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  Return to Wire Rope Main Page and Detailed Wire Rope Data  
    Technical Information  
  Use and Care of Wire Rope  
  Wire Rope is a Machine  
    Installation of Wire Rope:  
  Foreword, Measuring the rope diameter  
  If you have to cut a rope  
  Unreeling the rope  
  Connecting the old rope to the new rope  
  Rope lay direction versus Drum Grooving  
  Winding on to the drum  
  Installation of Wedge Sockets  
  Using your rope for the first time  
  Efficiency ratings of end terminations  
    Inspection of Wire Rope:  
  How to inspect Wire Rope  
  Crown- and Valley Wire Breaks  
  Number of broken Wire Discard Tables  
  Reduction of diameter, Rope Wear  
  Rope Stretch, Core Wire breaks  
  Mechanical damages  
  Corrosion, Rope Removal and Cause  
    Maintenance:  
  Inspection of Sheaves and Drums, Dimensions of Groove Radius  
  Cut and Slip Procedure, Lubrication  
    Rope Properties & Data:  
  Tensile Strength and Fill Factor  
  Strand- and Swage Compaction  
  Rotation Resistant and Non-Rotating Wire Rope  
  Sheave and Drum Dimensions  
  Relative Service Life, Loss of Strength over Pins, Why Multistrand Ropes  
Technical Information – Installation of Wire Rope
     
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Using your rope for the first time
 
Break-In Period
After installing a new rope it is necessary to run it through its operating cycle several times under light load and at reduced speed. This allows the rope to adjust itself to the working conditions and enable all strands and wires to become seated. Depending on rope type and construction some rope stretch and a slight reduction in rope diameter will occur as the strands and core are compacted. The rope is less liable to be damaged when full load is applied.

The initial stretch (constructional stretch) is a permanent elongation that takes place due to slight lengthening of the rope lay and due to a slight decrease in rope diameter.

Constructional stretch generally takes place during the first 10-20 lifts, and increases the rope length by between 1/2% for fiber core rope, approx. 1/4% for 6-strand steel core rope, and approaches zero for compacted Python ropes.

I you have the chance and the equipment configuration allows this, disconnect the rope end after the break-in-period to allow any possible torque and twists which may have developed during installation and the break-in-period to be released at the end connection.
  Equipment Testing
In many cases the crane equipment has to be tested prior to use. Proof testing requires to purposely overload the crane to varying degrees. The magnitude of overloading depends on the type and capacity of the crane and which governing authority certifies the equipment. The test may impose an overload of between 10% and 100% of the crane's rated capacity.

Under NO circumstances must the crane be tested prior to the break in procedure of the wire rope. If you overload a rope which has not yet been broken in, you may inflict permanent damage to the rope.

Equipment with multiple layer windings call for additional caution. As mentioned before, severe overloads of the top layers may damage the lower ones or may crush the rope. If possible, test the crane with the rope spooled in the first drum layer only.

If the crane is equipped with a smooth drum, special care must be taken to ensure that the rope does not cross-wind over itself when testing the crane. After testing (overloading) you have to repeat the spooling procedure as outlined here 'Winding on smooth or flat faced drums'.
 
     
     
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