By Colin Rice
It is essential that well-defined usage, inspection and discard standards are developed for wire ropes used in the drilling industry and that these standards are applied to ensure that we fully comply not only with legal requirements but also with our common law duty.
This is the third article of Part 2 of our Technical Series on Wire Rope Safety. Click here for an outline of the entire Technical Series on Wire Rope.
It is recommended that the following simple standards are used as a basis for hoist rope discard in exploration drilling operations.
Hoist ropes shall be discarded if one or more of the following conditions are detected:
1. Three or more broken wires are found in close proximity to a rope termination.
2. Three or more broken wires are found in one strand.
3. Rope diameter anywhere is reduced to 90% of the nominal diameter.
4. A wave, birdcage, knot, loop, kink, localised flattening or any other defect is detected.
5. Any indication of any internal wire breaks will be a reason for immediate discard of the rope.