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  Wire Rope Selection  
  Technical Information:  
  Overview  
  Wire Rope Removal Criteria Tables  
  Rope Removal and Possible Cause  
  Fundamentals of Inspection and Handling  
  Measuring Wire Rope / Lay Direction  
  Tensile Stength and Fill Factor  
  Strand- and Swage Compaction  
  Bending Fatigue / Rope Service Life  
  Rotation Resistant and Non-Rotating Wire Rope  
  Sheaves and Drums  
Tensile Strength and Fill Factor
 
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The breaking strength of wire rope can be increased in two ways: either by increasing the wire material TENSILE STRENGTH or by increasing the rope's FILL FACTOR.
     
Tensile Strength
The wires of wire rope are made of high-carbon steel. These carbon steel wires come in various grades. Wire ropes are usually made of Extra Improved Plow Steel (EIPS) or Extra Extra Improved Plow Steel (EEIPS) which roughly equivalents to a wire tensile strength of
1960N/mm and 2160N/mm.

As one can see from the tables, the difference in the rope's breaking strengths by increasing the material tensile strength is only about 10%.
 
     
Fill Factor
In order to further increase the breaking strength of wire rope one has to increase the rope's fill factor.

The fill factor measures the metallic cross section of a rope and compares this with the circumscribed area given by the rope diameter. Traditional rope constructions 'fill' the rope diameter only up to about 58% with steel. Python® wire rope 'fill' the rope diameter up to 80% with steel. That is an metallic increase of about 38% which results in a similar increase in rope strength.

Two methods can be employed: Selecting a different rope CONSTRUCTION or COMPACTING/DIE DRAWING the rope/strands.
 
Fill Factor of different rope constructions
 
     
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