A Machine for Interactive Fatigue Testing of Wire Rope

Fatigue damage to multi-strand ropes has led to a number of failures at the jib tip sheave. The mechanism which causes the damage (termed bending-tension fatigue) is a combination of small amplitude bending in phase with fluctuating tension (caused by dynamic snatch loading of the rope) exacerbated here by corrosion. The testing machine designed and manufactured allows the independent control of all the major parameters which determine the bending-tension fatigue endurance. The design includes provision for fatigue testing of the rope whilst sprayed or submerged in salt water to include the effect of a corrosive environment. This requirement has had a fundamental influence upon the final design.

Author(s):  I.M.L. Ridge & C.R. Chaplin