PRODUCTION OF "вн.279×36 (351×36)" AND "вн. 346×40" (426×40) mm PIPES FOR NUCLEAR POWER STATIONS FROM "10ГН2МФА" AND "08Х18Н10Т" GRADE STEELS WITH 7 mm INNER CLAD PLY Russian patent published in 2015 - IPC B21B21/00 

FIELD: process engineering.

SUBSTANCE: invention relates to pipe rolling. This process comprises making of shells from ESR ingots of "10ГН2МФА" grade steel, making of sleeves from ESR ingots of "08Х18Н10Т" grade steel and making of rings from continuously cast billets of carbon steels. Though holes are bored in ESR ingots to be heated to ductility temperature and pierced at helical rolling mills to sleeve to be rolled at Pilger mill to rerolled pipes. The latter are bored and turned to pipes-billets 570× ID260×1750 and 570× ID265×4000 mm in size. Sleeves 260×80×1750 and 256×78×1750 in size are made from ESR ingots by turning them and piercing the through hole therein. End 600 mm diameter rings are produced by turning of billets, bring through hole therein and cutting to measured length. Sleeves are fitted in shells. End rings are welded to one end of said shells while other shell end is welded with field joint. Produced billets are pierced to bimetal sleeved to be rolled to rerolled 426×40×8000 and 470×45×6300 mm pipes and, then, to cold-rolled commercial pipes.

EFFECT: lower metal input, decreased clad ply flaws.

3 tbl