The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 18, 2018
Filed:
Sep. 11, 2013
Nippon Steel & Sumitomo Metal Corporation, Tokyo, JP;
Vallourec Oil and Gas France, Aulnoye-Aymeries, FR;
Yousuke Oku, Tokyo, JP;
Tatsuya Yamamoto, Tokyo, JP;
Masaaki Sugino, Tokyo, JP;
Russell Elder, Houston, TX (US);
NIPPON STEEL & SUMITOMO METAL CORPORATION, Tokyo, JP;
VALLOUREC OIL AND GAS FRANCE, Aulnoye-Aymeries, FR;
Abstract
In a screw joint for a steel pipe, a taper angle of a tapered surface of a pin is substantially the same as a taper angle of a tapered surface of a box. In addition, the pin and the box interfere with each other in a radial direction while a seal surface of the pin and a seal surface of the box contact each other in a process of make-up between a male screw portion and a female screw portion, and at least apart of the seal surface of the pin comes into close contact with at least a part of the seal surface of the box over the entire circumference. Moreover, a contact pressure amplification mechanism, which increases a contact pressure between the seal surface of the pin and the seal surface of the box at the completion of the make-up, is further provided.