CORDAGE INSTITUTE FIBER ROPE EXTERNAL ABRASION TEST GUIDELINE

Summary

This paper discusses the new Cordage Institute (CI) guideline for external rope abrasion tests using a rotating abrasive wheel. [1] It includes concepts and findings which were not included in the previous OIPEEC paper “Guidelines for Rotating Wheel External Rope Abrasion Testing”. [2] This test demonstrates the ability of a rope to withstand external abrasion damage. Other abrasion test methods, which subject the rope to cyclic bending, can cause other forms of internal and external rope damage. The test employs an abrasion test carriage that contains two wheels which guide the rope and an abrasion wheel which rotates against the rope. This carriage is mounted on the bed of a rope tension test machine. During the test, a constant tension is applied to the rope. The test can continue until the rope fails. Or, it can apply a defined number of revolutions, after which the rope is examined to quantify damage and broken to determine residual strength. The new CI guideline describes the test equipment and the general test method, but the abradant material and other test details appropriate for a particular application are left to the user to specify. The equations for designing a test are derived in an appendix to the guideline. Other guideline appendices discuss abradant material considerations and the mechanics of rope external abrasion. The CI guideline is intended to be used in preparing a standard or specification appropriate for a particular rope type and service use. This paper is of interest to fiber rope test engineers, manufacturers and users.

Author(s): J. Flory