How many randomly distributed broken wires in one lay are required to remove IWRC running rope from service?

How many randomly distributed broken wires in one lay are required to remove IWRC running rope from service?

• A. 4
• B. 6
• C. 8
• D. 10

Answer: (B)

The key idea is knowing when damage in a wire rope is severe enough to retire it. For running rope that uses an Independent Wire Rope Core (IWRC), the standard rule is that six broken wires in one lay, distributed randomly around the rope, means the rope must be removed from service. This threshold reflects that once six wires in a single lay are damaged in this way, the rope’s ability to safely carry load is significantly compromised, and the risk of sudden failure increases. If the broken wires were fewer than six and randomly distributed, the rope might still be considered serviceable, though it would warrant continued monitoring. Concentrated damage in one area is even more dangerous, but the rule specifically uses random distribution to identify when damage is widespread enough to retire the rope. Therefore, six is the correct threshold for IWRC running rope.

The key idea is knowing when damage in a wire rope is severe enough to retire it. For running rope that uses an Independent Wire Rope Core (IWRC), the standard rule is that six broken wires in one lay, distributed randomly around the rope, means the rope must be removed from service. This threshold reflects that once six wires in a single lay are damaged in this way, the rope’s ability to safely carry load is significantly compromised, and the risk of sudden failure increases.

If the broken wires were fewer than six and randomly distributed, the rope might still be considered serviceable, though it would warrant continued monitoring. Concentrated damage in one area is even more dangerous, but the rule specifically uses random distribution to identify when damage is widespread enough to retire the rope. Therefore, six is the correct threshold for IWRC running rope.