PRODUCTION OF 377×14-60 mm SEAMLESS HOT-ROLLED PIPES FOR STEAM BOILERS, STEAM PIPELINES AND MANIFOLDS OF PLANTS WITH HIGH AND SUPERHIGH STEAM PARAMETERS FROM ESR INGOTS OF '10Х9МФБ-Ш'-GRADE STEEL

摘要

FIELD: process engineering.;SUBSTANCE: invention relates to metallurgy. Proposed method comprises ESR smelting of ingots, their turning to ingots-billets sized to 490×1750±50 mm and 565×1750±50 mm and boring 100±5 mm diameter holes therein. Said billets are heated to ductility temperature and pierced at helical rolling mill to het the sleeve billets. Said billets are cooled, repaired is required and reheated from cold state to ductility temperature. Sleeve billets are pierced-rolled at helical rolling mill and rolled at Pilger mills and rolled to commercial pipes. Then, they are subjected to ultrasound control and acceptance with diameter and wall depth allowances of +1.25/-1.0% and +20/-5.0%, respectively. Pipes sized to 377×14-19 mm are produced at CPR 450 mill from hot rerolled pipes sized to 426×21 mm and 426×23 mm. Commercial 377x20-30 mm pipes are produced at PRU 8-16'' with Pilger mills from hollow ESR ingots-billets sized to 540× ID360×3200±50 mm and 540×ID340×3200±50 mm. Commercial 377×31-40 mm pipes are produced from hollow ESR ingots-billets sized to 540× ID0.200×2100±50 mm. Commercial 377×41-60 mm pipes are made from EST ingots sized to 565×100×1750 mm.;EFFECT: mechanical properties and geometry complying with standing specifications, lower metal input and higher PRU efficiency.;7 cl, 1 tbl