Title:
THREADED STEEL-PIPE FITTING
Document Type and Number:
WIPO Patent Application WO/2015/182128
Kind Code:
A1
Abstract:
This threaded fitting has, on the surface of a male thread (11), a solid coating (30) that exhibits fluidity when applied and is subjected to a hardening treatment after application. When fastening is complete, the crests (12) of the male thread (11) and the roots of a female thread, which face each other, are flat, and gaps are formed between those flat surfaces. A helical groove (40) that coincides with the helix angle of the threads is provided in advance in the crests (12) of the male thread (11). The maximum depth of said groove (40) is between 30 µm and 1/5th of the thread depth, inclusive. This threaded fitting prevents abnormal fastening torque and seizure during fastening without compromising strength performance.
Inventors:
SUGINO MASAAKI (JP)
GOTO KUNIO (JP)
GOTO KUNIO (JP)
Application Number:
PCT/JP2015/002662
Publication Date:
December 03, 2015
Filing Date:
May 26, 2015
Export Citation:
Assignee:
NIPPON STEEL & SUMITOMO METAL CORP (JP)
VALLOUREC OIL & GAS FRANCE (FR)
VALLOUREC OIL & GAS FRANCE (FR)
International Classes:
F16L15/04
Domestic Patent References:
| WO2011027433A1 | 2011-03-10 |
Foreign References:
| JP2013108556A | 2013-06-06 | |||
| JP2011106627A | 2011-06-02 | |||
| JP2007504420A | 2007-03-01 | |||
| JP2001507771A | 2001-06-12 | |||
| JP2010522855A | 2010-07-08 | |||
| JP2004507698A | 2004-03-11 |
Other References:
See also references of EP 3150895A4
Attorney, Agent or Firm:
ASCEND IP LAW FIRM (JP)
アセンド patent business corporation (JP)
アセンド patent business corporation (JP)
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