| 摘要 |
FIELD: metallurgy. ^ SUBSTANCE: for decreasing the relevant amount of blowhole in clax, created on the pipe surface, and exceeding of resistance to atmosphere corrosion, the pipe is made of steel containing the following mass in %: (0.15-0.22), Si (0.1-1.0), Mn (0.3-1.0), Cr (12.0-16.0) and it (pipe) has the relevant amount of blowhole in compliance with the thickness of clax from the sideview of the steel pipe, which satisfy the following correlation: <=-6.69 ln (ds) + 40.83, where: ds - thickness of the clax (mcm), ln - natural logarithm. The method of producing the pipe includes the pipe heating during 5-30 min up to the temperature (±3 + 20)° - 980° in atmosphere containing oxygen in total amount 2.5 volume.% or less and water vapor in amount of 15.0 volume % or less, the tempering of heated pipe with cooling speed 1-40°/sec from 980° up to the point with cooling speed less then 1°/sec, from point till point and with the cooling speed 5-40°/sec from point up to the temperature of environment, where point A lies in the interval 680-350° and point - 300-150°, dispersion of the water under high pressure 490 N/mm2 or higher to the side surface of the still pipe during that part of cooling from temperature of 900° up to the point of mentioned tempering. ^ EFFECT: reduction of the blowholes amount in the clax. ^ 16 cl, 6 tbl, 10 dwg, 1 ex |
