Application And Study On Welding Procedure Of Central Groove

In recent years, with the rapid development of our country's coal industry, the competition among relevant colliery mechanical industry is also becoming more and more vigorous. The underground coal mining scraper conveyor of our company is developing towards severe type, super heavy, large-capacity, long distance, high reliability and automation. The central trough located in the middle is the key part of scraper conveyor; its reliability and wear resistance are directly related to the coal quantity and comprehensive property of the complete set of the equipment. So, improving the welding quality between ledge and middle plate, ledge and seal baseboard, will directly increase the welded joint quality of the scraper conveyor, and the life of the whole coal mining system.This paper researched on the chemical composition, carbon equivalent and cold crack sensitive index, and testifies the weldability of Super-high wear-resistant steel JEF-EH400, JEF-EH450, and ZG30MnSi. The results showed that the three kinds of steel had poor weldability; it is difficult to weld the Super-high wear-resistant steel to ZG30MnSi.On the basis of theoretical analysis, this paper researched the welding procedure qualification through the central trough plate, baseboard JEF-EH400,JEF-EH450 and ledge ZG30MnSi. The Welding method, welding material, preheating temperature, interlayer temperature, welding parameters had reached the optimal coordination, and then obtained the feasible welding process between super-high wear-resistant steel and ZG30MnSi.Application of X-ray detection test to welding joints, this paper researched the welding defects, as incomplete root penetration, cracks, porosity. The result showed that through welding parameters, improving operation technology and strengthening welding cleaning can solve such flaws, and then formulated the technical measures to prevent defects. In addition, according to welding deformation of the central trough, using advanced deformation, controlling welding heat input, choosing proper welding sequence, adopting positioning weld and slow cold process after weld can effectively control the deformation.