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:
Oct. 14, 2014
Filed:
Mar. 13, 2009
Kunio Goto, Kobe, JP;
Shigeo Nagasaku, Nishinomiya, JP;
Shigeo Onishi, Osaka, JP;
Hiroaki Ikegami, Nishinomiya, JP;
Kunio Goto, Kobe, JP;
Shigeo Nagasaku, Nishinomiya, JP;
Shigeo Onishi, Osaka, JP;
Hiroaki Ikegami, Nishinomiya, JP;
Nippon Steel & Sumitomo Metal Corporation, Tokyo, JP;
Vallourec Oil and Gas France, Aulnoye-Aymeries, FR;
Abstract
A threaded joint for steel pipes having excellent galling resistance, rust preventing properties, and airtightness without using a compound grease comprises a pin and a box each having a threaded portion and an unthreaded metal-to-metal contact portion serving as contact surfaces. The contact surfaces of at least one of the pin and the box are coated with a multi-layered structure comprising, from the bottom, a first layer formed from a first metal or alloy, a second layer formed from a second metal or alloy which is softer than the first metal or alloy, and an uppermost layer of a solid lubricating coating comprising a lubricating powder in an organic or inorganic binder.