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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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Crown- and Valley Wire Breaks
 
Under normal operating conditions single wires will break due to material fatigue on the CROWN of a strand. ALL wire rope removal/retirement criteria are based on FATIGUE wire breaks located at the CROWN of a strand. (click here for more details)
     
CROWN Fatigue Breaks
 
 
Example: Severe crown wire breaks on a 10-strand overhead crane wire rope. Crown breaks originate at the OUTSIDE of the rope at the contact point between rope and sheave/drum.
   
 
Crown wire breaks on a PythonŽ Lift non-rotating wire rope.
 
  Remove wire rope from service if you detect even a SINGLE valley wire break ONLY. Valley breaks hide internal wire failures at the core or at the contact between strand and core.
 
     
     
VALLEY Wire Breaks
 
 
Example: Valley wire breaks on a 8-strand overhead crane wire rope.
   
 
Valley breaks originate INSIDE the rope. Condition of the inner strands of the same rope as above. The core has completely failed and immenent catastrophic rope failure will be the result.
     
A single valley wire break on a 19×7 rotation resistant rope.   Condition of core under that same single valley break. Note the extreme notching of individual wire and the countless wire breaks. Such a condition is hidden under just a single (1) valley break!
     
FATIGUE wire breaks are typically
squared off straight across the wire.
 
On the right and left a typical cut-and-cone break pattern. The wires in the center of the photo are a combination of fatigue and shear break.
TENSILE wire breaks are characterized by
their typical 'cup and cone' appearance.
 
 
     
     
LAY DIRECTION AND
MULTIPLE LAYER DAMAGES

Damages caused by connecting
a right hand to a left hand lay rope
 
These 3 picture show what happens when you connect a left-lay rope to a right-lay rope, as done with this boom pendant extension. Both ropes are opening up to the point where the strands are nearly parallel to each other; they completely untwisted themselves and developed excessive wire breaks.
 
 
   
 
     
     
     
Damages caused by multiple layer winding
 
 
 
 
 
 
The result of such non-tensioning of the layers are looping of individual wires, completely crushed strands, total deterioration of a non-rotating rope due to gross neglect of inspection procedure.
 
NOTE: For a more indepth discussion on wire rope discard and inspection we suggest to attend our "Wire Rope" and "SlingMax® Rigger's Mortis Seminar".
Call 1.800.457.9997 for details and dates.
     
     
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