METHOD OF MANUFACTURING SEAMLESS COLD PIPES OF SIZE 168, 3Kh10, 6Kh10, 6Kh5000-10000 mm OF CORROSION-RESISTANT ALLOY OF KhN30MDB GRADE Russian patent published in 2017 - IPC B21B23/00 B21B19/04 B21B21/00 

FIELD: metallurgy.

SUBSTANCE: casting is carried out of centrifugally cast billets of 500×125×2600±50 mm, boring of centrifugally-cast billets is made into the mechanically processed billets of size 500×115×2600±50 mm, billets are heated to the plasticity temperature, rolled on Pilger mill into stock hot-rolled pipes 325×45×7600-8000 mm. Stock hot-rolled pipes are cut into pipes of equal length, stock hot-rolled pipes are bored and turned into pipe billets of size 310×30×3800-4000 mm. Mechanically processed pipe billets of size 310×30×3800-4000 mm are rolled at KhPT mills on the routes: 310×30×3800-4000 - 273×23×5300-5500 - 219×16×9100-9500 mm, cold-rolled pipes of size 219×16×9100-9500 mm are cut into two pipes of size19×16×4550-4750 mm and then they are rooled on the KhPT mills into trade pipes of size 168.3×10.6×5000-10000 mm.

EFFECT: reduced metal consumption and pipes cost.

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