| 摘要 |
FIELD: metallurgy.SUBSTANCE: method includes manufacturing of jackets from bars of electroslag steel of grade 10GN2MFA, manufacturing of cylindrical bushings from bars of electroslag steel of grade 08H18N10t and manufacturing of end rings from solid-cast stocks of carbon steel grades. In electroslag bars they drill through holes, then they heat them to plasticity temperature, stitched in a cross-rolling mill on mandrels into cartridges, which are rolled in a pilgrim mill into tube stocks. Tube stocks with size 535×vn.245×2600-2650 and 585×vn.240×1800-1850 mm from steel 10GN2MFA are bored and turned into cylindrical jackets-stocks with size 520±1.0×vn.265+1.0/-0×1300 and 570±1.0×vn.255+1.0/-0×1750 mm. Tube stocks with size 280×77×4000 and 270×82.5×3700 mm from steel 08H18N10T are bored and turned into cylindrical bushings with size 265+0/-1.0×52.5×1300 and 255+0/-1.0×57.5×1750 mm. Solid-cast stocks of carbon steels with diameter 550 and 600 mm are bored, a through hole is drilled in stocks, and they are welded with a solid seam to one of sides of cylindrical jackets to form sleeves. Cylindrical bushings are inserted into formed sleeves and are connected by welding assembly seams with jackets and end rings. Produced bimetal stocks are heated to temperature 1250-1260°C, stitched into the cross-rolling mill into bimetal cartridges with size 540×vn.315×1910 and 600×vn.365×2700 mm, which are rolled on a pilgrim mill into hot-rolled tube stocks with size 371×50.5×4500 and 446×54×5100 mm. Hot-rolled tube stocks are bored and turned into finished bimetal pipes.EFFECT: reduced number of pipe defects in thickness of a plating layer.6 cl, 1 dwg, 2 tbl |
