What is Wire rope?
[[Image:Steel wire rope.png|thumb|Steel wire rope (right hand lay)]] [[Image:6x19 wire rope construction-en.svg|thumb|Wire rope construction]] [[Image:Fraying wire rope.jpg|thumb|This image of a fraying wire rope shows some individual wires.]] [[Image:Wire rope with thimble and ferrule.jpg|thumb|500px|RHOL wire rope terminated in a loop with a thimble and ferrule]] '''Wire rope''' consists of several strands laid (or 'twisted') together like a helix. Each strand is likewise made of metal [[wire]]s laid together like a [[helix]]. Initially [[wrought iron]] wires were used, but today [[steel]] is the main material used for wire ropes. ==History & materials== Modern wire rope was invented by the German [[mining]] engineer [[Wilhelm Albert]] in the years between 1831 and 1834 for use in mining in the [[Harz Rural District|Harz]] Mountains in [[Clausthal]], [[Lower Saxony]], [[Germany]]. It was quickly accepted because it was better than ropes made of hemp or to metal [[Link chain|chain]]s, such as had been used before. Wilhelm Albert's first ropes consisted of wires twisted about a [[hemp]] rope core, six such strands then being twisted around another hemp rope core in alternating directions for extra stability. Earlier forms of wire rope had been made by covering a bundle of wires with hemp. In America wire rope was later manufactured by [[John A. Roebling]], forming the basis for his success in [[suspension bridge]] building. Roebling introduced a number of innovations in the design, materials and manufacture of wire rope. Manufacturing a wire rope is similar to making one from natural fibres. The individual wires are first twisted into a strand, then six or so such strands again twisted around a core. This core may consist of steel, but also of natural fibres such as [[sisal]], [[manila hemp|manila]], [[henequen]], [[jute]], or hemp. This is used to cushion off stress forces when bending the rope. ==Construction & specification== The specification of a wire rope type, including the number of wires per strand,