Vallourec Oil and Gas France

Nippon Steel Sumitomo Metal Corporation

Sumitomo Metal Industries, Inc.

Nippon Steel Corporation

Vallourec & Mannesmann Oil & Gas France

Suguru Yamaguchi

Masaaki Sugino

Keiichi Nakamura

Michihiko Iwamoto

Bertrand Maillon

Shin Ugai

Claire Patureau

Takahiro Hamamoto

Daly Daly

Sylvain Beigneux

Takashi Okada

Masayoshi Sasaki

Eric Verger

Shigeo Nagasaku

Keita Inose

Masahiro Oshima

Takahiro Takano

Fumio Ota

Gabriel Briquet

A threaded joint is constructed of a pin and a box. The pin includes, in order from an end thereof, a shoulder surface, a nose portion, a first sealing surface, a first male threaded portion, an annular portion, a second sealing surface, and a second male threaded portion. The box includes a shoulder surface, a recessed portion, a first sealing surface, a first female threaded portion, an annular portion, a second sealing surface, and a second female threaded portion. In the threaded joint, in a fastened state, the shoulder surfaces are in contact with each other, the first sealing surfaces are in contact with each other, the second sealing surfaces are in contact with each other, a clearance is provided between the nose portion and the recessed portion, a clearance is provided between the annular portions.

Threaded joint for steel pipes

In a threaded joint for steel pipes comprising a pin () and a box (), each having a threaded portion (or), a sealing surface (or), and a shoulder surface (or), the sealing surface () of the pin () is formed by a tapered surface, and the sealing surface () of the box () is formed by a first curved surface portion with a large radius of curvature in the range of 15-120 mm, a tapered surface portion, and a second curved surface portion with a large radius of curvature again in the range of 15-120 mm.

A threaded tubular connection includes a female threaded portion at a first tubular component end and a male threaded portion at a second tubular component end, the female threaded portion including a female thread, at least one female sealing surface on its inner peripheral surface, and at least one female axial abutment surface, the male threaded portion including a male thread, at least one male sealing surface on its outer peripheral surface, at least one axial abutment surface, and a lip disposed between the sealing surface and an axial abutment surface located at a free end of the threaded portion distant from the thread, the male thread being made up into the female thread such that at least one male axial abutment surface is in contact with at least one female axial abutment surface, at least one male sealing surface being in interference contact with at least one corresponding female sealing surface, the portion of the lip between the sealing surface and the axial abutment surface being radially distant from a corresponding surface of the other threaded portion, at least one leak channel being provided in one of the threaded portions to place the chamber formed between the lip and the corresponding surface of the other threaded portion in communication with the interior of the connection.

Threaded connection comprising at least one threaded element with an end lip for a metal tube

A threaded joint for steel pipes comprising a pin () and a box (). The pin has a male thread () and a lip () which comprises (i) a sealing surface () and (ii) a nose portion () provided with a shoulder surface. The box has a female thread (), a sealing surface () and a shoulder surface. The shoulder surface of the pin comprises two distinct adjacent surfaces, main shoulder () in the inner side and sub shoulder () in the outer side. Correspondingly, the shoulder surface of the box comprises two distinct adjacent surfaces, main shoulder () in the inner side and sub shoulder () in the outer side. The main shoulder surfaces of the pin and box are disposed such as to prevent a radially inward deformation of the lip end, and the sub shoulder surfaces of pin and box are disposed such as to limit a radially outward deformation of the lip end. The main shoulder of the pin has a greater radial dimension than said sub shoulder of the pin, and at least the main shoulder surface of the pin is in axial abutment with at least the corresponding main shoulder surface of the box.

A threaded joint for pipes comprises a pin and a box, each having a threaded and unthreaded portion metal contact surface. The unthreaded metal contact portion includes a sealing surface and a shoulder surface, the shoulder surface of the pin located on the pin end surface. A non-contacting region where the pin and the box do not contact each other exists between the sealing surfaces and the shoulder surfaces of the pin and the box. One or more grooves is formed in at least one of the pin and the box shoulder surfaces and extending to the non-contacting region and to the interior of the joint. At least one of the contact surfaces has a solid lubricating coating exhibiting plastic or viscoplastic rheological behavior. A total volume V (mm) of the grooves and coating weight W (g) of the solid lubricating coating satisfy the equation V/W&#x2267;24 (mm/g).

Threaded joint for pipes

A threaded joint for steel pipes comprising a pinhaving a tapered male thread, a tapered sealing surface, and an end shoulder surfaceand a boxhaving correspondingly a tapered female thread, a tapered sealing surface, and a shoulder surfacewhich is capable of easy tightening and has improved air tightness by the sealing surfaces is arranged such that the pin and the box each have a noncontacting region B where the peripheral surfaces of the pin and the box do not contact each other between the sealing surfacesand the shoulder surfacesand. At least a portion of the noncontacting region of the pin adjoining the to end of the pin is a tapered surface portionhaving substantially the same angle of slope as the tapered sealing surface, and the noncontacting region of the box is a substantially cylindrical surface.

A threaded joint for steel pipes constituted by a pin having male threads and a box having female threads is improved with respect to ease of insertion of the pin and galling resistance of the threaded portions. The stabbing flanks of the threads in a complete thread portion of one of the pin and a box has a two-step stabbing shape having a chamfer. The two-step stabbing shape has a stabbing flank angle &#x3b1; of 5-45&#xb0; and a chamfer angle &#x3b2; of 20-60&#xb0;. The ratio h/H of the chamfer height h to the thread height H of the pin is 0.25-0.50, or the ratio of the cross-sectional area of the chamfered portion to the overall cross-sectional area of the stabbing flank is made at least a value corresponding to a chamfer height ratio h/H of 0.25 and at most a value corresponding to a chamfer height ratio of 0.50.

Growing community of inventors

Amagasaki, Japan

Suguru Yamaguchi