Dynamic contact and slip characteristics of bent hoisting rope in coal mine

Abstract

Dynamic contact and slip characteristics of bent hoisting rope in coal mine were investigated in this study. Dynamic tensions of hoisting rope bending around friction lining at distinct arc locations were obtained employing hoisting dynamics and friction transmission theories. The finite element model of contacting bent rope and friction lining was established to explore dynamic contact characteristics and relative slip amplitudes between the rope and friction lining, and between contacting strands in the rope, respectively. The results show that dynamic tensions of bent rope at distinct arc locations are related to slip and inactive slip states of rope segments. Higher stress concentrations are present at contacting locations between adjacent strands and between the rope and friction lining at every central angle at any lifting time. An increase of central angle φ causes overall increased equivalent von Mises stress distributions on the rope cross-section and near contacting locations within the slip angle between the rope and friction lining as compared to constant equivalent stress distributions within the inactive slip angle. Relative slips are induced by differences between tensions of bent rope segment at both sides within the slip angle as compared to no relative slip within the inactive slip angle, which is the same in cases of contacting rope and friction lining, and neighboring strands.