Abstract: Studied here in the article is the manufacturing process of the Φ50.8 mm×0.89 mm S32750 super duplex stainless steel ultra-light-wall pipe. The said welded pipe is successfully produced by means of the DC tungsten argon arc welding process together with the innovative dual radius W reverse bending and cold bending forming process,and the weld seam leveling process. The research result shows that the welded pipe possesses mechanical properties,the process properties,and the corrosion resistance in compliance with relevant requirements as specified under applicable specification,good,smoothly transitional and round weld form without any of the defects like undercut;the microscopic structure analysis reveals that the weld seam zone is composed of ferrite and austenite that are uniformly distributed;and the hardness test shows that the hardness of the weld seam,the HAZ and the base metal is ≤300 HBW,and the hardness error is controlled within 15 HBW.