rotating item called impeller. y outward the liquid from the ergy transferred to the liquid relates to er size, the velocity of the liquid will

items and equipments

at the discharge side due to friction, items

ely proportional to the efficiency

eat capacity is expressed in

unable to push the liquid

CENTRIFUGAL PROJECT: LOCATION: CLIENT: CONTRACTOR:

AUTHOR: VERIFIED: APPROVED:

1. GENERAL INFORMATION Name of Liquid: Pump. Temp (T,p): Density @ 15ºC (ρ): Visc. (µ):

LZAHH

ºC kg/m3 Pa.s

Vap. Pressure (Pv): Mass Flow (M): Design Factor:

m

HLL

m

LLL

m

m

Hs,e =

Hs,f =

m

LZAHH HLL Hd =

m

LLL

Hd,f =

SUMMARY SUCTION PRESSURE (Ps): DISCHARGE PRESSURE (Pd): NPSH(A): DIFF. PRESSURE (DP): DIFFERENTIAL HEAD (DH): HYDRAULIC POWER, hyd kW: BRAKE HORSEPOWER, bk W: TEMP. RISE (Tr):

m

bar bar m bar m kW kW ºC

Hd,e =

CENTRIFUGAL PUMP CALCULATION TEMPLATE DATE: DATE: DATE:

Visc. (ν): Vap. Pressure (Pv): Mass Flow (M): Design Factor:

REV:

m2/s bara kg/h

Rated Mass Flow (RM): Specific Gravity (SG): Rated Vol. Flow (RV):

3. SUCTION VESSEL INFORMATION MiOP of Vessel/Tank: MOP of Vessel/Tank: DP of Vessel/Tank:

bara bara bara

4. PIPE SUCTION INFORMATION DN: Sch. No.: OD: Thickness: Suct. Length (L): Design Factor: Abs. roughness (ɛ): Σ Suct. Length (L):

Moody's Fric. Factor (Fm): Suct. Fric. ΔP (ΔPs,f): Suct. items ΔP (ΔPs,i): Suct. equip. ΔP (ΔPs,e): Static H. of Liq. (ΔPs,st): SUCT. PRESSURE (Ps):

5. DISCHARGE VESSEL INFORMATION MiOP of Vessel/Tank: MOP of Vessel/Tank: DP of Vessel/Tank: BL Land. Pres. (P):

bara bara bara bar

m m m

6. PIPE DISCHARGE INFORMATION DN: Sch. No.: OD: Thickness: Disch. Length (L): Design Factor:

Liquid Velocity (VL,d): m

Moody's Fric. Factor (Fm): Disch. Friction ΔP (ΔPd,f):

m

Abs. roughness (ɛ): Σ Discharge Length (L):

Disch. items ΔP (ΔPd,i): Disch. equip. ΔP (ΔPd,e): Static H. of Liq. (ΔPd,st):

m

DISCHARGE PRESSURE (Pd): 7. NPSH, DIFFERENTIAL PRESSURE AND HEAD Vap. Pressure / Head: Static H. of Liq. / Head: Σ Suct Pressure Drop ΣΔPs / Head:

8. DIFFERENTIAL PRESSURE AND HEAD DIFFERENTIAL PRESSURE (DP): DIFFERENTIAL HEAD (DH): 9. PUMP SHUT-OFF HEAD Diff. Pres. (DH): DP of Suct. Vessel/Tank: Static H. of Liq. (ΔPs,st): Coefficient for Pso: 10. PUMP EFFICIENCY Selected Eff. (Es): Est. Eff (Ee):

bar bar bar

SHUT-OFF PRESSURE 1: SHUT-OFF PRESSURE 2:

% %

11. POWER CALCULATIONS HYDRAULIC POWER, hyd kW: BRAKE HORSEPOWER, bk W: 12. TEMPERATURE RISE CALCULATION Specific Heat (Cp):

kJ/kgºC

TYPE OF ITEMS

kg/h bar m3/h

LZAHH / grade: HLL / grade: LLL / grade:

VALVE (FULLY OPEN)

m m m FITTINGS

Nature of flow: ID: Liq. vel. (VL,s): Reynolds no. (Re): Moody's Fric. Factor (Fm): Suct. Fric. ΔP (ΔPs,f): Suct. items ΔP (ΔPs,i): Suct. equip. ΔP (ΔPs,e): Static H. of Liq. (ΔPs,st): SUCT. PRESSURE (Ps):

LZAHH / grade: HLL / grade: LLL / grade:

m m/s MISCL. bar bar bar bar

TOTAL PRESSU

bar

m m m

COLEBROOK EQU Nature of flow: ID: Liquid Velocity (VL,d): Reynold (Re): Moody's Fric. Factor (Fm): Disch. Friction ΔP (ΔPd,f):

m m/s

bar

To simply this equation, let's mak shall look like:

Disch. items ΔP (ΔPd,i): Disch. equip. ΔP (ΔPd,e): Static H. of Liq. (ΔPd,st):

bar bar bar

DISCHARGE PRESSURE (Pd):

bar

MiOP / Head: Vap. Pressure / Head: Static H. of Liq. / Head: Σ Suct Pressure Drop ΣΔPs / Head:

m m m m

NPSH(A):

m

DIFFERENTIAL PRESSURE (DP): DIFFERENTIAL HEAD (DH):

bar m

SHUT-OFF PRESSURE 1: SHUT-OFF PRESSURE 2: SHUT-OFF HEAD 1: SHUT-OFF HEAD 2:

bar bar m m

Chosen Eff (Ec):

HYDRAULIC POWER, hyd kW: BRAKE HORSEPOWER, bk W:

Specific Heat (Cp): Chosen Eff (Ec): Diff. Head (DH): TEMP. RISE (Tr):

%

kW kW

kCal/kgºC m ºC

Error % (LHS and RHS Moody's Fric. Fac (Fm

Specific Gravity (SG):

TYPE OF ITEMS

DESCRIPTION

Reduced bore DN40 and smaller BALL VALVE Reduced bore DN50 and smaller Standard bore GATE VALVE Reduced bore DN40 and smaller Straight pattern Y pattern GLOBE VALVE Angle pattern Swing pattern CHECK VALVE Ball or piston type, DN40 and smaller PLUG VALVE Regular pattern BUTTERFLY VALVE DN150 and larger Flow straight through TEE-EQUAL Flow throughside outlet 90deg, R = 1.5D ELBOW 45deg, R = 1.5D 90deg, R = 4D 90deg, R = 5D BEND 180deg, R = 4D 180deg, R = 5D STRAINER Pump suction Y-type and bucket type Product outlet nozzel vessel / tank NOZZLE Product inlet nozzle vessel / tank TOTAL PRESSURE DROP OF ITEMS (ΔPs/d,i)

TYPE OF ITEMS

DESCRIPTION

No.

SUCTION SIDE C 65 45 13 65 340 160 145 135 340 45 20 20 65 20 16 14 16 25 28 250 32 64

SUCTION SIDE No. ΔP/item

TOTAL PRESSURE DROP OF EQUIPMENTS (ΔPs/d,e)

COLEBROOK EQUATION SOLVER FOR TURBULENT FLOW

To simply this equation, let's make 1/sqrt(f) = A. Therefore, the above equation shall look like:

 e  2.51 A   A  2 log 10     3.7 D  Re    e   2.51 A  A  2 log 10   2 log 10   3 .7 D   Re 

EQUATION SOL

Reynolds's number is represented by th

 e  2.51 A   A  2 log 10     3.7 D  Re    e   2.51 A  A  2 log 10   2 log 10   3 .7 D   Re   2.51 A   e  A  2 log 10   2 log 10   Re   3 .7 D 

SUCTION Abs. roughness (ɛ): ID: RHS: A: Reynold's no. (Re): LHS: Is LHS = RHS?: Error % (LHS and RHS): Moody's Fric. Fac (Fm):

DISCHARGE m

Moody's Fric. Fac. (Fm):

Specific Gravity (SG): DN: SUCTION SIDE Le (m)

m

ΔP (bar)

SUCTION SIDE ΔP (bar)

No.

DISCHARGE SIDE C Le (m) 65 45 13 65 340 160 145 135 340 45 20 20 65 20 16 14 16 25 28 250 32 64

ΔP (bar)

DISCHARGE SIDE No. ΔP/item ΔP (bar)

EQUATION SOLVER FOR LAMINAR FLOW

64 fm  Re Reynolds's number is represented by the equation presented below.

  vl  ID Re  

PIPE DN 15 20 25 40 50 80 100 150

  vl  ID Re  

SUCTION Density (ρ): Liq. vel. (VL): ID: Visc. (µ): Reynold's no. (Re): Moody's Fric. Fac. (Fm):

DISCHARGE SIDE kg/m3 m/s m Pa.s

200 250 300 350 400 500 600 750 900 1050 1200 1400 1600 1800 2000

CENT ISSUES

CENTRIFUGAL PUMP DESCRIPTION(S)