Crane Rope Spooling Tension: The Paint-Line Check

By Dean McDonald, founder, Crane Rope Solutions

Consistent tension is the holy grail of rope service life. Radial forces crush rope: the upper layers push down on the layers below. What really kills the rope is those radial forces combined with the micro-movements the rope makes as it stretches and relaxes through loading and unloading.

The paint-line check

Pay the rope off down to the safety wraps.
Tension the rope to 5 to 10% of its minimum breaking load, or as the crane manufacturer recommends.
Spool on the first layer under tension, then paint a straight line across the drum.
Pull the rope back off, re-tension it and spool it back on. If the line is no longer straight, the tension was not equal.
If the line is straight, spool on the next layer and repeat through the remaining layers.

As long as daily checks are made, you can always monitor tension and re-tension the rope if necessary.

From our inspections

Slack, loosely wound rope on both winch drums of a Tadano GR-1000XL rough-terrain crane — **Tadano GR-1000XL rough-terrain crane, winch ropes**Rope diving and distortion from loose wraps, after the rope was reeved with more parts of line than the lift needed.

Loose, uneven wraps of 19 mm hoist rope on a Tadano GR-1600XL winch drum — **Tadano GR-1600XL rough-terrain crane, 19 mm hoist rope**Loose, uneven wraps of 19 mm hoist rope on the winch drum.

Gaps and irregular wraps in the winch 4 rope layers on a Liebherr LG 1750 drum — **Liebherr LG 1750, winch 4 rope**Gaps and irregular wraps in the rope layers on the winch 4 drum.

Hoist rope drum of a Liebherr 280 HC-L luffing tower crane, marked for hoist rope tension — **Liebherr 280 HC-L luffing tower crane**Marking hoist rope tension on the hoist drum.

More wire rope damage photos

Need a replacement rope? Find your crane for the diameter, length and part number of every winch, or call 604-813-9473.

Consistent tension: the paint-line check for multi-layer drums

The paint-line check

From our inspections