Vallourec Oil and Gas France

Nippon Steel Corporation

Sumitomo Metal Industries, Inc.

Nippon Steel Sumitomo Metal Corporation

Vallourec & Mannesmann Oil & Gas France

Nof Corporation

Other

Shiseido Company, Limited

Masaaki Sugino

Keita Inose

Yousuke Oku

Suguru Yamaguchi

Miyuki Yamamoto

Michihiko Iwamoto

Shin Ugai

Keiichi Nakamura

Shigeo Nagasaku

Takahiro Hamamoto

Hikari Nakano

Fumio Ota

Eric Verger

Sadao Douchi

Takashi Okada

Tatsuya Yamamoto

Yukihiro Nishikawa

Bertrand Maillon

Claire Patureau

Yasuhiro Yamamoto

Kunio Goto

Masayoshi Sasaki

Gabriel Roussie

Satoshi Maruta

Kazuya Ishii

Daly Daly

Sylvain Beigneux

Jean-Francois Charvet-Quemin

Masahiro Oshima

Emmanuel Varenne

Russell Elder

Pierre Dutilleul

Alan Fothergill

Takahiro Takano

Celine Sches

Xavier Mencaglia

Kuniaki Tsuruoka

Katsutoshi Sumitani

Yoshihiro Ohhata

Benoit Le Chevalier

Corey Dufrene

Takeshi Matsuo

Hideto Yamamoto

Hiroyuki Takeo

Isao Takayanagi

Jean-Pierre Emery

Gabriel Briquet

Jean-François Charvet-Quemin

Benoît Le Chevalier

A threaded connection for pipes includes a pin, a box, a shoulder part plating layer, and a non-shoulder part plating layer. The shoulder part plating layer has an outermost layer formed of a high friction coefficient plating layer, and is arranged on a pin side shoulder part and/or a box side shoulder part. The non-shoulder part plating layer has an outermost layer formed of a low friction coefficient plating layer having a coefficient of friction lower than a coefficient of friction of the high friction coefficient plating layer, and the non-shoulder part plating layer is arranged on at least one of a pin side thread part, a pin side metal seal part, a box side thread part, and a box side metal seal part.

Threaded connection for pipes

A threaded connection for steel pipe is provided in which galling does not easily occur on any of the inner and outer threads. A threaded connection for steel pipeincludes a pinand a box. The pinincludes: a nose; a tapered inner male thread; a tapered outer male thread; a pin inner sealing surface; a pin intermediate shoulder surface; and a pin intermediate sealing surface. The boxincludes: a tapered inner female thread; a tapered outer female thread; a box inner sealing surface; a box intermediate shoulder surface; and a box intermediate sealing surface. Each of the inner male thread, outer male thread, inner female threadand outer female threadincludes a perfect thread portion. Each perfect thread portion includes an inner end located relatively close to the tip of the pinand an outer end located relatively close to the end of the pinopposite to its tip. The threaded connection for steel pipesatisfies the following Expressions (1) and (2):  (1), and  (2).

Threaded connection for steel pipe

In a threaded connection of a two-step thread construction including intermediate shoulder surfaces, a break is prevented near the intermediate critical cross sections upon application of a tensile load, and the intermediate shoulder surfaces are easier to create, thus improving productivity. The outer periphery portion of a pin located between an intermediate shoulder surface of the pin and a second male thread is provided with a circumferential groove including a curved surface smoothly contiguous to the intermediate shoulder surface, thereby mitigating plastic strains generated near the pin intermediate critical cross section PICCS. The inner periphery portion of a box located between an intermediate shoulder surface of the box and a first female thread is provided with a circumferential groove including a curved surface smoothly contiguous to the intermediate shoulder surface, thereby mitigating plastic strains generated near a box intermediate critical cross section BICCS.

Threaded connection

A disclosed threaded connection for steel pipes includes a pin and a box. The pin includes, in order from a front end of the pin toward a pipe body of the pin, an annular shoulder surface, an annular sealing surface located adjacent to the shoulder surface, and a male thread part. The box includes, in order from a pipe body of the box toward a front end of the box, an annular shoulder surface, an annular sealing surface located adjacent to the shoulder surface, and a female thread part. The pin shoulder surface and the box shoulder surface incline from a plane perpendicular to a pipe axis in a direction of screwing the pin. A diameter of an inner circumferential edge of the pin shoulder surface is smaller than a diameter of an inner circumferential edge of the box shoulder surface.

Threaded connection for steel pipes

A two-step threaded connection for steel pipe includes an intermediate seal and intermediate shoulders. A pinhas an inner male-threaded sectionand an outer male-threaded sectionA boxhas an inner female-threaded sectionand an outer female-threaded sectionThe pinhas a pin intermediate critical cross section PICCS located near an end of the first male-threaded sectionThe boxhas a box critical cross section BCCS located near an end of the inner female-threaded sectionand a box intermediate critical cross section BICCS located near an end of the outer female-threaded section The pinand the boxsatisfy the following relationships:PICCSA+BICCSA&#x3e;BCCSA, and0.70&#x2264;PICCSA/BICCSA&#x2264;0.95.

A threaded connection for steel pipe with improved sealing performance is provided. A threaded connection () includes a pin () and a box (). The pin () includes a pin shoulder surface (), a pin sealing surface () and a male thread (). The box () includes a box shoulder surface (), a box sealing surface () and a female thread (). The male thread () and female thread () are constituted by wedge threads. When the connection has been made up, the pin shoulder surface () is in contact with the box shoulder surface (), the stabbing flank and load flank of the male thread () are in contact with the stabbing flank and load flank, respectively, of the female thread (), and the pin sealing surface () is in contact with the box sealing surface (). The shoulder angle is 4&#xb0; or larger. The shoulder angle is the angle formed by each of the shoulder surfaces () with a plane perpendicular to the pipe axis (CL) when the connection is not made up.

A threaded connection with good internal-pressure and external-pressure sealability while preventing galling is provided. A threaded connectionincludes a pinand a box. The pinincludes a pin lip, a pin metal seal, and a cylindrical inner machined surface. The pin metal sealincludes a pin seal taper surfaceand a pin seal curvature surface. The boxincludes a box metal sealparallel to the pin seal taper surface. The pin metal sealsealingly contacts the box metal sealat a seal point SP. The threaded connection satisfies the following expressions, (1) and (2),&#x2003;&#x2003;(1), and&#x3e;1.6&#x2003;&#x2003;(2).L is the length of the pin lip; Lm is the distance between the tip AP of the pin and the end point of the cylindrical inner machined surface; Ls is the distance between the tip AP of the pinand the seal point SP; tb is the wall thickness of the boxas measured at the seal point SP when the connection is made up; and tp is the wall thickness of the pinas measured at the seal point SP.

A threaded connection for a steel pipe includes a box which is an opening end of a second pipe and a truncated cone shaped pin which is an end of a first pipe and is inserted into the box, wherein the pin includes a male thread portion which is a tapered thread and a seal portion which includes a tapered surface, the box includes a female thread portion which is a tapered thread and a seal portion which includes a tapered surface, and in a state before make-up between the pin and the box, a minimum diameter of the tapered surface of the pin is smaller than a maximum diameter of the tapered surface of the box.

A threaded connection includes a first and a second tubular component made up one with the other. A male element of the first component includes, on its external peripheral surface, a male inner lip including an inner mg with a minimum thickness Epi and a male threaded zone. One inner end of the male threaded zone is at a non-zero axial distance (Li) from a male distal end. A female element of the second component includes, in succession over its internal peripheral surface, a female inner recess disposed facing the male inner lip and a female threaded zone, such that in the made up position of the connection, a radial clearance subsists between the male inner ring and the female inner recess and an internal seal is formed locally between the male inner lip and the female inner recess. The connection is such that 10%&#x2264;Epi/Li.

Threaded connection for tubular component

The disclosed threaded connection for steel pipes includes a pin including a tapered male thread part and a shoulder part, and a box including a tapered female thread part and a shoulder part. In a made up state in which the shoulder parts are in contact with each other, clearances are provided between crests of the male thread part and roots of the female thread part. At a longitudinal section that includes a pipe axis of the threaded connection, the crests of the male thread part are formed in a convex curve that is tangent to both first corner portions which are formed in an arc that connect the crests and load flanks, and second corner portions which are formed in an arc that connect the crests and stabbing flanks. A solid lubricant coating is provided on the surface of the male thread part.

A threaded connection for steel pipes having improved sealing performance is provided. A threaded connection () for steel pipes includes a pin () and a box (). The pin () includes a nose (), a pin shoulder surface (), a pin sealing surface () and a male thread (). The box () includes a box shoulder surface (), a box sealing surface () and a female thread (). When the position of the portion of the pin sealing surface () that first contacts the inner periphery of the box () during make-up defines a seal position (P), the distance between the seal position (P) and the end of the male thread () adjacent to the pin sealing surface () as measured in the pipe-axis direction is denoted by x, and the distance between the tip of the pin () and the end of the male thread () adjacent to the pin sealing surface () as measured in the pipe-axis direction is denoted by L, then, x/L is not smaller than 0.4 and not larger than 0.55.

A threaded connection for steel pipe is provided that improves its internal-pressure sealability while maintaining the high external-pressure sealability of a threaded connection having a nose used in a steel pipe with large diameter and large wall thickness. In a threaded connection for connecting steel pipe bodies each having an outer diameter equal to or larger than 7 inches and a wall thickness equal to or larger than 0.7 inches, Expression (1) in the description is satisfied and t/t&#x3e;1.4, where &#x3b4; [mm] is the clearance between the outer surface of the pin and the inner surface of the box upon make-up as measured at the borderline between the pin taper surface and the pin round surface, D [inch] is the outer diameter of the steel pipe body, t [inch] is the wall thickness of the steel pipe body, L [mm] is the distance between a pivot point, which is a position, in the region of contact between the pin sealing surface and the box sealing surface, which is closest to the tip of the pin, and the tip of the pin upon make-up as measured along the pipe-axis direction, t[mm] is the wall thickness of the pin as measured at the pivot point, and t[mm] is the wall thickness of the box as measured at the pivot point.

A threaded connection for steel pipes is provided that exhibits improved sealability against the external pressure while maintaining the sealability against the internal pressure. A threaded connection for steel pipes includes a pin and a box. The pin includes a nose, a tapered inner male thread, a tapered outer male thread, a pin inner sealing surface, a pin intermediate shoulder surface, a pin intermediate sealing surface, and a pin annular portion. The box includes a recess corresponding to the nose, a tapered inner female thread, a tapered outer female thread, a box inner sealing surface, a box intermediate shoulder surface, a box intermediate sealing surface, and a box annular portion. The threaded connection satisfies expressions (1) and (2), provided below. &#x3b1;is a taper slope of the inner male thread, and &#x3b1;is a taper slope of the outer male thread.  In expression (2), Lis a distance between the tip of the pin and the pin intermediate shoulder surface as measured along the pipe-axis direction when the pin and box have not been made up, and Lis a distance between the box intermediate shoulder surface and the tip of the box as measured along the pipe-axis direction when the pin and box have not been made up.

A threaded connection for steel pipe is provided that prevents galling on the sealing surfaces during make-up while providing high sealing performance after completion of make-up. The pin () includes a nose () including a pin taper guide surface () and a pin sealing surface () including a taper surface (). The box () includes a nose-receiving portion () including a box taper guide surface (), a box sealing surface () including a taper surface (), and a buffer surface (). The taper angle of the taper surfaces () includes a second taper angle larger than the taper angle of the taper guide surfaces (). The threaded connection () is constructed so as to satisfy Dp2&#x3e;Db2&#x3e;Dp1 and Lb2&#x3e;Lp2. The buffer surface (), located between the box taper guide surface () and taper surface (), has a length of 0.75 mm or larger, and is located outward of an imaginary plane (V) determined along radial directions.

High sealing performance is provided in a threaded connection used for pipes for oil wells with large wall thickness and with a connection efficiency smaller than 1. A threaded connection () connects pipes for oil wells (). The threaded connection () includes two pins () and a tubular coupling. Each of the pins () is provided on an end of the pipe for oil wells () and is in continuity with the pipe body (), which has a wall thickness not smaller than 12 mm. The coupling () includes two boxes () and a recess portion (). The box () is provided on both ends of the coupling (). The recess portion () has a length not smaller than 10 mm. The threaded connection () has a connection efficiency smaller than 1. When the wall thickness of the pipe body () is expressed as t, the wall thickness and length of the recess portion () are expressed as tand 2&#xd7;L, respectively, and the length of each of the boxes () is expressed as L, and if the following expressions (1) and (2) define T and L, then, T and L satisfy the following expression (3): 

Threaded connection for oil well

Growing community of inventors

Nishinomiya, Japan

Masaaki Sugino