Abstract: Described in the article are the research and development activities for the Φ1 524 mm×20.3 mm X90 SAWH pipe, including optimizing the pipe manufacturing processes, particularly developing the pipe formation and welding processes, ensuring welding joint to have excellent performance by means of properly controlling such technological design indexes as forming stress, welding bevel blunt edge, welding speed, and low linear energy output, etc., and solving the problem of inconsistent low-temperature impact toughness in the weld seam and the HAZ as always encountered with in manufacturing hi-grade heavy-wall welded pipes.It is concluded via relevant testing and evaluation as performed by the third party that the Φ1 524 mm×20.3 mm X90 SAWH pipe as developed has its all quality indexes up to specified product technical requirements, having been quite ready for massive production.