Large-aperture spiral welded steel pipe with metal linings and manufacturing method thereof

Abstract The present invention discloses a large-aperture spiral welded steel pipe with metal linings and a manufacturing method thereof. The steel pipe includes a pipe body spirally winded by a main steel belt; a first lining and a second lining are arranged on 5 an inner wall of the pipe body, the first lining is spirally laminated on the surface of the main steel belt, the width of the first lining is smaller than the width of the main steel belt, the second lining is spirally laminated on a spiral seam formed between adjacent pipe bodies, left and right sides of the second lining are respectively welded with the adjacent first lining, and the first lining and the second lining cover the inner 10 wall of the entire pipe body; and a reinforcement ring with a semi-closed section is spirally arranged along an outer wall of the pipe body, and a spiral passage is formed between the inner wall of the reinforcement ring and the outer wall of the pipe body. The present invention has the advantages that the metal linings arranged on the inner wall of the steel pipe can improve the corrosion resistance and the abrasion resistance 15 of the steel pipe and avoid fluid pollution; the reinforcement ring arranged on the outer wall of the steel pipe can improve the second moment of area in a circumferential direction of the pipe wall, and the wall thickness of the main steel belt is smaller than the wall thickness of a common steel pipe, so that the cost is reduced. 20 Fig. 10