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STEEL WIRE ROPE
CONSTRUCTION The number of strands and wires will influence the flexibility, fatigue and wear resistance of any given wire rope. Rope selection is often a compromise. Generally the more load bearing wires in the rope the greater the flexibility, however the smaller the wires the less abrasion resistance. For example, the same nominal diameter 7 x 7 wire would be less flexible than a 7 x 19 wire, hence a large number of small size wire and strands produce a flexible rope with good resistance to bending fatigue wear. The construction of wire rope is defined by the number of outer strands (first number), and the number of wires within that strand (second number) and then by the arrangement of the wires in each strand (shown in brackets). The wires in each strand can be arranged in several ways, for example a 6 x 19 construction the 19 wires in each strand are laid 6 around 1 centre wire.
6 X 19 Fibre Core Wire
7 X 7 Steel Core Wire
7 X 19 Steel Core Wire
CORE The core of a steel wire rope serves as a foundation for the strands, providing stability by keeping them in place throughout the life of the rope. Wire ropes can be supplied with either a fibre or wire rope core.
GRADE Wire rope can be supplied in several different grades. The grade of wire rope affects the ultimate breaking strength of the wire rope but will also influence the life of the rope. The higher the grade, the higher the minimum breaking strength. Common grades that are available include 1570,1770, 1960, 2070 and 2160.
FINISH Wire Ropes can be supplied as Black (self-colour), Galvanized or Stainless Steel.
Wire rope is lubricated at time of manufacture, this helps reduce friction between wires and strands, and the friction between the rope and drum or sheave. In addition the lubrication retards corrosion and inhibits possible rotting of the fibre core.
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MATERIALS HANDLING TECHNICAL MANUAL | VOL. 4
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