Wire Rope Inspection and Replacement Criteria Flashcards

A wire rope operating on a crane hoist drum shows 4 broken wires in one rope lay and 7 broken wires in 10 rope diameters, all located within a single strand. Under ASME B30.2 criteria, what is the correct course of action?

Answer: Remove from service only because the 10-diameter criterion (6 broken wires) is exceeded; the per-lay count is acceptable

Under ASME B30.2, a rope must be removed if there are 6 or more broken wires in 10 rope diameters, regardless of the per-lay count. Here, 7 broken wires in 10 diameters exceeds that threshold, triggering immediate removal. The per-lay count of 4 (limit is typically 12 for 6×19 classification) does not independently require removal, but the 10-diameter criterion alone is sufficient cause.

During inspection of a 6×37 classification wire rope, you find a valley break (interstrand nicking) between two adjacent strands with no visible broken outer wires. What does this condition indicate and how should it be addressed?

Answer: Valley breaks indicate internal wire breakage from fatigue or contact stress between strands, and the rope must be removed from service regardless of visible outer wire condition

Valley breaks (interstrand nicking) occur at the contact points between adjacent strands and indicate internal wire fractures caused by fatigue or contact stress — damage that is not visible as conventional surface wire breaks. ASME B30.2 and industry standards treat any valley break as cause for immediate removal from service because internal wire failures cannot be quantified by external visual inspection and signal accelerated fatigue progression.

A running wire rope exhibits a 'birdcage' (basket distortion) deformation over a 6-inch section after being shock-loaded. The outer strands appear to have returned nearly to their original position after the load was released. What is the correct action?

Answer: Remove from service — birdcaging permanently damages the rope's internal geometry and load-sharing even if the strands appear to have returned to position

Birdcaging causes the outer strands to elongate relative to the core, permanently disrupting the internal load-distribution geometry of the rope. Even if the visible distortion partially rebounds, the wires and strands no longer bear load in their original helical paths. The rope has lost its ability to distribute loads evenly among all wires, meaning it can fail catastrophically at a fraction of its rated capacity. ASME B30.2 requires immediate removal from service for any rope exhibiting birdcaging.

You are inspecting a wire rope operating over a sheave and notice the rope diameter has decreased by 3% from its nominal diameter, but no broken wires are found and lubrication appears adequate. The rope is a 6×19 IWRC (Independent Wire Rope Core). What is the most likely cause and correct action?

Answer: The diameter reduction indicates core failure or severe internal wire breakage — remove from service immediately per ASME B30.2 criteria for diameter reduction

ASME B30.2 specifies rope removal when nominal diameter has decreased by 3% or more for 6×7 and 6×19 classification ropes (and 1/64 inch or more for smaller diameters, whichever is less restrictive). A 3% reduction — even without visible broken wires — is significant because it typically indicates core deterioration, internal wire breaks, or severe loss of lay, all of which drastically reduce the rope's capacity. The IWRC designation does not raise this threshold; the 3% limit applies regardless of core type.

A wire rope on a mobile crane boom hoist has been in service for 18 months. During a periodic inspection, the inspector finds kinking at the point where the rope leaves the drum, corroded pitting on 3 outer wires (no wire breaks), and a section of rope that passed through a sheave showing a wave (sinusoidal) distortion. Which condition alone is an unambiguous, stand-alone criterion for immediate removal under ASME B30.2?

Answer: Kinking at the drum departure point

Kinking is explicitly listed in ASME B30.2 as a stand-alone condition requiring immediate removal from service, because kinking permanently damages the rope's helical geometry and creates a stress concentration that cannot be corrected. Wave/sinusoidal distortion is also a removal criterion, but the question targets the condition that is most unambiguously and categorically listed. Corroded pitting without wire breaks is evaluated for severity and may not alone trigger removal. Service age alone is not a removal criterion under ASME B30.2 — condition governs.

During an inspection of a wire rope used on a personnel hoisting application, a competent person finds 5 broken wires in one rope lay of a 6×19 classification rope with a fiber core. The breaks are randomly distributed across multiple strands. Under ASME B30.23 (personnel hoisting), how does the removal threshold differ from standard ASME B30.2 crane applications?

Answer: ASME B30.23 applies a more conservative threshold of 2 broken wires in one lay for personnel hoisting, requiring immediate removal

Personnel hoisting under ASME B30.23 applies far more stringent wire rope criteria than standard crane service. For personnel hoisting, the broken wire removal threshold is 2 broken wires in one rope lay — compared to 12 in one lay for 6×19 classification ropes in standard crane service under ASME B30.2. With 5 broken wires in one lay, this rope exceeds the personnel hoisting threshold by a factor of 2.5 and must be immediately removed from service. The heightened standard reflects the life-safety criticality of personnel hoisting.