WIRE ROPE IS A MACHINE. UNDERSTAND AND RESPECT IT.
General Use Statement
Wire rope is a machine, like any machine, it needs proper care and maintenance for optimal safety and long service life. For a better understanding of wire rope, we highly recommend reading and understanding the Rope User's Manual by the Wire Rope Technical Board.
Refer to our General Warnings and Instructions page for general rigging information. The warnings and instructions below apply only to Wire Rope and Cable.
Rated Capacity / Working Load Limit
Rated capacity is the load which a new wire rope may handle under given operating conditions and at an assumed design factor. A design factor of 5 is chosen most frequently for wire rope which equates to operating loads not exceeding 20% of the catalog Breaking Strength. Operating loads may have to be reduced when life, limb or valuable property are at risk or other than new rope is used. A design factor of 10 is usually chosen when wire rope is used to carry personnel which equates to operating loads not to exceeding 10% of catalog Breaking Strength.
See our General Warnings and Instructions guide for more information on:
Responsibility for choosing a design factor rests with the user.
Matching Attachment's Working Load Limit
Attachments must have at least the same Working Load Limit as the wire rope used. The rigging assembly can only be rated up to the weakest component minus any termination efficiencies.
Clips, sockets, thimbles, sleeves, hooks, links, shackles, sheaves, blocks, etc. must match in size, material and strength to provide adequate safety protection. Proper installation is crucial for maximum efficiency and safety.
Inspect Wire Rope Regularly
Use inspection instructions as guidelines only. Two of the most important prerequisites for inspecting wire rope are technical knowledge and experience.
Check the general condition of the wire. Also, look for localized damage and wear, especially at wire rope attachments. Inspect all parts that come in contact with the wire rope. Poor performance of wire rope can often be traced back worn or wrong-sized sheaves, drums, rollers, etc. Look for kinks, broken wires, abrasions, lack of lubrication, rust damage, crushing, reduction of diameter, stretch or other obvious damage. If any of these conditions exist or if there is any other apparent damage to the wire rope, retire the wire rope.
When in doubt about the extent of the damage, retire the wire rope in question immediately. Without laboratory analysis, it is impossible to determine the strength of damaged or used wire. Thus, you will not be able to tell whether wire rope with any amount of damage is safe to use. Retire the wire rope that is damaged. For specific inspection procedures check various OSHA, WRTB, ANSI, and ASTM publications.
Destroy, Rather than Discard, Wire Rope to be Retired
Wire rope that is not destroyed might be used again by someone not aware of the hazard associated with that use. Destroying wire rope is best done by cutting the eyes open, cutting any attachments, and cutting the body up into short unusable pieces.
Measuring Wire Rope Diameter
Wire rope should be measured on the peaks of opposing strands and never on the valleys. Below is an illustration that displays the correct method to measure wire rope diameter.
Wire Rope Diameter Tolerances
|Wire Rope Diameter (in)
Tolerances specified in Federal Specification RR-W-410-H