• Author / Uploaded
• Gary J. Davis, P. E.

• Categories
• Cuerda
• Cable
• Naturaleza
• Ingeniería
• Ciencia

Citation preview

WIRE ROPE USERS MANUAL

COMMITTEE OF WIRE ROPE PRODUCERS American Iron and Steel Institute

,-

\....;:::

$2.50

J

This publication is a joint effort of the . COMMITTEE OF WIRE ROPE PRODUCERS/ American Iron and Steel Institute and the WIRE ROPE TECHNICAL BOARD The Wire Rope Technical Board (WRTB) is an association of engineers representing companies that account for more than 90 percent of wire rope produced in the United States; it has the following objectives: • To promote development of engineering and scientific knowledge relating to wire rope; • To assist in establishing technological standards for military, governmental and industrial use; • To promote development, acceptance and implementation of safety standards; • To help extend the uses of wire rope by disseminating technical and engineering information to equipment manufacturers; and • To conduct and/,or underwrite research for the benefit of both industry and user. Data, specifications, architectural/engineering information and drawings presentep in this publication have been delineated in accordance with recognized professional principles and practices, and are for general information only. Suggested procedures and products should not, therefore, be used without first securing competent advice with respect to their suitability for any given application. The publication of the material contained herein is not intended' as a warranty on the part of American Iron and Steel Institute-or that of any person named herein-that these data are suitable for any general or particular use, or of freedom from infringement of any patent or patents. Any use of these data or suggested practices can only be made with the understanding that American Iron and Steel Institute makes no warranty of any kind respecting such use and the user assumes all liability arising therefrom.

COMMITTEE OF WIRE ROPE PRODUCERS American Iron and Steel Institute 1000 16th Sfreet,N. W. Wasl1!ngt9n, D.C. 20036 Copyright © 1979 by American Iron'and Steel Institute All rights reserved Printed in U.S.A. Permission to reproduce or quote any portion of this book as editorial reference is hereby granted. When making such reproductions or quotations, the courtesy of crediting this publication and American Iron and Steel Institute will be appreciated.

""

CONTENTS 1.

2. 3. 4.

5.

. 6.

APPENDIX A APPENDIXB APPENDIX C APPENDIXD APPENDIXE APPENDIX F

INTRODUCTION / 5 BASIC COMPONENTS / 7 WIRE ROPE IDENTIFICATION AND CONSTRUCTION / 9 HA'NDLINGWIREROPE /17 Receiving, Inspection and Storage /17 Wire Rope Installation / 18 Unreeling & Uncoiling / 19 Seizing Wire Rope / 22 Cutting Wire Rope / 24 End Attachments / 25 Efficiency ofEnd Attachments /25 Socketing/ 28 Wire Rope Clips / 29 How to Apply Clips / 29 Wedge Sockets / 33 Drums-Grooved / 34 Drums-Plain (Smooth) / 35 Drums-Multiple Layers / 36 OPERAnON AND MAINTENANCE OF WIRE ROPE / 37 Sheaves & Drums / 37 Bending Rope Over Sheaves & Drums / 39 Inspection of Sheaves and Drums / 42 The "X-Chart"-Abrasion Resistance vs. Bending-Fatigue Resistance / 44 Breaking in aNew Wire Rope /·45 Wire Rope and Operations Inspection / 45 Strength Loss of Rope Over Sheaves or Stationary Pins / 47 Fleet Angle / 48 Factors Affecting the Selection of Wire Rope / 49 Guideline to Inspections and Reports / 52 Field Lubrication / 68 Wire Rope Efficiency Over Sheaves. /70· PHYSICAL PROPERTIES /73. Elastic Properties of Wire Rope / 73 Design Factors / 76 Breaking Strengths / 77 _ O"rdering Storing and Unreeling Wire Rope / 97 A Glossary of Wire Rope Terms /99 Wire Rope Fittings / 109 Socketing / 120 . Shipping Reel Capacity / 125 Weights of Materials / 126 CONTENTS IN ALPHABETICAL ORDER /128 3

·r.

Acknowledgements Tabular data and accompanying reference drawings for wire rope clips were provided by The Crosby Group. All other illustrations used throughout were .furnished by member companies of the Committee of Wire Rope Producers (AISI). Drawings were prepared especially for this publication and are based wholly or in part on graphic material that originally appeared in literature issued separately by various member companies of the Committee. Numericaland factual data, not otherwise credited, were obtained from published and unpublished sources supplied by the Committee (AIS!) and by the Wire Rope Technical Board (WRTB).

". ' ...

4

~_.,

1 Introduction ma-chine: an assemblage of parts . .. that transmit forces, motion, and energy one to another in some predetermined manner and to some desired end . .. -Webster's Third New International Dictionary

In and of itself, wire rope is a machine. The geometry--{)r configuration--{)f its cross-section and the method and material of its manufacture are precisely designed to perform "in some predetermined manner and to some desired end." Hence, as befits any useful machine, it is imperative that the rope's potential use be fully recognized, that its functional characteristics be understood, and that procedures for proper maintenance be scrupulously adhered to. By giving active recognition to these generally accepted concerns, the user can be reasonably certain that maximum service life and safety will be realized for every rope installation or application. Full recognition of the inherent use-potential for wire rope derives from a realization of the great number and wide variety of ropes available for general and special operating needs. Every particular style in all sizes, constructions, grades, and cores is designed to meet some special set of functional requirements. Fabricated to close tolerances, wire rope is inspected at all significant manufacturing intervals to assure the user of a uniformly high quality product. Athoroughunderstandingof wire rope characteristics is, of course,a primary essential. This involves intimate familiarity witlioperating conditions, load factors, rope grades, and constructions. Immediately after manufacture, wire rope care becomes an overriding, necessity. At no point can aproper regard forcare and maintenance be neglected; it must be exercised in handling, shipping, storage, and in installation. Then, after the rope is put into operation, approved maintenance practices and rigorous inspection (qf both the rope and its associated equipment) must be carried out on a continuous basis. Only by strict adherence to these procedures can the rope operate with safety and effiCiency throughout its entire life span. Prepared for the long-time user as well as those unfamiliar with the product or its technology, this publication represents a joint effort by the wire rope industry. Those who already have a working knowledge of wire ropes will find in these pages a comprehensive and convenient source of reference data on such areas as properties and characteristics, handling, storage, operation and maintenance-in short, a handy checklist. As for the not-too-well informed or new user, this publication can serve as a broad-ranging introduction. For these readers, the information provided can help establish sound practices; practices of selection and application that are at once safe, efficient and economic. As a cooperative industry effort, this manual brings together a significant portion of the enormous collection of data now scattered about in the files and publications of many individual companies. The text offers many recommendations, both explicit and implied. but these have been made solely for the purpose of providing some initial judgment point from which ultimate decisions as to design and use may be made. The reader is urged to consult with the wire rope manufacturer as to the specific application planned. The manufacturer's experience can then help the user make the most appropriate 5

Ii.

choice.' In the filial analysis, responsibility for design and use decisions rest with the user. . The selection of equipment or components is frequently influenced by the special demands of an industry. An equipment manufacturer may, for reasons of space, econom.y, etc., feeic0111pelled to depart from suggested procedures given in these pages. It is important to remember that such variations from recommended practices should be regarded as potential dangers. However, when such circumstances are unavoidable they demand compensating efforts on the part of the user. These "extras" should include (but not necessarily be limited to) more frequent and more thorough inspections by skilled, specifically trained personnel. Additionally, these circumstances may demand the keeping of special lubrication and mainteriaricerecords, and the issuance of special warnings regarding removal and replacement criteria.

\.

2 Basic Components

(STRAND

!;.;,.

Figure 1. The three basic components of a typical wire rope.

Wire rope consists of three essential components. These, while fewin number', vary in both complexity and configuration so as to produce ropes for specific purposes or char~cteristics.Basically, these three components of a standard wire rope design are: 1) wires that form the strand, 2) a core, and 3) the multi-wire strands laid helically around the core (Fig. 1). Wire, for rope, is made in several materials and types; these include steel, iron, stainless steel, monel, and bronze. By far, the most widely used material is high-carbon steel. This is available in a variety of grades each of which has properties related to the basic curve for steel rope wire. (Wire rope manufacturers select the wire type that is most appropriate for requirements of the finished product.) "iron"type wire is actuaEy :i j,jh'-carbon steel and has fairly limited use except for older elevator installations. However, when iron is used for other than elevator application, it is most frequently galvanized. Steel wire strengths are appropriate to the particular grade of the wire rope in which they are used. These grades of wire rope are traction steel, mild plow steel, plow steel, improved plow steel, and extra improved plow steel. (While steel grade names originated at the earliest stages of wire rope devt"lorment, they ~";1Ve been retained and serve as indicators of the strength of a particular size and grade of rope). The strength of plow steel forms the basis for calculating the strength of all steel rope wires, and the tensile strength of any grade is not constant, but varies with the diameter-being highest for the smallest wires. The most common finish for steel wire is "bright" or uncoated. Steel wires may also be galvanized (zinc coated). "Drawn galvanized" wire has the same strength as bright wire, but wire "galvanized at finished size" is usually 10% lower in strength. In some special applications, tinned wire is used. but it should be noted that tin provides no sacrificial (cathodic) protection for the steel as does zinc. Listed in order of frequency of use, stainless steel ropes are made of AISI Types 302/304, 316, and 305. Contrary to general belief, hard-drawn stainless Type 302/304 is magnetic. Type 316 is less magnetic and Type 305 has a permeability low enough to qualify as non-magnetic. Monel Metal wire is usually Type 400 and conforms to Federal Specification QQ-N-281. Bronze wire is usually Type A Phosphor Bronze (CDA#510) although other bronzes are sometimes specified. The core is the intrinsic foundation of wire rope; and is made of materials that will provide proper support for the strands under normal bending and loading conditions. Core materials include fibers (hard vegetable or synthetic) or steel. The steel core consists either of stranded wires or of another independent wire rope. The three most commonly used core designations are: fiber core (FC), independent wire rope core (lWRC). and strand core (WSC) (Fig. 2). Catalog descriptions of the various available ropes include these abbreviations to identify the type of core. Strands are made up of two or more wires, laid in one of many specific geometric arrangements. or in a combination of steel wires with some other materials such as natural or synthetic fibers. Although it is conceivable that a 7

strand can be made up of any number of wires, or that a rope can have any number of strands, in the United States the majority of wire ropes are designed with six strands. Major U.S. strand classifications are 7-, 19-,37-,61-,91-, and 127-wire. Despite their numerical characteriiations, it should be noted that the classifications do not necessarily refer "to the actual wire count in each strand. In standard manufacturing practice, rope constructions do not necessarily have the specific wire counts given by their respective classifications. The following section, WIRE ROPE IDENTIFICATION," provides a complete description of the construction of each classification. To summarize: a wire rope consists, in most cases, of three components: wires, strands, and a core (Fig. 2). To these may be added what may be considered a fourth component: the wire rope's lubricant-a factor vital to the satisfactory performance of most operating ropes.

FIBER (FC)

INDEPENDENT WIRE ROPE CORE (IWRC)

WIRE STRAND (WSC)

Figure 2. The three basic wire rope cores. In selecting the most appropriate core for a given application, a qualified manufacturer should be called upon for guidance, Fiber cores, for example, are not recommended for applications involving elevated temperatures or high peak loads. ,

8

3 Wire Rope Identification and Construction Wire rope is identified not only by its component parts, but also by it~ construction, Le., by the way the wires have been laid to form strands, and by the way the strands have been laid around the core. In Figure 3, drawings "a" and "c" show strands as normally laid into the rope to the right-in a fashion similar to the threading in a right-hand bolt. Conversely, the "left lay" rope strands (drawings "b" and "d") are laid in the opposite direction. Again in Figure 3, the first two drawings ("a" and "b") show regular lay ropes. Following these are the types known as lang lay ropes. Note that the wires in regular lay ropes appear to line up with the axis of the rope; in lang lay rope the wires form an angle with the axis of the rope. This difference in appearance is a result of variations in manufacturing techniques: regular lay rope's are made so that the direction of thewire lay in the strand is opposite to the direction of the strand lay in the rope; lang lay ropes ("c" and "d") are made with both strand lay and rope lay in the same direction. Finally, the type "e" called alternate lay consists of alternating regular and lang lay strands.

a

b

,

d

,Fi!!llre 3.

A comparison of typical wire rope Jays: a) right rl'gular ray, b) Il'ft rl'glliar ray,

c) right lang lay, d) Il'ftlang lay, e) right altanCltl' lay.

9

. Of all wire rope types in current use, right regular lay is found in the widest range of applications. Many applications related to excavation, construction or mining, require lang lay rope. Currently, left lay rope is used less frequently. In any case, where left lay and/or lang lay are required, the manufacturer/supplier must be so informed before ordering. As for alternate lay ropes, these are used for special applications. Circumstances that favor the use of lang lay ropes derive from two unique advantages over regular lay ropes. Lang lay ropes: 1) are more resistant to bending fatigue, and 2) have a greater wearing surface per wire across the crown of the strand. The total wearing surface area of the rope is, for practical purposes, the same for both regular and lang lay ropes-with the same geometric construction and depth of wear-the eventual wear on the equipment and the service life of the rope favors laI1glay construction on applications where fatigue or abrasion are controlling factors. To illustrate this point, Figure 4 compares a regular lay with a lang lay rope, each of which has been worn to the same amount of reduction in their respective diameters. Hence, it is not the total of the rope's worn surface area that governs the life span of rope and equipment. It is, rather, the inherent characteristics of properly used lang lay ropes that gives them a significant advantage in resistance to both abrasion and fatigue. However, lang lay ropes have some disadvantages. They are more susceptible to damage resulting from: handling abuses, bending' over extremely small sheaves, pinching in undersize sheave grooves, crushing when improperly wound on drums, and they are subject to excessive rotation. In fact, this latter tendency for the rope and the strands to unwind in the same direction, requires that lang lay ropes should be secured at both ends to prevent unlaying or spinning out. Preforming is a wire rope manufacturing process wherein the strands and their wires are shaped-during fabrication-to the spiral form that they will ultimately assume in the finished rope or strand. As previously noted,wire rope strands are made up of a number of wires. I

I I

I A-· REGULAR LAY

Figure 4.

_-BI

:\1

A comparison of wear characteristics hetween l(//IR lay and r{'Rular lay rdpes. The line a-b indicates the rope axis.

10

The wire' arrangeme'nt in the strands will determine the rope's functional characteristics, i.e., its capacity to Dleet the operatjng conditions to which it wilI be subjected. There are many basic'design constructions around which standard wire ropes are built; some of these are shown in Figure 5. Four typical strand cross-sections, designed around the Warrington, Seale and Filler Wire basic constructions are shown in Figure 6. Wire ropes are identified by a nomenclature that is referenced to: 1) the number of strands in the rope, 2) the number (nominal or exact) and arrangement of wires in each strand, and 3) a descriptive word or letter indicating the type of construction. i.e., geometric arrangement of wires (Fig. 7). Under the earlier section BASIC COMPONENTS, mention was made concerning the manner in which wire rope constructions are grouped or classified. The most widely used classifications are listed and described in Table 1. At this point, it may be useful to discuss wire rope nomenclature in somewhat greater detail. It is a subject that may easily generate some misunderstanding. The reason for this stems from the practice of referring to rope either by class or by its specific construction. Ropes are classified both by the number of strands and the nurriber of wires in each strand, e.g., 6x7, 6x 19, 6x3 7,8x J 9, J 9x7, etc. However, these are'nominal classifications that mayor may not represent the actual construction: For example, the 6x19 class commonly includes constructions such as 6x21 filler wire, 6,,25 filler wire,and 6x26 Warrington Seale. Despite the fact that none of these have, 19 wires, they are designated as being in the 6x 19 classification. Hence, a supplier receiving an order for 6x 19 rope may assume this to be a class reference and is legally justified in furnishing any construction within this category. But, if the job should require the special characteristics of 6x25 W, and a 6x19 Seale (Fig. 5) is supplied in its stead, a shorter service life can be expected. To avoid such misunderstanding, the safest procedure is to order a specific construction if such geometry is essential for the intended purpose, or to order , both by class and construction, e.g., 6x 19 (6x26 Warrington Seale). Identifying wire rope in class groups facilitates selection on the basis of strength, weight/ft. and price since aU ropes within a class have the same nominal strength, weight/ft and price. As for other functional ,characteristics, these can be obtained by referencing the specific construction within the class. Only three wire ropes in the 6x 19 classification actually have 19 wires: 6x19 2 operation, 6x19 Seale, and6x19 Warrington. All the rest have different counts. There is a greater proportion of 37-wire constructions in the 6x37 class but these are infrequently produced. The more commonly available 6x37 'constructions include: 6x31 Seale. 6x31 Warrington Seale (WS). 6x36 WS, 6x4l Seale FiUerWire (SFW), 6x41. WS, 6x43 FW, '6x46 WS, etc,-none of which contains 37 wires. While a strand's interior has some significance. its important characteristics relate to the number and, in consequence, the size of the outer wires. This is discussed in somewhat greater detail in the section titled FACTORS AFFECTING THE SELECTION OFWIRE ROPE (p. 49).

11

Wire rope nomenclature also defines: length, size (Le., diam.), type, direction of lay, grade of rope, type of core. and whether it is preformed (p/f) or non-preformed (np/f). If the direction and type of lay are omitted from the rope description, it is presumed to be. a right regular lay. In addition, if no mention is made as to preforming, this will be presumed as a requirement .for preforming. On the other hand, an order for elevator rope requires an explicit statement since p/f and np/f ropes are used extensively. An example of a complete description would appear thus: 600 ft %" 6x25 FW Left lang lay Improved plow IWRC (Rope described above would be made PREFORMED.)

.....,. . ....•....\'..•....... ......,. .. ~

••••:.~ ';i.••::'

.•........ ,..,....: ,..

........• •·t,:·:·,,;>',:,• " ,.'..•...'

•,

ft•••

~

~

6125 FW

Figure 5.

Basic constructions around which standard wire ropes are built.

.. .. •..... ·!.·.···.!e.s·.. ·,\\t.·•••

••• .~!!. ·:i\· ~ e.e:::•••• • •••• e:eo:" :;...:..: :• •~. ·.!t::• ·:te· .;:·x·:;:

.....r.\.·•• •. ..... ...··E···......... ..... •.. .4...~.

~

• • •~ •

...

:- ,:0;'

!:.~:. •• :~

:.'i ••

•··..:·.·.e:!ll

--te-

6.21 SEALE WITH WITH IWRC

Figure 6.

6.31 WARRINGTON SEALE WITH IWRC

A fewcqmbinations of basic design constructions.

SEALE STRAND 19 WIRE SEALE 1·9· 9

12

:

• -::J.:;. •

~.

•••

~

Figure 7. A single wire rope strand. Wire rope is identified by reference to its number of strands, as well as the number and geometric arrangement of wires in the strand.

, \..

.

-" j

TABLE I' WIRE ROPE CLASSIFICATIONS Based on the Nominal Number of Wires in Each Strand '.-'

Description

Classification 6x7

Containing 6 strands that are made up of 3 through 14 wires, of which no more than 9 are outside wires.

. 6x19

Containing 6 strands that are made up of 15 through 26 wires, of which no more than 12 are outside wires.

6x37

Containing 6 strands that are made up of 27 through 49 wires, of which no more than 18 are outside wires.

6x61

Containing 6 strands that are made up of 50 through 74 wires, of which no more than 24 are outsid~ wires,

6x91

Containing 6 strands that are made up of 75 throughl 09 wires, of which no more than 30 are outside wires.

6x127

Containing 6 strands that are made up of 110 or more wires, of which no more than 36 are outside wires.

8x19

Containing 8 strands that are made up of 15 through 26 wires, of which no more than 12 are outside wires.

.

19x7 and 18x7

. ....

Containing 19 strands, each strand is made up of 7 wires. It is :!llanufactured by covering an inner rope of 7x7 left lang lay construction with 12 strands in right regular lay. (The rotation-resistant property that characterizes this highly specialized construction is a result of the counter torques developed by the two layers.) When the steel wire core strand is replaced by a fiber core, the decription becomes 18x7.

When acenter wire is replaced by a strand, it is considered as a single wire, and the rope classification remains unchanged. There are, of course, many' other types of wire rope, but they are useful only in a limited number of applications and, as such, are sold as specialties. Usually designated according to their actual construction, some of these special constructions are listed in Table 2 and shown in Figure 8.

/

\.~:'

13

6142 TILLER ROPE

5119 MARLINE CLAD

Figure 8. Three special purpose constructions that suggest wire rope's inherent design potential.

TABLE 2

SPECIAL CONSTRUCTIONS

3x7 Guard Rail 3x19 Slusher 6x12 Running Rope 6x24 Hawsers 6x30 Hawsers 6x42 (6x6x7) TiIle.r Rope 6x3x19 Spring Lay 5x19 Marline Clad 6x19 Marline Clad Table 2 is a much abbreviated listing of ropes designed for highly speciaiized applications. Within the scope of this publication, it is not feasible to list the many uses, nor to describe the possible design variations. Cross-sections of wire rope shown in Figures 9 and 10 are among the most commonly used, and they are arranged in their respective classification groups. Because they are in greater demand, they are more generally available. There is, however, one specialized wire rope category that requires some discussion here-elevator rope. In this application, selecting the right rope requires more than ordinary care. Elevator rope can be obtained in four principal grades: 1) iron. 2) traction steel, 3) high-strength steel, and 4) extra-high-strength steel. In addition. bronze rope is sometirnesused for a limited number of functions within this category. It should be noted that demand for the iron grade is decreasing markedly and its use is gencralJy limited to older existing equipment.

'.

...

14

"'-

..

Figure 9. Cross-sections of some commonly used wire rope constructions.

6,7 WITH FIBER CORE

6

x7

CLASSIFICATION

... .. . .

......... .... ...... ........ .. .. . ... ........ -:.....•.. •..... ... .......... .....•..•.....• ......•.. ................•..•..

.!•

••••• ••••••••••••••• eA•: '•.• •••t. ' :••• ••

:.: • !.!• • ...•• ,-, .:e:• - •• :!:;~:::: ••• :..: \e.:e -,' e:e:• ••.•••,.!••...• .:!:•••

~~: ,}'.::

~oe /.'.e! I!!"G;,&$.

•• ele~~,••• ....~:.,•••f!..! i.:.

:

~

•••

••••• •••••

6xl9 SEALE WITH IWRC

6,25B FLATIENED STRAND TRIANGULAR CENTER WIRE.

:.~~

,

:~:~-:.~ ..

~ ,.: ,:

. .... :... ••••••••••••••• ....e!l.,.... '.. .'1:.-• ... . .. •••••••••••••••••• •••••••••••••• . .-:.:'.. .... .~~!• ••.•! ••.•.•••.•! •

..~:~

,',

·i~.· :::~:~::: ·i~.· :i:::',:::

;.:. . ;

:.~

·.i·'· ~:~

:.~

~

6,26 WARRINGTON SEALE WITH IWRC

6,25 FILLER WIRE WITH IWRC

6x30 G FLATTENED STRAND BRANGLED CENTER • •

.•••. . :. ..•.. .. ... . .....•. :.................... .••·•.•.....•...•. . .•.••..... ....•"....., ... .' •:.!.P •.•.•• .... ...... , .. ...... ••••• • 6 x 19 CLASSIFICATION

• !~• .

••\!•

~~

.... et£.~·

• • • • 2~• •

··~·e;,~-.J1I:~ ••~.·R·.! ..:. •::i::e .•~::..

V~

:.:::.:

• :;:.:.:.:!: •

: :i:·:·:·:i: :

••~,. 0:':::',' ..... .: :::.\ •• ~..... ••~··t ··E············~·· •••••• ~••~:ll• •.•~ •• ~."!.l.! ~~ . •l5.

..~~

.~4!••••.•••• ••'."•••.•• '!.~ , ••.•

:~:::..

.~:!:-:-.

:

..

; •••.•.• • '!

.

• •••••••

~

6,31 FI.LLER WIRE WITH IWRC

.!.

.:,.-:::::::::-1, ••• : :. •

.. .:.-:... . .•....... ..• . .... ......•'..•. :ir:.r.···.··~·~~.~ ..•..•......•

• 6,3i WARRINGTON SEALE WITH'IWRC

~:

:~

6,36 FILLER WIRE WITH IWRC

~~

~.~

~

~~

~:.:~ .:..~...

: •...!'

:

:~

.

..~~~;;/-:•••:i:•••~:.·..:: .:'::. :i:·:-:·:i: .:~.: • • .•.•!'•••••:••••••••.•

.. . ..•...•: . .. ....... ... .. . .. ...

••:••-*;:.:=!:-.:.:••

• •.......•.• :::::::::•• •• :.•.....•.•...••.•..•.• ...... ••••• •••.• ••!te....: ••••••••••••••••••• •.... •.•.....• ..

~:':!J. ~ ~~ ~

~:

~

~

• . •••.•! ••••.•.• .~:.:.'

~

6,41 SEALE FILLER WIRE WITH IWRC

6:x37 CLASSIFICATION

"Also manufactured as 6x27H and 6x25B. ""Also manufactured as 6x27V. 15

.~

~

~

~.:

6,46 SEALE FILLER WIRE WITH IWRC

6,49 FILLER WIRE SEALE WITH FISER CORE

The mostwidely used constructions forelevatoTT9pe are.6x25 FW, ...•.. .•.. 8xI9 Seale, and 8x25 FW. But,on occasion, anumber of other constructions used. In any case, these ropes differ significantly from one another in their wear and fatigue characteristics, thus they should not be inter-changed indiscriminately. There are, in fact, some applications~such as governor rope-where the ropes may not 'be interchanged either in grade or construction without re-qualification. A special construction (6x42) is still used from time to time a~ a hand rope to control the elevator, and small diameter ropes (of 7x 19 construction) are used as control ropes for operating floor selection equipment. From reel to reel, there are slight yet significant differences in the elastic properties of wire rope. Because of such possible variations, it is strongly suggested that all rope for a given elevator be obtained from a single reel. Recognizing the need for such precaution, many codes and purchasing specifications make this a standard requirement. As noted, it is beyond the scope of this publication to discuss, in depth, design and selection considerations for elevator rope. Information concerning sheave diameters, design factors (ratio of nominal strength to working load), groove contours, etc. can be found in the ANSI Code Al 7.1. To obtain current data and sound technical guidance on elevator rope or any other special requirements, a reputable wire rope manufacture~ should be consulted. ,

.. .. • !.

......,. .. :.~

~••p•••••••4!••~

t!:. - .-.f.-• :...•.-•..•........•...• \ .iJ!.:i:.-. :.......:. -\. :.~ ' .. -·-:i:-·- .,...• .;!:••,.,~\!:•• ;.: •••

.... ...

8119 SEALE WITH IWRC

.•.\,. ••.•••1::::.-:-:. :er... .;:.it .eM ••• _\••

... ..-:-.:.-:-

. . ..

••~ ,. -:.-:-.:- eif:-. :::.:.:.::: .:~ ·i~· .-~ ... e!.

.~ yti,

•

"A'! W

8 I Z5 FILLER WIRE WITH IWRC

~** $ .... :l! !fI$

~1~t=-!e l:iji"eO..:::

1817 ROTATION RESISTANT Willi FIBER CORE

19>7 ROTATION RESISTANT WITH WIRE STRANO CORE

."...

a

!

; ,I

are "

~*.~ t;::».et::

b ....

'lSf W ':e I~J7

8119 CLASSIFICATION

.

-O:!:-

1917 CLASSIFICATIONS

Figure 10. Cross-sections of wire ropes designed for specific functions. Note that the two rotation-resistant constructions are identical except for the core--one of which is wire strand and the other fiber. The wire strand core increases the number of strands.from 18 to 19.

16

.1~,

4

Handling Wire Rope RECEIVING, INSPECTION AND STORAGE ·The right time to start appropriate.care and handling procedures for wire rope, is immediately on delivery. When th,e rope arrives it should be carefully checked for size, construction and core, making certain that the delivered product matches the description on the tags, requisition forms, packing slips, purchase order, and invoice. Following these preliminaries, the question of storage should be considered. If the wire rope is to be held for a considerable time before being used, it must be protected from the elements. A dry, well-ventilated building or shed is a proper storage place. Avoid closed, unheated, tightly sealed buildings because . condensation will form on the rope when warm, moist outside air envelops the colder rope. Although wire rope is protected by a lubricant, this is nottotally effective since condensation can still occur within the small interstices between strands and wires, thereby creating corrosion problems. If, on the other hand, the delivery site precludes the use of an inside storage space and the rope must be kept outdoors, it should be suitably covered with a waterproof material. Weeds and tall grass should be cut in the assigned,storage area, and the reel itself should be on a platform, elevated so as to>keep it from direct contact with the ground. Providing an adequate covering f()r the reel will also prevent the original lubricant from drying out with a resuit;:;,rjt loss of protection. Wire rope should never be stored in areas subject to elevated temperatures. Dust, grit or chemically laden atmosphere are also to be avoided. Although the lubricant applied at the factory offers some degree of protection, every normal precaution should be taken with each coil or reel of wire rope. Whenever wire rope remains in position on an idle machine, cr'ane, hoist, etc., it should be coated with an appropriate protective lubricant. In these circumstances, as with ropes stored outside, moisture, in the form of condensation, rain or snow, may form on the wire rope. Some of the moisture may easily become trapped inside the rope and cause corrosion problems. . If the wire rope is to be kept inactive for an extended period while wound on the drum of the idle equipment, it may be necessary to apply a coating of . lubricant to each layer as the rope is wound on the drum; Cleaning, inspection and re-Iubrication should precede start-up of the equipment.

17

WIRE ROPE INSTALLATION CHECKING THE DIAMETER It is most important to check the diameter of the delivered rope before installation.: This is to make certain that the rope diameter meets the specified requirements for the given machine or equipment. With an undersize diameter rope, stresses will be higher than designed for and the probability of breaking the rope will be increased; an oversize diameter rope will wear out prematurely. This happens because of abuse to the rope caused by pinching in the grooves of the sheave and drum. In checking, however, the "true" rope diameter must be measured. And this is defined as the diameter of the circumscribing circle, i.e., its largest cross-sectional dimension. To insure accuracy this measurement should be made with a wire rope caliper using the correct method (b) shown in Fig. 11. For measuring ropes with an odd number of outer strands, special techniques must be employed. Design specifications for wire rope are such that the diameter is slightly larger than the nominal size, accqrdingto the allowable tolerances shown in Table 3. TABLE 3 OVERSIZE LIMITS OF WIRE ROPE DIAMETERS* Nominal Rope Diameter

Thru ;;a"

Allowable Limits -0

+8%

~n"

-0

+7%

Over ~6" thru 1,4 II

-0

+6%

Over 1,4 /I and larger

-0

+5%

Over Ih II thru

*These limits have been adopted by the Wire Rope Technical Board (WRTB). and are being considered for inclusion in the forthcoming revised edition of "Federal Standard RR.W·410." In the case of certain special purpose ropes, such as aircraft cables and elevator ropes, each has specific requirements.

.-~/

"TRUE" DIAMETER

\ ,1~.'.1i .fI'::W" --...... lye.· .~~ ~-a!: ·"81 \...~ • •:l'·", ~

~

\'~11·~\l;" :.:;:-.:~m /

--A

B. CORRECT

C. INCORRECT

Figure 1I. How to measure (or caliper) a wire rope correctly. Since the "true" diameter (a) lies within the circumscribed circle, always measure the larger dimension (b). 18

I

i.

."

UNREELING AND UNCOILING Wire rope is shipped in cut lengths, either in coils or un reels. Great care should be taken when the rope is removed from the shipping package since it can be permanently damaged by improper unreeling or uncoiling. Looping the rope over the head of the reel or pulling the rope off a coil while it is lying on the ground, will create loops in the line. Pulling on a loop will, at the very least, produce imbalance in the rope and may result in open or closed kinks (Fig. 12). Once a rope is kinked, the damage is permanent. To correct this condition, the kink must be cut out, and the shortened pieces used for some other purpose.

Figure 12. Improper handling will help create open (a) or closed (b) kinks. The open kink will open the rope lay; the closed kink will close it. The starlin!! loop Cc): do not allow the rope to form a small loop. If. however. a loop forms and is removed at the point shown, a kink will be avoided. The kink Cd): here the looped rope has been put under tension, the kink has formed, the rope is permanently damaged and is of little value.

19

PREFERRED

REEL

~

ALLOWABLE-

Figure 15. to drum.

IF NOT CLOSE COUPLEO

Winding wire rope from reel

Unwinding wire rope from its reel also requires careful and proper procedure. There a.re three methods to perform this step correctly: 1) The reel is mounted on a shaft supported by two jacks or a roller payoff (Fig. 13). Since the reel is free to rotate, the rope is pulled from the reel by "a workman, holding the rope end and walking away from the reel as it unwinds. A braking device should be employed so that the rope is kept taut and the reel is restrained from over-running the rope. This is necessary particularly with powered de~reeling equipment. 2) Another method involves mounting the reel on an unreeling stand (Fig. 14). It is then unwound in the same manner as described above (I). In this case, however, greater care must be exercised to keep the rope under tension sufficient to prevent the accumulation of slack-a condition that will cause the rope to drop below the lower reel head. 3) In another accepted method, the end of the rope is held while the reel itself is rolled along the ground. With this procedure the rope will payoff properly; however, the end being held will travel in the direction the reel is being rolled. As the difference between the diameter of the reel head and the diameter of the wound rope increases, the speed of travel will increase.

Fi~ute i3.

The wire rope teeI is mounted ona Shaft supported by jacks. This permits the reel to rotate freely. and the rope can be unwound either manually or by a powered mechanism.

20

Figure 14.

A vertical unreeling stand.

When re~reeling wire rope from a horizontally supported reel to a drum, it is preferable for the rope to travel from the top of the reel to the top of the drum; or, from the bottom of the reel to the bottom of the drum (Fig. 15). Re-reeling in this manner will avoid putting a reverse bend into the rope as it is being installed. If a rope is installed so that a reverse bend is induced, it may cause the rope to become livelier and, consequently, harder to handle. When unwinding wire rope from a coil, there are two suggested methods for carrying out this procedure in a proper manner: 1) One method involves placing the coil on vertical unreeling stand. The stand consists of a base with a fixed vertical shaft. On this shaft there is a "swift," consisting of a plate with inclined pins positioned so that the coil may be placed over them. The \vhole swift and coil then rotate as the rope is pulled off. This method is particularly effective when the rope is to be wound on a drum. 2 ) The most common as well as the easiest uncoiling method is merely to hold one end of the rope while rolling the coil along the ground like a hoop (Fig. 16). Figures 17 and 18 show unreeling and uncoiling methods that are most likely to provide kinks. Such improper procedures should be strenuously avoided in order to prevent the occurrence of loops. These loops, when pulled taut, will inevitably result in kinks. No matter how a kink develops, it will damage strands and wires, and the kinked section must be cut out. Proper and carefiirliandIing will keep the wire rope free from kinks.

a

Figure 16. Perhaps the most common and easiest uncoiling method is to hold one end of the rope while the coil is rolled along the ground.

Figure 17. Illustrating a wrong method of unreeling wire rope. 21

Figure 18. Illustrating a wrong method of uncoiling wire rope.

(

SEIZING WIRE ROPE· While there are numerous ways to cut wir~ rope, in every case. certain precautions 'must be observed. For one thing, proper se'izings are always applied on both sides of the place where the cut is to be made. In a wire rope, carelessly or inadequately seized, ends may become distorted and flattened. and the strands may loosen. Subsequently, when the rope is put to work. there may be an uneven distribution of loads to the strands; a condition that will significantly shorten the life of the rope. There are two widely accepted methods of applying seizing (Fig. 19). The seizing itself should be a soft, or annealed wire or strand. The seizing wire diameter and the length of the seize will depend on the diameter of the wire rope. But the length of the seizing should never be less than the diameter of the rope being seized. For preformed rbpes, one seizing on each side of the cut is normally sufficient. But for those that are not preformed. a minimum of two seizings is recommended (Fig. 20). Seizings should be spaced 6 rope diameters apart. Table 4 lists seizing lengths and seizing wire diameters suggested for use with some commonly used wire ropes.

Figure 19. METHOD A: Lay one end of the seizing wire in the groove between two strands; wrap the other end lightly in a close helix over n position of the groove using a seizing iron (a rOl,lnd bar 1/2 " to %" diam. x 18" long) as shown above. Both ends of tbe seizing wire should be twisted together tightly, and tbe finished appearance as shown below. Seizing widths should not be less than the rope diameter. METHOD B: The procedure illustrated at right is the second of the two (A and B) accepted methods for placing seizing on wire rope.

"

TABLE 4 SEIZING Suggested Diameters and Lengths::... .. . Rope Diameters

:;".

Seizing Wire Diameters *

Seizing Lengths

inches

mm

inches

mm

inches

mm

Vs~lj16

3.5-8.0

.032

0.813

~

6.0

%-~6

9.5-14.5

.048

1.21

1,6

13.0

0/8 _10/10

16.0-24.0

.063

1.60

%

19.0

1-1 ~S.6

26,0-33.0

.080

2.03

11.4

32.0

1%-111;10

'35.0-43.0

.104

2.64

1%

44.0

1%-21,6

45.0-64.0

.124

3.15

21,6

64.0

2~0-31,6

65.0-89.0

.124

3.15

3 th

.;; ~.

89.0

*The diameter of seizing wire for elevator ropes is generally smaller than indicated in this table. The wire rope manufacturer should be consulted for recommended,sizes.

23

.J

CUTTING WffiE ROPE " Wire rope is_~ut after being properly seiz~d (Fig. 20). Cutting is a reasonably simple operation provided appropriate tools are used. There are several types of cutters and shears commercially available. These are specifically designed to cut wire rope. Portable hydraulic and mechanical rope cutters are available. In remote areas, however, it may at times be necessary to use less desirable cutting methods. For example, using an axe or hatchet must be recognized as dangerous.

NONPREFORMED

~1111111111111~ BEFORE CUTTING

~Il

~,IIIIlIIIIIII~

AFTER CUTTING

PREFORMED

I

~11111111111111~1111111l111111~ I BEFORE CUTTING

~11111111111111E1 ~1111111111111~ AFTER CUTTING

Figure 20. Seizings, either on non-preformed or preformed wire rope, are applied before cutting.

24

END ATTACHMENTS For a number ofapplications-si.J~h as tight openings in drums. or other complicated reeving systems-there, may be a need for making special end preparations. Wh'en these are required, there are about four basic designs (and combinations) to choose from (Fig. 21 ) . Becket loops are used when another rope is needed to pull the new rope into place. The rope end must be fastened to the mechanism so that force and motion . are transferred efficiently. End fittings thus become items of great importance for transferring these forces. Each basic type of end fitting has its own individual characteristics. Thus, one type will usually fit the needs of a given installation better than the others (Fig. 22). THE EFFICIENCY OF END ATTACHMENTS It should be noted that not all end attachments will develop the full strength of the wire rope used. To lessen the possibility of error, the wire rope industry has determined terminal efficiencies for various types of end attachments. Table 5-listing these efficiencies-permits calculation of the holding: power of the more popular end fittings for any size, grade and constFuction ofi:wire rope. A

PAD EYE

B

LINK BECKET

c

o

TAPERED 8 WELDED END

TAPERED END WITH LOOP

Figure 21. Beckets. or end preparations. are used on wire rope ends when another rope is needed to puJl the operating rope into place. Four commonly used beckets are illustrated.

-""

f
~~~",,-,;,,~~'-,.~~~,=-~ WIRE ROPE SOCKET· SPELTER OR RESIN ATTACHMENT'

WIRE ROPE SOCKET -SWAGED

~-~~--=-~~ MECHANICAL SPLICE- LOOP OR THIMBLE ATTACHMENT

WEDGE SOCKET,

CLIPS - NUMBER OF CLIPS VARIES WITH ROPE SIZE

©llllllllllllllmlmlllllllmnm~~ LOOP OR THIMBLE SPLICE- HAND TUCKED

Figure 22. End fittings. or attachments. are available in many designs. some of which were developed for particular applications. The six shown are among the most commonly used. 26

"~,,,

.' ....... "'-", ~-.,

.-~"--'~~---,~-~-~

..

TABLE 5 TERMINAL EFFICIENCIES (APPROXIMATE)

Efficiencies are based on nominal :strengths

Method of Attachment

. Efficiency Rope with IWRC* Rope with FC**

Wire Rope Socket-Spelter or Resin Attachment '. Swaged Socket Mechanical Spliced Sleeve 1" dia. and smaller 11A3" dia. thru 1 % " 2" dia. and larger

100% 95%

95% 92 Ih% 90%

Loop or Thimble Splice-Hand Spliced (Tucked) (Carbon Steel Rope)' 90% ~" 0/16" 89% 88% %" ~6" 87% 86% 'iZ" 84% %" 82% %" 80% %"thru2'iZ"

100% (Not established)

92V2% 90% 87'iZ %

90% 89% 88% 87% 86% 84% 82% 80%

Loop or Thimble Splice-Hand Spliced (Tucked) (Stainless Steel Rope) ~JI 80% l}16" 79% 78% %" %6" 77%. Ih" 76%' 74% 0/8 " %" 72% %" 70% Wedge Sockets*** (Depending on Design) Clips*** (Number of clips varies with size of rope)

75% to 90%

80%

. *IWRC = Independent Wire Rope Core **FC = Fiber Core ***Typical values when applied properly. Refer to fittings manufacturers for exact values and method.

27

75% to 90%

80%

SOCKETING Impropetly attached wire rop'e te;:rminals lead to serious-possibly unsafeconditicms. To perform 'properly"alI wire rope elements must be held securely by the terminal. If this is not accomplished. the strands will "loaf on the job" and there is every likelihood that a strand will become "high". A high strand condition is illustrated in Figure42. In the case shown. selective abrasive wear of the loose strand will necessitate early removal of the rope.

Poured Sockets-SpeIter or Resin When preparing a wire rope for socketing. it is of extreme importance to follow recommended procedures. (See Appendix D: SOCKETING PROCEDURES.) Procedures other than those stipulated here. may develop the required strength but this cannot be pre-determined without destructive tests. It is far saferand ultimately less costly-to follow well-established practices. There are many ways to go wrong in socketing procedures. Some of the more common pitfalls that should be guarded against include: I ) Turning back the strands-inward or outward-before the "broom" is inserted into the socket; 2) Turning back the strands and seizing them to the body of the rope; 3) Turning back the strands and tucking them into the body of the rope; 4) Tying a knot in the rope; 5) Driving nails, spikes, bolts, and similar objects into the socket after the rope is in, so as to "jam" it tight; this is particularly dangerous-and ruinous. To avoid these and many other dangeroLls practices, play it safe by following correct' procedures.

WIRE ROPE CLIPS

U-BOLT

'''IST'GRIP

Fil:ure 23. Wire rope clips are obtainable in two basic designs: V-bolt and fist grip. Their efficiency is the same.

Wire rope clips are widely used for attaching wire rope to haulages, mine cars, hoists, and for joining two ropes. Clips are available in two basic designs; the V-bolt and fist grip (Fig. 23). The efficiency of both types is the same. When using V-boll clips. extreme care must be exercised to make certain that they are attached correctly. i.e., the V-bolt must be applied so that the "U" section is in contact with the dead end of the rope (Fig. 24). Also. the tightening and retightening of the nuts must be accomplished as required. HOW TO APPLY CLIPS U-BOLT CLIPS (Table 6, page 30) Recommended Method of Applying U-Bolt Clips to Get Maximum Holding P6""ier of the Clip 1 ) Turn back the specified amount of rope from the thimble. Apply the first clip one base width from the dead end of the wire rope (U-bolt over dead end-live end rests in clip saddle). Tighten nuts evenly to recommended torque. 2) Apply the next clip as near' the loop as possible. Turn on nuts firm but do not tighten. 3) ,Space additional clips if required equally between the first two. Turn on nutstake up rope slack'---tighteh alI nuts evenly on alI clips to recommended torque.

4) NOTICEl Apply the initial load and retighten nuts to the recommended torque. Rope will stretch and shrink in diameter when loads are applied. Inspect periodically and retighten. . A termination made in accordance with the above instructions, and using the number of clips shown has an approximate 80% efficiency rating. This rating is based upon the catalog breaking strength of wire rope. 1f a pulley is used in place of a thimble for turning back the rope, add one additional clip. The.number of clips shown is based upon using right regular or lang lay wire rope, 6 x 19 class or 6.x 37 class, fibre core or IWRC, IPS or XIPS. If Seale . construction or similar large outer wire type construction in the 6 x 19 class is to be used for sizes 1 inch and larger, add one additional clip. The number of clips shown also applies to right regular lay wire rope, 8x 19 class, fibre core, IPS, sizes 1 112 inch and smaller; and right regular lay wire rope, 18 x 7 class, fibre core, IPS or XIPS, sizes 1 3,4 and smaller. For other classes of wire rope not mentioned above, it may be necessary to add additiqnal clips to the number shown. If a greater number of clips are used than shown in the table, the amount of rope turnback should be increased proportionately. ABOVE BASED ON USE OF CLIPS ON NEW ROPE. IMPORTANT: Failure to make a termination in accordance with aforementioned instructions, or failure to periodically check and retighten"lOthe recommended torque, will cause a reduction in efficiency rating.

RIGHT WAY FOR MAXIMUM ROPE STRENGTH

WRONG WAY: CLIPS STAGGERED

WRONG WAY: CLIPS REVERSED

Figure 2';, The correCI way 10 attach U-bolts is shown at the top: the "U" section is in contact with the rope's dead end.

29

\,

TABLE 6*

Min. no. Clip Size

of :tlips

A

B

C

D

E

F

G

H

.22 .25 .31 .38

.72 .97 1.03 1.38

.44 .56 ,50 .75

.47 .59 .75 .88

.41 .50 .66 ..72

.38 .44 .56 .69

.81 .94 1.19 1.31

.94 1.16 1.44 1.69

2 '2 2 2

.44· .50 .50 .56

1.50 1.88 1.88 2.25

.75 1.00 1.00 1.25

1.00 1.19 1.19 1.31

.91 1.03 1.13 1.22

.75 .88 ' .88 .94

1.63 1.81 1.91 2.06

1.94 2.28 2.28 2.50

2 2 3 3

% % 'Va

.56 .63 .75 .75

2.38 2.75 3.13 3.50

1.25 1.44 1.63 1.81

. 1.31 1.50 1.75 1.88

.2.06 '·2.50 2.84 2.25 2.44 . 3.16 3.47 2.63.

1~

1~

.75 .88 .88 .88

3.88 4.25 4.63 4.94

2.00 2.13 1.31 2.38

2.00 2.31 2.38 2.59

1.91 2.19 2.31 '2..53

1.25 1.44 1.44 1.44

2.81 3.13 3.13 3.41

10/8 1% 2 2 1,4

1.00 1.13 1.25 1.25

5.31 5.75 6.44 7.13

2.63 2.75 3.00 3.19

2.75 3.06 3.38 3.88

2.66 2.94 3.28 . 3.94

1.63 1.81 2.00 2.00

2 Ih 2% 3

1.25 1.25 1.50

7.69 8:31 9.19

3.44 '3.56 3.88

4.13 4.38 4.75

4.44 4:88 5.34

2.00 2,00 2.38

~ ~6 ~

%6 % %6 ~

%6

1

1~

1%

1.34 1.41 1.59· 1.78

"From The Crosby Group 30

.94 1.06 1.25 1.25

Amount of rope to

turn back 3~

3% 4% 5~

6~

Torque

in Ib/ft

Weight

4.5 7.5 15 30

5 9 18 30

Ib/100

12

45 65 65 95

42 70 75 100

3 4 4 5

12 18 19 26

95 130 225 225

100 150 240 250

3.59 4.13 4.19 4.44

6 6 7 7

34 37 44 48

225 360 360 360

310 460 520 590

3.63 3.81 4.44 4.56

4.75 5.28 5.88 6.38

7 7 8 8

51 53 71 73

430 590 750 750

730 980 1340 1570

4.69 5.00 5.3i

6.63 6.88 7.63

9 10 10

84 100 106

750 750 1200

1790 2200 3200

7 1l~

\,

~

.,

FIST GRIP CLIPS (Table 7, on following page) RECOMMENDED METHOD OF APPLYING FIST GRIP CLIPS 1) Turn back the specified amount of rope from the thimble. Apply the first clip one base width from the dead end of the wire rope. Tighten nuts evenly to recommended torque. 2) Apply the next clip as near the loop as possible. Turn on nuts firmly but do not tighten. 3) Space additional clips if required equally between the first two. Turn on nutstake up rope slack-tighten all nuts evenly on all Clips to recommended torque. 4) NOTICEl Apply the initial load and retighten nuts to the recommended torque. Rope will stretch and shrink in diameter when loads are applied. Inspect periodically and retighten. A termination made in accordance with the above instructions, and using the number of clips shown has an approximate 80% efficiency rating. This rating is based upon the catalog breaking strength of wire rope. If a pulley is used in place of a thimble for turning back the rope, add one additional clip. The number of clips shown is based upon using right regular Or lahg lay wire rope, 6 x 19 class or 6 x 37 class, fibre core or IWRC, IPS or EIPS. If Seale construction or similar large outer wire type construction in the 6 x 19 class is to be used for sizes 1 inch and larger, add one additional clip. The number of clips shown also applies to right regular lay wire rope, 8 x 19 class, fibre core, IPS, sizes IIh inch and smaIIer; and right re'gular lay wire rope, 18 x 7 class, fibre core, IPS or EIPS, sizes 1 1/2 and smaIIer. For other classes of wire rClpe not mentioned above, it may be necessary , to add additional clips to the number shown. If a greater number of clips are used than shown in the table, the amount of rope turnback should be increased proportionately. ABOVE BASED ON USE OF FIST GRIP CLIPS ON NEW WIRE ROPE. 1MPORTA NT: Failure to make a termination in accordance with aforementioned instructions, or failure to periodically check and retighten to the recommended torque, will cause a reduction in efficiency rating.

31

,

t-

A

T ..

.~

rET ,-

,.

L 1

~M~-L

TABLE 7*

Clip Size ~0-14

A

B

C

D

E

F

G

H

L Approx.

M

Min. no. Amount of Torque Weight rope to in of Ib/ft Ib/l00 clips turn back N 30 30 45 65

21 26 37 60

16

65 130 130 225

60 110 110 140

4 5 5 6

26 37 41 55

225 225 360 360

220 270 300 410

6 6

62 66

500 500

680 680

.25 .31 .38 .50

1.25 1.34 1.59 1.88

.34 ,44 .50 .56

.94 1.06 1.06 1.25

.38 .38 ,44 .50

.50 .63 .75 1.00

1.28 1.47 1.81 2.19

.22 .19 .25 .28

1.63 1.94 2.38 2.75

.69 .69 .75 .88

1.47 1.56 1.88 2.19

2 2 2 2

4 5

%0 % %

.50 .63 .63 .75

1.88 2.28 2.28 2.69

.56 .69 .69 .88

1.25 .. .50 1.50 .63 1.50 .63 1.81 .75

1.00 1.25 1.25 1.50

2.19 2.69 2.69 2.94

.28 .28 .28 .31

2.75 3.50 3.50 3.75

.88 1.06 1.06 1.25

2.19 2.63 2.63 3.06

3 3 3 3

11 12%

'Va 1 Bis 114

.88 1.00 1.13 1.25

2.97 3.06 3.44 3.56

.97 1.19 1.28 1.34

2.13 2.25 2.38 2.50

.75 1.75 .75 2.00 .88 ·2.25 .88 2.50

3.31 3.72 4.19 4.25

.38 ,41 ,44 .50

4.13 4.63 5.25 5.25

1.25 1.25 1.44 1.44

3.14 3.53 3.91 4.03

1% 1Y.z

1.50 1.50

4.13 4.13

1.56 1.56

3.00 3.00

5.56 5.56

.56 .56

7.00 7.00

1.63 1.63

4.66' 4.66

0/10 % ~6 ~

1.00 1.00

3.00 3.00

*From The Crosby Group

32

5~

6112

13~

\

I

'"

~l

WEDGE SOCKETS One of the more popular end attachments for wire rope is the wedge socket. For field, or on the job attachment, It is easily instaIJed and quickly dismantled. The procedure is simple: ' 1) Inspect the wedge and socket; all rough edges or burrs, that might damage the rope, should be removed. 2) If the end of the rope is welded, the welded end should be cut off. This will allow the distortions of the rope strands, caused by the sharp bend around the wedge, to adjust themselves at the end of the line. If the weld is not cut off, the distortions will be forced up the working line. This may result in the development of high strands and wavy rope. 3) Place the socket in an upright position and. bring the rope around in a large, easy to handle, loop. Care must be taken to make certain that the live-Ioadedside of the rope is in line with the ears (Fig. 25). 4) The dead end of the rope should extend from the socket for a distance approximately nine times the rope diameter. The wedge is now placed in the socket, and a wire rope clip is placed around the dead end by clamping a short, extra piece of rope to the tail. (Do not clamp to the live part.) The V-bolt should bear against the tail; the saddle of the clip should bear against the short extra piece. i' 5) Secure the ears of the socket to a sturdy support and carefully take a strain on the live side of the rope. Pull the wedge and rope into position.. with tension sufficiently tight to hold them in place. 6).After final pin connections are made, increase the loads gradually until the wedge is properly seated. Avoid sudden shock loads. The foregoing is the recommended procedure. If variations are made to suit special conditions, they should be carefully evaluated beforehand.

~ LIVE END---....

Figure 25. The wedge socket is a very popular end attachment; it is easily installed and quickly dismantled. But it must be applied correctly (A).

A

RIGHT

33

B

WRONG

DRUMS-GROOVED Drums are the means by which power is transmitted to the rope and thence to the object to be moved. For the wire rope. to pick up this power efficiently and to transmit it properly to the working end, installation must be carefully controlled. If the drurn is grooved, the winding conditions should be closely supervised to assure adherence to the following recommended procedures: 1) the end of the rope must be secured to the drum by such means as will give the end attachment at least as much strength as is specified by the equipment manufacturer. 2) Adequate tension must be maintained on the rope while it is being wound so that the winding proceeds under continuous tension. 3) The rope must follow the groove. 4) There should be at least three dead turns remaining on the drum when the rope is unwound during normal operation. Two dead turns are a mandatory requirement in many codes and standards. If the wire rope is carelessly wound and, as a result, jumps the grooves, it will be crushed and cut where it crosses from one groove to the other. Another, almost unavoidable problem is created at the drum flange; as the rope climbs to a second layer there is further crushing and the wires receive excessive abrasion. Riser and filler strips may help remedy this condition. \.

34

DRUMS-PLAIN (SMOOTH) Installation of a wire rope on a pl~in (smooth) face drum requires a great deal of care. The starting position s1.?ould be at the drum end so that each tum of the rope will wind tightly against the preceding turn (Fig. 26). Here too, close supervision should be maintained all during installation. This will help make . certain that: 1) the rope is properly attached to the drum, 2) appropriate tension on the rope is maintained as it is wound on the drum, 3) each turn is guided as close to the preceding turn as possible, so that there are no gaps between turns, 4) and that there are at least two dead turns on the drum when the rope is fully unwound during normal operating cycles. Loose and uneven winding on a plain- (smooth-) faced drum, can and usually does create excessive wear, crushing and distortion of the rope. The results of such abuse are lower operating performance, and a reduction in the rope's effective strength. Also, for an operation that is sensitive in terms of moving and spotting a load, the operator will encounter control difficulties a~ the rope will pile up, puU into the pile and faU"from the pile to the drum surface;: The . ensuing shock can break or otherwise damage the rope.

L-

L- -R

-R

-H-----

UNDERWIND LEFT TO RIGHT USE LEFT LAY ROPE

L-

I

-R

~~-

LEFT LAY UNDERWOUND

L--

----++±{1-

OVERWIND LEFT TO RIGHT USE RIGHT LAY ROPE

OVERWIND RIGHT TO LEFT USE LEFT LAY ROPE

-R

LEFT LAY OVERWOUND

I

++-----

RIGHT LAY OVERWOUND

Fj~re

UNDERWIND RIGHT TO LEFT USE RIGHT LAY ROPE

R1GHT LAY UNDERWOUND

26. By holding the right or left hand with index finger extended. palm up or palm down, the proper procedure for installing lefT- and righT-lay rope on a smooth drum can be easily determined.

35

The proper direction of winding the first layer on a smooth drum can be determined by standing behind the drum and looking along the path the rope travels, and then following one oLthe procedures illustrated in Figure 26. The diagrams show: the correct relationship that should be maintained between the direction of lay of the rope (right or left), the direction of rotation of the drum (overwind or underwind), winding from left to right or right to left.

L-

-R

CROSS OVER

Figure 27. After the first layer is wound on a drum. the point at which the rope winds back for each turn is called the cross-over.

DRUMS-MULTIPLE LAYERS Many installations are designed with requirements for winding more than one layer of wire rope on a drum. Winding multiple layers presents some further problems. The first layer should wind in a smooth, tight helix which, if the drum is grooved, is already established. The grooves allow the operator to work off the face of the drum, and permit the minimum number of dead turns. A smooth drum presents an additional problem, initially, as the wire rope must be wound in such a manner that the first layer will be smooth and uniform and will provide a firm foundation for the layers of rope that will be wound over it. The first layer of rope on the smooth drum should be wound with tension sufficient to assure a close helix--each turn being wound as close as possible to the preceding turn-and most, if not all, of the entire layer being used as dead turns. The first layer then acts as a helical groove which will guide the successive layers. Unlike wire ropes operating on groove drums, the first layer should not be unwound from a smooth-faced drum with multiple layers. After the rope has wound completely across the face of the drum (either smooth or grooved), it is forced up to a second layer at the flange. The' rope then winds back across the drum in the opposite direction, lying in the depression between the turns of the rope on the first layer. Advancing across the drum on the second layer, the rope, following the "grooves"'formed by the rope on the first layer, actually winds back one turn in each revolution of the drum. The rope must then cross two rope "grooves" in order to advance acrOss the drum for each turn. The point at which this occurs is known as the cross-over. Cross-over is unavoidable on the second, and all succeeding layers. Figure 27 illustrates the winding of a rope on the second layer from left to right, and from right to left-the direction is shown by the arrows. At these cross-over points, the rope is subjected to severe abrasion and crushing as it is pushed over the two rope "grooves" and rides across the crown of the first rope layer. The scrubbing of the rope, as this is happening, can easily be heard. There is, however, a special drum grooving available that will greatly minimize the damage that can occur atcross-over points. Severe abrasion can also be reduced by applying the rule for the correct rdpe lay (right- or left-lay) to the second layer rather than to the first layer. It is for thiS reason that the first layer of a smdoth drum should be wound tight and used as dead turns.

36

'"

5 Operation and Maintenance of Wire Rope

37

TABLES MAXIMUM ALLOWABLE RADIAL BEARING PRESSURES OF ROPES'ON , VARIOUS SHEAVE MATERIALS (pOUNDS PER SQUARE INCH--PSI):' >',OJ

Material

Flattened Strand Lang Lay, 6 x 19 6 x 37 psi

Lang Lay Rope, psi

Regular Lay Rope, psi

Remarks

6x7

6 x 19

6x37

8 x 19

6x7

Wood

150

250

300

350

165

275

330

400

On end grain of beech, hickory, gum.

Cast tron

300

480

585

680

350

550

660

800

Based on minimum Brinell hardness of 125.

Carbon Steel Casting

550

900

1,075

1,260

600

1,000

1,180

1,450

30-40 Carbon. Based on minimum Brinell hardness of 160.

Chilled· Cast Iron

650

1,100

1,325

1,550

715

1,210

1,450

1,780

Not advised unless surface is uniform in hardness.

Manganese Steel

1,470

2,400

3,000

3,500

1,650

2,750

3,300

4,000

Grooves must be ground and sheaves balanced for high-speed service.

38

\ .....

Values for the allowable unit radial pressures given in Table 8 are intended solely as a user's guide. And use of these figures does not guarantee prevention of any trouble. Further, the values should not be taken as restrictive with regard to other or new materials. There are, for example, certain elastomers in current use that are apparently providing excellent service, but since there is insufficient data to support specific recommendations, such products are not mentioned. BENDING WIRE ROPE OVER SHEAVES AND DRUMS Sheaves, drums and rollers must be oia correct design if optimum service is to be obtained from both the equipment and the wire rope. Because there are many different types of equipment and many different operating conditions, it is .. difficult to identify the one specific size of sheave or drum most economical for every application. The rule to follow is this: the most economical design is the one that most closely accommodates the limiting factors imposed by the operating conditions and the manufacturer's recommendations. All wire ropes operating over sheaves and drums are subjected to cyclic bending stresses, hence the rope wires will eventually fatigue. The magnitude of these stresses depends-all other factors being constant-uponthe.ratioof the diameter oithesheaveor drum to the diameter of the rope. Frequently, fatigue from cyclic, high-magnitude bending stress is the principalEeason for shortened rope service. To illustrate, in order to bend around a sheave, the rope's strands and wires must move relative to one another. This movement compensates for the difference in diameter between the underside and the top side ofthe rope, the distance being greater along the top side than it is on the underside next to the groove. Proper rope action (and service) is adversely affected if shifting the wires cannot compensate for this situation. Also, there can be additional motion retardation because of excessive pressure caused by a sheave whose groove diameter is too small, or by a lack of lubrication. Changing the bending direction from one sheave to another should be scrupulously avoided as this reverse bending still further accelerates wire fatigue. The relationship between sheave diameter and rope diameter is a critical factor that is used to establish the rope's fatigue resistance or relative service life. It is expressed in the tread D/ d ratio mentioned earlier in which D is the tread diameter of the sheave and d is the diameter of the rope. Table 9 lists "suggested" and "minimum" values for this ratio for various rope constructions. Tables 10 and 11 show the effect of rope constructions and D/ d ratios on service life.

39

.. )

TABLE 9 , RECOMMENDED SHEAVE AND DRUM RATIOS

Construction 6x 7 19 x 7 or 18 x 7 6 x 19 Seale 6x25B 6x27H 6x30G 6 x 21 filler wire 6 x 25 filler wire· 6 x 31 Warrington Seale 6 x 36 Warrington Seale 8 x 19 Seale 8 x 25 filler wire 6 x 41 Warrington Seale 6 x 42 Tiller *D

=tread diameter of sheave

Suggested D/d* ratio

Minimum D/d* ratio

72

42 34 34 30 30 30 30 26 26 23 27 21 21 14

51 51 45 45 45 45 39 39 35 41 32 32 21 d

=nominal diameter of rope

To find any recommended or minimum sheave tread diameter from the above table, the ratio for the construction rope to be used is multiplied by its nominal diameter (d). For example: The minimum sheave tread diameter for a Y2" 6 x 21 FW rope would be Vz inch (nominal diameter) x 30 (minimum ratio) Or 15 inches. Note: These values are for reasonable service. Other, different. values are permitted by various standards such as ANSI. API, PCSA, etc. Smaller values mean shorter life.

40

I

\",

TABLE 10 RELATIVE BENDING LIFE F~CTORS Rope Construction

Rope Construction

Factor

6x7 18 x 7 6 x 19 S 6 x 30 Style G 6 x 25 Style B 6 x 21 FW 6x25FW

.57 .67 .80 .80 .80 .92 1.00

Factor

6 x 31 WS 6 x 36 WS 8 x 25 FW 6 x 41 SFW 6 x 43 FWS 6 x 49 SWS 6 x 42 Tiller

1.09 1.31 1.39 1.39 1.54 1.54 2.00

If a change in construction is being considered as a means of obtaining longer service on a rope influenced principally by bending stresses. the table of factors may be useful. For example: a change from a 6 x 25 FW with a factor of 1.00 to a 6 x 36 WS with a factor of 1.31 would mean the service life could be expected to increase 1.31 times or 31 %. It must be pointed out however that these factors apply only for bending stresses. Other factors which may contribute to rope deterioration have not been considered .

. SERVICE LIFE CURVE FOR VARIOUS Old RATIOS 100

! 90 1

!

eo w

70

u.

.!

! i I

!

,

:::i w

u 60

> a:

!

I I I I

I

!

I

! !

I

i

II)

w50 Q.. o a:

a: 30

Figure 28. This service life curve only takes into account bending and tensile stresses. Its applicability can be illustrated by the following example: A rope working with a Did ratio of 26 has a relative service life of 17. If the same rope works over a sheave that increases its Did ratio to 35, the relativ~ service life increases to 32. In short, this rope used on a larger sheave, increases its service life from 17 to 32--or 88%.

I

I

i

I

!/

j

I

!

I I I

!

I

i 1

/~

i

/

i

10

..v-

I

V

/

:/ / /i, !

i

!

! i

'/

I ;

!

/1

V

i

/

/

I

1

i/ /1

I

~

41

I

,

,

10

!

•

i

! 20

II

I

i

I

!i ...J

i

!

w > 40

W

I

!

I I

I

I

i I

i

w

!

I

i

I

!

I

!

I

I

30 Old RATIO

40

i

i 20

50

60

( \

INSPECTION OF SHEAVES AND DRUMS Under normalconditions, machines receive periodic inspections, and their over-all condition is recorded. Such inspections usu~lly include the drum, sheaves, and any other parts that may come into contact with the wire rope and sUbject it to wear. As an additional precaution, rope-related working parts, particularly in the areas described below, should be re-inspected prior to the installation of a new wire rope. The very first item to be checked when examining sheaves, rollers and drums, is the condition of the grooves (Figs. 29,30, and 31). To check the size, contour and amount of wear, a groove gage is used. As shown in Figure 29, the gage should contact the groove for about 150 0 of arc. . Two types of groove gages are in general use and it is important to note which of these is being used. The two differ by their respective percentage

A

over nominal.

c

B

Figure 29. Cross-sections illustrating 3 sheave-groove conditions revealed by the metric arrangement of wires in the strand. tight; and C is too loose.

For new or re-machined grooves, the groove gage is nominal plus the full oversize percentage. The gage carried by most wire rope representatives today is used for worn grooves and is made nominal plus ~ the oversize percentage. This latter gage is intended to act as a sort of "no-go" gage. Any sheave with a. groove smaller than this must be re-grooved or, in all likelihood, the existing rope will be damaged. When the sheave is re-grooved it should be machined to the dimensions for "new and machined" grooves given in Table 11. This table lists the requirements for new or re-machined grooves, giving the groove gage diameter in terms of the nominal wire rope diameter plus a percentage thereof. Similarly; the size of the "no-go" gage is given, against which worn grooves are judged. Experience has clearly demonstrated that the service life of the wire rope will be materially increased by strict adherence to these standards.

A

o

B

c

Figure 30. Th.ese sheave-groove crosssections represent 3 wire rope seating conditions: A. a new rope in a new groove; B. a new rope in a worn groo"e; and C. a worn rope in a worn groove. (See also Figs; 29 and 31.)

GROOVE GAGE

Figure 31.

42

11Iustrating the various dimensions of a s~~ave. and the lise of a.~roove gage.

\,

TABLE 11 MINIMUM SHEAVE- AND DRUM-GROOVE DlMENSIONS*

~""~"

Groove Radius

Nominal Rope Diameter

2 mm

3 inches

4 mm

5 inches

;I.;

6.5 8.0 9.5 11 13

.137 .167 .201 .234 .271

3.48 4.24 5.11 5.94 6.88

.129

.160 .190 .220 .256

3.28 4.06 4.83 5.59 6.50

14.5 16 19 22 26

.303 .334 .401 .468 .543

7.70 8.48 10.19 11.89 13.79

.288 .320 .380 .440 .513

7.32 8.13 9.65 11.18 13.03

29 32 35 38 42

.605 .669 .736 .803 .876

15.37 16.99 18.69 20.40 22.25

.577 .639 .699 .759 .833

14.66 16.23 17.75 19.28 21.16

2;1.;

45 48 51 54 58

.939 1.003 1.070 1.137 1.210

23.85 " 25.48 27.18 28.88 30.73

.897 .959 1.019 1.079 1.153

22.78 24.36 25.88 27.41 29.29

2% 2lh 2% 234 2%

61 64 67 71 74

1.273 2.338 1.404 1.481 1.544

32.33 33.99 35.66 37.62 39.22

1.217 1.279 1.339 1.409 1.473

30.91 32.49 34.01 35.79 37.41

3 3;.s 3 1,4 3% 3 1h

77 80 83 87 90

1.607 1.664 1.731 1.807 1.869

40.82 42.27 43.97 45.90 47.47

1.538 1.598 1.658 1.730 1.794

39.07 40.59 42.11 43.94 45.57

334 4 4 1h 4 34

96 103 109 " 115 122

1.997 2.139 2.264 2.396 2.534

50.72 54.33 57.51 60.86 64.36

1.918 2.050 2.178 2.298 2.434

48.72 52.07 55.32 58.37 61.82

5 5 1,4 5lh 534 6

128 135 141 148 154

2.663 2.804 2.929 3.074 3.198

67.64 71.22 . 74.40 78.08 81.24

2.557 2.691 2.817 2.947 3.075

64.95 68.35 71.55 74.85 78.16

~16

% 34 %

1 PAl 1;1.;

1% 1'h 1% 134 IV!! 2 2;.s

Further. the dimensions do not apply to traction-type elevators: in this circumstance. drum- and sheave-groove tolerances should conform to the elevator manufacturer's specifications.

'

STRAND

~11

'00

W OJ

FLATTENED

t

I

I

~

"':;:

~-

;5-

I I

I

I

I

I

I

I I

I

I

I J I

/ /

I

I

1

Vl

I

I

I

::>

::>

I

I

a:: i..~

to

,

w

a::

3-

I I

I

I

I

I

I

I UNITS OF ROPE LIFE

Figure 35. This curve is plotted to show the relationship of wire rope stretch to the various stages of a rope's life.

53

3) Reduction in rope diameter

,

Any marked reduction in rope diamete~ indicates degradation. Such reduction may be attributed to:

excessive external abrasion internal or external corrosion loosening or tightening of rope lay inner wire breakage rope stretch ironing or milking of strands In the past, whether or not a rope was allowed to remain in service depended to a great extent on the rope's diameter at the time of inspection. Currently this practice has undergone significant modification. Previously, a decrease in the rope's diameter was compared with published standards of minimum diameters. The amount of change in diameter is, of course, useful in assessing a rope's condition. But, comparing this figure with a fixed set of values is, for the most part, useless. These long-accepted minima are not, in themselves, of any serious significance since they do not take into account such factors as: 1) variations in compressibility between IWRC and Fiber Core; 2) differences in the amount of reduction in diameter from abrasive wear, or from core compression, or a combination of both; and 3) the actual original diameter of the rope rather than its nominal value. As a matter of fact, all ropes will show a significant reduction in diameter when a load is applied. Therefore, a rope manufactured close to its nominal size may, when it is subjected to loading, undergo a greater reduction in diameter than that stipulated in the minimum diameter table. Yet, u~der these circumstances, the rope would be declared unsafe although it may, in actuality, be safe. As an example of the possible error at the other extreme, we can take the case of a rope manufactured near the upper limits of allowable size. If the diameter has reached a reduction to nominal or slightly below that, the tables would show this rope to be safe: But it should, perhaps, be removed. Today, evaluations of the rope diameter are first predicated on a comparison bf the original diameter-when new and subjected to a known load-with the current reading under like circumstances. Periodically, throughout the life of the rope, the actual diameter should be recorded when the rope is under equivalent loading and in the same operating section. This procedure, if followed carefully, reveals a common rope characteristic: after an initial reduction, the diameter soon stabilizes. Later, there will be .a continuous, albeit small, decrease in diameter throughout its life. Core deterioration, when it occurs, is revealed by a more rapid reduction in diameter and when observed it is time for removal. Deciding whether or not a rope is safe is not always a simple matter. A number of different but interrelated conditions must be evaluated. It would be

"j

54

dangerously unwise for an inspector to declare a rope safe for continued service simply because its diameter had not reached the minimum arbitrarily established in a table if, at the same time, other observations lead to an opposite conclusion. Because criteria for removal are varied, and because diameter, in itself, is a vague criterion, the table of minimum diameters has been deliberately omitted from this manual. 4) Corrosion Corrosion, while difficult to evaluate, is a more serious cause of degradation than abrasion. Usually, it signifies a lack of lubrication. Corrosion will often occur internally before there is any visible external evidence on the rope surface. Pitting of wires is a cause for immediate rope removal. Not only does it attack the metal wires. but it also prevents the rope's component parts from moving smoothly as it is flexed. Usually, a slight discoloration because of rusting merely indicates a need for lubrication. Severe rusting, on the other hand, leads to premature fatigue failures in the wires necessitating the rop~'s immediate removal from service. When a rope shows more than one wire failure adjacent to a terminal fitting,,it should be removed immediately. To retard corrosive deterioration, the rope should be kept well lubricated. In situations where extreme corrosive action can occur, it may be necessary to use galvanized wire rope. 5) Kinks Kinks are permanent distortions caused by loops drawn too tightly.:Ropes with kinks must be removed from service. 6) "Bird Caging" Bird caging results from torsional imbalance that comes about because of mistreatments such as sudden stops, the rope being pulled through tight sheaves, or wound on too small a drum. This is cause for rope replacement unless the affected portion can be removed. 7) Localized Conditions Particular attention must be paid to wear at the equalizing sheaves. During normal operations this wear is not visible. Excessive vibration, or whip can cause abrasion and/ or fatigue. Drum cross-over and flange point areas must be carefully evaluated. All end fittings. including splices, should be examined for worn or broken wires, loose or damaged strands, cracked fittings, worn or distorted thimbles and tucks of strands. 8) Heat Damage After a fire, or the presence of elevated temperatures, there may be metal discoloration. or an apparent loss of internal lubrication; fiber core ropes are particularly vulnerable. Under these circumstances the rope should be replaced. 9) Protruding Core If. for any cause. the rope core protrudes from an opening between the strands the rope is unfit for service.

55

10) Damaged End Attachments Cracked, bent, or broken end fittings must be eliminated. The cause should be sought out and corrected. In the case of bent hooks, the throat openings -measured at the narrowest'point-should not exceed 15 % over normal nor should twisting be greater than 10°. 11) Peening Continuous pounding is one of the causes of peening. The rope strikes against an object such as some'structural part of the machine, or it beats against a roller, or it hits itself. Often, this can be avoided by placing protectors between the rope and the object it is striking. Another common cause of peening is continuous passage-under high tension-over a sheave or drum. Where peening action cannot be controlled, it is necessary to have more frequent inspections and to be ready for earlier rope replacement. Figure 36 shows the external appearance of two ropes, one of which has been abraded and the other peened. Also shown are the cross-section of both wires in these conditions.

peening

abrasion

Figure 36. These plan views and cros~ sections show the effects of abrasion and peening on wire rope. Note that a crack has formed as a result of heavy peening.

56

12) Scrubbing Scrubbing refers to the displacement of wires and strands as a result of rubbing around or against an object. This, in turn, causes wear and displacement of wires and strands along one side of the rope. Corrective measures should be taken as soon as this condition is observed. 13) Fatigue Failure Wires that break with square ends and show little surface wear, have usually failed as a result of fatigue. Such failures can occur on the crown of the strands, or in the valleys between the strands where adjacent strand contact exists. In almost all cases, these failures are related to bending stresses or vibration. If diameter of the sheaves, rollers or drum cannot be increased, a more flexible rope should be used. But, if the rope in use is already of maximum flexibility, the only remaining course that wiil help prolong its service life is to move the rope through the system by cutting off the dead end. By moving the rope through the system, the fatigued sections are moved to less fatiguing areas of the reeving. This technique is most frequently used in rotary drilling. 14) Broken Wires The number of broken wires on the outside of a wire rope are 1) an index of its general condition:, and 2) whetheror not it must be considered for replacement. Frequent inspection will help determine the elapsed time between breaks. Ropes should be replaced as soon as the wire breakage . reaches the numbers given in Table 13. Such action must be taken without;,;, regard to the type of fracture.

On occasion, a single wire will break shortly after installation. However, if no other wires break at that time, there is no need for concern. On the other hand, should more wires break, the cause should be carefully investigated. . _On any installation, valley breaks-i.e., where the wire ruptures between strands-should be given serious attention. When two or more such conditions are found, the rope should be replaced immediately. It is well to remember that once broken wires appear-,-in a normal rope operating under normal conditions-a good many more will show up within a relatively short period. Attempting to squeeze the last measure of service from a rope beyond the allowable number of broken wires (Table 13), will create an intolerably hazardous situation. _ A diagnostic guide to some of the most prevalent rope abuses is given in Table 14, On the following pages these abuses are illustrated and described.

57

TABLE 13 WHEN TO REPLACE WIRE ROPE-BASED ON NUMBER QF BROKEN WIRES Number Broken Wires . In Running Ropes ANSI No.

Equipment

In One Rope Lay

In One Strand

12

4

Number Broken Wires In Standing Ropes In One Rope Lay

At End Connection

Not Specified

B30.2

Overhead & Gantry Cranes

B30.4

Portal, Tower & Pillar Cranes

6

3

3

2

B30.5

Crawler, Locomotive & Truck Cranes

6

3

3

2

B30.6

Derricks

6

3

3

2

B30.7

Base Mounted Drum Hoists

6

3

3

2

B30.8

Floating Cranes and Derricks

6

3

3

2

AlO.4

Personnel Hoists

6* .

3

2*

2

AlO.S

'Material Hoists

6*

Not Specified

Not Specified

'" Also remove for 1 valley break.

Fi~te 37.

A wire that has broken under a tensile load in excess of itsstrength. is recognized by the "cup and cone" configuration at the fracture point (A). The necking down of the wire at point of failure shows that failure occurred while the wire retained its ductility. A fatigue break is usually characterized by squared-off ends perpendicular to the wire either straight across or Z-shaped (B & C). 58

TABLE 14 DIAGNOSTIC GUIDE TO COMMON WIRE ROPE ABUSES

Abuse

,.

\...::/

Symptoms

Possible Causes

Fatigue

Wire break is transverse--either straight across or Z shape. Broken ends will appear grainy.

Check for rope bent around too small. a radius; vibration or whipping; wobbly sheaves; rollers too small; reverse bends; bent shafts; tight grooves; corrosion; small drums & sheaves; incorrect rope construction; improper installation; poor end attachments. All running rope if left in service long enough will eventually fail by fatigue.

Tension

Wire break reveals predominantly cup and cone fracture with some 45 0 shear breaks.

Check for overloads; sticky, grabby clutches; jerky cortditions; loose bearing on drum; fast starts, fast stops, broken sheave flange; wrong rope size & grade; poor end attachments. Check for too great a strain on rope after factors of deterioration have weakened it.

Abrasion

Wire break mainly displays outer wires worn smooth to knife edge thinness. Wire broken by abrasion in combination with another factor will show a combination break.

Checkfor change in rope or sheave size; change in load; overburden change; frozen or stuck sheaves; soft rollers, sheaves or drums; excessive· fleet angle; misalignment of sheaves; kinks; . improperly attached fittings; grit & sand; objects imbedded in rope; improper grooving..

Cut or Gouged or Rough Wire

Wire ends are pinched down, mashed and/or cut in a rough diagonal shear-like manner.

Check on all the above conditions for mechimical abuse, or either abnormal or accidental forces during installation.

Torsion or Twisting

Wire ends show evidence of twist and/or cork-screw effect.

Check on all the above conditions for mechanical abuse, or either abnormal or accidental forces during installation.

Mashing

Wires are flattened and spread at broken ends.

Check on all the above conditions for mechanical abuse, or either abnormal or accidental forces during installation.

Corrosion

Wire surfaces are pitted with break showing evidence either of fatigue tension or abrasion.

Indicates improper lubrication or storage.

Abrasion plus Fatigue

Reduced cross-section is broken off square thereby producing a chisel shape.

A long term condition normal to the operating process,

Abrasion plus Tension

Reduced cross-section is necked down as in a cup and cone configuration. Tensile break produces a chisel shape.

A long term condition normal to the operating process.

59

«.

I

Figure 38. An example of interstrand and core-to-strand nicking. A strand (upper member) has been removed from the rope (lower member) to show the equivalent lines of nicking where strands are in contact with one another, as well as with the core.

\.

,.,.,....... ,,-

Fi~~re 39.

A cork-screll'('d rope: the condition Came about asa result of the rope being pulled around an ohject having a small diameter.

60

.-,"

/

Figure 40. When a reel has been damaged in transit, it is a safe assumption that irreparable damage has b.een.dane to the rOj?e.

,"

~-

Figure 41. Wire rope abuses during shipment create serious problems. One of the more common causes is improper fastening of rope end to reel. e.g., nailing Ihro/lgh the rope end. These photos show two acc('prab!(' methods: A) one end of a wire "noose" holds the rope. and the other end is secured to the reel: and B) the rope end is held in place by a l-bolt or V-bolt that is fixed to the reel. 61

Figure 42. socketing.

An example of "high strand". The excessive wear of a single strand is caused by improper

..

.

Figure 43.

This rope was damaged by being rolled over some sharp object.

Figure 44.

These damages were the result of bad drum winding.

62

Figure 45.

This effect of drum crushing is evidence of bad winding conditions.

Figure 46.

A deeply corrugated sheave.

Figure 47.

This rope condition is called a dog leg.

63

Figure 48. An occurrence that is called a popped core.

Figure 49.

This is a typical bird cage condition.

~---~

, Figure 50., Here the strand wires were snagged.

64

'.

,, Figure S1.

the sheave.

65

A very bad condition (spiralling) brought about when the rope jumped from

Figure 52.

This is the appearance of a typical tension break; a result of overloading.

A

B

Figure 53. A) Serious wear resulting from excessive bending. and B) localized wear brought about by poor cut-off practice.

Figure 54. This is an illustration of a seriolls condition where the rope slides over or against itself.

Fi~re 55. An illustration of \'Olley type fatigue breaks. Flexing the rope exposes broken wires hidden in valleys between strands.

66

-\

\

)

ROPE INSPECTION SUMMARY Any wire rope that has broken wires, deformed strands, variations in diameter, or any change from its normal appearance, must be considered for replacement. It is always better to replace a rope when there is any doubt concerning its condition or its ability to perform the required task. The cost of wire rope replacement is quite insignificant when considered in terms of human injuries, the cost of down time, or the cost of replacing broken structures. Wire rope inspection includes examination of basic items such as: 1) Rope diameter reduction 2) Rope lay 3) External wear 4) Internal wear 5) Peening 6) Scrubbing 7) Corrosion 8) Broken wires Some sections of rope can break up without any prior warning. Already discussed in some detail as to cause and effect, sections where this occurs are ordinarily found at the end fittings, and at the point where the rope enters or leaves the sheave groove of boom hoists, suspension systems, or other semioperational systems. Because of the "working" that takes place: at these sections, no appreciable wear or crown breaks will appear. Under such an operation, the core fails thereby allowing the strands to notch adjacent strands.;However, when this happens, valley breaks will appear. As soon as the first vaHey break is detected, the rope should be removed immediately. If preventive maintenance, previously described, is diligently performed, the rope life will be prolonged and the operation will be safer. Cutting off a given length of rope at the end attachment before the core deteriOI:ates and valley breaks appear, effectively eliminates these sections as a source of danger. EQUIPMENT INSPECTION Any undetected fault on a sheave, roller, or drum-be it of relatively major or minor significance-can cause a rope to wear out many times faster than the wear resulting from normal operations. As a positive means of minimizing abuses and other-than-normal wear, the procedures here set forth should be adhered to. Every observation and measurement should be carefully recorded and kept in some suitable and accessible file. 1) Give close examination to the method by which the rope is attached both to the drum and to the load. Make certain that the proper means of attachment is applied correctly, and that any safety devices in use are in satisfactory working order.

0'

r'"

~~.

67

2) Carefully check the groove and working surface of every sheave, roller, and drum, to determine whether each (groove and surface) is as near to the ~orrect diameter and contour as circumstances will permit, and whether all surfaces that are in contact with the rope are smooth and free of corrugations or other abrasive defects. 3) Check sheaves and rollers to determine whether each turns freely, and whether they are properly aligned with the travel ofthe rope. All bearings must be in good operating condition and furnish adequate support to the sheaves and rollers. Sheaves that are permitted to wobble will create additional forces that accelerate the deterioration rate of the rope. 4) If starter, filler, and riser strips on drums are used, check their condition and location. shouid these be worn, improperly located or badly designed, they will cause poor winding, dog legs, and other line damage. 5) Wherever possible, follow the path that the rope will follow through a complete operating cycle. Be on the lookout for spots on the equipment that have been worn bright or cut into by the rope as it moves through the system. Ordinarily, excessive abrasive wear on the rope can be eliminated at these points by means of some type of protector or roller.

FIELD LUBRICATION During fabrication, ropes receive lubrication; the kind and amount depending on the rope's size, type, and anticipated use. This in-process treatment will provide the finished rope with ample protection for a reasonable time if it is stored under proper conditions. But, when the rope is put into service, the initial lubrication may be less than needed for the full useful life of the rope. Because of this possibility, periodic applications of a suitable rope lubricant are necessary. Following, are the important characteristics of a good wire rope lubricant: 1) It should be free from acids and alkalis, 2) It should have sufficient adhesive strength to remain on the ropes, 3) It should be of a viscosity capable of penetrating the interstices between wires and strands, 4) It should not be soluble in the medium surrounding it under the actual operating conditions, 5) It should have a high film strength, and 6) It should resist oxidation.

68

Before applying lubrication, accumulations of dirt or other abrasive material should be removed from the rope., Cleaning is accomplished with a stiff wire .brush and solvent, and compressed,air or live steam. Immediately after it is cleaned, the rope should be lubricated. When it is normal for the rope to operate in dirt, rock or other abrasive material, the lubricant should be selected with great care to make certain that it will penetrate and, at the same time, will not pick up any of the material through which the rope must be dragged. As a general rule, the most efficient and most economical means to do field lubrication/protection is by using some method or system that continuously applies the lubricant while the rope is in operation. Many techniques are used; these include the continuous bath, dripping, pouring, swabbing, painting, or where circumstances dictate, automatic systems can be used to apply lubricants either by a drip or pressure spray method (Fig. 56).

I PAINTING

CONTINUOUS BATH POURING SWABBING DRIPPING

SPRAY NOZZLE

,.. Fi~re 56. Lubricant application methods in general use today include continuous bath, dripping, pouring, swabbing, painting, and spraying. The arrows indicate the direction in which the rope is moving.

69

.-'." ..

, .,~

WIRE ROPE EFFICIENCY OVER SHEAVES (TACKLE BLOCK SYSTEM) " Some portion of a wire rope's strength---:'when operating over sheaves-is expended in turning the sheaves and in flexing. This lost strength is not available to lift the load, and in a multi-part tackle block system (Fig. 57) this loss factor can be significant. The load "seen" by the lead line (fast Ilne) under static (no-movement) conditions can be readily calculated if the load is divided by the number of parts of line as expressed in the following fbrmula: Total load (incl. slings, contain.ers, etc.) · 1 d· . F ast 1me oa = No. of parts of line For example, in a four-part system (Fig. 57d) to lift 6000 Ib, the lead line load will equal: . 6000 or 1500 Ib 4

A. ONE· PART LINE

B. TWO·PART LINE

C. THREE· PART LINE

D. FOUR· PART UNE

E. FNE-PART LINE

Figure 57;' Commonly, used single- and multiple-sheave blocks (tackles). Static loading on the rope is: A) equal to, B)Y.2of. C)V., of. D) l,4 of. and E) lis of the supported load. 70

Moreover, if this system has ball or roller bearings in the sheaves~ the lead line load will increase to 1651 lb when the load starts to move. On the other hand, if the sheaves have plain bearings such as bronze bushings, the lead line load will increase to 1851 lb. In an 8-part system with plain bearings, the lead line load jumps from 750 lb to 10861b-an increase of 45%! Derricks often use 8 or more parts in the boom support system. The schematic diagram (Fig. 58) shows 4-part reeving. This system has the same number of sheaves as there are parts of line. The following procedure presumes this condition throughout. Provision for extra lead sheaves are given at the end of this discussion. To calculate the lead-line load, the combined load of the container, contents _and lifting attachments is multiplied by the lead line factor as follows: Lead line load = lead-line factor x load

N=4 5=4

Figure 58. Schematic representation of a four-part reeving system. N the number of parts of line supporting the load (W), and S the number of rotating sheaves.

=

=

TABLE 15 LEAD-LINE FACTORS* Parts of Line

With Plain Bearing Sheaves

1 2 3 4

.917 .568 .395 .309

.962 .530 .360 .275

5 6 7 8

.257 .223 .199 .181

.225 .191 .167 .148

9 10 11 12

.167 .156 .147 .140

.135 .123 .114 .106

13 14 15

.133 .128 _.124

.100 .095 .090

*In using this table. the user should note that it is based on the as:umption that the number of parts of line (N) is equal to the number of sheaves (5). When S exceeds N, refer to the text.

71

With Roller Bearing Sheaves

EXTRA SHEAVE

. 'Fig: 59showsasimilar4-part system with an additional lead-in sheave; In such cases, for each additiorial sheave the tabulated value is multiplied by 1.09 . for plain bearings, or L04 for ariti-frictio)1 bearings. r Example: What is the lead-line factor for a plain bearing tackle block system of 5 parts of line and two extra lead-in sheaves? The tabulated value is .257. Since there are two additional sheaves, the computation is: .305 .257 x 1.09 x 1.09 What is the lead-line load on this system 'Yhen the load is 5000 Ibs? 5000 x .305 - 1525 lb It should be emphasized that the."dead-end" also may "see" this augmented load. Systems in which both rope ends are attached to a drum such as may be founa in overhead cranes are not within the planned scope of this manual. It is suggested, therefore, that information on such systems be obtained directly from a wire rope manufacturer.

=

N'4 5'5

Figure 59. Schematic representation of a 4-part reeving system with an extra (idler) sheave.

72

6 Physical Properties ELASTIC PROPERTIES OF WIRE ROPE Wire rope, an elastic member, derives its normal stretch characteristics from two sources: 1) the inherent elasticity of its metal components, and 2) the compaction process ofits wires, strands and core. There is, moreover, a third source of elongation-under-Ioad: the rope's tendency to rotate and its associated lengthenings of the lay. This rather complex process has potentially dangerous consequences and must be avoided. A discussion ~f elongation brought about by rotation is not included here since it is not within the scope of this publication. Constructional stretch occurs when the rope's elements are compressed, or pulled together, as the load is applied. The result is a slight decrease in diameter and increase in length. This may be likened to the familiar effect known as the "Chinese Finger Trap." As would be expected, ropes that have more compressible cores (e.g., fiber cores) than IWRC or strand core ropes (e.g., 7 x 19 aircraft cable) will exhibit greater constructional stretch. Usually, constructional stretch in IWRC or strand core ropes becomes permanent after several loadings leaving the rope with very little resiliency or recovery. However, fiber core ropes if lightly loaded (elevator ropes) may retain some degree of resiliency throughout most of their service life. The rope's construction, particularly its type of core and the. number of strands, will have a significant effect on constructional stretch. For example, an 8-strand rope has a core diameter averaging 22 % greater than that of a 6-strand rope. The 8-strand rope's constructional stretch is about 50% greater. As to the effect of core type, a 6-strand rope with IWRC has about half (50%) of the constructional stretch of a 6-strand fiber core rope. The load range will also influence the overall stretch. When constructional stretch just about reaches a maximum at 20% loading, the elastic portion will remain almost straight-line up to around 65 % . Total stretch, therefore, as a percent of length is greater from 0 to 20% than from 20 to 65 % because constructional stretch contributes very little above 20% .. To gain some idea of the amount of constructional stretch that may be expected, the following brief tabulation shows some of the percentages:

Rope Construction 6 strand fiber core 6 strand IWRC 8 strand fiber core *Depends on loading.

73

Approx. Range of Stretch*

lh%-%% %%_11'2% %%-1%

Despite the fact that stretchcannofbe calculated precisely, the following formula will provide a close approximati~n sufficient for most situations. Ch· . I . h (ft) ange 10 engt

.

=

'Change i~-load (lb) x Length (ft) Area (inches:!) x Modulus of Elasticity

It should be noted that this formula does not take rotation into account. Example: What approximate elongation per foot may be expected in a ~ "-6 x 41 Warrington Seale Construction IPS IWRC if the load changes from 20% to 30% of its nominal strength? 23,000 x (.3 -.2) Change in load Nominal strength x (.3 -.2) 23,000 x.l 2300lb Modulus of Elasticity (from Table 15) 14,000,000 .1225 Area (from Table 16) -.4902 x (lIz)2 Change in length = 2300 xI _ 0013 ft .1225 x 14,000,000 . Note: A 100 ft piece would stretch 100 times this figure or .13 ft (1.61 inches). Tables 16 and 17 provide approximate modulus of elasticity and metallic area for a number of rope classifications and diameters.

=

=

= =

=

=

TABLE 16 APPROXIMATE MODULUS OF ELASTICITY (pounds per square inch)

Rope Classification 6 x 7 with fiber core 6 x 19 with fiber core 6 x 37 with fiber core 8 x 19 with fiber core 6 x 19 with IWRC 6 x 37 with IWRC

74

Zero to 20% Loading

20% to 65 % Loading

11,700,000 ,10,800,000 ·9,900,000 8,100,000 13,500,000 12,600,000

13,000,000 12,000,000 11,000,000 9,000,000 15,000,000 14,000,000

TABLE 17 APPROXIMATE METALLIC AREAS OF VARIOUS CONSTRUCTIONS Based on 1.03 diameter. If marked by an asterisk (*), area is based on exact nominal diameter.

Construction 1x2 1 x 3* 1 x 7* 1 x 19* 3 x 7*

Centerless

Fiber Core

IWRC

.3927 .5075 .5930 .5827 .3708

""~

5x7 6x6 6x7 6x12 6x1912/7

.3903 ' .3198 .3843 .2319 .3756

.4566 .3861 .4506

6 x 19 S 6x19W 6x21 FW 6x21 S 6x2415/9

.4035 .4156 .4115 .4107 .3292

.4698 .4819 .4778 .4770

6x25 FW 6x26WS 6x27 S 6x29FW 6x3112/9

.4167 .4092

.4830 .4755

.4197 .3852

.4860 .4515

6 x 31 WS 6x33 FW 6x 36 WS 6x3718/19W

.4144 .4232 .4185 .3925

.4807 .4895 .4848 .4588

6x37FW 6x41 SFW 6x41 WS 6 x 42 Tiller 6x43 FWS

.4268 .4246 .4239 .2313 .3920

.4931 .4909 .4902

6x46SFW 6x 46 WS 6x61 FWS 7x7 7x1912/7

.4253 .4257 .4075

.4916 .4920 .4738

.3427 .3325 .3588 .3659

.4740 .4638 .4715 .4972

.3675 .4215

.4988

.4419

6x31 S

.'..'

.; ~ ~~

NOTE: Values given are based on 3% oversize because this is a common design "target." But, this figure often varies and is not to be considered a standard. Wire sizes in specific constructions alw vary, thus the given values are approximate. They are, however, within the range of accuracy of the entire method that is, in itself, approximate.

7x 19W 8x7 8x 1912/7 8x 19 S 8x 19W 8x25FW 18 X 7 19 X 7 6 X 3 X 19 7x7x7 7 X 7 X 19

75

.4583

.4706 .4662 .5051

.4526 .1220 .3425 .3614

Where it is necessary to have precise data on elastic.characteristics, aload vs. elongation test must be performed on a representative sample of the rope under consideration. For certain applications, ropes may be pre-stretched in order to remove some of the constructional stretch. Frequently, this treatment is used on structural members such as bridge rope and strand. In some cases, pre-stretching is applied to operating ropes where elongation may present problems, e.g., elevator and skip hoist ropes. While a pre-stretching technique has value, some of the benefit is lost in reeling and handling.

DESIGN FACTORS Earlier, in this publication, the design factor was defined as the ratio of the nominal breaking strength of a wire rope to the total load it is expected to carry. Hence, the design factor that is selected plays an important part in determining the rope's service life. Excessive loading, whether continuous or sporadic, will greatly impair its serviceability. Usual1y, the choice of a certain wire rope size and grade will be based on static loading and, under static conditions, it is sufficient for its task. However, where a machine is working and dynamic loads . are added to the static load, it is quite possible to exceed the material's elastic limit. As was noted in the earlier discussion, a "common" design factor is 5. Figure 60, the Wire Rope Relative Service Life Curve, shows how the service life is reduced as operating loads are increased. A change in the design factor from 5 to 3 decreases its life expectancy index from 100 to 60-a drop of 40%!

170

I

160

I

150

I

140

'"

i

I

130

i

!!: 120 ..J

i

tjllO

./y

;

I

~

~

~

./ ~ 100 ~---~---~-------~ ; ... ,. /1 en '" 90 ~ ! '"...~80 i /" ~ 70 I 1/ '" "'60 ! 50

,

40

30 20 10

oV I

/

./I

/'

I

I

!

:

/

!

I

,

,

2

4

I

5

I

I

6

7

e

I

9

OESIGNFACTOR

Figure 60. This graph is called the Rrltllil'c' S",l'ic(' Lifc' CUrI'c'. Ii relates the service life to operating loads, A design factor of 5 is chosen mqs\ frequently,

7(>

BREAKING STRENGmS The breaking strength is the ultimate load registered on a wire rope sample during a tension test. '~;.: The nominalstrengths given (Tables 18 through 36), have been calculated by a standardized, industry-accepted procedure, and manufacturers design wire rope to these strengths. When making design calculations, it should be noted that the given figures are the static strengths. All discussion of strength is predicated on the assumption of there being a gradually applied load less than 1" /minute. Designers should base their calculations on these strengths. A minimum acceptance strength, 21/z % lower than the published nominal breaking strengths, was established as the industry tolerance. It serves to offset testing variables that occur during the actual physical test of a wire rope sample. This tolerance is used in the basic wire rope governmental specifications. Wire rope testirig, whether it is performed for the purpose of determining grade or for adherence to specifications, requires the sample to be tested to meet certain standards: For example: the sample's length must not be less than . 3 ft (0.91 m) between sockets for ropes with diameters of from ys,jnch (3.2 mm) through 3 inches (77 mm); on ropes with larger (over 3 inches) diameters, the clear length must be at least 20 times the rope diameter. The test is considered valid only if failure oCcurs 2 inches (51 mm) Or morefrom either of the·sockets, or from the holding mechanism.

77

,j."

TABLE19 NOMINAL STREN:GTHS OF WIRE ROPE 6 x 7 Classification/Bright (Uncri~!ed), IWRC

Nominal Diameter

Approximate Mass

Nominal Strength* Improved Plow Steel

inches

mm·

Ib/ft

kg/m

;4

6.5 8 9.5 11.5

0.10 0.16 0.23 0.32

0.15 0.24 0.34 0.48

% %

13 14.S· 16 19

0.42 0.53 0.65 0.92

0.63 0.79 0.97 1.37

11.1 14.0 17.1 24.4

10.1 12.7 15.5 22.1

Y8 1 B/s 1;4

22 . 26 29 32

1.27 1.65 2.09 2.57

1.89 2.46 3.11 3.82

33.0 42.7 53.5 65.6

29.9 38.7 48.5 59.5

1% 1;,z

35 38

3.12 3.72

4.64 5.54

78.6 92.7

71.3 84.1

lh6 % ~6

Ih ~G

*To convert to Kilonewtons (kN).multiply tons (nominal . breaking strength) by 8.896; lIb 4.448 newtons (N).

=

i

,

""-..:.;;;/

79

tons 2.84 4.41 6.30 8.52

metric tonnes 2.58 4.0 5.72 7.73

\

"r

TABLE20 NOMINAL STRENGTH~ OF WffiE ROPE 6 x 19 Classification/Bright (Uncoated)~ J.~) ..

OPEN WIRE ROPE SOCKETS (POURED)

TABLE 38 DIMENSIONS (inches)

Rope Diam.

Approx. Wt J

K

L

N

31'4

lYJll

1~11l

~1n

FiSr.

l1Afi

31'4

' 1~11l

1 :~.[t:!

Ph

1'Vs ' 21,4

1:!1r. 1 111'4,

1

liz 'Hli

lYs 2 v..

10/1r. ,1 1:1111

1 Y2, 1% 2 2%

% % 'Vs 1

2% 3 1/s 3% 4 1/s

2 31'4

B

C

D

E

G

2 2

1~11l 1%

31'4

4~Y11l

2

40/s 5°·1'u

1~"H 1!Jt,t;

2Y2 3

'Vs ,i 1"n

2Y2

IJ,4

6 31'4

3Y2 4 ':".;,;r.'/.' 4 liz 5

3 3 1/2 4 4 liz

. 11111 1%

5 1/2 6 6 1/2 711z

5 6 6 1/2 7

8 112 9 9 3,4 11

9 10 10 31'4 11

12 13 14 15

1 JI,4 1 B~ 121/2 13Y2

A

P

Lb ,

%;& 14' ~}SG & 3/8 'Vlr.& liz 1)10 & s/s % 'Vs 1 1V8 11,4&1% 11/2, ,1% 1%&I'Vs 2 2 1,4 21/2 2 31'4

& 21/8 & 2 318 & 2% & 2'Vs

3 & 31/8 3 1,4 & 3% 31/2 &3~1l 3%-4

71~"H

' 2~1U

9 1,4 10u'i,i

2'~]li

Ill::,!,;

2% 3%' 3% 4

211.1,; 31/8' 3 1,4 3%

13:);1n 15Ys 16 1,4 18 1,4

4% 5% 5 112 6%

4

211/2 23 112 2'5 Vi' 27 1,4

7% 8 1,4 91,4 10 31'4

41,4 4 3/s

29 30% 33 1,4 36 11.1

11 1/2 12 1'4 13 14 1/.i

4 112 :; 5 1,4 5:}4 6 J/M ':6~4

7% 'i{;';

1%,0 P/s IJ,4 , 1112

PA

2 11'4

1ilti l!J.1°tj

4 31'4 5% 5% 6 112

2Y2 2% 3 3 112

32.0 ;47:0 55.0 85.0

4 4 1/2 5 5 11'4

11:1111 .21/8 2% 2'Vs

7 7%" 81/2 9

3% 4 1,4 4 3,4 5

125.0 165.0 252.0 315.0

53..4 6 1/4 M4 71/2

3 31/8 31,4 3lj2

91/2 10 103,4

5 1,4

380.0 434.0 563.0 783.0

2

2 11'4 23,4 3 31/lj

2Y2 3 3 31/2

1 1/8

4'Vs

33..4 4 4 1/2 4Y8

5 I;~ 53,4 6 1,4 7

5 1,4 53,4' 61/2 7 1,4

4~i;

0.9 1.1 2.3 3.8

,6.0 10.0 15.0 23.0

Ph 13..4

1% 2

3 31,4 3Ys

.}

2.J,4

1:t1li

12~'2

1% 1% 2

51/2 6 7

'NOTE: DifuensidJisatefot,reference6rtly. Consult your supplier of the specific fittings for exact details.

lID

OPEN SWAGED WIRE ROPE SOCKETS

TABLE 39 DIMENSIONS (inches) (after swaging)

Rope diam.

After, Swaging A

B

Jaw opening C

Pin diam. D

E

F

W

~6

%

1~6

l~G

Ph

1~16

~'16

1~6

. Hj'b

10/16 10/16

10/16 10/16 1

1%

10/16

2

H1G 1% 1%

%

1~6

Ylfl

%

1%2 %6

1/2 % % 'Vs

%

%6

lYs

,1%2

1%

2~2

lY2

%

13.4

%

2 2w 2 112

1 P/s P/s

2% 3

H16 ,,1%6 161;(;4

1 ·1% H~

1% B-2 1% 2

3~

1 1 lw, 1 1/2 1% 2 2w 2~

2 2'IA 2 112 2 112

3

2~~

3 112

3 112

4

3%

2~

H

L 4

P/s

1% 1% 1% 2

2 2w 2% 3 1/:'

1Ys 1% 1%6

2 2% 2%

6 11/16

12ry{{2

3~/s

3 3,4 4w

4~6

4~

2%2 2')16 2g'16

4 1h

5 lA

21~1t,

5

5% 6% 8

3Ys

5 112

3% 4%6

6w 8

13,4

19,j(j

31~6

5~16

5%6 61~6

Approx. wt/lb .52 1.12 1.07 2.08

10 llVs

2.08 4.28 7.97 11.3

13% 15 16 112 18 1/s

17.8 26.0 34.9 44.4

19% 23 26%

58.0 87.5 150

8Ys

NOTE: Dimensions are for reference only. Consult your supplier of the specific fittings for exact details.

II I

OPEN SWAGED STRAND SOCKETS

TABLE 40 DIMENSIONS FOR 19~WIRE AND 37·WIRE STRAND (inches) (after swaging)

r·

~

i, .. jJ;

',c\;,.

Fj-l

L@=r

k

Strand diam;

A

1,4&%6 % 1716 & % 1710 & %

l1/s 1% 11,4 P/.;

1%6 & 1 1710 &1 1/8 1710 & 11;4 1%6 & 1%

2 21;4 2,1/2

2 3/.;

Pin diarn. D

Jaw opening C

B 5/S

% 1~16

1132 1~6 1~6

Hio

mu.

B

---r

c

-L

Approx. wt/1b without Pin

E

F

H

L

1~0

2 112 3 3% 4

83/.; 10 1/2 121;4 14

3.5 6.25 9.25 14.5

2!)1n

4112 5 51/.; 5.%

15 3/.;

20.5 29.25 38.25 45.0

11;4 1112 . 1% 2

1716 Ph 1% 2

21;4 2% 3 1/.; 3%

21;4 21,4 21h 3

21;4 21h 2 112 2%

4 1/.; 4% 51;4 5%

11710 2 2%

21~ln

3Vs 31h

17V2

191;4 21

NOTE: Dimensions are for reference only. Consult your supplier of the specific fittings for exact details. :

.," '

112

"

~

(.

..

__ ...

---'---~

/~,

CLOSED SWAGED WIRE ROPE SOCKETS

TABLE 41 DIMENSIONS (inches) (after swaging)

t

~--;--.L.......r----J._~P"--,_j After Eye Rope Swaging thickness diam. A B '/.4 0/16 % i-5.6

1h 40/64 40/64 50/64

1% 1% . 1% 2

\ C§(!

Hole diam. D

E

% % Ys

1% 10/16 10/16

Fh6

(lb)

1~:16

31/2 41/2 4Y2. 5%

.32 .77 .72 1.42

5 3;.4 7 1/4 8% lOlls

1.35 2.85 4.90 7.28

1%6 1~16

P/2

1ij-:12

Ph 11%6 2 1/4 2 1YJ.6

Bob

1 Iva 1'/.4 1%

1% 2 2 1,4 2Y2.

1% 2 .2'/.4 .2'/.4

3% 4. 4Y2. 5

27:1(; 2%G 2%G 2716

3 30/16 3% 47:16

2~1.6

Ph 1% 2

2% 3 3 1h

2 1h 3 3'/.4

51/2 6'/.4 7%

21~:1G

4JA 5va 6

2 B:1f1 2% 1'/.4 2% 1i-5.G 3va . P7:16

3!j16 310/1\l

r-E-+-F-l [ i :i n

L

% Ys

50/64

!

F

lVs 1%6 l1/2

§-E.

I

Approx. wt

Ys 1% 1% Ph

1/2

113

i-5.6 17:16 17:16 Ys

C

.'.....f - - - - L

1% 1~%~ 11~lG

20/16 2"Vs

11 1h 12% 14% 15%

10.3 14.4 21.4 27.9

3va 3!YJ.r, 4%

17 20 23

36.0 51.0 90.0

2%~

CLOSED SWAGED STRAND SOCKETS

TABLE 42 DIMENSIONS FOR 19·WffiE AND 37·WIRE STRAND (inches) (after swaging)

Strand diam.

A

1/2 & ~o % 11Ao & 34 l:}lo & %

}I/s 1% 11h

11~ ..

2 2% 2 112 2%

& 1 IIA.. & 11/s l=})o & 1% l ril.. & 1%

}3;4

Eye thickness B

C

}I/s mo I1h 1%

21h 3 3th 4

114

2

4Y2

211h~

214

5 5% 5th

2% 2th

Hole diam. D

II~b 12%~

2:1112

Approx. wt E

2Ys 2% 3 1;8 3%

2 1%2

3 3;4 4 14

21%~

4 112

2%

4%

F l~fI

1% 2 2 14 2Y2

2% 31/s 3%

L

(lb)

7 112 9 11 12Y2

2.75 5.0 7.25 11.0

13 112 15 161/2 18

16.0 23.0 29.0 35.5

NOTE: Dimensions are for reference only. Consult your supplier of the specific fittings for exact details.

114

\-.

OPEN SWAGED SOCKETS

TABLE43 DIMENSIONS OF SOCKETS (inches) OPEN WIRE ROPE WEDGE·TYPE SOCKETS These wedge-type sockets are easily and quickly attached in the field by bending the rope end around the tapered wedge. This type of socket is normally furnished without pins.

f-B~

Diameter' of rope

..,

A

Center of pin hole to end' of socket A

Opening between ears B

Diameter of pin hole C

¥!l

5~

sh

1~6

~

5Vz

1~6

%', %

7 7 1/2

% 1¥!l 1%

'Va ·1

, I1h'

1% 1% 1~

1%

9 9% 10% 11% 11% 13 1,4 13%

13,4

1% 1%

~'''i,

]

Approximate wt (lb)

2.5 2.5 5 9

1% 1% 1% 21h

15 20 23 32

2~

2Y8 3Y8

2~

31h

32 52 52

ISh '1~

13,4 1%

NOTE: Dimensions are for reference only. Consult your supplier of the specific fittings for exact details.

115

a

.. (."

WIRE ROPE ASSEMBLIES When ordering wire rope ;"'ith fittings attached. lengths-as shown-should be specified. Additionally, the load at which this measurement is taken should be specified, i.e., at no load, at a percentage of catalog breaking strength etc. The accompanying drawings do not show all possible combinations of fittings; in any case, the same measuring methods should be followed.'

Zinc-attached closed wire rope socket at (Jne end; zihc;.attached open wire rbpi socket at other end. ,:.~ Measurement: Pull of closed socket to centerline of open socket pin.

b

Closed swaged wire rope socket at one end; open swaged wire rope socket at other end. Measurement: Centerline of.,pin to centerline of pin.

c

Closed bridge socket attached to one end; open bridge socket attached to other end. Measurements: Centerline of closed socket pin to centerline of open socket pin; include two of the three values: takeup, contraction, and expansion. The values of C and 0 are also required.

d

Thimble spliced at one end. Measurement: Pull of thimble to end of rope.

e

Link'spliced atone end,' hook spliced at other end. Measurement: Pull of link to pull of hook.

f I)

Thimble spliced at one end; loop spliced at other end. Measurements: Pull of thimble to base of loop, and circumference of loop.

116

\..

.

'.;.

a

b

~

1Y::0f&{?ik~~",,;Z-~: ;~·;:~·~ s~-0"' :; ;'-'"' '>,-c.; =*", -~", "*. .~""'~""'""'."""""";.;S:;,,"",,","';::,"",~""~,",:,",,["-II---@ ,-I!

- - - - - - - - - - - - - - - - - L E N G T H - - - - - - - - - - - - - - - - - -......

I -. !.

c

""""'11"''''''' "~ HTAKE UP

--+-------mm-rm~~~'=::k;J~:::::::::: ~ ~ i

J------------------LENGTHI------------------_ .. ' TAKE UP, ICONTRACT10N)+ (EXPANSION)

d

e

117

,:'.'

BOOM PENDANTS WITH SWAGED FITTINGS

I

SINGLE-ROPE LEGS AND OPEN SWAGED SOCKETS

',~

I , .