HOW AN ADDITIONAL TRACTION SHEAVE REDUCES FATIGUE OF WIRE ROPES IN MULTI-LAYER APPLICATIONS THROUGH CONTROLLING THE SPOOLING TENSION

Summary

Mobile, crawler and tower cranes commonly utilise multi-layer spooling drum winches. This amounts to drastically reduced wire rope service life. During operation, changing loads result in an uneven pressure distribution inside the spooling package. This produces local peaks in pressure and relative movement between rope layers, both of which cause increased wear. In this article, we present a novel tension control hoist that reduces negative influence from multi-layer spooling by eliminating variations in rope tension on the spooling package. An additional traction sheave that runs in conjunction with the drum through a torque-drive-control disconnects the lifting load from the rope tension on the drum. Spooling experiments show an increase in service life and lifetime of 85% and 39%. Keywords: wire rope, drum winch, multi-layer spooling, fatigue, experimental analysis

Author(s): R. Hofmann, T. Schmidt