How to install wire rope clips

A clip termination is only as good as the way it was fitted. Most failures trace back to four things: the saddle on the wrong side of the rope, too few clips, the wrong spacing, or nuts that were never re-tightened after the first load.

1. Check that the clip size matches the rope diameter exactly, and that the rope is not damaged, kinked or badly corroded where the clips will sit.
2. Form the eye. If a thimble is used, seat the rope in it — the thimble stops the rope wearing at the point where it bears on the shackle or pin.
3. Fit the first clip one saddle width back from the end of the dead end, with the saddle on the live part and the U-bolt on the dead end. Tighten the nuts evenly but not yet to full torque.
4. Fit the second clip as close to the thimble as possible, in the same orientation.
5. Fit the remaining clips between the first two, spaced evenly. Spacing between clips is generally 1.5 to 3 times the clip width. Do not place them at random intervals.
6. Apply light tension to the rope, then tighten all nuts evenly, alternating between them, up to the specified torque.
7. Tighten again to the specified torque before the assembly goes into service.
8. After the first load has been applied, re-check the torque and correct it. Rope strands settle under the first load and the nuts lose tension.

• Published guidance ties re-tightening to duty cycles: around 10,000 cycles for heavy use, 20,000 for moderate use and 50,000 for light use.
• When the cycle count is not known, a competent person sets a period instead — commonly three, six or twelve months depending on the duty.
• Regardless of interval, re-check the torque after the first load and after any event that could have disturbed the assembly.

• Saddle on the dead end. The U-bolt bears on the live rope, crushes the outer wires and the termination loses a large part of its holding power.
• Too few clips, or clips spaced at random rather than evenly between the first two.
• Under-torqued nuts — the rope slips through; over-torqued nuts — the thread or the clip body is damaged. Use a torque wrench.
• No re-tightening after the first load.
• Using a light malleable clip where a forged clip is required, or using a clip size that does not match the rope.
• Using U-bolt clips as a permanent lifting termination. Standard-pattern clip terminations to EN 13411-5 are intended for static loads and a single lift; a sling for repeated lifting uses a swaged or spliced termination instead.
• Using U-bolt clips on coated rope without stripping the coating under the clips, or on applications such as mine hoist ropes and personnel lifting where they are prohibited.

Most catalogues list a single set of figures for a rope diameter without saying which type of clip it refers to. Under this standard there are two, and they differ substantially.