Wire rope is a type of cable which consists of several strands of metal wire laid (twisted) into a helix. The term cable is often used interchangeably with wire rope. However, in general, "wire rope" refers to diameter larger than 3/8 inch (9.52 mm). Sizes smaller than this are designated cable or cords.[1] Initially wrought iron wires were used, but today steel is the main material used for wire ropes.
Historically wire rope evolved from wrought iron chains, which had a record of mechanical failure. While flaws in chain links or solid steel bars can lead to catastrophic failure, flaws in the wires making up a steel cable are less critical as the other wires easily take up the load. Friction between the individual wires and strands, as a consequence of their twist, further compensates for any flaws.
Wire ropes were developed starting with mining hoist applications in the 1830s. Wire ropes are used dynamically for lifting and hoisting in cranes and elevators, and for transmission of mechanical power. Wire rope is also used to transmit force in mechanisms, such as a Bowden cable or the control surfaces of an airplane connected to levers and pedals in the cockpit. Static wire ropes are used to support structures such as suspension bridges or as guy wires to support towers. An aerial tramway relies on wire rope to support and move cargo overhead.
Wires
Steel wires for wire ropes are normally made of non-alloy carbon steel with a carbon content of 0.4 to 0.95%. The very high strength of the rope wires enables wire ropes to support large tensile forces and to run over sheaves with relatively small diameters.
Strands
In the so-called cross lay strands, the wires of the different layers cross each other. In the mostly used parallel lay strands, the lay length of all the wire layers is equal and the wires of any two superimposed layers are parallel, resulting in linear contact. The wire of the outer layer is supported by two wires of the inner layer. These wires are neighbours along the whole length of the strand. Parallel lay strands are made in one operation. The endurance of wire ropes with this kind of strand is always much greater than of those (seldom used) with cross lay strands. Parallel lay strands with two wire layers have the construction Filler, Seale or Warrington.
Spiral ropes
In principle, spiral ropes are round strands as they have an assembly of layers of wires laid helically over a centre with at least one layer of wires being laid in the opposite direction to that of the outer layer. Spiral ropes can be dimensioned in such a way that they are non-rotating which means that under tension the rope torque is nearly zero. The open spiral rope consists only of round wires. The half-locked coil rope and the full-locked coil rope always have a centre made of round wires. The locked coil ropes have one or more outer layers of profile wires. They have the advantage that their construction prevents the penetration of dirt and water to a greater extent and it also protects them from loss of lubricant. In addition, they have one further very important advantage as the ends of a broken outer wire cannot leave the rope if it has the proper dimensions.
ORDERING INFORMATION AS BELOW: (to save your time)
1.Application: For which rope will be used.
2.Size: Diameter of the rope in millimeter or inches.
3.Construction: Number of strands, number of wires per strand and type of strand construction.
4.Type of Core: Fiber core(FC), independent wire rope core(IWRC) or independent wire strand core(IWSC).
5.Lay: Right regular lay,left regular lay,right lang lay,left lang lay.
6.Lubrication:Preformed or not.
7.Material: Bright(un-galvanized),galvanized or stainless steel
8.Grade of wire: Tensile strength of wires
9.Breaking Load: Minium or calculated breaking load in tones or pounds.
10.Length: Length of wire rope.
11.Packing: In coils wrapped with oil paper and hessian(orp.p)cloth, or on wooden reels.
12.Quantity: By number of coils or reels,by length or weight
13.Specification: Any recognized specification, if necessary.
14.Certification: Mill sheet and/or a third party's inspection,if necessary.
15.Remarks: Shipping marks and any other special requirements.
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