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AssigneesSumitomo Metal Industries, Ltd., Vallourec Mannesmann Oil & Gas France
InventorsShigeo Nagasaku, Kunio Goto, Shigeo Onishi, Hiroaki Ikegami
Estimating the term…
A threaded joint for steel pipes comprised of a pin 1 and a box 2 each having a threaded portion (1a, 2a) and an unthreaded metal contact portion (1b, 2b) exhibits adequate leakage resistance and galling resistance when used for makeup of oil country tubular goods with application of a green dope or even without any dope. The threaded joint has a first plating layer of Sn—Bi alloy plating or Sn—Bi—Cu alloy plating formed on the contact surface of at least one of the pin 1 and the box 2. The first plating layer may have a second plating layer selected from Sn plating, Cu plating, and Ni plating on its lower side and at least one layer of a lubricating coating, and particularly a solid lubricating coating, on its upper side.
A threaded joint for steel pipes comprised of a pin and a box each having contact surface including a threaded portion and an unthreaded metal contact portion, characterized by having a first plating layer selected from Sn—Bi alloy plating and Sn—Bi—Cu alloy plating formed on at least a part of the contact surface of at least one of the pin and the box.
A pin of a threaded joint for steel pipes having contact surface including a threaded portion and an unthreaded metal contact portion, characterized by having a first plating layer selected from Sn—Bi alloy plating and Sn—Bi—Cu alloy plating formed on at least a part of the contact surface.
A box of a threaded joint for steel pipes having contact surface including a threaded portion and an unthreaded metal contact portion, characterized by having a first plating layer selected from Sn—Bi alloy plating and Sn—Bi—Cu alloy plating formed on at least a part of the contact surface.
Dependencies are inferred from the claim text.