R & D of X90 SAWH Pipes

Generally described is the strip steel for the X90 linepipe;studied are the main aspects of the X90 SAWH pipe,including the mechanical properties,and the structural morphology,hardness and hardness distribution of the welded joint.As a result,relevant suggestions are proposed,namely,optimizing the alloy elements of the strip steel,enhancing the strip's end yield strength and cooling velocity,reducing the strip coiling temperature,further investigating the effect by the specimen type on the result of the tensile test,and establishing the standard of the X90 linepipe.