Wire rope announces its retirement in advance — broken wires, diameter loss, and deformation all appear before failure. The inspector's job is knowing where to look and what counts. Here are the criteria from ASME B30 practice, in field language.
The Two Inspection Levels
Frequent (each shift/use, by the operator): visual scan of the working length for obvious damage, kinks, and broken wires. Periodic (documented, by a designated inspector, at intervals set by service severity): full-length inspection with diameter measurements, records kept per rope.
Broken Wire Limits
| Application | Removal criteria |
|---|---|
| Running ropes (hoists, cranes) | 6 randomly distributed broken wires in one lay, or 3 in one strand in one lay |
| Slings | 10 in one lay, or 5 in one strand in one lay |
| Rotation-resistant ropes | 2 in 6×d, or 4 in 30×d |
| Any valley breaks | 1 valley break = remove |
| At end terminations | 2 broken wires = remove or re-terminate |
Flex the rope over a bar to expose hidden breaks; run a cloth to catch fishhooks.
Diameter & Deformation
Measure across the crowns with a caliper and compare to nominal: reduction to 1/32" under nominal (small ropes) or per the crane manufacturer's limit means retirement — diameter loss signals core failure or internal wear. Retire immediately for kinks (birdcages, popped cores, doglegs), crushing, flattening over drum crossovers, and any heat damage: arc strikes and torch contact make rope scrap on the spot.
Corrosion & Lubrication
Pitting corrosion — especially internal, revealed by opening the lay slightly — is retirement; surface rust with intact wires calls for cleaning and re-lubrication. Field lube should penetrate (thin, then film), applied at a bend where strands open. A dry rope wears from the inside invisibly; lubrication is inspection's partner, not an afterthought.
Records That Hold Up
Per-rope file: installation date, construction and cert, periodic inspection dates, measurements, and findings. When an incident review asks for it, this file is what stands between a program and a citation.
Replacement Rope & Slings, Certified
Wire rope, slings, and hoist rope with certs, cut and terminated in-house. Put construction, diameter, and length into the quote form at the top of the page — quotes answered during business hours.