Nippon Steel Corporation

Nippon Steel Sumitomo Metal Corporation

Other

Nippon Steel Welding Products and Engineering Co., Ltd.

Nobuo Mizuhashi

Hideki Hamatani

Shinji Kodama

Kazuto Yamamoto

Takao Miura

Noboru Hasegawa

Yasushi Hasegawa

Shuichi Ueno

Toshio Fujita

Hitoshi Asahi

Fuminori Watanabe

Katsuhiro Minamida

Hisashi Naoi

Yasushi Ishikawa

Nobuo Araki

Hideo Takafuji

Masahiro Ohgami

Manabu Mizumoto

Takeshi Fukui

Shunichi Kikuta

Masao Kamada

Michimasa Mukai

Takashi Miyakawa

Kenichi Asai

Michitoshi Tanimoto

Seiji Hashimoto

Takeji Kagami

Toshisuke Fukami

Yoshifumi Karube

Sunao Takeuchi

Kunihiko Hatabara

Iwao Yamada

Takumi Nakamura

Hiroya Haga

Tomohiro Nakaji

Yoji Chatani

Kimiharu Tanaka

Takuya Asano

Kazumoto Tsukakoshi

Takashi Motoyoshi

An electric resistance welding operation management device manages a welding operation during manufacture of electric resistance welded steel pipe, in which heat is input to a steel plate, that is being conveyed along a specific conveyance direction and formed into a circular tube shape while pressing side faces of the metal plate with a pair of squeeze rolls, to weld together two circumferential direction edge portions of the metal plate converging in a V-shape. The electric resistance welding operation management device includes an image input section that inputs plural images and each including a Vee convergence region of the steel plate. The electric resistance welding operation management device includes a welding point position derivation section that derives the position of a welding point.

Electric resistance welding operation management device, electric resistance welding operation management method, and computer program

An operation management device performs an operation management for electric resistance welding in which a strip-shaped metal plate is formed to have a cylindrical shape in such a manner that both end portions of the metal plate gradually face each other while the metal plate is conveyed, and a Vee convergence section, which is a portion at which both of the end portions butt against each other while facing each other, is welded. Furthermore, the operation management device includes: a measuring unit that measures a distance L [mm] between a first Vee convergence point at which both of the end portions of the metal plate geometrically come into contact with each other and a second Vee convergence point that is a contact point of both of the end portions of the metal plate, and a Vee convergence angle &#x3b8;[&#xb0;] at the first Vee convergence point on the basis of an image of an area including the Vee convergence section; and a determining unit that determines whether or not the distance L [mm] and the Vee convergence angle &#x3b8;[&#xb0;] satisfy the following equation (1).(&#x3b8;/&#x3b8;)&#x2266;35&#x2003;&#x2003;(1)

Operation management device, operation management method, and operation management program for high-frequency resistance welding and induction welding

The present invention provides a method of production of electric resistance welded steel pipe able to stably reduce weld defects due to oxides by firing plasma and furthermore able to reduce plasma jet noise and comprises shaping steel plateinto a tube and electric resistance welding the abutting end facesduring which blowing on at least the abutting end facesin the regionat the welding upstream side from the weld pointwhere the temperature becomes 650&#xb0; C. or more a reducing high temperature (pseudo) laminar plasma obtained by applying voltage to a reducing gas containing Hgas: 2 to 50 vol % to which is added a balance of Ar gas alone or a mixed gas of Ar gas to which Ngas, He gas, or both are added. At that time, it is preferable to make the applied voltage over 120V and the make the plasma blowing conditions satisfy the following formula (1). 

Method of production of electric resistance welded steel pipe and high Si or high Cr electric resistance welded steel pipe

Disclosed are a weld joint and a stainless steel-based weld metal composition for the weld joint. The composition and weld joint made therefrom are suitable for welding a zinc-based alloy coated steel sheet. The weld is excellent in corrosion resistance and liquid-metal embrittlement crack resistance. This is accomplished by inhibiting liquid-metal embrittlement cracks of the stainless-steel-based weld metal when the zinc-based alloy coating steel sheet is welded using the stainless-steel-based weld metal. The weld joint comprises a welded portion of weld metal made of stainless-steel-based components, the weld metal containing in mass percent (%): C: 0.01-0.1; Si: 0.1-1; Mn: 0.5-2.5; Ni: 5-11; and Cr: 17-25, and the balance being iron and residual impurities, wherein the following expression are met: &#x2212;0.81&#xd7;Cr equivalent+23.2&#x2266;Ni equivalent&#x2266;0.95&#xd7;Cr equivalent&#x2212;8.1 . . . (1); Ni equivalent=Ni+30&#xd7;C+0.5&#xd7;Mn+30&#xd7;N . . . (2); Cr equivalent=Cr+Mo+1.5&#xd7;Si . . . (3).

Weld joint formed with stainless steel-based weld metal for welding a zinc-based alloy coated steel sheet

Martensitic heat-resisting steel excellent in HAZ-softening resistance

Methods for manufacturing tubes filled with powdery and granular

A high-frequency electric resistance welding method combined with the irradiation of a laser beam in which a workpiece is continuously fed and opposed edges of the workpiece are formed into a wedge shape by causing them to converge as they are butted against each other, and the butted edges are melted by heating them with high-frequency resistance heating and a laser beam, to weld the butted edges. The laser beam is projected against the range of over 30% and below 80% of the thickness of the butted edges including the central portion of the thickness to melt the butted edges by the combined heating action of the laser beam and high-frequency current. The corners are heated and melted by means of high-frequency electric resistance heating, so that the butted edges of the workpiece can be melted uniformly through the entire range of thickness.

High-frequency electric resistance welding method using irradiation with

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Tokyo, Japan

Nobuo Mizuhashi