Wire rope is made of dozens or hundreds of wires that work together to support heavy loads, and it must be regularly inspected for broken wires, permanent bends, reduction in diameter, discoloration from heat, or other damage that could cause failure. The document provides guidance on inspecting wire rope and what to look for, such as allowing 12 broken wires in one lay or 4 broken wires in one strand, and recommends against using fiber core rope above 200°F or touching a live rope. It also includes demonstration ideas to help explain wire rope inspection to a crew.

1. Construction Safety Talks
Wire Rope Some things to know before you give your talk.
Inspection
Wire rope is really a machine made out of dozens and in some cases
No. 69 hundreds of wires that move independently but work together
providing a capacity of 20, 30, or 40,000 pounds. Each wire rope
has three basic components:
How This Talk
1. The core, which forms the foundation for the strands;
Applies To My
Crew: 2. Dozens of individual wires wound together to form a strand;
3. Strands that are laid helically around the core.
The wires will slide and adjust in a bend to accommodate the
difference in length between the inside and the outside of the bend
so that the wire rope can turn around a sheave or pulley without
breaking.
As a user, you should perform a daily visual inspection to spot any
gross signs of damage, broken or cut strands, broken wires, and
general corrosion. Why? Because wire rope will fail if worn out,
overloaded, misused, damaged, or improperly maintained. Let’s talk
about some of the indicators to look for:
• A permanent set or bend in a wire rope indicates damage.
Typically, you find this problem in rigging which wrap around the
load unlike the main or auxiliary hoist lines which only wrap
around the hoist drum, a sheave or hook block.
• Strands that stand proud of the rope or are loosely woven indicate
a problem. The protrusion of the core means that something has
shifted or loosened. Remove the rope from service.
• Look for any reduction in the rope’s diameter. It will stand out
when compared to the rope on either side. A reduction in
diameter typically indicates an overstressed section of the rope
which warrants an in-depth inspection.
• A shiny section of wire rope indicates that it has been rubbing
against something, which if not corrected, may cause a reduction
in the diameter of the outer wires that will lead to breakage.
Broken wires are a fact of life for wire rope.
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2. The ANSI standard for overhead cranes (ASME B30.2) allows for 12 broken
wires in any one lay or 4 broken wires in one strand in one lay or 4 broken wires
in one strand in one lay. A lay is the distance that it takes one strand to make a
full revolution around the core of the wire rope. The length of one lay is different
for each wire rope being determined by the rope’s diameter and construction.
• Discoloration of the wire rope indicates it has been exposed to heat. Should the
wire rope become part of an electrical ground path, as might be the case if
someone was arc welding on a load while hanging from the crane or exposed to
the flame of an oxy-acetylene torch, the exterior will take on a bluish hue. Our
concern is that the temperature may have been high enough to affect the
temper of the steel wires.
While there are many special purpose ropes, in general, fiber core wire rope should
not be used in areas with temperatures above 200°F. Ropes with independent wire
rope cores can be used at temperatures from minus 40°F to 400°F. For precise
information, check the manufacturer’s instructions.
The “nominal” or “catalog” strength applies only to a new, unused wire rope. ANSI
B30.2 calls for a design factor of 5. This means that the maximum load for a single
part of line is the nominal strength divided by 5 (design factor).
Try this for show and tell!
Take a small section of brand new wire rope and ask the group how to check for
broken wires while at the same time moving your bare hand up and down above
the wire rope – Be careful not to touch it! Make a point that this should never be
done on a working wire rope.
Use a shop rag or glove to demonstrate the correct way to check a wire rope for
broken wires. Wrap the rag or glove loosely around the wire rope and move it up or
down. A broken wire will “catch” and stop the rag. Make sure to turn the rope 180°
and repeat the process so that the entire diameter is checked.
Discuss methods that can be used to mark broken wires. And what should be done
after they are discovered.
Demonstrate the length of “one lay,” the distance for a strand to make one
revolution around the core.
Questions you can use to get them talking:
• Are there any areas of the shop/plant that have higher temperatures than
200°F? 400°F?
• Does “dragging” or “rubbing” a wire rope across a structural member damage
the rope?

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The illustrations, instructions and principles contained in the material are general in scope and, to the best of our
knowledge, current at the time of publication. No attempt has been made to interpret any referenced codes, standards or
regulations. Please refer to the appropriate code, standard or regulation making authority for interpretation or clarification.