The stranding factor
RoundTable – ENDURANCE RESEARCH OF WIRE ROPE AND ITS PRACTICAL APPLICATIONS – Glasgow 1985
The admissible static work load on a hauling rope will be determined by the calculated breaking load under consideration of the rope safety. Apart from the amount of static and dynamic stresses in hoisting plants, the stranding factor as a characteristic parameter for the construction and manufacture of a rope, affects the actually existing work load on the wires in the hauling rope and consequently the endurance limit of the rope, i.e. the total possible hoisting work of the rope up to the point, when it has to be discarded. An empirical investigation was carried out to determine the stranding factor of ropes of different constructions and diameters. The data thus obtained assert the mean value and range of variation of the stranding factor in dependence of the various rope characteristics. A mathematical model has been established for the calculation of the stranding factor. The results of this model of calculation are compared under statistical aspects with test results achieved with the same ropes. The results of such comparison altogether show that the stranding factor can relatively accurately be calculated from the rope configuration.
Author: G. Apel