| 摘要 |
FIELD: metallurgy.SUBSTANCE: ingots are casted with the size 680×out495×2600±100 mm which are bored out and grinded in work piece ingots with the size 660×out510×2600±100 mm, heated up to the temperature 1260-1270°C, blown with compressed air, into work piece ingots the greasing graphite mix is injected with table salt in the ratio 50/50, weight 1000-1500 g and rolled into process pipes with the size 542×30×5800-6350 mm on a pilger mill with the calibre 550 mm into rolls with the diameter of barrel 1150 mm, on conical mandrels with the diameter 489/491 mm with the coefficient of polishing "?" = 7.0-7.5, elongation ratio µ= 2.8 and diameter crimping ? = 17.88% then the boring and grinding of the process pipes into commodity seamless hot-rolled pipes with the tolerance by diameter ±0.8% and by wall ±10.0% are performed.EFFECT: improvement of accuracy of geometrical sizes of pipes, quality of their surface and mechanical properties.3 cl, 1 tbl |
