公开(公告)号：US20190186655A1

公开(公告)日：2019-06-20

申请号：US16331235

申请日：2017-08-31

Applicant: JFE STEEL CORPORATION

Inventor： Shinsuke IDE ,  Akihide MATSUMOTO ,  Atsushi MATSUMOTO ,  Takatoshi OKABE

IPC: F16L9/17 ,  B23K11/00 ,  B23K11/02 ,  B23K11/093 ,  B32B1/08 ,  B32B15/01 ,  C22C38/50 ,  C22C38/48 ,  C22C38/44 ,  C22C38/42 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00 ,  C21D9/08 ,  C22C19/05 ,  C22F1/10

CPC classification number: F16L9/17 ,  B21C37/08 ,  B23K11/0006 ,  B23K11/02 ,  B23K11/0935 ,  B23K13/00 ,  B23K13/06 ,  B23K2101/10 ,  B23K2103/05 ,  B32B1/08 ,  B32B15/011 ,  B32B15/015 ,  B32B2597/00 ,  C21D9/08 ,  C21D9/085 ,  C21D9/50 ,  C22C19/056 ,  C22C38/00 ,  C22C38/001 ,  C22C38/002 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/42 ,  C22C38/44 ,  C22C38/48 ,  C22C38/50 ,  C22C38/60 ,  C22F1/00 ,  C22F1/10

Abstract: Provided is an electric resistance welded clad steel pipe or tube in which a region where solidification microstructure is formed, i.e. a region in a weld particularly having significant influence on properties, is reduced without impairing its function as a clad pipe or tube. An electric resistance welded clad steel pipe or tube comprises: a first layer made of carbon steel or low-alloy steel as base metal; and a second layer placed on one surface of the first layer, and made of stainless steel or a nickel-containing alloy as cladding metal, wherein the base metal is not exposed at a cladding metal-side surface of the electric resistance welded clad steel pipe or tube in a weld, and no solidification microstructure is contained in each of circular sections of 0.1 mm in radius respectively centered at specific three positions in a plane perpendicular to a pipe or tube longitudinal direction.

公开(公告)号：US20190390311A1

公开(公告)日：2019-12-26

申请号：US16480803

申请日：2017-12-14

Applicant: JFE STEEL CORPORATION

Inventor： Akihide MATSUMOTO ,  Hiroshi NAKATA ,  Shunsuke TOYODA

IPC: C22C38/58 ,  C22C38/02 ,  C22C38/06 ,  C22C38/42 ,  C22C38/44 ,  C22C38/46 ,  C22C38/48 ,  C22C38/50 ,  C21D9/08 ,  C21D9/46 ,  C21D8/02

Abstract: There is provided a hot-rolled steel sheet suitable for manufacturing an electric resistance welded steel tube, having workability necessary for roll forming and high yield strength, for coiled tubing without performing whole-tube quenching treatment and reheating-tempering treatment after electric resistance welding. The steel sheet includes, by mass %, C, Si, Mn, P, S, Al, Cr, Cu, Ni, Mo, Nb, V, Ti, and N contained at a specific content. The steel sheet has a microstructure containing 3% to 20% martensite and 10% or less retained austenite on a volume fraction basis, the remainder being bainite. The yield strength is set to 600 MPa or more, the tensile strength is set to 950 MPa or more, and the uniform elongation is set to 7.0% or more.

公开(公告)号：US20190184437A1

公开(公告)日：2019-06-20

申请号：US16331222

申请日：2017-08-31

Applicant: JFE STEEL CORPORATION

Inventor： Takatoshi OKABE ,  Atsushi MATSUMOTO ,  Shinsuke IDE ,  Akihide MATSUMOTO

IPC: B21C37/08 ,  B23K13/06 ,  C21D9/08 ,  C21D9/50 ,  C22C38/06 ,  C22C38/38

CPC classification number: B21C37/08 ,  B23K13/00 ,  B23K13/06 ,  C21D9/08 ,  C21D9/50 ,  C22C38/00 ,  C22C38/06 ,  C22C38/38

Abstract: Provided is a clad welded pipe or tube that has improved pipe or tube mechanical properties by reducing the width of a weld without its function as a clad pipe or tube being impaired. A clad welded pipe or tube comprises: a first layer made of base metal; and a second layer placed on one surface of the first layer, and made of first cladding metal that is a material different from the base metal, wherein a pipe or tube circumferential length L1 of weld metal at a pipe or tube inner surface and a pipe or tube circumferential length L2 of the weld metal at a pipe or tube outer surface in a weld are each 0.0010 mm or more and 1.0 mm or less, and the base metal is not exposed at a first cladding metal-side surface of the clad welded pipe or tube in the weld.

公开(公告)号：US20220168795A1

公开(公告)日：2022-06-02

申请号：US17434659

申请日：2020-02-21

Applicant: JFE STEEL CORPORATION

Inventor： Akihide MATSUMOTO ,  Atsushi MATSUMOTO ,  Shinsuke IDE ,  Takatoshi OKABE

IPC: B21D41/02 ,  B21D26/041 ,  B21D26/043

Abstract: A metal pipe having an outer diameter of 150 mm to 3,000 mm and a wall thickness of 2 mm to 50 mm, and a method for manufacturing the same. The method includes a pipe-end-portion expansion step of expanding pipe end portions that are located at both ends of a mother pipe and an internal pressure application step that is performed after the pipe-end-portion expansion step and in which the mother pipe is expanded by applying an internal pressure, p, to the entire interior of the mother pipe until the internal pressure, p (MPa), that corresponds to changes in an axial compression amount s (mm), the axial compression amount, s, representing an amount of compression in a pipe axial direction against pipe extreme ends which are the both ends of the mother pipe, becomes a preset maximum internal pressure pmax (MPa), and p and s satisfy a specified formula.

公开(公告)号：US20190390296A1

公开(公告)日：2019-12-26

申请号：US16480799

申请日：2017-12-14

Applicant: JFE STEEL CORPORATION

Inventor： Akihide MATSUMOTO ,  Hiroshi NAKATA ,  Shunsuke TOYODA

IPC: C21D9/50 ,  C21D9/08 ,  C21D8/10 ,  C21D6/00 ,  C22C38/58 ,  C22C38/50 ,  C22C38/48 ,  C22C38/46 ,  C22C38/44 ,  C22C38/42 ,  C22C38/06 ,  C22C38/02 ,  C22C38/00

Abstract: There is provided an electric resistance welded steel tube having a yield strength of 896 MPa or more, and excellent low-cycle fatigue resistance, for coiled tubing without performing whole-tube quenching treatment and reheating-tempering treatment after performing electric resistance welding and a method for manufacturing the same. The steel tube includes, by mass %, C, Si, Mn, P, S, Al, Cr, Cu, Ni, Mo, Nb, V, Ti, and N at a specific content. The steel tube has a microstructure that contains 2% to 10% retained austenite and 20% or less martensite on a volume fraction basis, and the remainder being bainite. The yield strength is set to 896 MPa or more and the uniform elongation is set to 9.0% or more.