Maintenance of Wire Rope

To maximize the service life of wire ropes, personnel should perform regular maintenance and care. Periodic maintenance is a critical measure for extending their operational lifespan and ensuring workplace safety. Wire ropes are subjected to substantial stresses duRing Lifting, pulling, and hoisting operations, inevitably leading to wear, corrosion, and fatigue. The primary aspects of maintenance and key steps for preservation are as follows:

Wire Rope Maintenance

Maintenance of wire ropes shall be performed based on the type of crane, frequency of use, environmental conditions, and wire rope specifications. Throughout the service life of the rope, and before signs of drying or corrosion appear, periodic lubrication shall be carried out as directed by competent personnel—particularly in sections passing over sheaves and drums, as well as areas interacting with equalizer sheaves. To enhance lubrication efficacy, cleaning the wire rope prior to lubrication may be necessary.

The lubricant used for wire ropes shall be compatible with the original lubricant applied by the wire rope manufacturer and possess penetrating properties. If the type of lubricant cannot be determined from the crane operation manual, the user should consult the wire rope supplier or manufacturer.

Inadequate maintenance of wire ropes will adversely affect service life, particularly when cranes or hoists operate in corrosive environments or where lubrication is not feasible. Under such conditions, the inspection intervals for wire ropes shall be shortened accordingly.

When protruding broken wires at a specific section of A Wire Rope pass over sheaves, they may be pressed against adjacent areas, causing localized deterioration. To mitigate this risk, prominently protruding broken wires should be removed by clamping the exposed end and repeatedly bending it until it fractures (this typically occurs in the strand valleys). During maintenance, the location of any removed broken wires should be documented and provided to wire rope inspection personnel. Each removed broken wire shall be counted as a single broken wire and must be considered in the evaluation of the rope’s condition against rejection criteria based on broken wire counts.

If broken wires are concentrated near or at the termination point of the wire rope, and the remaining sections along the rope length remain unaffected, the rope may be shortened and the end termination reassembled. Prior to this operation, the remaining length of the rope must be verified to ensure that the minimum number of wraps required on the drum is maintained when the crane operates at its extreme working positions.

Maintenance of Crane Components Related to Wire Ropes

In addition to the maintenance instructions provided in the crane operation manual, drums and sheaves should be inspected periodically to ensure they rotate freely on their bearings. Note: A sheave that fails to rotate freely or exhibits severe and uneven wear of its rolling elements will cause accelerated wear of the wire rope. An equalizing sheave that no longer functions properly may lead to load imbalance in the rope reeving system.

Key Maintenance Procedures

1. The service life of a wire rope is highly dependent on its operating conditions. It must be used in strict compliance with regulations: dragging or throwing is prohibited; overloads must be avoided; sharp bends shall not be induced; abrupt changes in lifting or lowering speed are not permitted; and shock loads shall be prevented.

2. When rust or dirt accumulates on the wire rope, remove it with a steel wire brush and apply lubricant promptly.

3. Lubricate the wire rope every four months. Optimal lubrication involves applying heated oil (approximately 50°C) to allow penetration into the core, followed by wiping off excess lubricant.

4. After coiling, the wire rope shall be stored in a clean, dry area. Improper stacking that may cause twisting or deformation is prohibited.

5. Secure the rope ends by binding with steel wire, sealing with low-melting-point alloy, or fastening with a ferrule to prevent strand loosening.

6. If oil extrusion is observed on the rope surface during operation, it indicates excessive loading. Immediately stop increasing the load, inspect the rope thoroughly, and replace it if necessary.