Inspection of Wires

ROUTINE INSPECTION

DISCARD CRITERIA,MAINTENANCE & RECORDS

ACCOMMODATIONLADDER WIRES

LIFEBOAT WIRES &ELEVATOR WIRES

PILOT HOIST WIRES &MOORING WIRES

CARGO WIRES &LASHING WIRES

Page 3 Page 4 Page 5 Pages 6-7 Pages 8-9 Pages 10-11INSIDE:

Wire Ropes and Their Uses

Wire Construction

Wires have for many years played an integral role inthe daily operation and function of nearly everycommercial vessel afloat. Applications will varyaccording to vessel type and purpose. The use, careand maintenance of wires should be included inevery vessel’s safety management system. However,accidents and incidents involving wires continue tooccur and the question arises as to why.

The scope of this special issue of Signals will cover

some of the specific demands on wire ropes used on

board and will address the inspection, maintenance,

certification and handling requirements of each.

Useful sources of reference, including international

conventions and standards, are provided on the

back page.

Before discussing the use and maintenance of

ship’s wires it is useful to understand how

wire construction is tailored towards different

applications. Wire rope is fabricated from strands of

precise individual wires. The configuration of the

wires and strands making up the wire rope is

designed and manufactured to be able to work

together and move with respect to one another to

ensure the rope has the flexibility necessary for

successful operation under tensile loading.

The wire material is carefully processed and drawnfrom selected grades of steel to predeterminedphysical properties and sizes. A number of finishedwires are then laid together helically in a uniformgeometric pattern to form a strand. The requirednumber of suitably fabricated strands are laidsymmetrically with a definite length of lay around acore to form the finished wire rope.

In addition to properties such as material strength,minimum breaking load and corrosion protection,wire rope is identified by its construction - typically,the number of strands in the rope and the number ofwires in each strand. For example, a wire rope of 6 x 36 construction denotes a 6-strand rope, witheach strand having 36 wires.

The core running through the centre of the wire maybe fibre, or of wire construction itself. For example,crane wires on ships are commonly configured withan independent wire rope core (IWRC) or wire strandcore (WSC) as opposed to a fibre core (FC).Identification numbering, such as 14/7 & 7/7/1,refers to the respective arrangements of the strandand core wires’ construction.

The strand pattern comprises various combinationsof wire diameters arranged to give differentproperties such as flexibility and fatigue, crush andabrasion resistance. Generally, a small number oflarge wires will be more abrasion resistant and lessfatigue resistant than a large number of small wires. The strands are often made up from threestandard wire arrangements known as Filler, Sealeand Warrington.

Filler (F) – Characterised by the small spacer wires that lie in the gaps between strands of theinner layer to help position and support the outerlayer. They provide crush resistance and flexibility.

Seale (S) – Characterised by having equally sized wires in the outer layer with the same numberof uniform but smaller sized wires in the inner layeraround a central core wire. The arrangementprovides good abrasion resistance but less fatigueresistance.

Warrington (W) – Characterised by having one ofits wire layers made up of an arrangement ofalternately large and small wires. This arrangementprovides good flexibility and strength but lesserabrasion resistance.

The notation WS, for example, is a blend of theWarrington and Seale patterns. In a typical wire ropeconstruction such as 6 x 36 WS-IWRC, combinationsof the three strand patterns are used because of thenumber of wires. Wire rope sizes could become toolarge if only one of the three standard patterns wereused. The outer layers of the strands have equallysized wires whilst the layer underneath, has wires ofalternately large and small diameter.

Continued on page 2

SIGNALSSPECIAL

Special Edition of the Loss Prevention newsletter for North of England Members

ISSUE 10 APRIL 2007www.nepia.com

Wire construction Source: Certex

Centre wire of strand

Complete strand

Wire rope core

Cross section of 6x25 IWRC Source: Certex

6 x 36 WS-IWRC Warrington Seale Wire

Source: N Thompson

Outer wire Centre wire

Core wiresInner wire

2 WIRE CONSTRUCTION

Right hand regular lay

Right hand Lang’s lay

Left hand regular lay

Left hand Lang’s lay

Wire rope layThe helix or spiral of the wires and strands in a ropeis known as the lay and there are several basic types.

Regular (ordinary) lay – This denotes rope in whichthe wires are twisted in one direction, and thestrands in the opposite direction to form the rope.The individual wires appear to run roughly parallelto the centre line of the rope. Due to the differencein direction between the wires and strand, regularlay ropes are less likely to un-twist or kink. Regularlay ropes are also less subject to failure fromcrushing and distortion because of the shorterlength of exposed outer wires.

Lang’s lay – This is the opposite to regular lay - thewires and strands spiral in the same direction andappear to run at a diagonal to the centre line of therope. Due to the longer length of exposed outerwires, Lang’s lay ropes have greater flexibility andabrasion resistance than do regular lay ropes.Greater care, however, must be exercised inhandling and spooling Lang’s lay ropes. These ropesare more likely to twist, kink and crush than regularlay ropes.

Regular lay is the most common form of wire ropefor cranes and usually furnished for all ropeapplications unless otherwise specified.

The lay-length is the linear distance a single strandextends in making one complete turn around therope. Lay-length is measured in a straight lineparallel to the centre line of the rope, not byfollowing the path of the strand.

Strength The responsibility for determining the minimumstrength of a wire rope used in a given system restswith the manufacturer of the machine, appliance orlifting equipment. As part of this process, theyshould have taken into account any relevantregulations or codes of practice governing thedesign of the rope – often referred to as thecoefficient of utilisation – and other factors that

might influence the design. These include the designof the sheaves and drums, the shape of the grooveprofiles and corresponding radius, the drum pitch,and the angle of fleet – all of which have an effecton rope performance.

Once the strength (referred to as minimumbreaking force or minimum breaking load) has beendetermined, it is then necessary to consider whichtype of rope will be most suitable. For instance, doesit need to be rotation resistant, have a good fatigueperformance, or be able to withstand particulartypes of abuse or arduous conditions?

Resistance to rotation Some applications require use of a low rotation orrotation resistant rope. Examples would be lifeboatfall wires, and main and auxiliary hoist crane wires.Such ropes are often referred to as multi-strandropes. Six or eight strand rope constructions are finefor low lifting heights or those with multiple fallsbut the most common choice to minimise loadrotation on a single part system, block rotation, or‘cabling’ on a multi-part reeving system, are lowrotation ropes.

When loaded, steel wire ropes generate ‘torque’ ifboth ends of a rope are fixed, or ‘turn’ if one end is unrestrained. The torque or turn generated willincrease as the load applied increases, and thedegree to which this happens will be influenced bythe construction of the rope. The tendency for anyrope to turn will be greater as the height of lift increases. In a multi-part reeving system, thetendency for the rope to cable will increase as thespacing between the parts of the rope decreases.Selection of the correct rope will help to prevent‘cabling’ and rotation of the load.

Some wires have been designed to minimiseproblems associated with cabling and load rotation.As a general rule, however, if a rotation resistantrope is not needed, then it should not be used. A sixor eight strand rope will always be more robust andbetter able to withstand excessive fleet angle andabuse than their more complex counterparts.

Fatigue resistance The rope’s fatigue resistance is also an importantfactor. Steel wire ropes will suffer from fatiguewhen working around a sheave or drum. The rate ofdeterioration is influenced by the number of sheavesin the system, the diameter of the sheaves and drum,and the loading conditions. If fatigue resistance isan issue, then it is wise to select a rope containingsmall wires, such as 6 x 36 WS (14/7 & 7/7/1), asopposed to a rope containing larger wires such as a6 x 19 S (9/9/1), which is more resistant to wear.Additional resistance to fatigue can be achieved byselecting a wire rope with a smoother surface thanstandard rope. This improves rope to sheave contactleading to reduced wear on both rope and sheave.An increased cross-sectional steel area andimproved inter-wire contact also ensures that therope will operate with lower internal stress levels.This ultimately results in greater bending fatigue lifeand long-term lower operating costs.

Resistance to abrasive wear Abrasive wear can take place between wire rope andsheave, and between wire rope and drum, but thegreatest cause of abrasion is often through‘interference’ at the drum. If abrasion is determinedto be a major factor in rope deterioration then a wire rope with relatively large outer wires should be selected.

A Lang’s lay structure, when the direction of lay ofthe wires in the outer strands is the same as that ofthe outer strands in the rope, also has better wearcharacteristics than a regular lay rope – when thedirection of lay of the wires in the outer strands is inthe opposite direction to the lay of the outer strandsin the rope.

Crush resistance ropes In multi-layer coiling applications, where there ismore than one layer of rope on the drum, it isessential to install the rope with some back tension.This should be between 2% and 10% of theminimum breaking force of the wire rope. If this isnot achieved, or in applications where high pressureon the underlying rope is inevitable – such as aboom hoist rope raising a boom from the horizontalposition – then severe crushing damage can becaused to the underlying layers. Use of a steel coreas opposed to a fibre core will help in this situation,and for this reason steel core ropes are alwaysrecommended for crane use. Additional resistance isoffered by wires which have a high steel fill-factorand these ropes are also recommended for multi-layer coiling operations where crushing on lowerlayers is inevitable.

It should also be noted that a Lang’s lay rope resistsinterference at the drum better than a regular lay.

Corrosion resistance ropes When the wire rope is to be used in a corrosiveenvironment – which applies broadly across themarine environment – then a galvanized coating maybe recommended, and where moisture can penetratethe rope and attack the core, plastic impregnationcould be considered. In order to minimise the effectsof corrosion, it is important to select a wire rope witha suitable manufacturing lubricant. This should be re-applied regularly while the rope is in service.

Wire rope on adjacent drum laps can causepoint contact and accelerated wear.

Compacted outer strands will reduce abrasionthrough improved contact conditions.

Resistance to wear Source: Certex

Wire construction (continued)

3ROUTINE INSPECTION

The time interval and extent of inspection andmaintenance for wires will vary depending on their construction and use. These should bedocumented by the manufacturer and incorporatedinto the vessels planned maintenance system by aresponsible officer.

As part of a continuous process of inspection forsigns of general deterioration and damage, thegeneral condition of all wire rope should bemonitored on a daily basis when in use. All wiresshould be subject to inspection by a responsibleperson before work commences and on completionof a wire rope’s work-cycle. This is of particularimportance if shock-loading is thought to haveoccurred during its operation.

When wire ropes are stored on drums, considerationshould be given to accessibility in order to determinethe timescale and logistics that will be involved in carrying out an examination of their entire length. Methods of examination should be includedwith maintenance logs to assist those involved with planning.

Although wires of six or eight strand constructionhold up to 90% of their strength in their outerstrands, it is the support provided by the core whichmaintains the wires efficiency and performance.Internal examination is therefore a vital componentof any inspection regime and may be carried out by acompetent person on board who has received theappropriate training.

The diagram above, shows a multi-strand rope thathas parted due to internal corrosion. The exteriorexhibited a minimum amount of corrosion, with nobroken wires and limited wear. The rope partedbecause the core had corroded to such a degree thatit collapsed causing the outer strands to impinge oneach other leading to a catastrophic wire failure.

Periodic ExaminationBy conducting frequent inspections and comparingthe condition of the wire with the previous set ofresults, a competent crew member can establish arate of deterioration, this can then be used toprogramme planned maintenance and anticipatewire replacement. Any change to the working cycleof the rope, including lifting heavier individual loads,greatly accelerates the rate of fatigue damage to thewire. Inspection and maintenance programmes,including the frequency of inspection, must bemodified to reflect this. Rate of occurrence of brokenwires is one of the measures used to determine thecondition of a wire. These are commonly referred toas the discard criteria.

Periodic examination should be carried out by acompetent person and will involve the completelength of wire rope. The detail of the examinationmust conform to the statutory requirements of local

legislation and the vessels Flag State. Internationalstandard ISO 4309 “Cranes - Wire ropes - Care,maintenance, installation, examination and discard“provides a framework for an examination and manyof the considerations that are required whendetermining how often they should be carried out. Itsscope includes deck, gantry, mobile, overhead andtravelling cranes as well as derricks with both guyedand rigid bracing. The application of the wire andhow often it is used, referred to as the number ofwork-cycles must also be taken into account.

Internal ExaminationSome specialized tools are required to carry out aninternal examination, These include:

• A ‘T’ needle (a flat spike with rounded edges) or a modified screwdriver for displacing outer strands to view the internal state of the core.

• Tape measure for measuring lay length.

• Chalk/electricians tape for marking any areas that require further examination.

• Cleaning materials (solvent) for removing debris or grease.

• Cheese wire (to remove debris/foreign matter from rope surface).

• Pliers for the removal of protruding parts of any broken wires.

• Clamps (wood or steel).

The examination should concentrate on evidence ofbroken wires, internal abrasion or friction, the degreeof corrosion and internal lubrication.

To carry out an internal examination, attach theclamps approximately 100mm - 200mm apart and contra-rotate to unlay strands. Care is requiredto ensure the strands are not moved to the point of causing permanent damage. The strands can be manipulated with the probe to facilitate the examination.

Once the examination is complete, a dressing can beapplied and reverse torque used to re-bed strandsonto the core. At a point of termination one clamp

will usually be sufficient and the procedure is thesame. Results must be recorded and compared to thediscard criteria.

Examining ropes running over sheavesThe lengths of rope running over sheaves are themost heavily worked parts of the rope and theexamination should concentrate on these. The stateof the drum anchorage, the area immediatelyadjacent to any termination and areas affected byheat damage should also be included.

The rope MUST NOT be under any tension during this process.

Routine Inspection

Internal examination Source: Certex

Terminal internal examination Source: Certex

Multi-strand rope that has parted due to internal corrosion Source: Certex

DISCARD CRITERIA / MAINTENANCE AND RECORDS4

Stress, abrasion, bending, crushing and corrosionare the most common sources of damage to wires.However, rotation, vibration, cabling and elongationmay also occur under certain circumstances. These can in extreme cases lead to catastrophic wire failure.

A detailed external examination should comparethe wire against the discard criteria for each type ofwire. These criteria are determined in consultationwith the manufacturer and include:

• Number of broken wires – The number of permissible broken wires will depend on the function of the wire and will include the rate of breakage occurrence and grouping of broken wires. For example, a single layer 6 x 7 fibre core wire rope used for a cargo wire should be discarded if 2 or more wires are visibly broken in a length equivalent to 6 diameters.

• Fractured strands – A strand that has completely fractured will require the wire to be discarded.

• Decrease in elasticity – This can be quite difficult to detect and it may be necessary to consult a wire specialist if it is suspected. Warning signs can include a reduction in the diameter of the rope, elongation of the lay length, signs of compression between strands along with the appearance of fine brown powder, and an increase in the stiffness of the wire.

Although broken strands may be absent from a wire that has a reduction in elasticity this

condition can lead to catastrophic wire failure and should result in the immediate removal of the wire from service.

• External and internal corrosion – External corrosion is easier to detect than internal. Discolouration will be accompanied by an apparent slackness between wires, which is a result of a reduction in the cross-sectional area of the wire. Corrosion can rapidly accelerate fatigue damage by causing surface deformation which can lead to stress cracking.

Other discard criteria may include:

• Heat damage.

• Rate of permanent elongation.

• Reduction in tensile strength.

• Length of service.

• Number of life-cycles.

• Broken wires at termination points.

• Reduction in diameter.

In addition to these considerations a detailedexamination of the wire will be required if there hasbeen a prolonged period of inactivity or a change tothe characteristics of the loading and dischargepattern of the vessel.

Evidence of broken wires should trigger a moreaggressive inspection regime, grouping of brokenstrands may indicate inherent weakness in the workprocedure for the particular wire affected andshould be monitored closely if not removed

from service. Once broken wires have beenidentified it is important that they be removedwithout further damage being done to the wire or injury to crew. Pliers may be used to work the broken wire back and forward until it breaks close to the strand. Non-destructive testingwill greatly assist wire inspection in applicationswhere there is an increased risk of internal wire damage. In circumstances where non-destructive testing is employed, initial referencedata must be determined as soon as possible afterthe wires installation to allow subsequentcomparisons to be made.

Discard Criteria

Maintenance and RecordsThe lifespan of any wire will depend to a greatextent on the way that it is maintained on board. The technical nature of wire manufacture demands that planned maintenance programmesbe developed in collaboration with themanufacturer before the wire is supplied to the vessel. Where lubrication or dressing of the wire is required this should be applied prior to the wires installation on board and reapplied atpre-determined intervals determined by themanufacturer. Lubricants may need to be workedinto the core of the rope during application if theyare to serve their intended purpose.

If cleaning of the wire is required before lubrication,care must be taken to ensure substances used arecompatible with the components of the wire andlubricants to be used.

Changes to operating practices and environmentalconditions will require planned maintenanceprogrammes to be flexible and anticipatory to ensurethe continued safe operation of wires on board.

Examination recordsDetailed records of examinations must bemaintained, this will allow those responsible toidentify patterns of damage occurrence. Thisinformation can then be used in conjunction withthe anticipated cycles of work to determineexpected deterioration prior to the next scheduledinspection. On detecting damage which exceedsthat predicted in the maintenance records, a re-evaluation of the life expectancy of the wire will be required and this should be followed by an inspection of all other associated machinery in order to establish the source of the accelerated damage. International standard ISO 4309contains examples of rope examination records for both individual inspections and running records. Details should include:

• Number of visible broken wires.

• Measurement of reduction in diameter.

• Degree of abrasion.

• Degree of corrosion.

• Degree of damage and deformation.

• Location of Damage and an overall assessment of wire condition.

The degree of deterioration may be assessed on apercentage basis:

20% = slight

40% = medium

60% = high

80% = very high

100% = discard.

StorageWhen not in use, wires should be stored in dryconditions or otherwise protected from chemicalsand substances that may harm their protectivedressing or lead to corrosion.

ACCOMMODATION LADDERS 5

Accommodation LaddersAccommodation ladders are the most commonlyused means of access to ships. On vessels that havelarge freeboards, they may fulfil the role of generalaccess when in port and facilitate pilot boardingand disembarking at the beginning and end ofpassage. They are generally located on the maindeck, constructed in a composite fashion withcollapsible hand rails and platform. This allowsthem to be stored with minimum intrusion into deckspace when the vessel is on passage.

The complex nature of this semi-permanent designmay cause problems. Removable stanchions andhinged components are often damaged by excessivewear during the rigging and dismantling process.

Article 15 of International Labour Organization(ILO) Convention 152 requires a vessel’s access to be“adequate, safe, properly installed and secure”.However, the lack of specific guidance makingreference to periodic inspection of accommodationladders in the existing regulations contained inchapter 1 of the International Convention for theSafety of Life at Sea (SOLAS) - regulations 7 and 8 -may have inadvertently resulted in their exclusionfrom detailed planned maintenance regimes.

Construction of accommodationladder wireThe stowage location of ladders on high freeboardvessels can require them to be lowered a significantdistance to the vessel’s shell door access. This canrequire large amounts of wire to be spooled onwinch drums. Wire used for this purpose must becompact, have a small diameter and be flexibleenough to rotate around the multiple sheaveconfigurations associated with these ladders.

Strands constructed of 36 wires give good flexibilitywhile maintaining shape and geometry with anindependent wire rope core. This reduces the effectof compression and crush damage.

Principal causes of damage• Corrosion – Storage on the main deck exposes

the wire to high levels of salt water contamination. The small diameter of wire required limits the effectiveness of internal core lubrication and weakens the wire’s resistance to corrosive damage.

• Abrasion – Damage often occurs as a result of pulley and sheave seizure, wires can be damaged and kinked during rigging and dismantling. Poor supervision of ladders landed on the quay may result in bights of wire being exposed to quay surface abrasion, contamination of lubricant and crush damage.

• Cutting in – This occurs when rope buries itself under tension in a wire that has been spooled poorly underneath. If not monitored closely, this can lead to jamming causing counter rotation, crushing and kink damage.

• Crushing – Uneven spooling can result in crossed wires on the drum - under load this can result in crush damage. This may also occur to exposed wire which have become snagged or nipped on the quayside.

• Fatigue – The rate of fatigue damage is accelerated by frequent bending of the wire while under load - tight nips round small diameter pulleys and kinking damage during rigging are examples. The rate of fatigue is accelerated by poor lubrication and exposure to corrosion damage.

Care and handlingThe complex nature of ladder construction requiresthat the rigging process be supervised by aresponsible officer. During this process a carefulinspection should be conducted to ensure eachcomponent of the ladder is free from damage, fit forpurpose, secure and suitably lubricated. Thesupervising officer should inspect the wire for signsof damage and fatigue. Care should be taken toensure a suitable amount of back tension is appliedduring spooling. This will reduce the likelihood ofjamming and crush damage when load is applied to the winch.

Most ladders are designed to rest on the quaysideand pivot at the point of attachment to the ship’shull. This can result in a significant concentration ofloading stress, often compounded by movement ofthe vessel on the berth. Supervision of the vessel’saccess can monitor the extent of this movement andprevent the ladder becoming overloaded when largegroups are assembled waiting to board or disembark.This is particularly important when the vessel is atanchor and the ladder is entirely suspended from thewire and davit arrangement. There have been anumber of fatal accidents under thesecircumstances with suspension wires parting,dropping ladders into the water. Signs indicatingmaximum loading should be attached to the ladderboth at the top and bottom to advise on the capacityof the ladder at any one time.

Maintenance and inspectionAn inspection by a responsible person should takeplace prior to the preparation of the ladder for useand subsequent to dismantling. This should includewires, all moving parts and points of attachment. Thefrequency of routine inspection and examination ofthe wire and associated equipment should be carriedout at a time interval which has been determinedappropriate by the Flag State administration andshould reflect the frequency of use.

If no guidance is provided by the Flag State it maybe prudent to adopt, as a minimum, the frequencyof examination for the pilot hoist and at each survey for the ship’s Safety EquipmentCertificate. Storage on the main deck exposes theladder, wire and winching mechanism to theextremes of environmental damage. If possible, wireshould be removed from winch drums before thevessel embarks on a long ocean voyage. If this is impractical, maintenance procedures shouldincorporate particularly aggressive lubricationregimes to compensate and suitable protectivecoverings should be used when the ladder is not in use.

Discard criteria should take account of the highlevels of corrosion associated with this application.

Cross section of 6 x 36 IWRCaccommodation ladder wire

Source: Certex

6 LIFEBOAT WIRES

Lifeboat systems have been subject to a great dealof scrutiny and investigation recently followingaccidents during statutory drills and maintenanceprocedures.

Several independent investigations have beencarried out by Flag State administrations and otherorganisations, including the UK Maritime andCoastguard Agency (MCA) and Marine AccidentInvestigation Branch (MAIB). Their conclusionsconcur that although causation may not be directlylinked to fall wire fatigue, its integral role in theoverall function of the system demands that thoseinvolved with the maintenance, inspection andoperation of lifeboat systems fully understand thecomplexity of the design and the contribution ofeach component.

Tricing pennants, gripe wires and hanging-offpendants are subject to similar sources of fatigueand misuse as fall wires and must not be overlookedduring inspection and maintenance programmes.Tricing pennants in particular have been identifiedby several research projects as being subjected toincreasing levels of misuse by poorly supervisedcrew members who overload them during drills bylowering boats to a point where the weight of theboat is mostly transferred from the fall wire to thetricing pennant. This dangerous practice can lead toslack fall wires, tricing pennant failure and thepotential for the consequential failure of the entiredavit structure. These risks highlight the importanceof a responsible officer supervising all activities thatinvolve movement of the boat and maintenanceactivity conducted by ship’s crew. Robust riskassessment procedures must precede allexamination and maintenance work.

ConstructionFall wires are required to be both flexible and stablein order to withstand the shock-loading androtation that can be present during lowering andrecovery, this requires a larger number of smalldiameter wires within the structure of the rope. Fallwires may be certificated to remain in service for upto five years. Lubrication and the corrosion resistantquality of its construction are therefore very important.

Principal causes of damage• Corrosion – Persistent exposure to environmental

extremes attacks the construction of fall wires. This is compounded by restricted access to long lengths of wire spooled on winch drums prohibiting penetrating dressing and lubrication.

• Abrasion – Seized davit sheaves and poor rope leads will accelerate the extent of damage to the larger number of exposed wires associated with this type of rope.

• Crushing – High freeboard vessels with a large amount of fall wire can suffer from “cutting in” during bad spooling with low back tension resistance increasing the likelihood of crush damage.

• Jamming – Uneven movement of davits and fall wires can lead to slack wire and bights forming between sheaves, unchecked this can result in misalignment and slippage of the fall wire off the sheave blocks jamming fall wires between sheave and davit structure.

Care and handlingThe accident investigations referred to earlierestablished that many of the incidents associatedwith lifeboats involved falls, sheaves, blocks, tricingpennants, and gripe arrangements.

Davit alignment relies on the precise tensioning offall wires. During lowering and recovery operationsdue diligence must be exercised to ensure evenspooling on winch drums. Smooth operation of thewinch control is necessary to avoid sharp judderingmovement of the davits and boat. Sheaves are oftenset at angles other than vertical. Slippage of wire offsheave blocks may result in the wire jammingbetween the sheave and cheek plate.

Crew members should be made aware of thedangers associated with lowering the boat toembarkation level beyond the point of weighttransfer from fall wire to tricing pennant. Largercapacity lifeboats that are bowsed-in alongside thevessel close to the davit head produce fall wireangles that are increasingly removed from thevertical. This produces increasingly large horizontal

moments and transfers unacceptable loads on toboth the davit arm and tricing pennant.

Maintenance and inspectionAll lifeboat wires are required to be inspectedweekly to ensure immediate readiness and monthlyto ensure they are maintained in good order. SOLASchapter 3, regulation 20, requires wires to be turnedend-for-end at intervals not exceeding 30 monthsand replaced at intervals not exceeding 5 years,subject to the condition of the wire. An alternativearrangement removes the need for ‘end-for-ending’if wires are inspected frequently and renewed atintervals not exceeding four years, subject to wirecondition.

More detailed maintenance and servicing guidelinesthan previously available have been promulgated bythe International Maritime Organization (IMO) inthe annex to IMO circular MSC/Circ.1206. Thisincludes:

• Release gear, including testing procedures for onload mechanism.

• Davit limit switches, sheaves and lubrication of moving parts.

• Winch power supply, controls and braking arrangement.

On vessels that are exempt from the launchingrequirements specified in International Conventionfor the Safety of Life at Sea (SOLAS) chapter III,regulation 19, planned maintenance schedulesshould take account of periods of inactivity.Discussion with manufacturers should determinesuitable dressings and lubricants to reflect thesetime intervals.

Reports and recordsDetailed records of inspection and maintenancework must be maintained and signed by themaintenance company’s representative, ship’smaster and those involved in conducting themaintenance programme. When repairs andservicing have been completed a statementconfirming that lifeboat arrangements remain fitfor purpose should be issued by the manufacturer’srepresentative or individual certificated by them.

Cross section of 34x7 IWRClow rotation steel corelifeboat fall wire

Source: Certex

Lifeboat WiresSuspended lifeboatWith the lifeboat in this positionthere is no load on the falls, so thetricing pennants and davit armssupport the entire weight of thelifeboat unaided.

7ELEVATOR WIRES

Elevator WiresElevators, or lifts, have been used on merchant vesselsfor many years. The wires used to operate them arereferred to as ‘hoist ropes’ and commonly haveeither a fibre or steel core and are of 6 or 8 strandconstruction. Wires are normally ‘pre-formed’,which ensures that an individual wire that parts willnot adversely change the geometry of the rope.

Both regular lay and Lang’s lay are used in hoistrope construction. Each has quite differentadvantages. Regular lay is easier to handle and willbe more resilient to crushing damage. Lang’s lay, withexternal wires being exposed to a longer lay lengthreduces wear more effectively than ordinary laythus improving the wires’ fatigue life. Whicheverconstruction method is selected, it is importantthat it be maintained throughout the operation ofthe elevator.

The fibre core, which may be natural sisal orsynthetic polypropylene, is impregnated withlubricant during manufacture to ensure a gradualrelease during the operation of the wire. Thisfacilitates mechanical movement between individualwires during bending and also offers some protectionagainst corrosion. Rate of lubricant release iscritical, too quick and the wire will slip on thesheaves, too slow and abrasion damage will result.

Combination wire construction utilises high tensilewire in the inner strands where their harder morebrittle construction can be protected by softer moremalleable low tensile strands on the exterior.Whichever wire is selected its construction must becompatible with the material used to manufacturethe sheave configuration.

Sets of lifting ropes must share identical propertiesthroughout their length, particularly their stretchcharacteristics under load. Manufacturers musttherefore ensure that pairs of rope are taken fromthe same production length.

Principal causes of damage• Fatigue – Flexibility is a vital component in a

hoist rope, continual bending and compression over sheave blocks will permeate throughout the lifespan of the rope, which, depending on working conditions is normally between 3 and 8 years. ‘Metal fatigue’ will produce spontaneous cracks that spread along the length of the wire until fracture.

• Abrasion – Insufficient lubricant will result in excessive internal wear known as fretting corrosion. Individual wires rub together producing an appearance similar to rust damage. This can lead to premature failure of the rope.

• Stretch – Slight discrepancies in diameter and elastic properties of a particular wire can result

in one of a pair of hoist ropes stretching slightly more than the other, or travelling more quickly through the rope cycle. Without a compensation mechanism in the lift operation this can lead to slippage on the sheave during use and affect the traction properties of the sheave and wire combination. Elastic stretch could commonly amount to about 6mm for every 10 metres of travel, permanent stretch can account for as much as 40mm per 10 metres of length when a wire is new, this is a symptom of ‘bedding in’ and will occur very quickly. A further stretch by as much as 60mm per 10 metre length is not uncommon over a number of years.

Maintenance and inspectionInspection intervals for hoist wires will bedependant on local administration and Flag Stateregulation. Subject to the number of rope cycles,industry best practice recommends a carefulexamination at six monthly intervals. The extensivebending which hoist ropes experience demandscareful assessment of fatigue cracks on individualwire strands. Inspections should also includetermination points and the means of attachment tothe car and counterweight. Sheaves are designed tobe softer than the wire and will shed slivers as aresult of rope slippage. If present, the cause must beinvestigated thoroughly.

High operating temperatures, traction, fast linespeeds and small bending ratios all reduce theefficiency of lubrication. Additional lubricationduring the operational life of the wire will clean andmaintain traction, penetrate into the wire assistingto repel moisture and reduce abrasion damage.Small amounts applied frequently will produce thebest results. Lubricating compounds must beapproved by the manufacturers. Sheave groovesshould exhibit a slight sponge like texture to the

touch when the wire is well lubricated. If the fingerremains dry, the rope requires lubrication. Governorropes should not be lubricated after installation.

In addition to discard criteria applicable to all wireropes, the following require particular attention:

• Surface wear damage to exterior wires caused by sheave traction and slippage.

• Inequality in tension between paired ropes.

• Excessive stretching, this can be monitored by the counterweight bottom over-run dimensions.

• Inequality in wire diameter throughout the length of the rope.

• External evidence of internal fretting corrosion.

In the absence of any national regulations orinstructions from the equipment manufacturer theabove table provides a general guide to broken wirediscard criteria.

A properly qualified competent person inspectingthe wire must be aware of the possible increase ininternal damage if operating sheaves are constructedfrom material other than cast iron or steel.

Care and handlingThere is little handling of hoist ropes once installed,however they are vulnerable to damage from sharpedges and corners during transportation andshipping. Ropes must be protected from wetdamage, humidity and heat. Lubricants can softenin strong sunlight and drip from the wires. Themethod of unreeling must ensure there is no kinkdamage and no contamination of the wire, pullingthe rope over sharp edges during installation canproduce torque which can de-stabilise its structure.Some manufacturers mark the rope to monitor theamount of twisting during installation, excessivetwisting can rapidly reduce the life expectancy ofhoist wire and may require correction.

Cross section of 8x19 dual tensile fibre or steel core wire elevator wire

Source: Certex

Number of Visible Broken Wires Single Layer Ropes with Fibre Core Operating in Cast Iron or Steel Sheaves

Condition

Broken wires randomlydistributed among theouter strands

Broken wirespredominating in oneor two outer strands

Adjacent broken wiresin one outer strand

Valley breaks

More than 12per rope lay*

More than 6 per rope lay*

4

1 per rope lay*

More than 15per rope lay*

More than 8per rope lay*

4

1 per rope lay*

More than 24per rope lay*

More than 15per rope lay*

More than 4

More than 1per rope lay*

More than 30per rope lay*

More than 10per rope lay*

More than 4

More than 1per rope lay*

Class 6 x 19 FC Class 8 x19 FC Class 6 x19 FC Class 8 x19 FC

Replace ropes or examine within aspecified period as stated by the

competent person Discard ropes immediately

Table of discard criteria for suspension ropes, governor ropes and compensating ropes

Source: Lift and Escalator Industry Association (LEIA)

*The length of one rope lay is approximately equivalent to 6 x d ( where d is the nominal rope diameter )

8 PILOT HOIST WIRES

MechanicalPilot Hoists

Pilot hoists were originally introduced to assistpilots to board ships with large freeboards as analternative to the accommodation and pilot laddercombination. Although pilots have sometimesexpressed reservations about their effectiveness,they are still in use and their safe operation isdescribed in detail in International MaritimeOrganization (IMO) Resolution A.889(21) - PilotTransfer Arrangements - adopted by the IMO in 1999.

Pilot hoists are sometimes semi-portable, in whichcase they require careful assembly under closesupervision allowing sufficient time for rigging and testing before the vessel is due to arrive at thepilot station.

ConstructionHoist wires are required to be made from flexiblesteel wire rope which is resistant to the corrosiveproperties in the marine environment. Theirconstruction will be very similar to that ofaccommodation ladder wires as they are exposed tosimilar sources of damage and fatigue.

Care and handlingPilot hoists consist of a moveable pilot laddersection hoisted or lowered from a suitableembarkation position. The necessity for twoindependent fall wires provides redundancy in theevent of one of the wires parting, however wiresmust be spooled carefully to maintain horizontalseparation on the winch drums. This ensures amaximum resistance to twisting and improves thestability of the hoist during use, another frequentconcern of pilots.

Great care must be exercised during lifting andlowering to ensure freedom of movement of allwires, sheaves and winch drums. Confined spaces at

shell door accesses can result in the close proximityof crew to moving machinery, care should beexercised to ensure hands are kept clear of fall wiresand drums during all hoisting activity.

If a hoist is being used, it is a requirement that aconventional pilot ladder be placed adjacent andaccessible so it is immediately available should theneed arise.

Maintenance and inspectionThe International Convention for the Safety of Lifeat Sea (SOLAS) chapter 1, regulations 7 and 8,require that pilot hoists be inspected at each annualor intermediate survey and at each renewal surveyfor the ship’s Safety Equipment Certificate. Thisshould be supplemented by on-board inspections bya responsible officer before and after each use andexamined at time intervals that both manufacturersand administrations consider appropriate. Analysisof planned maintenance and discard criteria willassist those on board in determining rate of fatigueand give an indication of permissible intervalsbetween examinations.

After installation an operating test of 10% overloadis required to the satisfaction of the administration.

Fall wire attachments to winch drums must beinspected to ensure secure fastening and must beable to support, hoist and lower a proof load of 2.2times the operational capacity of the hoist. Ifwastage and trimming of the hoist wires occurduring the life-span of the wire, great care must betaken to ensure sufficient length remains to permitthe maximum freeboard extension of the hoistwhile maintaining a minimum of three turns on thewinch drum.

Supervising officers are reminded of the importanceof checking the freedom of movement of the rollersthat are required to be fitted to the platform sectionof the hoist. If these rollers seize it can increase theload on the hoist wire and accelerate the rate offatigue damage. Power failure safety mechanismsand brake arrangements, should be tested during alowering cycle of the hoist at a distance of 5 metresfrom the vessel’s access. In the event of powerfailure a manual method of recovery should beavailable and must be fitted in such a fashion thatwhen it is engaged the power supply to themotorised winch is disengaged.

Cross section of 6 x 36 IWRC pilot hoist wire

Source: Certex

Cross section of 6 x 36 IWRC mooring wire

Badly spooled corroded mooring wire

Corroded termination

Poorly maintained roller leads

9MOORING WIRES

Mooring WiresWire failure continues to feature as a causativefactor in accident investigations into incidents thatoccur during mooring operations. These are almostalways serious and sometimes fatal. Each mooringoperation requires careful planning to ensure that asafe working environment for the crew can bemaintained while reducing the most likely sourcesof fatigue and stress damage to the wire.

Environmental exposure, abrasion damage andshock-loading all play a part in accelerating wirefatigue. Significant loads can be experiencedunexpectedly during any berthing manoeuvre.Incidents of this type will frequently exposeweakness within the structure of the rope andaccelerate fatigue to the point of wire failure.Designing a mooring wire with sufficiently robustqualities to withstand these external forces can beparticularly challenging - often a technical solutionto one source of fatigue may not be compatible withthe requirements demanded by the application.Maintenance regimes must therefore be designedto maintain the flexibility and subsequent life spanof the wire, while inspection programmes shouldenable a ships crew to identify symptoms of fatigueearly in order to protect the crew from theconsequences of wire failure.

ConstructionRopes that are constructed with wires of a largerdiameter will be less vulnerable to corrosiondamage, This characteristic is also desirable forabrasion resistance properties. However too large adiameter of wire will produce a less flexible ropeand reduce resistance to fatigue damage.Compromise is therefore required to produce a wirethat can satisfy the demands of mooring operationsand also be suitably lubricated to protect it fromcorrosion. Wires that may be exposed to crushingdamage benefit from a wire core and equal layconstruction, this will produce a more robust shapethat is less likely to deform under pressure. A typicalmooring wire construction consists of six strands of36 wires with an independent wire core (6x36IWRC). Mooring wires can be supplied from as littleas 10mm to over 100mm diameter.

Resistance to shock-loading can be difficult for amanufacturer to include in the design of a rope.Sometimes a length of nylon multiplait rope is fittedat the working end of the mooring wire to absorbmost of this shock. Fitting a nylon tail, which has alower breaking strain than the wire, also ensuresthat the cheaper and easier to replace tail, partsbefore the wire when accidental overloading takes place.

Principal causes of damage• Corrosion – This is a common cause of wire rope

failure. Mooring wires located on drums at theextremities of the vessel can be subject toextensive environmental exposure.

• Cutting in – This occurs when wire rope buries itself under tension in a wire that has been spooled poorly underneath it causing counter rotation during berthing and kink damage. If undetected by crew members this will not only seriously damage the wire and winch, but could result in serious injury to the crew.

• Crushing – This can seriously damage the structure of the rope by separating strands which will change the geometry of the rope reducing the breaking strain significantly.

• Abrasion – Some sources of abrasion damage are unavoidable - stevedores repeatedly dragging the wire over quayside knuckles will produce progressive wear in every mooring wire. Preventable abrasion damage occurs when a wire is led through poorly maintained leads which have become seized or have uneven corroded surfaces.

• Fatigue – The extent of a wire’s flexibility should be discussed with the manufacturer prior to purchase. Frequent excessive bending of the wire while under load will produce fatigue damage, which will be accelerated if the wire is being used beyond its design specification. Careful consideration should be given to the characteristics of the wire when old wire is being replaced by new. Before ordering new wire those responsible need to ensure that the diameter of the roller leads and pedestal rollers on board are compatible with the construction of the wire and the manufacturer’s recommendations.

Care and handlingHandling of mooring wire ropes is a hazardousactivity and all those involved should receiveappropriate instruction on the dangers andprecautions required to reduce the risk of injury.

Training should include the limitations of use andpossible causes and consequences of poor handlingand insufficient maintenance. Topics could includebut not be limited to:

• Avoiding sharp angles in mooring arrangements.

• Correct use of leads and pedestal rollers.

• Avoiding snap-back zones.

• Danger of broken strands.

• Hazards of lubricants in contact with skin.

• Precautions required when working with single drum, split drum and drum ends.

• Wires stored on drums.

Mooring operations are no different to any otherhazardous activity on board the vessel and require arisk assessment to be carried out as part of thebriefing and preparation process. The mooring planshould be discussed with all those who will beinvolved to establish the most appropriate leads androllers to be used for each wire.

Maintenance and inspectionBecause of the exposed location of mooring wiresand their vulnerability to fatigue damage, strictmaintenance and lubrication schedules must bemaintained to prevent corrosion. Wires should beremoved from winch drums for detailedexamination at a time interval based on themanufacturer’s recommendations and the wire’sdiscard criteria. The wire should be cleaned withproducts compatible with the wire, intendedlubricant and approved by the wire’s manufacturer.

During cleaning crew members must be aware ofthe possibility of broken wires and wear appropriatehand protection. Every broken wire detected shouldbe brought to the attention of the supervisingofficer. Wire manufacturers will stipulate thepermissible maximum number of broken strands ina given wire length.

A general rule of thumb for mooring wires would bebreakage in 10% of the visible strands in any lengthof wire equal to 8 diameters.

If this number is exceeded then the wire should becondemned and removed from service. Oncecleaned and examined, damage to the wire must berecorded in planned maintenance records andcompared to the manufacturers discard criteria andprevious damage notes. This is also an idealopportunity to inspect the end fitting of the wire tothe drum and check method of attachment. Whenthe responsible officer is satisfied with the wire’scondition it can be treated with the approvedlubricant and greased if required. Care must betaken to ensure that the lubricant penetratesbetween the surface wires and into the central coreof the rope. During re-spooling crew must ensuresufficient back tension is maintained, this will notonly protect the wire from crushing damage but willhelp prevent cutting in and kink damage duringfuture use.

Routine external examination should be incorporatedinto pre-arrival and departure checks in accordancewith the vessels safety management system:

• All leads, rollers and contact surfaces must be maintained to ensure they are kept smooth and free from signs of corrosion; this will reduce likely sources of abrasion damage.

• Pedestal and fairlead roller bearing surfaces should be kept lubricated.

• Maintenance of back tension during operation and spooling for inspection must be maintained.

• A more detailed examination should take place after any shock-loading or unusual event. Those involved should compare the condition of the wire to the manufacturer’s recommended discard criteria and should check for signs of elongation and bird-caging.

10 CARGO WIRES

Cargo wires are used in cranes, gantries and othercargo lifting appliances. Similar wires will also beused for other lifting operations such as storescranes and engine room gantries. The commentsapply to all such wires used in cargo and other liftingoperations.

Strength requirements of wire ropes are based onthe tensile forces imposed on them by the design ofthe crane or lifting appliance with an appropriatefactor of safety. Applicable safety factors for thewire ropes are set out in the design requirements forcranes and other lifting appliances by variousclassification societies and are primarily based onthe safe working load (SWL) of the equipment. Forship’s cranes or other lifting appliances ratedbetween 20 and 60 tonnes (SWL), the requiredbreaking strength of the wire is of the order of fourto five times the maximum designed duty load inservice. This applies to hoisting and luffing wires, theforces in which alter depending upon the orientationof the crane, jib and the dynamic influences duringoperation.

ConstructionThe most common wire construction for wire ropeson ship’s cranes or lifting appliances is the ‘singlelayer’ wire rope corresponding, as the namesuggests, a single layer of strands helically woundaround a core. Other types are manufactured such as‘rotation resistant’ or ‘multi-strand’ in which anumber of layers of strands are contra-helicallywound to reduce the rotational tendency and torquein the rope under tension. These ropes can also have‘compacted’ strands in which the individual wiresare not round but shaped to provide a greatersurface area of contact with a sheave and thusreduce the contact pressure.

Defects and damageInternational standard ISO 4309 provides acomprehensive listing of, and photographs, showinga number of defects that can occur on crane orlifting appliance wire ropes. Obvious defects such askinks and basket deformation in which the externalshape of the wire rope changes should be able to beidentified relatively quickly. External corrosionshould also be obvious during inspection.

Wire ropes should be frequently checked closely forother damage and defects, such as indications ofwear (flattening of wires) and broken wires in thestrands. The extent of broken wires in a given lengthand grouping of wire breaks are all factors that needto be considered when judging criteria for allowingthe rope to continue in service. Tables in standardsset out the relevant criteria although there aredifferences between the various referencedocuments and standards under the regulatoryrequirements in this regard.

Probably the most common defect within wire ropein which cursory examination of a greased rope canoften overlook is wear. This is shown by flattening ofthe round wire elements. Wear can be accelerated bydefective (non-rotating) sheaves with the ropeabrading around it or if the wire rope diameter islarger than, and not matched, to the sheaves. Toosmall diameter sheaves can also result in excessivebending of the rope. Eventually, flattening of thewires reduces the load bearing cross-section ofindividual wires, which can lead to wire fractures.Wear can also initiate fatigue. From a maintenanceand safety perspective of wire ropes, regularinspection and lubrication of sheaves in accordancewith the manufacturer’s instructions should be followed.

Examples of wear are shown in the two figures onthe left. In one it can be seen by the naked eye thatfracture of the wires has commenced due toexcessive wear. The scanning electron microscopephotograph in the other shows two crack frontspropagating from the flattened portion of the wirethrough fatigue that ordinarily may not be visible tothe naked eye.

According to ISO 4309, a 7% reduction in nominalrope diameter warrants discard of the rope even if nowire breaks are visible.

Whichever guideline document is used to judgecondition of a wire rope in use onboard a vessel, it isimportant to realise that crane or lifting appliancewire ropes should be considered consumable items,which require frequent examination, assessmentand maintenance.

Care and handlingThere is no set period for the expected lifetime ofropes. However, in practice a survey cycle period offive years would be a typical maximum lifetime forcrane or lifting appliance wire ropes. Of course,depending on the duty of the crane or liftingappliance and skill of operators, the hoist wire can beparticularly prone to external abrasion or crushingdamage. Such damage can occur in a single eventand possibly resulting in a relatively new wire torequire renewal. A wire, similar to a chain, is only asstrong as its weakest point.

Inspection and maintenanceRegular visual inspection, ideally before and afteroperations handling cargo, should be carried out onboard to check for damage and defects. Measurementof the rope diameter (scribed from the circlesurrounding the entire rope) should be made andrecorded regularly to monitor wear particularly in regions on the rope which regularly passes around sheaves.

Wire fracture caused by excessive wear

Source: N Thompson

Fatigue cracks Source: N Thompson

Cargo Wires

AcknowledgementsThe Association would particularly like to thank the following for their assistance with this special edition of Signals:

Nigel Thompson of Brookes Bell for his expert contribution on the subject of cargo wires.

Brookes Bell Jarrett Kirman LLP6 Brewery Square, Tower Bridge, London, SE1 2LF, United Kingdom. Telephone: +44 20 7403 3838. Website: www.brookesbell.com

Certex UK for their advice and recommendations on wire ropeconstruction and selection.

Certex UKCertex House, Trafford Court, Doncaster, South Yorkshire, DN1 1PN, United Kingdom.

Telephone: +44 13 0273 1000. Website: www.certex.co.uk

11CERTIF ICATION AND REGULATION

Wire is commonly used at sea for securing cargo.However, this use of wire ropes will not be dealtwith at length in the Special, as detailed guidanceon all aspects of the stowage and securing of cargo- including the use of wire ropes - is given in theAssociation’s Loss Prevention Guide entitled CargoStowage and Securing.

ConstructionA typical construction of lashing wire would be16mm diameter wire of 6x12 or 6x19 constructionwith a fibre core to ensure a suitable degree offlexibility. The size of the wire should always beappropriate to the size and weight of the cargoitems being secured.

Care and UseAlthough the diameter of the wire used shouldreflect the weight of the load to be secured, it mustbe borne in mind that as the diameter of the wireincreases the flexibility and therefore ease ofhandling will be reduced. Wire of diameter greater

than 24 mm and of construction 6 x 37, for example,is not flexible enough for lashing purposes.

Another consideration is that wire stretches when inuse - new wire will initially permanently stretchwhile it is settling and compacting, and will displayan elastic stretch whilst in use, as load increases. Thepermanent constructional stretch is likely to bebetween about 0.25% and 1.0% of the length ofrope, and the elastic stretch will be up to about 1.0%when the rope is under a load that is close to itsnominal breaking load. Thus, when a new wire ropeis used to lash a piece of cargo the lashing mightstretch by as much as 2% of its original length whensubjected to a high loading. For this reason, andbecause the cargo itself might move a little andsettle, lashings must be checked and re-tightened asnecessary at intervals throughout the voyage.

Single Use and Re-usableBecause wire will stretch and deform whensubjected to high loadings, wire rope used for

lashings is considered to be either single use whenit is discarded at the end of just one voyage or re-usable when it is not discarded until it is visiblyworn, but is not exposed to high loadings thatwould cause weakening.

Details of the loss prevention guide – CargoStowage and Securing – can be obtained from theAssociation’s website or the risk managementdepartment. Website: www.nepia.com

Cranes and other lifting appliances and their loosegear, including wire ropes, are subject to annual andordinarily, five yearly surveys, at which they are alsoproof load tested by the classification society. Detailsof the surveys are recorded in the vessel’s Register ofLifting Appliances and Cargo Handling Gear.

A documentary record of wire ropes in use on thecrane or lifting appliances, their identification,appropriate test certificates and dates of renewalshould be maintained onboard. When wires aredelivered to the vessel they must be accompaniedwith an appropriate certificate setting out thematerial strength, construction of the rope andbreaking load test of a sample.

Wire ropes on cranes or other lifting appliances areexposed to the marine environment and ordinarily agalvanised coating is recommended. Further ‘inservice’ maintenance and protection is alsorequired by regularly lubricating the rope with

appropriate grease dressing. In addition toprotection from corrosion, the lubricant shouldpenetrate and allow the strands and elementswithin the rope to move freely relative to eachother when their shape changes such as whenrunning around sheaves.

Relevant sources of internationalstandards and guidanceWith regard to crane or lifting appliance wire ropes,and guidance on their condition, classificationsocieties commonly refer to guidelines set out by either the International Labour Organization(ILO) or the International Organization forStandardization (ISO).

In the practical case of a vessel in port workingcargo, the vessel’s Flag State and classification

society may consider the condition wire ropes withreference to ISO but the port facility may complywith ILO convention C152 - Occupational Safetyand Health (Dock Work) Convention 1979 - and/or consider their own national standard to be applicable. In statutory terms, the safetyrequirements of the cargo handling gear and wireropes would be governed by the nationalregulations of the Flag State AND those of thecountry where the ship’s gear is being used.

In the UK, the Health & Safety Commission is thelegislative body and its document Approved Code ofPractice, Dock Regulations 1988 and guidance alsorefers to the ILO guidelines. Other countries willalso have their own legislative bodies and nationalstandards as appropriate.

Wire Rope Used for Lashing

Cross section of 34 x 7 IWRC low rotation hoist wire

Source: Certex Cross section of 6 x 36 IWRCcrone boom wire showingcompacted outer strands.

Source: Certex

‘Signals’ is published by North of England P&I Association Limited The Quayside Newcastle upon Tyne NE1 3DU UK Tel:+44 (0)1912325221Fax: +44 (0)191 261 0540 Email: [email protected] Website: www.nepia.com

12 FURTHER INFORMATION

• In this publication all references to the masculine gender are for convenience only and are also intended as a reference to the female gender. Unless the contrary is indicated, all articles are written with reference to English Law. However it should be noted that the content of thispublication does not constitute legal advice and should not be construed as such. Members with appropriate cover should contact the Association’sFD&D dept. for legal advice on particular matters. • The purpose of the Association’s risk management facility is to provide a source of information which is additional to that available to themaritime industry from regulatory, advisory, and consultative organisations. Whilst care is taken to ensure the accuracy of any information madeavailable (whether orally or in writing and whether in the nature of guidance, advice, or direction) no warranty of accuracy is given and users of thatinformation are expected to satisfy themselves that the information is relevant and suitable for the purposes to which it is applied. In nocircumstances whatsoever shall the Association be liable to any person whatsoever for any loss or damage whensoever or howsoever arising out ofor in connection with the supply (including negligent supply) or use of information (as described above).

Other useful relevant sources of international standards and guidance include:

General BS EN 12385:2002 Part 4 Steel wire ropes. Safety. Stranded ropes

for general lifting applicationsILO C152:1979 Occupational Safety and Health (Dock Work)

Convention ISO 2408:2004 Steel wire ropes for general purposes -

Minimum requirementsISO 2532:1974 Steel wire ropes – VocabularyISO 3108:1974 Steel wire ropes for general purpose -

Determination of actual breaking loadISO 3189:1985 Sockets for wire ropes for general purpose

Parts 1,2 and 3ISO 4345:1988 Steel wire ropes – Fibre main cores – SpecificationISO 4346:1977 Steel wire ropes for general purpose – Lubricants –

Basic requirementsISO 8793:1986 Steel wire ropes – Ferrule secured eye terminationsISO 17893:2004 Steel wire ropes – Vocabulary, designation

and classificationIMCA Guidance on the Management of Life Cycle

Maintenance of Non-Man-Riding Wire Ropes

Accommodation LaddersISO 5488:1979 Ships and marine technology – Accommodation

ladders ISO 5489:1986 Ships and marine technology – Embarkation ladders ISO 7061:1993 Ships and marine technology – Aluminium shore

gangways for seagoing vessels

Cargo WiresISO 4308–1:2003 Cranes and lifting appliances – Selection of wire

ropes - Part 1: General

ISO 4308–2:1988 Cranes and lifting appliances - Selection of wire ropes - Part 2: Mobile cranes - Coefficient of utilisation

ISO 4309:2004 Cranes – Wire ropes – Care, maintenance, installation examination and discard

Elevator Hoist RopesBS EN 81-1:1998 Safety rules for the construction and installation

of lifts. Electric lifts ISO 4344:2004 Steel wire ropes for lifts – Minimum requirementsBS EN 12385-5:2002 Steel wire ropes - Safety - Stranded ropes for lifts

Lifeboat Fall WiresSOLAS Chapter III, Reg 20 Operational Readiness, maintenance and inspectionSOLAS Chapter III, Reg 36 Instructions for on-board maintenanceSOLAS Chapter IX ISM Code, Part 10 Maintenance of ships equipmentIMO MSC.1/Circ.1205 Guidelines for Developing Operation and

Maintenance Manuals for LifeboatsIMO MSC.1/Circ 1206 Measures to Prevent Accidents with Lifeboats

Pilot Hoist WiresIMO Res. A.889(21) Pilot Transfer Arrangements SOLAS Chapter V, Reg 23 Pilot Transfer ISO 799:2004 Ships and marine technology – Pilot ladders

Vessels trading at sea are required to comply withthe regulatory requirements of their Flag State. It iscommon practice for the classification societies todeal with certification on behalf of the Flag State.Individual Flag States are ordinarily members ofInternational Maritime Organization (IMO), anagency of the United Nations, and in the case ofthe International Convention for the Safety of Lifeat Sea (SOLAS), all member states are signatoriesto these common minimum requirements as setout in the SOLAS regulations. Vessels should alsoadopt industry guidelines and codes of practice.

The International Labour Organization (ILO) is alsoan agency of the United Nations. The ILOconvention governing the testing, examination,certification and inspection of a vessel’s cargohandling gear and crane wires is C152 -Occupational Safety and Health (Dock Work)Convention 1979. The ILO Code of Practice booklet- Safety and Health in Dock Work - includesguidelines on the care and maintenance of wireropes and includes criteria for their discard.However, the proposals to enhance the health andsafety of dock workers and the booklet consider a

wide range of aspects regarding cranes and dockwork generally. With reference to crane wires, andin particular, the criteria for discard, the bookletcould be seen to be rather vague in its stipulations.Over 20 countries have currently ratified the ILOconvention but notable exceptions include the UKand USA.

Regulations concerning the testing, certification,thorough examination and inspection of wire ropewill be implemented by the competent authoritiesand organisations appointed by them inaccordance with the requirements of ILOConvention 152: articles 21 to 26. The conventionrequires that wire rope test certificates shouldinclude details of:

• The competent person who carried out testing and thorough examination, date, place and signature.

• Name and address of maker or supplier.

• Nominal diameter.

• Number of strands.

• Number of wires per strand.

• Type of core.

• Lay of wire.

• Date of test of sample.

• Quality of wire (N/mm2).

• Load at which sample broke (tonnes).

• Safe working load of rope (tonnes).

• Intended use.

The International Organization for Standardization(ISO) is a non-governmental organisation made upof a network of the national standards institutes ofmany countries co-ordinated by a centralsecretariat in Geneva, Switzerland. ISO 4309 -Cranes – Wire ropes – Care, maintenance,installation, examination and discard (currently inits third edition, 2004) - sets out morecomprehensive guidelines in comparison withthose included in the ILO booklet. It thereforefollows that, for the assessment of crane wire ropeson vessels trading internationally, following theguidelines of ISO 4309, which is an excellentreference, should demonstrate an acceptablemethod of good practice in the international arena.

Certification and Regulation