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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 – Inspection of Wire Rope
     
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Corrosion
 
Corrosion, while difficult to evaluate, is a more serious cause of degradation than abrasion. Usually, it signifies a lack of lubrication. Corrosion will often occur internally before there is any visible external evidence on the rope surface.

This is one of the reasons why we developed PYTHON™ wire rope with a plastic protected core. The plastic protects the core against corrosion and the user does not have to worry about undetected corrosion which may lead to a sudden and unexpected rope failure.
  Corrosion of the rope core not only attack the metal wires, but also prevents the rope's component parts from moving smoothly as it flexes.

Severe rusting leads to premature fatigue failure of single wires. When the rope shows more than one wire failure near a fitting, it should be removed immediately. To prevent abnormal corrosion, the rope should be kept well lubricated. In situations where abnormal corrosive action can occur, it may be necessary to use galvanized or stainless steel wire rope.
 
All removal criteria are based on the use of steel sheave.
  Fault   Possible Cause
  Accelerated Wear   Severe abrasion from being dragged over the ground or obstructions.
Rope not suitable for application.
Poorly aligned sheaves.
Large fleet angle.
Worn sheave with improper groove, size or shape.
Sheaves and rollers have rough wear surface.
Stiff or seized sheave bearings.
High bearing and contact pressures.
Sheaves/drum too small.
  Rapid Appearance of Broken Wires   Rope not suitable for application.
Reverse bends.
Sheaves/drums too small.
Overload and shock loads.
Excessive rope vibration.
Kinks that have formed and have been straightened out.
Crushing and flattening of the rope.
Sheave wobble.
  Corrosion   Inadequate lubrication.
Improper storage.
Exposure to acids or alkalis.
  Kinks   Improper installation.
Improper handling.
Slack rope pulled tight.
  Excessive localized Wear   Drum crushing.
Equalizer Sheave.
Vibration.
 
  Fault   Possible Cause
  Stretch   Overload.
Passed normal stretch and approaches failure.
  Broken Wires near Fitting   Rope Vibration.
Fittings get pulled too close to sheave or drum.
  Sheaves/Drums Wear out   Material too soft
  Pinching, Crushing,
oval Shape
  Sheaves grooves too small.
Not following proper installation and maintenance procedure on multiple layer drums
  Rope Unlays
(Opens up)
  Wrong rope construction.
Rope end attached to swivel.
  Reduction in Diameter   Broken core.
Overload.
Internal wear.
Corrosion.
  Bird Cage   Tight Sheaves.
Rope is forced to rotate around its own axis.
Shock loads.
Improper Wedge Socket installation.
  Core Protrusion   Shock loading.
Disturbed rope lay.
Rope unlays.
Load spins and rotates rope around its own axis.
     
     
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