WIRE ROPE SLINGSINDEX-INTRODUCTION WIRE ROPE SLINGS -FACTORS CAUSING ROPE DETERIORATION-PARTS Normal wear (and tear)-Broken wires-COMPOSITION-LAY Corrosion-PRE-FORMING Abrasion-PARALLEL/CROSS LAY Mechanical Damage-CORE-ROPE CONSTRUCTION Thermal damage (overheating)-CLASIFICATION Malformations-DESCRIPTION/DESIGNATION Rotation-CROSS SECTIONS-GRADES & FINISH OF WIRE Fatigue-FACTOR OF SAFETY Termination failures-CERTIFICATES -WHERE TO EXAMINE-CRITICAL AREAS-MARKING-COLOUR CODE -EXAMINATION OF ROPES THROUGH SHEAVE-MEASUREMENT -INTERNAL EXAMINATION AND AT ROPE-CHARTS TERMINATION OF ROPES-PARTS -DISCARD CRITERIA WIRE ROPE SLING-TYPES -MAINTENACE-EXTREMITY AND LOOPS ACCESORIES -STORAGE/HOUSKEEPING-INSPECTIONS -SAFE USE (WIRE ROPES SLING/HOOK/ WEDGE-PRE-USE INSPECTION SOCKET-DAMAGE -TEST
WIRE ROPE SLINGS-INTRODUCTIONLearn the basic of wire rope, including the nomenclature, how it isconstructed, and how diameter and lay measurements are made.How to choose the right ropes for your needs, how to extend rope servicelife, the importance inspection, and how to properly store and handle wirerope. For: Types: – Strong – Single leg, two, three or four leg – Flexible – Wide range available – Single part or double part – Resists most chemicals – Hard eyes or soft eyes – Resist heat – With or without fittings Against – 5:1 factor of safety – Non adjustable – Could damage the load
WIRE ROPE SLING-PARTSGenerally speaking, all ropes nowadays are preformed in manufacture.This is a process where wires and strands are pre-shaped to a helix shape.There are a great many different rope constructions, each one having its ownparticular use.There are three main things to observe when examining the constructionof wire rope: CENTER WIRE/ KING WIRE •Number of wires in each strand •Number of strands in the rope •Direction in which wires and strands STRAND •Lay (spiral) in the ropeCOREThe core of a wire rope can be: CORE •Fibre (FC) •Wire Strand Core (WSC) •Independent Wire Rope Core (IWRC)STRANDS WIRE ROPEDepend on classification of rope but usually consists of wiresspiralling around a central core wire.
WIRE ROPE SLING-PARTS Used to hoist materials Selection considerations: WIR E strength ability to bend without cracking ability to withstand abrasive wear ability to withstand abuse ROPE STRAND Outer wire Centre wire Inner wire Outer wire Centre wire Inner wire Core wires
WIRE ROPE SLING- LAYREGULAR / ORDINARY LAY (HO) RIGHT LAY RHO ORDINARY LAY -sZ LHO LEFT LAY ORDINARY LAY -zS6 and 8 Stranded LANGS LAY (HL) RIGHT LAY RHL LANG‟S LAY -zZ LEFT LAY LHL LANG‟S LAY -sS MULTI-STRANDED ROPE Alternate RIGHT LAY REVERSE LAY (CROSS LAY) Lay (AZ or AS)Outer- Right hand Right (Z-R)Inner- Left hand Left (S-L)
WIRE ROPE SLING- LAYREGULAR / ORDINARY LAY LANG LAY In this construction, wires and strands spiral in theIn this construction, the wires and strands spiral in same direction.opposite directions. Right-hand lay is usual, but it can be supplied in left-hand lay:In right-hand ordinary lay, the wires spiral to the leftand the strands to the right. 6 and 8 stranded Langs lay rope has better wearingIn left-hand ordinary lay, the wires spiral to the right properties than ordinary lay, but it is harder to handle. and the strands to the left. Both ends must be secured to prevent twisting or the load has to be guided (i.e. not free to rotate). NotThese ropes are easily handled, and can be used with normally used for slingsone end left free to rotate, but they wear quickly Has better wear resistance when running overbecause only a few crown wires are in contact with the sheaves because a longer part of the wires is inbearing surfaces at any one time. contac with the sheave.
WIRE ROPE SLING- LAYMulti-Stranded RopeBoth Langs lay and regular/ordinary lay are used, with a double-layer (or triple layer)construction.If the inner rope is left-handed , then the outer covering will be right-handed , or vice versa.Occasionally used for crane pennants.It is a rotation-resistant rope- has a steel core which is an independent rope, closed in theopposite direction to the outer strands. Under load the core tries to twist the rope in the onedirection, the outer strands try to twist it in the opposite direction. The moments in the core andthe outer strands compensate each other. over a wide load-spectrum, so that even with greatlifting heights no rope twist occursMulti Strand ropeOuter- Right handInner- Left hand
WIRE ROPE SLING- PRE-FORMINGIn a pre-formed wire rope during the closing stage the strands are given Pre-formeda helical shape. This process reduces almost completely the tendency ofthe rope to unravel and reduces the elastic stress in the wires formingthe strands.This process has a few advantages:• Reducing the stresses in the wires improves their fatigue resistance and extends the service life of the rope.• Broken wires dont tend to protrude. In every rope some wires break during use due to fatigue or wear. In non-preformed ropes, Non- these tend to protrude from the rope. This may cause damage to preformed adjacent strands and cause injuries during maintenance.• Preventing unraveling of the cut ends. When a non-preformed wire rope is cut, the end tends to unravel. Seizing is still necessary at the end to ensure that it will not unravel if it is hit by something but one seizing is enough. See additional information in the Storage, handling, installation and maintenance section.
WIRE ROPE SLING-PARALLEL/CROSS LAY Cross lay or point contact lay – Parallel/Equal Lay All wires have different lengths, and All strands have different lay lengths (Core and outer were laid independently in separate work proceses) Hig stress concentration at the crossover point leads to an early internal failure Parallel lay – All wires have the same lay length and All strands have the same lay length Cross Lay (These strands are manufactured in one operation.) Linear contact leads to an optimal stress distribution Parallel lay has the advantage that the contact between layers is along a line, not in a few points, resulting in a larger contact area which reduces the stresses and improves the ropes resistance to fatigue and radial stresses. Cross lay- Better able to tolerate the more casual rope handling techiques-multiple bends. Parallel lay - Better high breaking stregth and favorable fatigue bending characteristics But can be susceptibles to untwisting.
WIRE ROPE SLING-CORE WSCCORE- (ISO 17893)FC-Fibre - Should not be used at temperatures of more than 100ºCNFC-Natural Fiber CoreSFC-Synthetic Fiber Core IWRCWC-Steel core- Can work at temperatures up to 250ºCWSC-Wire Strand CoreWRC-Wire Rope CoreIWRC-Independent Wire Rope CoreIWRC (K)-Independient wire rope core with compacted strand PWRCEPIWRC-Independient Wire Rope Core covered with a polymerEFWRC-Wire Rope Core Enveloped with FibreESWRC-Wire Roper Core Enveloped with Solid polymerPWRC- Parallel Wire Roper CorePWRC(K)-Parallel Wire Rope Core with compacted strandsKWSC- Compacted Wires Strand Centre ESWRC
WIRE ROPE SLING-ROPE CONSTRUCTIONThere are many different rope constructions, each with its different properties,advantages and disadvantages.Stranded ropes are divided to two main groups: Single layer ropes – these ropes have only one layer of strands, normally 6 or 8 but in some special constructions even as low as 3 strands laid helically around a core. Some 3 or 4 stranded rope constructions do not have a core at all. Multiple layer ropes (rotation resistant ropes) – these ropes have at least two layers of strands laid helically around a core which is normally WSC. The direction of lay of the outer layer is opposite to the underlying layer. Under load the torque developed by the outer layer is counteracted by the torque of the inner layers to reduce the overall torque and rotation of the rope. Rope constructions with more layers have better torque balance.Rope constructions are further divided into classes according to the number ofwires in the strands. For example: a rope of class 6x19 may actually be 6x26Warrington Seale. Ropes with different constructions within the same class havesimilar properties.
WIRE ROPE BASICS-CLASIFICATIONNumber of strands and construction determine wire rope classificationSINGLE LAYER- the most common example of thes single layer construction is a 7 wirestrand. It has a single-wire center with six wires of the same diameter around itSEALE- has two layers of wires around a center wire with the same number of wires in eachlayer, and all wires in each layer are the same diameter.The strand is designed so that thelarger outer wires rest in the valleys between the smaller inner wires.FILLER WIRE- has two layer of uniform-size wire around a center wire with the inner layerhaving half the number of wires as the outer layer. Small filler wires, equal in number to theinner layer, are laid in valleys of the inner layer.WARRINGTON- has two layer with one diameter of wire in the inner layer, and two diametersof the wire alternating large and small in the outer layer. Ther large outer-layer wire rest in thtevalleys, an teh smaller ones on the crownsm of the inner layer.COMBINED PATTERNS- is formed in a single operation using two or more of the differentconstructions.Characteristics like fatigue resistance and resitance to abrasion are directly affected by thedesign of strands.
DESCRIPTION/DESIGNATIONThis term refers to the number of strands that form the rope, number of wires ineach strand, the arrangement of the wires in the strands and the arrangement ofstrands in the rope. In general ropes constructions are designated by two groups ofdigits separated by a multiplication sign “x".The first group is the number of strands in the rope.The second group is the number of wires in the strands,The second group may have additional prefix and/or suffix letters- type of core 18 x 7-WSC= is a wire rope composed of 18 strands of 7 wires each. Wire Strand Core (WSC)Example of Rope Description/Designation 22mm dia. 6x36 IWRC 1960 Ung RHO 22mm dia= Size (nominal diameter) 6x36 = Rope Construction- 6 Strands of 36 wires each IWRC= Core Type 1960= Rope Grade Ung = Ungalvanised (bright) RHO= Direction and Type of Lay (Right Hand Ordinary Lay)
DESCRIPTION/DESIGNATIONExamples of Rotation Resistant Ropes Class No. of Strands No. of No.of layers No. of wires excluding centre outer strands of strands in outer strand strand Examples of Single Layer 17-18 2 5-9 Stranded Ropes 18x7 10-12 18x19 17-18 10-12 2 15-26 8x7 3x7 6x7 3x19 6x19 8x1934(M)x7 34-36 17-18 3 5-9 3x36 6x36 8x36 5-9 6x61 8x61 35(W)x7 27-40 15-18 335(W)x19 27-40 15-18 3 15-26 4x735(W)x36 27-40 15-18 3 29-57 6x8TS 7-26 4x19 6x19M 35LS 34 16 3 4x36 6x24M 6x25TSParagon 15 12 2 6 6x37M Examples of Parallel Closed Ropes 5x5 Class No. of Strands No. of No.of layers No. of wires 5x7 7x19 excluding centre outer strands of strands in outer strand strand 7x36 8x7 16 8 2 5-9 8x19 16 8 2 15-26 8x36 16 8 2 29-57 DSC 8 16 8 2 7-36
WIRE ROPE -Cross sections Examples of “Single Layer”-6 Strand Ropes Examples of “Single Layer”- 8 Strand Ropes
WIRE ROPE -Cross sectionsExamples of Stranded Ropes with Example of a Triangular Strand Plastic Cushion Core/Centre Solid Polymer Filled Rope Construction 25TS Typical rope constructions: 6x25TS - FC Flat Ribbon Strand Construction Typical Example Compacted Round Strand Construction 6/0 Before compacting After compacting Typical rope construction: 12x6/3x24 (Paragon) Example is 17S(8/8/1)
WIRE ROPE -Cross sections WIRES IN A SPIRAL ROPE Spiral Strand Full Locked Coil Half Locked Coil Typical Example Typical Example Typical rope constructions:1x108 or 33/27/21/15/9/3 24FL/20FL/12/6/1 9H+9/12/6/1 Future European primary designation: Z2 - 19W Future European Secondary designation: 24Z:20Z:12/6/1
WIRE ROPE SLING Stranded Rope-Round strand construction Typical rope constructions: Single lay strand 6x36WS - FC 7(6/1) 6x36WS - IWRC Typical rope 6x41WS - IWRC constructions: 8x36WS - IWRC 6x7 - FC Combined 6x7 - WSC parallel lay 36WS(14/7+7/7/1) 41WS(16/8+8/8/1) Seale construction Filler construction Warrington construction(parallel lay/equal lay) (parallel lay/equal lay) (parallel lay/equal lay) 19S(9/9/1) 25F(12/6+6/1) 19W(6+6/6/1) Typical rope constructions: Typical rope Typical rope constructions: constructions: 6x19S - FC 6x19S - IWRC 6x25F - FC 6x19W - FC 8x19S - FC 6x25F - IWRC 6x19W - IWRC 8x25F - FC 8x19W - FC 8x19S - IWRC 8x25F - IWRC 8x19W - IWRC Multi-operation lay strand Cross Lay(M) Compound Typical rope Lay(N) constructions: 6x19M - FC 6x19M – WSC 6x35NW - FC
GRADES OF WIRE ROPE & FINISH OF WIREGRADES OF WIRE ROPEWire rope manufacturers have many different grades to meet the varying demand for strength andtoughness. Tensile strength is the wire rope‟s resistance to breaking under tension. Higher tensilestrength in a wire rope means that it‟s ability to be drawn out or stretched changes with differentgrades of steelTensile Strength Identifies the level of minimum breaking force (KN) or minimum breaking load (t)Grades of wire rope arePlow Steel -1570 Grade------Tensile strength of 1570 N/mm2=160 kp/mm2Plow Steel wire rope is unusually tough and strong.Improved Plow Steel (IPS)-1770 Grade- Tensile strength of 1770 N/mm2=180 kp/mm2Improved Plow Steel wire rope is one of the best grades of rope available, and is the mostcommonly used rope. Improved plow steel is stronger, tougher, and more resistant to wear than plowsteel.Extra Improved Plow Steel(XIP/EIPS)-1960 Grade- Tensile strength of 1960 N/mm2=200 kp/mm2for special installations, where maximum rope strength is required, and conditions of use permitsome applications such as mine shaft hoisting, where increased tonnages on existing skips anddrums can be tolerated, and where conditions such as sheave and drum diameters are favorable.Extra Extra Improved Plow Steel Grade (XXIP)-2160 N/mm2 = 220 kp/mm2FINISH OF FIREThe surface of these wires is bright , drawn galvanized or heavily galvanized, or stainless steelwire.Bright-ropes made with uncoated (bright) wireGalvanized- to improve corrosion resistance (zinc coated )Stainless steel wire- special alloy aprox 18% chromium and 8% nickel, high resistiance to many corrosiveconditions.
FACTOR OF SAFETYA FACTOR OF SAFETY is applied to all wire ropes industry wide.When the manufacturer makes a new wire rope, they remove a samplepiece and test it to destruction.When the sample piece breaks, we refer to this as MINIMUM BREAKINGLOAD (M.B.L).The MINIMUM BREAKING LOAD (MBL) is then divided by the FACTOROF SAFETY (FoS) relevant to the ropes intended application to achieve aSAFE WORKING LOAD (SWL). FoS= MBL ÷ SWL SWL = MBL ÷ FoS WLL= BREAKING STRENGTH/ DESIGN FACTOR MINIMUM BREAKING LOAD = MBL SAFE WORKING LOAD = SWL FACTOR OF SAFETY = FoS SAFE WORKING LOAD NEVER CAN BE OVERRANGE/OVERLOADED
FACTOR OF SAFETY FoS = MBL/SWLSTANDING ROPES (PENDANTS) 3.5:1RUNNING ROPES 5:1GENERAL PURPOSE WIRE SLINGS 5:1WIRE ROPES FOR LIFTING PERSONEL 10:1 SAFE WORKING LOAD SPECIFIED BREAKING STRENGH SAFETY FACTOR
CERTIFICATES CERTIFICATE OF TEST OF WIRE ROPEEmployers should hold the Test Certificate Numbersling Certificate of Purchaser Name and Address Tel: Supplier Name and Address Tel: Fax: Fax:Conformity and where Purchase Order Noproduced a Test Certificate Sales Order Number DESCRIPTION OF WIRE ROPE 12 mm 8x19(S)FC 1370/1770 BT RHO ZL010005 MBL 6.45t- not only because the law ________________________________________________________________ ______ Rope Number Z45186Aso demands - but because Quantity and Rope Length Date of Manufacture 1 x 2800 (m) 05/08/96it may be vital evidence in DETAILS OF TEST Method of Test IS0 3108the event of a failure of Date of Test Breaking Load 05/08/96 > 6.45 (t) Safe Working Loadequipment while in service. at a Coefficient of Utilisation of 5 * 1.29 (t) DECLARATION I certify on behalf of the firm or persons named above that theThe certificate is above particulars are correct. Name J Bloggs Signed J Bloggsdocumentary evidence of Date 26/08/96 __________________________________________________________ __________________________________the legal SWL of the sling. OTHER INFORMATION Testing Machine Calibrated to BS EN 10002-2 Product Code : 12.00819AF11RA Example Test Test Cert * If the rope is to be used at a coefficient of utilisation different from the example above, it should be re-rated by a competent person.
MINIMUM REQUIREMENT FORMARKING OF LIFTING EQUIPMENT Safe Working Load (SWL/WLL) Unique Identity Number/Reference- Serial number Date of inspection or Colour code
WIRE ROPE SLING MARKING SLING IDENTITY IDENTIFICATION No.INSPECTION COLOUR CODE SAFE WORKING LOAD INSPECTION SWL 0O to 90O COLOUR CODE FERRULE SERIAL NUMBER DATE MANUFACTURE / LOAD TEST SWL (safe working load) WLL (work load limit) EYE WITH THIMBLE COLOUR CODED COLOUR CODE COLOUR CODE SLING MARKING
MEASUREMENT OF ROPE DIAMETER ROPE DIMENSIONS 2 measurements at right angles at two positions spaced approximately one metre apart. (Measurements taken over strand crowns) Average of the four measurements is the rope diameter.
PARTS WIRE ROPE SLING Master linkIntermediate links tag SlingsHooks/Shackles/Eye with Thimble/Soft Eye
PARTS WIRE ROPE SLINGTerminations being formed by mechanical splicing commonly known as talurits orferrules.The eyes of the sling can be fitted with or without thimbles according to its purpose.For general use , soft eye superloop slings are preferred, the eyes of which areconstructed by splicing the wire and pressing on a steel ferrule to secure the splice,also known as Flemish eyes.Transit slings are manufactured using standard talurit fittings. FLEMMISH EYE ALUMINIUM HARD EYE LOOP BACK SUPERLOOP or FLEMISH EYE SLINGS With a Flemish eye (Superloop) wire rope termination, there is no tail due to the wire being spliced and ALUMINIUM SOFT EYE terminated within the ferrule. LOOP BACK
EXTREMITY AND LOOPS ACCESORIES WIRE ROPE SLINGSLocation of the locking clamps The length (h) of the loop on asteel wire rope must be at least 15 times the rope diameter(d) when ferrules are used, 10 times in case of hand splicing.The distance between the two ferrules on lifting slings mustnot be less than 10 times the rope diameter (d).The same restriction applies to splicing.The measurement is taken from the point of each clampnearest the other.
WIRE ROPE SLING INSPECTIONInitial inspection:• Prior to use, slings shall be inspected by a Competent• Person.Frequent inspection:• Visual inspection, not recorded, by user or designated• person. Regular inspection while in use.Periodic inspection:• Visual inspection recorded, by Competent Person at defined periodic basis.EACH DAY BEFORE USEWHERE SERVICE CONDITION WARRANT • SWL/WLL • Expire Date • Color codeREMOVE THEM FROM SERVICE IF DAMAGE ORDEFECTIVE
WIRE ROPE-PRE-USE INSPECTIONPre-Use Examination Ensure the sling has an I.D. number the SWL is adequate. Examine each individual leg along its entire length and check for wear, corrosion, abrasion, mechanical damage and broken wires. Examine each ferrule and ensure the correct size of ferrule has been fitted. Check that the end of the loop does not terminate inside the ferrule. The ferrule should be free from cracks or other deformities. Examine each thimble and check for correct fitting, snagging damage and elongation. (stretched thimbles/eyes could indicate possible overload). Examine wire rope around thimbles as it is often abraded due to sling being dragged over rough surfaces. If fitted, examine master link/quadruple assembly and check for wear, corrosion and cracking. If fitted with hooks, check for wear, corrosion and cracking and ensure safety latch is working correctlyINSPECTION CRITICAL POINTS There are certain points along any given rope that should receive more attention than others, since some areas will usually be subjected to greater internal stresses or to greater external forces and hazards. Carefully select the most critical points for close inspection - points where failure would be most likely to occur. The same critical points on each installation should be compared at each succeeding inspection.
WIRE ROPE DAMAGEBroken wires in the valleys (sometimes calles gussets or Broken wires on the crowns of the strand of the rope interstices) between the outer strands of the rope External corrosions Close up of external corrosion Local increase in rope diameter due core protrusion Basket deformations Kink Kink Core protrusion
FACTORS CAUSING ROPE DETERIORATION NORMAL WEAR AND TEARBROKEN WIRESUsually caused by mechanical damage or corrosion. Theyreduce the strength or the rope and can cause hand injury tothe user.Sling must be rejected and replaced if any strands are totallybroken, wire breaks occur very close to each other or thenumber of wire breaks exceeds 5% of the total number of wiresalong a length equal to six times the diameter of the rope.Or the nominal diameter of the rope has worn more than 10%in any point
FACTORS CAUSING ROPE DETERIORATION CORROSION Areas of Wear in a Rope CROWN WEAR STRAND INTER CORE STRAND WEAR/ WEAR/ MARKING MARKING (INTERNAL) (INTERNAL)This causes loss of flexibility and roughness to the touch.Withdraw the sling and refer to supervision if necessary.Wire rope corrosion is caused by: External Can normally be seen Poor storage and assessed Exposure to the weather/elements Exposure to corrosive chemicalsIt is recognised by: Internal Discolouration Cannot be seen without opening Lack of flexibility ropes up. More difficult to assess Roughness to the toughCan be a major cause of deterioration
FACTORS CAUSING ROPE DETERIORATION CORROSIONEXTERNAL WEAR INTERNAL WEAR*Normal wear on strand crowns – Affected by pressure / frictionreasonably easy to see and assess* – Level of rope tension• Affected by the Appliance / Machine / Duty – Bending ratio – Rope Tension – Frequency of bending – Size of drum / sheave – Lack of lubricant – Number of sheaves – Degree of tension - tension fatigue – Condition of drum / sheave(s) *Unable to see without opening rope up* – Rate of acceleration / deceleration – Momentum of sheave(s) – Fleet angle – Spooling arrangement at drum• Affected by environmental conditions – Abrasive dust – Lack of lubricant / dressing in service
FACTORS CAUSING ROPE DETERIORATION ABRASION• Normal - expected due to rope duty – e.g. drag rope on dragline; trawl warp• Abnormal - unexpected – e. g. contact with adjacent structure; seized sheave/pulley/roller/fairlead; undersized sheaves/pulleys; misaligned sheaves/pulleys – Abnormal abrasion Heat generated Possibility of martensite being formedAs shown, the majority of abrasion damage is caused by unnecessary chaffingaction against the deck / ground, load or adjacent objects Contact with adjacent structure Dragging from under a load Double choke hitching
FACTORS CAUSING ROPE DETERIORATION MECHANICAL DAMAGE• During storage/handling• During installation - kinks & bends• Damage from vehicles• Rope jumping out of sheave• Rope trapped• Incorrectly profiled sheave grooves• Poor spooling at drumWhat is the most common reason for Discard?
FACTORS CAUSING ROPE DETERIORATION THERMAL DAMAGE• Too high operating temperature - loss in strength• Electric arcing during welding - localised damage• Lightening
FACTORS CAUSING ROPE DETERIORATION MALFORMATIONS• Resulting From: – Poor installation technique – Shock loading – Unacceptable fleet angle - causing rolling of rope – Lack of maintenance (equipment and/or rope) Example of result of shock loading
FACTORS CAUSING ROPE DETERIORATION ROTATION• Incorrect handling/installation techniques• Incorrect use of swivel• Wrong rope for job Example of „birdcage‟ due to torsional imbalance
FACTORS CAUSING ROPE DETERIORATION FATIGUE • Bending fatigue • Tension - tension fatigue • Torsional fatigue Resulting in Broken Wires Examples of Broken Wires Due to Fatigue
FACTORS CAUSING ROPE DETERIORATION TERMINATION FAILURESEND ATTACHMENTSAll end attachments have one characteristic in common,,they all restrict to some degree the freemovement of wires at the end of the rope.This impairment of the ability of wires to adjust and move at the end can ultimately result inbreakage of wires at the point where restriction occurs, thus broken wires are a primary concernwhen inspecting end attachments on a rope.A single broken wire is usually reason to question continued use of the rope and more than oneis usually sufficient cause for rejection.Broken wires may be more difficult to locate at end fittings than in other sections of rope.Another problem frequently encountered at end fittings is corrosion or rust.Such corrosion can easily conceal broken wires, and if left to accumulate can erode the surface ofwires to weaken them, or can restrict normal wire movement.Inspection of rope ends should also include the condition of the actual attachment - worn eyes,missing thimbles, bent or opened hooks, pins, etc.End termination‟s to some degree restrict the available movement of the wire rope at theattachment point.This inevitably can cause the breakage of wires where the restriction is occurs.Therefore it is important to ensure that a close inspection of the end termination is carried outprior to use.A single broken wire within close proximity to the termination is generally enough cause toquestion continued use of the wire rope and more then one sufficient cause for rejection.
FACTORS CAUSING ROPE DETERIORATION TERMINATION FAILURESRope Terminations•Spliced eye Failure may occur at the base•Ferrule-secured eye of the swaged•Metal or Resin filled socket fitting in this area•Wedge socket HAND SPLICE•Pressed/Swaged failure may occur•Wire rope grips Check that the thimble is not at the first tuck splice biting into theTermination Failures rope•Incorrect selection of termination•Incorrect fitting of termination Look for wear in•Inadequate inspection/examination the crown•Failure to maintain in serviceWhat to look for at a rope termination (CHECK): Wire breaks Inspect termination, ensure wire rope end is visible. Corrosion Dead end must be flush or Reduction in rope diameter protruding Unusual rope movement Evidence of rope end Evidence of any incorrect fitting Dead end tail = Rope dia. (+/-) Evidence of any component wear Broken wire near fitting. Presence of any interwire pressure/friction marks This is a serious defect ! State of internal lubrication
FACTORS CAUSING ROPE DETERIORATION TERMINATION FAILURESEND TERMINATION DAMAGEEnd termination‟s to some degree restrict the available movement of the wirerope at the attachment point.This inevitably can cause the breakage of wires where the restriction isoccurs.Therefore it is important to ensure that a close inspection of the endtermination is carried out prior to use.A single broken wire within close proximity to the termination is generallyenough cause to question continued use of the wire rope and more then onesufficient cause for rejection. Examples of possible termination failures
WHERE TO EXAMINE-CRITICAL AREASTypical but not exhaustive list: Sheave• Points of attachment - outboard and inboard• Rope at compensating sheave(s)• Dead laps and cross-over points at drum• Rope running through sheave(s) Drum• Rope spooling on/off drum Terminations• Areas exposed to abnormal environmental conditions• Areas subject to damage or likely to be damaged Sheave BlockPrincipal modes of deterioration- At drum 10 t• At drum anchorage-corrosion/evidence of rope movement, (e.g. slip)• Portion entering and exiting drum -corrosion/wear/broken wires• In dead wraps -corrosion/localised damage Principal modes of deterioration- Sheave block• At cross-over points-localised damage • Rope running through sheave :wear/wire breaks/corrosion• At pick up point-corrosion/wear/broken wires • Ability of sheave to freely rotate• Any malfunctions/deformations in the rope • Suitability of groove profile • Any damage to sheave block Sheave Groove ProfileAreas of Deterioration Simple two fall reeving system Wrong• Witness passage of rope through complete operating cycle Wrong• Determining areas where greatest deterioration is likely to occur (e. g. coinciding with pick-up of load)
WHERE TO EXAMINE-CRITICAL AREASINSPECTIONCritical points that should be considered for careful inspection on most installations would includethe following:PICK-UP POINTS - Sections of rope which are repeatedly placed under stress when the initial loadof each lift is applied, such as sections in contact with SheavesEND ATTACHMENTS - At each end of the rope two things must be inspected, the fitting that isattached to the rope, or to which the rope is attached and the condition of the rope itself, where itenters the attachmentEQUALIZING SHEAVES - The section of a rope that is in contact with and adjacent to suchsheaves as on boom hoist lines should receive careful inspection.DRUMS - The general condition of the drum and condition of grooves if drum is grooved, shouldreceive careful inspection - as should the manner in which the rope “spools” onto the drum.SHEAVES - Every sheave in the rope system must be inspected and checked with a groove gauge.HEAT EXPOSURE – Be especially watchful for signs that a rope that has been subjected toextreme heat or to repetitive Heat exposure.ABUSE POINTS - Frequently ropes are subjected to abnormal scuffing and scraping, such ascontact with ross - members of a boom. Look for “bright” spots.It must be kept in mind that minor - and frequently major - differences exist between installations,even on machines of a similar design.Therefore, points on each rope selected for close examination will necessarily require the bestjudgement of the Inspector.
EXAMINATION OF ROPES THROUGH SHEAVE INSPECTING SHEAVES
INTERNAL EXAMINATION AND AT ROPE TERMINATIONS OF ROPES– Rope MUST NOT be under any tension– Attach clamps approximately 100-200m apart– Contra-rotate clamps to unlay outer strands– Ensure strands are not excessively moved - avoiding any permanent deformation– Manipulate strands with probe to facilitate examination– Check - presence of any interwire pressure presence of any broken wires Proper Method of Installing Cable Clips degree of corrosion state of internal lubrication– Apply dressing– Apply additional reverse torque to re-bed strands on core
DISCARD CRITERIA WIRE ROPE SLINGAssessment and Discard Criteria• BROKEN WIRES – These can cause • Injury to user‟s hands. ·Loss of Strength – Randomly distributed wire breaks • Not to exceed 5% of the total in any length of 10d. – Localised breaks • 3 broken wires in a close group or in any one strand within a length of 6d - withdraw from service.• EXCESSIVE WEAR – Rope loss of diameter must not exceed 10% from nominal.• CORROSION – This causes loss of flexibility and roughness to the touch. Withdraw the sling and refer to supervision if necessary.• SIGNIFICANT DISTORTION – This appears as kinking, crushing, core collapse, knotting or other permanent deformation. Withdraw the sling and refer to supervision if necessary.• HEAT DAMAGE – Look for evidence of discoloration, loss of lubricant, pitting and the presence of weld blobs.• DEFECTIVE OR DAMAGES FITTINGS, FERRULES OR SPLICES – Opening up or cracking of hooks, – The effect of friction on the bearing surface of a soft eye – Fractured wires on the outside surface of the eye, for instance where a soft eye has been used with a very small pin – The effect of bursting stress at the throat of any eye due to the use of a pin of excessive diameter or certain types of thimble – Concentrations of broken wires near to terminations (to the ferrule or splice or in the spice) – Pulling out of the splice or ferrule – Severe crushing or abrasion of the ferrule or hand splice – Cracks in any ferrules – Closing of the thimble – Distortion and wear of links
MAINTAINANCE OF WIRE ROPE SLINGPURPOSE OF LUBRICATION FREQUENCY OF LUBRICATION Initial factory will not last Recommended at least quarterly Depend on the usageGOOD LUBRICATION CHARACTERISTIC Working environment Corrosion resistance Water repellent Penetrating ability Temperature stability
SAFE USE OF WIRE ROPE SLINGS DO NOT JOIN SLINGS BY THREADING THE EYES ALWAYS USE A SHACKLE OF AT LEAST THE SAME SWL TO JOIN SLINGS TOGETHER MAIN LIFTING RING (Min dimensions FERRULE (STAMPED WITH DATA) 270mm by 140mm)MASTER ASSEMBLY ALL WIRE ROPES TO BS 302 THIMBLES TO BS 464 PERMANENTLY MOUSED SHACKLES OPTIONAL ANTI-THEFT RING SPLIT (PERMANENTLY MOUSED) PIN SHACKLES TO BS 3551 OR PR-C-271B PINS TO BE SECURE PLASTIC OR WIRE TIE-WRAP
SAFE USE OF WIRE ROPE SLINGSNever use a sling that is knotted or kinked.Never drag a sling from under a load.The minimum radius around which a sling can bebent is 3 times the diameter of the sling wire rope.Never overload a sling.Never lift a container on two slings only.Keep slings away from welding and cuttingoperations.
SAFE USE OF WIRE ROPE SLINGS IF A LOOP IS PULLED THIS IS THE RESULT
SAFE USE OF WIRE ROPE SLINGS NEVER TIE KNOTS IN SLING LEGS TO REDUCE THEIR LENGTH
SAFE USE OF WIRE ROPE SLINGS NO -Dragging slings from under a load
SAFE USE OF WIRE ROPE SLINGSSLINGING TUBULARSTubulars include items, such as, Drilling tubulars, Scaffold Tubes, Construction pipe work, etc.It is DANGEROUS PRACTICE to bundle tube with steel angle, channel, etc. Small bore tubecould lay loose in the gaps between differently shaped items of steel, with the possibility of itsliding out when lifted. If falling from height, it would then become a potential spear - withpossible serious consequences !GENERAL PRINCIPLES:Only Tubulars of the same diameter should be bundled together.The number of tubes in each bundle should be such, that the middle tubes are gripped and willnot slip out of the bundle.Tubulars should always be slung with two slings, each of which has a SWL at least equal tothe gross weight of the Load.Slings should be placed at equal distance, [approximately 25% from the ends of the load.They should be wrapped around the load twice (DOUBLE WRAPPED)Excessively long tubular bundles should have a tag line attached to one sling.Clamps/ Bulldog clips should be used on the reeved wire, to prevent loosening. A tie wrapshould be used on the reeved eye of the sling to prevent it from slipping over the bulldog.Transportation frames are considered best practice
SAFE USE OF WIRE ROPE SLINGSDOUBLE WRAP AND SECURE WITH TUBING BUNDLE SMALL DIAMETER TUBINGCLAMPSLINGS OF EQUAL LENGTHG SECURE METHOD OF STORAGE/ TRANSPORTATION OFBATTENING DOWN TUBING It is sometimes imagined that slings in choke hitch can be made more secure by striking the eye of a sling in an attempt to force the bight into closer contact with the load. This dangerous malpractice is often called „battening down‟. The bight should be allowed to assume its natural angle which will be about 120
SAFE USE OF SLINGS- WEDGE SOCKETWedge sockets are among the simplest devices for anchoring a wire rope for any purpose. Theyare intented for on-the-job attachment and for quick rope replacement. However, the efficiency of awedge socket is low- only 70 percent of the strength of the ropeThe wedge socket must be properly set up as per the relevant Standard BS 7166, or equivalentProtruding rope shall be a length of 6xdiameter of the ropeWedge-type rope sockets should be inspected for damage to rope, wedge and socketThe wedge should be removed with a punchCorrect methods of fitting rope to wedge and use rope grips..
WIRE ROPE SLING- TEST1. Name a defect found in wire rope 4. Name each part of the diagram sling ? below:- a. Broken wire 1) b. Bird caging c. Loosed pin 2) d. Corroded/Rusty2. Can you use sling with 5% of broken wires. 3) a. Yes b. No3. Can you use damage wire rope sling? a. No 4) b. Yes