On the origin of heat build-up in polyester ropes

At the Akzo Nobel laboratories the problem of heat generation in polyester mooring lines for floating units was addressed. Measurements of the loss factor tan δ were performed on single filaments, yarns and ropes. From these data the significance of interfiber friction in ropes could be determined. The friction was found to be of less importance as the hysteresis loss of the material itself. Other than is commonly assumed, loading conditions have a marked influence on hysteresis. By the performance of measurements over a wide range of loads and comparing of data for filaments, yarn and rope, the limits of safe use of polyester in practice could be estimated