Detection and quantitative characterization of external and internal broken wire clusters and corrosion pitting in wire ropes

Modern wire ropes have a tendency to deteriorate internally, which makes visual inspections ineffective. Furthermore, several categories of potentially serious rope deterioration, such as external and internal fatigue breaks, corrosion pitting and fretting, usually cause little or no loss of metallic cross-sectional area (LMA). Thus, major reductions of the remaining strength of a rope are often associated with only a small LMA. In other words, LMA alone is frequently not a reliable indicator of rope degradation, and the custom of using LMA as the sole rope retirement criterion can be dangerous and is suspect. The present paper introduces a new inspection and analysis method that promises to improve this situation. Test results from several well-documented rope samples confirm the feasibility and accuracy of the new approach.

Author: H.R. Weischedel