| 摘要 |
PURPOSE:To manufacture easily a stainless steel clad steel pipe which is excellent in its stress corrosion cracking resistance by making a coefficient of thermal expansion of an inner surface clad material larger than an outer surface base material, and adjusting a cooling condition of after a solution heat treatment, when manufacturing the stainless steel clad steel pipe. CONSTITUTION:When manufacturing a stainless steel clad steel pipe, a 23 Cr stainless steel, etc. whose coefficient of thermal expansion is larger than carbon steel of a base material are used as an inner surface clad material. It is brought to a solution treatment at a temperature of >=1,000 deg.C, and thereafter, a cooling speed of a stainless steel clad material of the inner surface is made larger than a cooling speed of carbon steel of an outer surface base material by execut ing a forced cooling from the inner surface. By this cooling, the stainless steel clad material of the inner surface becomes a compressed state, or a residual compression stress state being a tensile state of <=15kg/mm<2> against the carbon steel of the base material, and a stress corrosion cracking resistance of the stainless steel clad steel pipe is improved.
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