How many broken wires must be present on one strand for one lay of running rope to be removed from service?

How many broken wires must be present on one strand for one lay of running rope to be removed from service?

• A. 2
• B. 3
• C. 4
• D. 5

Answer: (B)

The rule being tested is about when damaged wire rope must be taken out of service due to broken wires in a single strand within a single lay. For running rope, if there are three broken wires in the same strand within one lay, the rope must be removed from service. This threshold targets a localized defect that compromises the rope’s fatigue strength and can lead to a sudden rope failure under load. The idea of a lay length helps inspectors focus on a specific portion of the rope—one lay is the length corresponding to one complete twist of the strands around the rope’s core—so counting broken wires within that window assesses a real, localized weakness rather than dispersed damage.

The rule being tested is about when damaged wire rope must be taken out of service due to broken wires in a single strand within a single lay. For running rope, if there are three broken wires in the same strand within one lay, the rope must be removed from service. This threshold targets a localized defect that compromises the rope’s fatigue strength and can lead to a sudden rope failure under load. The idea of a lay length helps inspectors focus on a specific portion of the rope—one lay is the length corresponding to one complete twist of the strands around the rope’s core—so counting broken wires within that window assesses a real, localized weakness rather than dispersed damage.