PRODUCTION OF 426×15-60 mm SEAMLESS HOT-ROLLED PIPES FOR STEAM BOILERS, STEAM PIPELINES AND MANIFOLDS OF PLANTS WITH HIGH AND SUPERHIGH STEAM PARAMETERS OF "10Х9МФБ-Ш"-GRADE STEEL Russian patent published in 2015 - IPC B21B19/04 

FIELD: process engineering.

SUBSTANCE: invention relates to pipe rolling. This process comprises casting of hollow ESR ingots, turning them and boring to 640×ID.440×3200±50 size hollow ingots-billets. The latter are heated to 1190-1200°C and rolled at PRU 8-16" with Pilger mills to rerolled 465×22×14100-14600 and 465×25×12200-12600 mm pipes with rolling-out µ=5.43 and µ=4.81, respectively, diameter reduction of 27.3% and with feed of sleeves to the source of strain m=15-17 mm. Seed ends and pilger heads are cut off rerolled pipes and straightened at six-roll straightener. Rerolled pipes are machined, cut to two equal lengths and rolled at "ХПТ" 450 mill to commercial pipes. Rerolled 465×22×7050-7300 mm pipes are rolled to commercial cold-rolled 426×15×10200-10500, 426×16×9500-9900 and 426×17×9000-9400 mm pipes with rolling-put µ=1.50, µ=1.41 and µ=1.34, respectively. Rerolled 465×25×6100-6300 mm pipes are rolled to commercial 426×18×8350-8600, 426×19×7900-8200 and 426×20×7600-7800 mm pipes.

EFFECT: higher surface quality and precision of geometrical sizes, lower metal input.

2 cl, 1 tbl