发明名称 |
SURFACE ADJUSTMENT TREATMENT PRIOR TO CHEMICAL TREATMENT OF STEEL PRODUCT |
摘要 |
<p>By subjecting a threaded joint for OCTG (oil country tubular goods) to surface conditioning with an aqueous solution of potassium tetraborate or sodium tetraborate prior to manganese phosphate chemical conversion treatment, a manganese phosphate chemical conversion coating having coarse crystal grains with an average crystal grain diameter of 10 - 110 micrometers is formed on the surface of the steel member which may be any steel including a high Cr steel. This manganese phosphate chemical conversion coating can hold a large amount of a liquid lubricant, and it is effective at preventing the occurrence of galling at the time of makeup of a threaded joint for OCTG.</p> |
申请公布号 |
EP1705265(A4) |
申请公布日期 |
2009.05.13 |
申请号 |
EP20040819957 |
申请日期 |
2004.12.06 |
申请人 |
SUMITOMO METAL INDUSTRIES, LTD. |
发明人 |
IZAWA, MASARU;GOTO, KUNIO;UJITA, Y.;TAKANO, T. |
分类号 |
C23C22/78;C23C22/18;F16L15/00;F16L58/18 |
主分类号 |
C23C22/78 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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