Demands for longer operation life and higher breaking loads have contributed to the development of "special wire ropes". These are to be used in demanding and tough environments when the ropes are used intensively.
The special wire ropes are often manufactured with high tensile wires and the strands are in many cases compacted to give a larger steel area and consequently a higher breaking load. This results in an increased working load for a specific rope diameter. Compacting of the rope also results in longer life and therefore a lower life cost.
Some areas of use demand wire ropes with better stability and extra low inner friction. For that purpose ropes are manufactured with a plastic coated steel core.
Special wire ropes can be double parallel which means that both wires and strands lay parallel to each other. This prevents wire cross over which can lead to wire indentations. Special wire ropes have a few things in common: less outer and inner friction, narrow tolerances, more flexible, more rounded and a larger contact surface against sheaves and drums. This results in a longer life in tough working conditions.