BILLET FOR PIERCING AND ROLLING AT HELICAL ROLLING TWO-ROLL MILL OF 650×500BH×3250-3650 mm SLEEVE-BILLET FOR THEIR REROLLING TO COMMERCIAL 610×36,53×3150-3550 mm PIPES OF 15X5M-GRADE STEEL COMMUNICATIONS OF OIL REFINERIES WITH HIGHER-PRECISION GEOMETRICAL SIZES

摘要

FIELD: metallurgy.SUBSTANCE: this billet features cylindrical shape with ends shaped to spherical convex surfaces and axial 100±5.0 mm diameter bore. Billet bottom end features spherical convex surface on length L=0.12L±15, with end diameter D=0.92D±5.0. Biller outer surface is conjugated with diameter of the end with radius R=0.93R±5.0. Billet shrinkage end features spherical convex surface on length L=0.08L±10 with end diameter D=0.97D±5.0. Biller outer surface is conjugated with diameter of the end with radius R=0.96R±5.0, where L=1630±50 is billet length, mm; D=630±10 is billet diameter, mm; Ris billet radius, mm.EFFECT: lower metal input, higher precision of sizes, increased length of pipes.1 dwg, 1 tbl