Fatigue is one of the main reasons for the occurrence o […]
Fatigue is one of the main reasons for the occurrence of more broken wires inside the elevator wire rope. The broken wire of the elevator wire rope around the moving part of the traction sheave is the result of the joint action of bending fatigue and wear fatigue, and the research on the production process and the nature of fatigue It helps to take measures in the production process to improve the fatigue resistance of elevator wire ropes, extend the service life of elevator wire ropes, reduce operating costs, and improve the safety and reliability of elevator operation.
The metallographic structure of high-quality carbon steel wire suitable for drawing and obtaining the best mechanical properties is a sorbite structure. In the production process, the surface of the steel wire is damaged, or severe scratches, plaques, rust pits, and non-metallic inclusions formed during the steel smelting process are easy to form fatigue sources.
The content of non-metallic inclusions in the steel and the size of the particle size have a crucial influence on the fatigue properties of the steel wire rope, because the reticular ferrite in the metallographic structure after the Sorbite transformation promotes the rapid expansion of the fatigue crack, so the lead hardened steel wire Reticulated ferrite is not allowed. The austenitizing temperature of steel wire and the isothermal transformation temperature of lead quenching have a decisive influence on the production of reticular ferrite. The automatic control of furnace temperature and lead temperature technology in lead quenching production line is beneficial. The uniformity of the Sorbite structure, the lead liquid circulation is beneficial to obtain a uniform sootite structure in the steel wire at different positions of the lead pan, so as to ensure the uniformity of the steel wire after quenching, thereby ensuring the mechanical property fluctuation after the steel wire is drawn. The smallest range.