General Rope Characteristics


Each rope is first of all characterized by its nominal diameter, from which the actual diameter is estimated depending on regulations, application type and specific customer requests. 


The actual diameter of wire rope changes during use due to initial rope stabilization, the effect of working tension, and wear caused by passage over components of the reeving system.

To ensure good rope performance when operating on grooved drums, the actual diameter has to comply with the oversize of the groove. Typical diameter tolerance is +2% / +4%. This value is very common for heavy lifting applications, and will be the reference value for the information contained in this catalogue, however it can be adapted on the basis of specific customer requirements.

Lay direction is selected to confer unique characteristics to the product: when spooled over drums, Lang’s lay ropes ensure better stability to side wear (a phenomenon also known as “crushing”) as the contacts between the wires of rope wraps are smoother than in regular lay construction. On the other hand, regular lay improves rotation stability and is therefore recommended for ropes having a diameter greater than 40mm, used for high lifting heights or deployment into deep sea situations.

Lay length is also selected in accordance with specific requirements: longer lay improves load capacity, Young modulus and consequently axial stiffness, whereas shorter lay gives better resistance to shock loading.

Ropes for heavy lifting activities require a high load efficiency and are typically composed of compacted strands, obtained by means of dies or roller devices during manufacture.

High compacting level allows an improvement in the metallic area of up to 15% with respect to conventional strands, and also leads to smoother surface contact, dimensional stability in respect to side pressure, resistance to wear and abrasion, and better spooling capacity.

In case of reeving arrangements involving a relatively high fleet angle between adjacent components (from 2° to 4°), plastic impregnated core ropes can be adopted to enhance rope stability.






Lay direction: The direction right (Z or RH) or left (S or LH) corresponding to the direction of lay of the outer strands in a stranded rope in relation to the longitudinal axis of the rope.

Ordinary lay (or regular): Stranded rope in which the direction of lay of the wires in the outer strands is in the opposite direction to the lay of the outer strands in the rope (RL).

Lang lay: Stranded rope in which the lay direction of the wires in the outer strands is in the same lay direction as that of the outer strands in the rope (LL).

Rope lay length (H): That distance (H) parallel to the longitudinal rope axis in which the outer wires of a spiral rope, the outer strands of a stranded rope or the unit ropes of a cable-laid rope make one complete turn (or helix) about the axis of the rope.