Rope Technology

Rope End-Connections

Points of reference to determine the rope length precisely

For some rope applications, e.g. pendant ropes, the rope length is essential. The following terms are used to describe the points of reference that are important to determine the rope length precisely. Some typical examples are added.

By using the terms we want to make sure that both of us avoid mistakes. Besides the points of reference also the force, the length is applied to, needs to be determined by you also. Without any information the force, the length is applied to, is agreed to be F=0kN.

Efficiency factor KT of rope end-fittings

The minimum-breaking load given in the data sheet is “…specified value in kN, below which the measured breaking force (Fm) is not allowed to fall in a prescribed breaking force test…” (according to DIN EN 12385-2, 3.10.10). In particular for the crane designer it is important to know which influence a chosen end-ftting has on the transferable breaking strength of the ropeend- fitting system. The minimum test strength that should be reached when examining a rope end-fitting in a pull test, is determined with regard to the minimum breaking strength and considering the efficiency factor KT.

KT = 0,9 means, the test strength that has to be achieved must be at least 90% of the minimum breaking force of the rope. Unless otherwise indicated, the following basic rules apply: KT = 1,0 for casted rope end-fittings KT = 0,9 for pressed rope end-fittings