PRODUCTION OF SEAMLESS COLD-FORMED OIL-WELL TUBING SIZED TO 168,3×10,6×5000-10000 mm Russian patent published in 2015 - IPC B21B21/00 

FIELD: process engineering.

SUBSTANCE: invention relates to pipe rolling. Proposed process comprises casting of hollow ESR 470×110×2700 and 430×105×2700 mm ingots, boring and turning them to 460×100×2700 mm and 420×95×2700 mm ingots-billets. The latter are heated to ductility temperature and rolled at 234/239mm- and 199/204mm-tapered mandrels to rerolled 325×45×6400 and 260×30×8000 mm hot-rolled pipes. The latter are bored and turned to pipes-billets 310×30×3200 and 245×16×4000 mm in size. Pipe billets are rolled at cold-rolling mills to cold-formed 168.3×10.6×5000-1000 mm tubings in 310×30-273×23-219×16-168.3×10.6 mm sections with relative wall reduction δ_1m=23.3%, δ_2m=30% and δ_3m=33.8% and 245×16-219×13-168.3×10.6 mm with relative wall reduction of δ_1m=12.8% and δ_2m=18.5%.

EFFECT: lower metal input.

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