Electromagnetic inspection of wire ropes and strands on guyed and supported structures

Many guyed and wire rope or strand-supported structures in U.S. and overseas refineries, pipelines, and chemical plants were erected from 1950 through the 1970s, and some even earlier. While many of the components of these structures have been routinely inspected, the supporting wire rope and strand has typically been taken for granted, and only elementary visual inspections have been performed. Wire rope and strands in sedentary environments deteriorate and lose their working capability as a result of both internal and external factors. This article describes deterioration factors, the method used to detect corrosion, broken wires, abrasion, instrumentation operation, and use of the data to estimate remaining strength. Procedures for the inspection of guy ropes, strands, and their related fittings are covered, as are criteria for rope retirement.