Title:
THREADED JOINT FOR PIPES AND METHOD FOR PRODUCING THREADED JOINT FOR PIPES
Document Type and Number:
WIPO Patent Application WO/2019/074103
Kind Code:
A1
Abstract:
Provided is a threaded joint for pipes, which has achieved excellent welding resistance without performing a surface roughening step, said excellent welding resistance being comparable to those in cases where a surface roughening step is performed, and which has low shouldering torque. A threaded joint (50) for pipes according to the present invention is provided with a pin (13) and a box (14). This threaded joint for pipes is provided with a Zn-Ni alloy plating layer (21) and a solid lubricating coating film (23). The Zn-Ni alloy plating layer (21) is formed on a contact surface of at least one of the pin (13) and the box (14), and contains 10-16% by mass of Ni. The solid lubricating coating film (23) is formed on the Zn-Ni alloy plating layer (21). The contact surface, on which the Zn-Ni alloy plating layer (21) is formed, has been ground. If Ra1 is the arithmetic mean roughness of the surface of the Zn-Ni alloy plating layer (21) and Ra2 is the arithmetic mean roughness of the contact surface, Ra1 is 0.1-3.2 μm, and Ra1 is larger than Ra2.
Inventors:
OSHIMA MASAHIRO (JP)
KIMOTO MASANARI (JP)
KIMOTO MASANARI (JP)
Application Number:
PCT/JP2018/038119
Publication Date:
April 18, 2019
Filing Date:
October 12, 2018
Export Citation:
Assignee:
NIPPON STEEL & SUMITOMO METAL CORP (JP)
VALLOUREC OIL & GAS FRANCE (FR)
VALLOUREC OIL & GAS FRANCE (FR)
International Classes:
F16L15/04; C23C28/00; F16L15/00; C25D5/26
Domestic Patent References:
| WO2017047722A1 | 2017-03-23 | |||
| WO2016170031A1 | 2016-10-27 | |||
| WO2017110686A1 | 2017-06-29 | |||
| WO2016170031A1 | 2016-10-27 |
Foreign References:
| JP2015506445A | 2015-03-02 | |||
| JP2008069883A | 2008-03-27 |
Other References:
See also references of EP 3696456A4
Attorney, Agent or Firm:
ASCEND IP LAW FIRM (JP)
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