FIELD: metallurgy.
SUBSTANCE: invention relates to metallurgy, and namely to production of large tongue-and-groove Larsen sections. Claimed process comprises the billet heating, section rolling and cooling. Said billet is produced by longitudinal slitting of dismantled large-diameter main line pipe to two-four parts with transverse bulge. The billet with said bulge upward is heated in pusher-type roller heating furnace to 950÷1050°C at the rate of 60÷120°C/min. At said position it is fed to the rolling mill to roll it to tongue-and-groove section in four rolling passes at the specified rolling speed and common rolling-out. Then, tongue-and-groove section rolled at 760÷820°C is cooled at the rate of 150÷250°C/sec to 350÷460°C at the roller-type quenching machine. Note here that the section horizontal and inclined flange relative positions are fixed to prevent the section lengthwise flexure. Then, sections are stacked four pieces in a stack, their ends being cut to required length by band-saw and cooled in air.
EFFECT: higher precision of sizes, decreased specific weight.
2 dwg
