Development of Manufacturing Process for P91 Steel Large Diameter Thick Wall Boiler Pipe

A P91 steel large diameter thick wall seamless steel pipe is developed by selecting reasonable chemical composition, billet heating process, hot rolling process and heat treatment process.The testing results show that all of the geometrical dimensions, the room& high temperature mechanical properties of the product can meet the requirements of ASME SA 335/SA 335M-2010 and GB 5310-2008.Its endurance strength under 600℃and 10⁵h is 96.32 MPa, which meets the requirements for boiler construction of supercritical units of thermal power plants and for high temperature pipelines of power stations.