Quantitative effects of twist initiators in ropeways and actual findings on fatigue of twisted Lang’s lay ropes

Subsequent to a project-introduction on “Digital measurement of rope rotation” at the OIPEEC conference in Stuttgart in 2015, a publicly funded two-year research project started dealing with twist initiators, their quantitative effects and the fatigue-life of twisted ropeway-ropes. This paper presents the current position of the three focal points of research: - Bending tests of twisted Lang’s lay ropes generating additional lifetime factors for Feyrer’s formula - Theoretical investigation into the number of influences of mechanical twist initiators, using Failure Mode and Effect Analysis (FMEA) of relevant parameters, comparison of rotation theory with measurements on ropeways with the rotation sensor-system - Lay length analysis by filtered Magnetic Rope Tests (MRT) of almost discarded hauling ropes identifying the storage of twist in jigback tramways. The results will be combined into a model allowing the prediction of rotation and twist storage in terms of design parameters, as well as to quantify the effects on rope lifetime. An approach will be made to transfer relevant findings onto other rope drives.

Author(s): K. Kuehner and K.-H. Wehking