LSAW pipe (Longitudinal Submerged Arc Welded pipe) is a straight-seam welded steel pipe made by forming steel plate into a cylinder and welding the longitudinal seam with submerged arc welding. It’s commonly specified for large-diameter, heavy-wall line pipe and structural piles where buyers need stable dimensions, inspectable weld quality, and project-ready coatings such as 3LPE or FBE.
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