Introduced the relevant point contact wire rope
2014-10-10
Strands of adjacent layer of steel wire is point contact state of wire rope, also called non parallel rope (Figure 1). The strandsof the steel wire rope (except the center wire) are all made of the same specifications of steel wire twisted system, each layer of steel wire twisting angles are equal but lay pitch range, is a wire rope for old structure, usually called the common round strand wire rope to belong to this kind of. Strand steel wire is arrangedin concentric, difference of adjacent layers of wire number is 6.Twisting method has the right interaction twist, twist, right to leftinteraction with twist, Zuo Tong Xiang Nian (see the wire ropetwisting method). The strands with fiber core and without the fiber core, with coating and without coating. By strand wire ropesystem with fiber core, also with a metal core (see cord). Made of single strands and multi strand of point contact lay wire ropeexample as shown in figure 2.
Point contact lay wire ropes are soft, manufacturing is simple,but the use of better performance of linear contact lay wire ropes, much less than the above contact wire rope. When in use, easy to produce the slip between steel wire in the cable,the function of the external force generated at the same time the steel wire on the two forms of bending stress, namely the wirethrough the pulley or drum generated when the primary bending stress and the inter layer steel wire mutual extrusion andproduce two times the bending stress. What is more, when the wire due to the loose structure floating, will have three times ofbending stress. Therefore, when in use, the steel wire ropebending stress, fatigue resistance difference. Point contact lay wire rope strand structure is loose, the stress of steel wire afterthe sliding between the large, large elongation, densitycoefficient is small. Although the ratio of linear contact lay wire ropes can bear more load, but life is low. With the development of technology, in addition to a small diameter (less than 10mm)and the large diameter (more than 60mm) and hoisting and packing need to consider convenient operation occasions, is no longer in use of this kind of steel wire rope.