MANUFACTURING METHOD OF COLD-ROLLED MERCHANTABLE TUBES WITH SIZE OF 170×370 mm FROM STEEL GRADE '16Х12МВСФБР-Ш (ЭП823-Ш)' FOR FAST NEUTRON REACTORS OF NEW GENERATION

摘要

FIELD: metallurgy.;SUBSTANCE: ingots cast by electroslag remelting with the size of 485×1600±25 mm are turned into cakes with the size of 470×1600±25 mm. A central hole with diameter of 100±5 mm is drilled in them, heated in a continuous furnace to the temperature of up to 1120-1140°C and pierced in a mill for transverse screw rolling into shells with the size of 480×in315×2500±40 mm. Shells are rolled on pilger mills on mandrels with the diameter of 282/286 in a 340 mm groove into process hot-deformed tubes with the size of 338×25×9000±200 mm with drawing µ_n=4.07-4.08, swaging as to diameter Δ=(29.5-29.6)% and supply of shells to deformation zone m=16-18 mm. Straightening of tubes in a six-roll straightening machine is performed till curvature of h≤3 mm throughout the length of 4500±100 mm. Process tubes are cut, bored and turned into process tubes with the size of 325×12×4500±100 mm with metal removal along inner and outer surfaces Δ_RI=Δ_RO≤6.5 mm with surface cleanliness R_z≤30 mcm, with an allowance as to diameter of ±0.8% and wall thickness of ±10%. Process tubes are rolled over into merchantable tubes with the size of 170×3.0×15200±320 mm and cut into semi-finished tubes with the size of 170×3.0×370 mm.;EFFECT: reduction of a metal consumption coefficient.