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Technical InformationProduct Safety: Instructions & Warnings on the use of steel wire ropeA groove diameter of 7.5% greater than the nominalrope diameter is normally acceptable. However incertain cases experience has shown that clearancesbetween 10 and 12.5% are required to obtainoptimum performance.Before installing a new rope all sheave groovesshould be checked to ensure they provide therecommended clearance.Drum GroovesOn single layer drum hoists spiral grooving isrecommended. Where multilayer coiling is necessarythen parallel grooves or one of the patterned coilingsystems should be used. In all cases correct pitch,clearance and groove depth are essential to obtaingood rope performance.When a new rope is fitted a variation in sizecompared with the old worn rope will be apparent.The new rope may not fit correctly into the previouslyworn groove profile and unnecessary wear and ropedistortion is likely to occur. This may be remedied bymachining out the grooves before the new rope isinstalled. Before carrying out such action the sheavesor drum should be examined to ensure that there willbe sufficient strength remaining in the underlyingmaterial to safely support the rope.The competent person should be familiar with therequirements of the appropriateapplication/machinery standard.Note: General guidance to users is given in ISO 4309 Code ofpractice for the selection, care and maintenance of steel wire rope.Transfer the wire rope carefully from the storage areato the installation site.CoilsPlace the coil on the ground and roll it out straightensuring that it does not become contaminated withdust/grit, moisture or any other harmful material.(See Fig. 5)Dimensions for grooving of drumsGeneral recommendations for stranded ropesP = nominal diameter + 5%R = nominal radius + 7.5%A gap between the last turn on the bottom layer ofrope on the drum and the flange can be corrected byfitting a packing (or false cheek) of suitable thicknesson the inside of the flange.WARNINGFailure to carry out any of the above could result inunsatisfactory and unsafe rope performance.Note: Grooves must have clearance for the rope and provideadequate circumferential support to allow for free movement of thestrands and facilitate bending. When grooves become worn and therope is pinched at the sides, strand and wire movement is restrictedand the ability of the rope to bend is reduced. (See Fig. 4)Fig 5If the coil is too large to physically handle it may beplaced on a ‘swift’ turntable and the outside end ofthe rope pulled out allowing the coil to rotate.(See Fig. 5)WARNINGNever pull a rope away from a stationary coil asthis will induce turn into the rope and kinks willform. These will adversely affect ropeperformance. (See Fig. 6)Fig 4WRONGWRONGFig 6WRONGNote the kinksformingSheave groovetoo narrowSheave groovetoo wideRIGHTSheave groove correctlysupporting the rope for33% of its circumference48 BRIDON Mining