Abstract: The welding technology of high grade nonoriented silicon steel in acid continuous rolling units was researched in this paper , and the key and main factors of affecting the weld joint quality of high grade nonoriented silicon steel, such as the welding speed, the weld gap, the annealing current, the defocus amount, were defined. Meanwhile, by analyzing the actual microstructures of weld joints of different silicon steels varied with different silicon content under different annealing current, it was found that the self properties of different silicon steels make great effect on the passing compacity of weld joints. So then the improvment suggestions were put forward, which were proved that passing compacity of weld joints has been really improved in actual production.

Key words: acid continuous rolling mill, high grade nonoriented silicon steel, laser welding