公开(公告)号：US11053749B2

公开(公告)日：2021-07-06

申请号：US16328006

申请日：2017-09-13

Applicant: JFE Steel Corporation

Inventor： Takamasa Kawai ,  Taro Kanayama ,  Masaki Yoshikawa ,  Jun Takano ,  Takuya Nagahama

IPC: F16L15/00 ,  E21B17/08 ,  F16L15/04 ,  E21B17/042

Abstract: A threaded joint for oil well steel pipe is provided. The threaded joint includes a pin provided with a male thread, and a box provided with a female thread threadedly engaged with the male thread, and at an outer periphery side sealing portion, a cross-sectional area S1 of the pin at a seal point, and a cross-sectional area S0 of a pipe body portion, which is an unprocessed pin portion, satisfy an expression (S1/S0)×100≥15(%), at an inner periphery side sealing portion, a cross-sectional area S2 of the box at a seal point, and a cross-sectional area S0′ of a pipe body portion, which is an unprocessed box portion satisfy an expression (S2/S0′)×100≥20(%), and a surface area S3 of a contact portion of an intermediate shoulder between thread rows and the cross-sectional area S0 satisfy the expression (S3/S0)×100≥10(%).

公开(公告)号：US10295091B2

公开(公告)日：2019-05-21

申请号：US15111544

申请日：2014-12-18

Applicant: JFE Steel Corporation

Inventor： Masaki Yoshikawa ,  Hiroshi Chikatsune ,  Kazunari Takahashi ,  Takuya Nagahama ,  Jun Takano ,  Masateru Ueta ,  Takamasa Kawai

IPC: F16L25/00 ,  F16L15/00 ,  E21B17/042 ,  F16L15/06

Abstract: A threaded joint is adapted for tubes where the stress or the strain concentration hardly occur at a threaded corner portion of box side even when the threaded joint receives repeated tensile-compressive forces or repeated bending forces. In a radial seal type threaded joint, tensile efficiency TE (%) defined by a ratio Sc/Sp between a cross-sectional area Sc, an area of Critical Cross Section (CCS) including a portion where a tensile stress and a strain become the highest in a tube circumferential cross section of a box and a cross-sectional area Sp of a tube body satisfies formula TE (%)≥2.25×t/ρ+99.9 having a ratio t/ρ between an internal thread height t of the box and a radius of curvature ρ of a corner portion of internally-threaded bottom load surface side.

公开(公告)号：US20190056049A1

公开(公告)日：2019-02-21

申请号：US16077912

申请日：2016-12-16

Applicant: JFE Steel Corporation

Inventor： Takamasa Kawai ,  Taro Kanayama ,  Masaki Yoshikawa ,  Haruhiko Seki ,  Masateru Ueta ,  Jun Takano ,  Tsuyoshi Yoneyama

IPC: F16L15/04

Abstract: Provided is a threaded joint for an oil well tubing which possesses sufficient sealability when the external pressure is applied to the threaded joint by suppressing the plastic deformation of a nose portion and sufficient galling resistance. The sufficient galling resistance is provided by preventing the occurrence of galling at the time of making up the threaded joint during verification test performed in accordance with ISO13679:2002 even when the threaded joint for an oil well tubing has a small thickness. Parameters including sizes of the threaded joint at positions of a seal point and shoulder portions satisfy formula 1 ((Ds12−Ds02)/(D12−D02)≥0.30), formula 2 (tan θ>(ΔD+δ)/{2(Lt−Ls)}), and Ls/Ln is set to 0.2 to 0.6.

公开(公告)号：US20160319966A1

公开(公告)日：2016-11-03

申请号：US15108856

申请日：2014-10-30

Applicant: JFE STEEL CORPORATION

Inventor： Takamasa Kawai ,  Kazunari Takahashi ,  Hiroshi Chikatsune ,  Masaki Yoshikawa ,  Jun Takano ,  Takuya Nagahama ,  Masateru Ueta ,  Tsuyoshi Yoneyama ,  Hideo Sato ,  Haruhiko Seki

IPC: F16L15/04 ,  F16L15/06 ,  E21B17/042 ,  F16L15/00

CPC classification number: F16L15/04 ,  E21B17/042 ,  F16L15/004 ,  F16L15/06

Abstract: A threaded joint for heavy-walled oil country tubular goods can both ensure sealability and prevent galling in a state where a high external pressure is also applied to the threaded joint in addition to a high compressive force. A surface of a pin side forming a seal portion and a surface of a box side forming a seal portion are formed into a convex curved surface and a tapered surface, respectively. A seal thickness ts of the pin is 15 mm or less, a shape parameter ts/D (D: outer diameter of a pin raw pipe portion) is 0.045 or more, and a complete thread length ratio L/t (L: complete thread length of the pin, t: wall thickness of the pin raw pipe portion) is 4.0 or less.

Abstract translation: 用于重型油井筒的螺纹接头除了具有高的压缩力之外，还可以在螺纹接头上施加高的外部压力的状态下确保密封性并防止磨损。 形成密封部的销侧的表面和形成密封部的盒侧的表面分别形成为凸曲面和锥面。 销的密封厚度ts为15mm以下，形状参数ts / D（D：销原料管部的外径）为0.045以上，完全螺纹长度比L / t（L：完全螺纹 销的长度，t：销原料管部的壁厚）为4.0以下。