How to choose wire rope

Wire ropes are standard products in various industrial countries, and are mainly used in hoisting, pulling and other transportation requiring high-strength wire ropes. The diameter, number of strands, number of wires per strand, tensile strength and sufficient safety factor can be selected according to the needs of use.

The steel wire is generally made of high-quality carbon steel No. 65, which can achieve high strength after repeated cold drawing and heat treatment. Ordinary occasions can be twisted with smooth steel wire, that is, after cold drawing of the rope making steel wire, the steel wire rope can be directly twisted without any surface treatment. In wet or open-air environments, the steel wire rope twisted by galvanized steel wire can be used to enhance rust prevention. performance.

Galvanized steel wire rope includes two methods: hot-dip galvanizing and electro-galvanizing. The thicker the galvanized layer, the better the anti-corrosion effect. Or the material of stainless steel is better, but the price will be very high compared to galvanized. In addition to the wear of the outer layer steel wire, the steel wire rope is mainly broken due to metal fatigue caused by repeated bending when it goes around the pulley and the drum. Therefore, the ratio of the diameter of the pulley or the drum to the wire rope is an important factor in determining the life of the steel wire rope. If the ratio is large, the bending stress of the steel wire is small and the service life is long. The appropriate ratio must be determined according to the application. If the wear, corrosion degree of the surface layer of the wire rope or the number of broken wires in each twisting pitch exceeds the specified value, it should be scrapped.

The specifications of steel wire ropes are classified according to the surface treatment process: oiled steel wire ropes, hot-dip galvanized steel wire ropes, electro-galvanized steel wire ropes, and plastic-coated steel wire ropes. Among them, oiled wire ropes are the most widely used, and are mostly suitable for lifting and hoisting applications. Oiling the surface of wire ropes can prevent rust and lubricate, and the price is relatively cheap. Hot-dip galvanized steel wire rope is a layer of zinc plated on the surface of the steel wire rope through heat treatment. Usually, the hot-dip galvanized zinc layer is thicker and can be guaranteed not to rust for 20 years in the air. Compared with hot-dip galvanized steel wire rope, the anti-rust function of electro-galvanized steel wire rope is slightly worse. Generally, it can only stay in the air for 3-5 years without rusting, but electro-galvanized steel wire rope will be relatively brighter than hot-dip galvanized surface. The plastic-coated steel wire rope is to coat a layer of pvc on the surface of the steel wire rope, which has the effect of lifting buffer and wear resistance.

Wire rope specifications are classified by structure: 6*37+FC, 6*37+IWS, 6*37+IWR, 6*19+FC, 6*19+IWS, 6*19+IWR, 6*19S, 6*19W , 6*29Fi, 6*25Fi, 6*26SW, 6*31S, 6*36SW, 6*37S, 18*7, 18*19, 17*7, 8*19, 35W*7, etc. The number in front represents how many strands the wire rope is made of, and the number in the back represents how many wires each strand of the rope contains. For example, 6*37 means that the wire rope specification has a total of 6 strands, and each strand has 37 wires. 6*7 6*19 6*37 are generally point contact wire ropes, 6*9w 6*19s 6*19w 6x36sw are generally line contact wire ropes, 6k*19w 6k*36 are generally surface contact wire ropes, 18*7 18*19 35 *7 18*19s 35w*7 is generally multi-layer non-rotating line contact, 18*7k 35w*7k is generally multi-layer non-rotating surface contact.

Steel wire rope standard: GB/T 20118-2017 General technical conditions for steel wire rope.