A STUDY OF THE DECAY ZONE LENGTH AND COURSE OF THE DEFECT INFLUENCE OF THE DOUBLY TWISTED STEEL ROPES

Introduction

The determination of the defects along a certain rope section is not equivalent with the evaluation of its actual weakening. This is due to the so called decay zone of the influence on the weakening caused by the wire break /called further the attenuation zone/. The length of this zone is measured by the distance from the place of the wire break to the place where the broken wire takes over the full load shared normally by the wire from the distribution of the rope load. The occurrence of the attenuation zone is connected with the friction between wires. The friction forces, being the result of twisting the wires into strands and strands into the rope, with the interaction of the external load, produce a rise in the load taken over by broken wire with the growing distance from the wire break place. The influence of the length of the attenuation zone on the value of the actual weakening of the rope can be represented by the graph [_1] in fig. 1.