Production method of ultra-large-diameter duplex stainless steel diameter-forged pipe blank

• Main Authors: LI JUN, WEI HAIRUI, PEI MINGDE, LIANG XIANGXIANG, HAO WENHUI, HOU WENJUN, LI GUOPING, QIN YUHANG
• Format: Patent
• Language: Chinese; English
• Published: 16.07.2024
• Subjects: FORGE FURNACES; FORGING; HAMMERING; MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVINGMATERIAL; PERFORMING OPERATIONS; PRESSING METAL; PUNCHING METAL; RIVETING; TRANSPORTING

The invention discloses a production method of an ultra-large-diameter duplex stainless steel diameter-forged tube blank, which comprises the following steps: selecting a 8.4 t square billet as a blank, heating the square billet at 1250 +/-10 DEG C for 2.0-8.0 hours, and upsetting the square billet to a round billet with the diameter phi of 900-1000mm after the square billet is discharged from a furnace; the round billet is subjected to diameter forging to form a pipe billet with the diameter phi being 500-600 mm, in the diameter forging process, the heating temperature is 1250 +/-10 DEG C, the heating time is 2.0-4.0 h, the initial forging temperature is 1050-1150 DEG C, three-section forging is adopted in the diameter forging, and the forging deformation rates of the first section of diameter forging, the second section of diameter forging and the third section of diameter forging are 5-8%, 10-15% and 20-30% respectively; and the pipe blank is directly put into a furnace for annealing, the annealing tempera