PRODUCTION OF LONG-SIZED 265×22×13000±300 AND 285×25×11750±50 mm-TUBE STOCK FROM HOLLOW ESR INGOTS-BILLETS OF "08Х10Н20Т2" AND "08Х10Н16Т2" GRATE STEEL FOR SUBMARINE PERISCOPE DRIVES Russian patent published in 2014 - IPC B21B21/00 

FIELD: process engineering.

SUBSTANCE: proposed process of making 265×22×13000±300 and 285×25×11750±50 mm pipe stock consists in using ESR hollow ingots-billets sized to 600xID.260×2050±50 and 600xID240.×2100±50 mm, respectively. Said ingots-billets are homogenised and heated in continuous furnace to ductility temperature. They are rolled at PRU 8-16'' with Pilger mill to rerolled pipe billets sized to 470xID.230×3550±50 and 480xID.240×3550±50 mm with rolling-out µ=1.71 and µ=1.66 and diameter reduction of Δ=21.7 and Δ=20.0%. The latter are heated without homogenisation to ductility temperature and rolled to commercial pipe billets sized to 285×42×13000±300 and 305×45×11750±250 mm with rolling-out of µ=4.03 and µ=3.62, diameter reduction of Δ=38.3 and Δ=35.4%, with machining allowance. Then, they are bored and turned to finished pipes.

EFFECT: lower metal input owing to ruled out cold drawing with additional austenitising.

6 cl