Servicing Wire Ropes

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CRITERIA FOR INSPECTING AND DISCARDING WIRE ROPES

Structure of wire ropes

Standard Ropes and Heavy-Duty Ropes.

Rotation Resistant Ropes

The lay of strands (wire rope) can be twisted either to the left or to the right. To determine whether the lay is left or right handed, look along the rope and see whether the wires appear to turn anti-clockwise (let handed) or clockwise (right handed) as they get further away from you.

Discard Criteria

Note: Regular rope inspection and maintenance shall be carried out according to the guideline instructions provided by the manufacturer and according to international standard ISO 4309:2017^[1].

Note: Mechanical and electrical maintenance work requires special skills and tools to ensure safe and reliable operation of the product. Maintenance work shall be carried out only by authorized service personnel or an experienced service technician authorized by the product's manufacturer or manufacturer's representative.

Note: The internal examination of wire rope shall not be done as part of regular maintenance, unless the person is trained for that examination (ISO4309 Annex D).

Local reduction of rope diameter

A reduction in the rope diameter in any part of the rope is an indication of internal or external wear or damage.

To accurately measure the diameter at any point of the rope, rotate the vernier caliper around the rope to record the maximum dimension.

Local increase of rope diameter

An increase in rope diameter in any part of the rope is an indication of deformation inside the rope.

Basket (birdcage) deformation

Basket (birdcage) deformation occurs when there is a difference in length between the rope core and outer strands.

Protrusion of rope parts

Bends

Bends and other angular deformations in ropes are normally caused by external influences.

Mild bends can often be removed by carefully bending the rope by hand to straighten out the bend.