Tips for wire rope selection of lifting equipment
Which kind of wire rope is used in the hoisting machinery should be determined according to the type of work and the load, so that it can meet the requirements, but also be economical, reasonable, safe and reliable. Determining a reasonable safety factor is important for job safety, so it is better to choose a larger safety factor if possible. The diameter of the steel wire is different, the flexibility and elasticity are also different, and the steel rope used as the drag rope has small bending deformation, and the steel wire rope with a large diameter and a relatively large steel wire diameter of 6×19+l should be used. When the wire rope for lifting is wound around the pulley and the hoist drum, the bending deformation is large, and it is preferable to use a steel wire rope having a structure of 6×37+1. Such a wire rope is also suitable for use in cables for installation work. A softer 6×6l+1 wire rope should be used when used as a rope cover. In addition, the wire rope has the intersection of the winding and the winding. Among them, the advantage of the winding is that the rope is soft and easy to bend, and the contact surface with the pulley or the drum groove is large, and the wear is light. The disadvantage is that the ropes and the steel wires are twisted at a certain angle, so that the steel rope is easy to rotate and loosen, and the weight selection may cause danger and easy entanglement. For use on tow ropes and traction devices, it is not advisable to use re-crags and pulleys. The advantage of the winding is that the load distribution of each wire rope is uniform, so the strength is high, the tendency of twisting and entanglement is small, the work is safe, and the ropes are not easy to separate. The purpose is to lift the lifting device and sling. The wire rope is not only subjected to tensile force, but is also subjected to bending by being wound on the pulley or the drum a plurality of times. The smaller the diameter of the drum or pulley, the greater the stress generated by the rope. Therefore, in order to ensure the service life of the rope, the minimum ratio of the diameter D of the selected rope and the diameter D of the pulley and the drum is also specified. When the wire rope is selected, the breaking force can be determined according to the maximum static tensile force and safety factor under the working condition, and then the wire rope performance table can be consulted to select the required model and diameter.
