Dynamic simulation and experimental investigation of the double-rope winding hoister based on an equivalent mechanical model of wire ropes

Accurate and efficient dynamic analysis is essential for the reliable operation and optimal design of the wire rope hoisters. However, traditional 3D finite element (FE) methods require a significant amount of time for long and geometrically complex steel wire ropes that makes it impossible to predict dynamic performances of wire rope winding hoisters. For this problem, an equivalent mechanical modeling method for different wire ropes is proposed in this work. Based on this method, an equivalent mechanical model (EMM) is established for a circular arc wire rope with a fan-shaped strand cross section and verified by experimental tests. It is also validated that this EMM has the capability of characterizing mechanical behaviors of tension, torsion and bending deformations of the wire rope at the same time. Base on the EMM, a full-size 3D FE model of the double-rope winding hoister is established for the first time to investigate its dynamic performances during the lifting processes under a long-distance, high-speed, heave-load condition. Apart from the coupling axial and lateral vibrations and dynamic tension fluctuations of the wire ropes, the multi-layer winding process of ropes and the interaction between the ropes and the drums and sheaves as well as the rope itself are captured by this FE model against the traditional theoretical method. The accuracy of the FE model is finally verified by an experimental test using a double rope winding hoister test prototype. The method proposed in this work can contribute to the early design and analysis of wire rope drive hoisters.