METHOD OF MANUFACTURE OF COLD DRAWN TRADE PIPES OF 273×10×8700-9500 mm SIZE FROM TITANIUM ALLOYS PT-1M AND PT-7M Russian patent published in 2018 - IPC B21B19/04 B21B21/00 C22F1/16 

FIELD: metallurgy.

SUBSTANCE: method of manufacture of cold drawn trade pipes of 273×10×8700-9500 mm size from titanium alloys PT-1M and PT-7M includes ingot casting in vacuum-arc furnaces, forging ingots in forgings, turning forgings into blanks with size of 500±5×1750±25 mm, drilling in the blanks a central hole with a diameter of 90±5 mm, schooping Al₂O₃, heating in reheat furnaces in mufflers up to temperature of 1140-1160°C, piercing the blanks of 500±5×90±5×1750±25 mm size in a cross-rolling mill on a mandrel with 300 mm diameter with an elongation ratio μ from 1.39 to 1.46 in shells with a size of 515×in.315×2400-2590 mm, rolling shells in a pilgrim mill in the calibre of 351 mm with an elongation ratio of μ=4.78, with charging shells to the deformation zone m=18-20 mm, to tube stock with a size of 338×28×10300-11200 mm, cutting the tube stock into two pipes of equal length, boring and machining of hot drawn tube stock to tubular blanks with a size of 325×15×5150-5600 mm, rolling them in cold reducing rolling mills end route 325×15×5150-5600-273×10×8700-9500 mm with a relative reduction along the wall of δ_m=33.3% and an elongation ratio of μ_m=1.77.

EFFECT: mastering the production of a new type of pipes made of titanium alloys.

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