发明名称 |
THREADED JOINT FOR STEEL PIPES |
摘要 |
A threaded joint for steel pipes constituted by a pin having male threads and a box having female threads is improved with respect to ease of insertion of the pin and galling resistance of the threaded portions. The stabbing flanks of the threads in a complete thread portion of one of the pin and box has a two-step stabbing shape having a chamfer. The two-step stabbing shape has a stabbing flank angle α of 5-45° and a chamfer angle &bgr; of 20-60°. The ratio h/H of the chamfer height h to the thread height H of the pin is 0.25-0.50, or the ratio of the cross-sectional area of the chamfered portion to the overall cross-sectional area of the stabbing flank is made at least a value corresponding to a chamfer height ratio h/H of 0.25 and at most a value corresponding to a chamfer height ratio of 0.50. |
申请公布号 |
EA015427(B1) |
申请公布日期 |
2011.08.30 |
申请号 |
EA20090070910 |
申请日期 |
2008.04.02 |
申请人 |
SUMITOMO METAL INDUSTRIES, LTD.;VALLOUREC MANNESMANN OIL & GAS FRANCE |
发明人 |
NAKAMURA KEIICHI;HAMAMOTO TAKAHIRO;SUGINO MASAAKI;YAMAGUCHI SUGURU |
分类号 |
F16L15/04 |
主分类号 |
F16L15/04 |
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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