Vallourec & Mannesmann Oil & Gas France

Nippon Steel Sumitomo Metal Corporation

Sumitomo Metal Industries, Inc.

Nippon Steel Corporation

Chugoku Marine Paints, Ltd.

Vallourec Mannesmann Oil & Gas Grance

Vallourec Oil and Gas France

Ryuichi Imai

Yasuhiro Yamamoto

Kunio Goto

Masaru Takahashi

Keishi Matsumoto

Takayuki Kamimura

Yasuhiro Ogawa

Michihiko Iwamoto

Masanari Kimoto

Shigeo Nagasaku

Kunihiro Fukui

Hiroaki Ikegami

Shigeo Onishi

Stéphanie Raï

Tomomitsu Nagareo

Yoshinori Kameda

Shigeki Fukumoto

Junichi Minami

Kaoru Takanashi

In a threaded joint for pipes constituted by a pin and a box, each having a contact surface comprising a threaded portion and an unthreaded metal contact portion, the contact surface of the pin has a solid corrosion protective, preferably transparent coating based on a UV-curable resin and the contact surface of the box has a solid lubricating coating having plastic or viscoplastic rheological behavior which is preferably formed by the hot melt technique from a composition comprising a thermoplastic polymer, a wax, a metal soap, a corrosion inhibitor, a water-insoluble liquid resin, and a solid lubricant.

Threaded joint for pipes

A threaded joint for steel pipes for use in an oil well which has improved galling resistance and which is protected from rusting comprises a pin and a box each having a contact surface including a threaded portion and an unthreaded metal contact portion. The contact surface of at least one of the pin and the box has a lower layer of a viscous liquid or semisolid lubricating coating comprising at least wax and a fatty acid alkaline earth metal salt and not containing a harmful heavy metal such as lead and an upper layer of a dry solid coating formed from an aqueous resin coating composition, an organic solvent type coating composition, or an ultraviolet curing coating composition.

Oil well pipe with threaded joint

A thin and highly transparent coating having excellent air tightness, adhesion to a substrate, lubricating properties, galling resistance, and corrosion resistance is formed on the surface of a metal substrate and particularly on the surface of a threaded joint which is used for connection of oil country tubular goods. A photocurable composition comprising (A) a photocurable (meth)acrylate resin, (B) a (meth)acrylate monomer selected from a monofunctional (meth)acrylate monomer and a difunctional (meth)acrylate monomer, (C) a trifunctional or higher multifunctional (meth)acrylate monomer, (D) a photopolymerization initiator, (E) a benzotriazole anticorrosive agent, (F) an anticorrosive pigment selected from a phosphate anticorrosive pigment and calcium ion-exchanged silica, and (G) a phosphate ester is used to form a photocured coating.

Photocurable composition suitable for rust prevention of a threaded joint for steel pipes

A lubricating coating which is free from harmful heavy metals is formed on a premium threaded joint for pipes constituted by a pin and a box each having a contact surface comprising a threaded portion and an unthreaded metal contact portion (a sealing surface and shoulder) in order to provide the joint with galling resistance, gas-tightness, and anticorrosive properties such that the unthreaded metal contact portion is prevented from yielding even when the joint is made up with a high torque. The lubricating coating comprises one or both of a rosin and calcium fluoride; metal soap; wax; and a basic metal salt of an aromatic organic acid, and preferably it further includes a lubricating powder, magnesium carbonate, and/or a carbohydrate, particularly a cyclodextrin.

Threaded joint for pipes having a lubricating coating

A threaded joint for steel pipes for use in an oil well which has galling resistance and which is protected from rusting comprises a pin and a box each having a contact surface including a threaded portion and an unthreaded metal contact portion. The contact surface of at least one of the pin and the box has a lower layer of a viscous liquid or semisolid lubricating coating comprising at least wax and a fatty acid alkaline earth metal salt and not containing a harmful heavy metal such as lead and an upper layer of a dry solid coating formed from an aqueous resin coating composition, an organic solvent type coating composition, or an ultraviolet curing coating composition.

Threaded joint for steel pipes

A threaded joint for steel tubes has a contact surface () including a threaded portion and a non-threaded metal-to-metal contact portion. The contact surface of at least one of a pin and a box of the joint is coated with a first plating layer () made of a Cu&#x2014;Zn alloy or a Cu&#x2014;Zn-M1 alloy (wherein M1 is at least one element selected from Sn, Bi, and In). An undercoat () of one or both of a Ni plating layer () and a Cu plating layer () and an overcoat of a Sn-M2 alloy plating layer () (wherein M2 is one or more elements selected from Bi, In, Ni, Zn, and Cu) may be formed below and above the first layer, respectively. A solid lubricating coating () and a viscous liquid or semisolid lubricating coating () may also be formed atop the plating layer as a lubricating coating ().

Threaded joint for steel tubes

A threaded joint for steel pipes for use in an oil well which has enhanced galling resistance and which is protected from rusting comprises a pin and a box each having a contact surface including a threaded portion and an unthreaded metal contact portion. The contact surface of at least one of the pin and the box has a lower layer of a viscous liquid or semisolid lubricating coating comprising at least wax and a fatty acid alkaline earth metal salt and not containing a harmful heavy metal such as lead and an upper layer of a dry solid coating formed from an aqueous resin coating composition, an organic solvent type coating composition, or an ultraviolet curing coating composition.

A threaded joint for a steel pipe comprises a pin and a box with a contact surface having a threaded part and a unthreaded metal contact part, wherein a solid lubricating film containing one or more kinds of lubricating powders selected from graphite, mica, calcium carbonate and kaolin, a copper powder, and a binder is formed on at least one contact surface of the pin and the box. An object of the present invention is to provide a threaded joint for a steel pipe which allows for repeated fastening and loosening of a threaded joint without adversely influencing on a human body and environment, and is excellent in galling resistance, rust preventing property and gas tightness.

Threaded joint for steel pipe

A threaded joint for steel pipes comprises a pin () and a box () each having a threaded portion (or) and an unthreaded metal-to-metal contact portion (or) as contact surfaces which contact each other when the joint is fastened. The contact surfaces (andand/orand) of at least one of the pin () and the box () are coated with a lower layer of a solid lubricating coating containing a solid lubricating powder (e.g., molybdenum disulfide, tungsten disulfide, or graphite) and a binder (e.g., an epoxy or other organic resin) and an upper layer of a solid corrosion protective coating formed by an organic resin which does not contain solid particles.

In a protector for protecting a trapezoidal female thread of a pipe formed to an end thereof, the protector has a male thread formed thereto so as to be threaded with the female thread as well as the height of the thread of the male thread is made larger than the height of the thread of the female thread. With this arrangement, a surface treatment applied to the surface of the female thread or a male thread formed to the end of the pipe can be prevented from being damaged, and in particular, a surface treatment applied to a guide flank surface, a load flank surface, a corner portion, and the like of the thread can be prevented from being subjected to wear, damage, and the like.

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Kainan, Japan

Ryuichi Imai