Daido Tokushuko Kabushiki Kaisha

Komatsu Corporation

Fuji Valve Co., Ltd.

Nippon Kokan Co., Ltd.

Hitoshi Hayakawa

Yuko Takeuchi

Yoshihisa Kato

Taku Murakami

Masaki Tsuchiya

Masaru Nagata

Kiyoshi Morii

Kazuto Terai

Motoaki Oyama

Akifumi Hoshino

Minoru Yuzuki

F X Terwijn

Shinji Nakayama

Naoki Nishimura

Tooru Fukuda

Yukoh Takeuchi

Yuukou Takeuchi

A metal pipe inner surface weld-mounting apparatus having a monitoring device is constituted by an arm, a horizontal torch, a mirror, a camera and a monitoring device. The arm has a supported base end portion, which is horizontally extended. The horizontal torch is attached to a leading end portion of the arm. The weld-mounting is performed on an inner surface portion of a metal pipe supported rotatably around a horizontally extending axis while at least one of the metal pipe and the horizontal torch is moved in a direction of the axis. The mirror is attached to the leading end portion of the arm. The camera is disposed in a position separated from the mirror for picking up an image of weld-mounting beads in a neighborhood of arc light of the horizontal torch through the mirror. The monitoring device monitors a condition of the weld-mounting.

Internal metal pipe welding apparatus and monitoring system

A multi-layered heat resistant metal tube is disclosed. This tube has excellent anti-coking characteristics and is suitable for use under the conditions where carbon tends to deposit and accumulate thereon due to contacting with hydrocarbons at a high temperature. The tube is made by forming weld-mounted overlaid layer of a Cr&mdash;Ni&mdash;Mo alloy by building-up welding over the inner surface and/or the outer surface of a substrate tube made of a heat resistant metal. The Cr&mdash;Ni&mdash;Mo alloy consists essentially of, by weight %, Cr: 36-49 wt %, Ni: 35-63 wt % and Mo: 0.5-5 wt %. Building-up welding is preferably carried out by PPW (Plasma Powder Welding) in which the filler metal is supplied in the form of powder.

Multi-layered anti-coking heat resisting metal tube and the method for manufacturing thereof

In a method of the present invention for manufacturing a welded clad steel tube, an alloy including a corrosion-resisting or heat-resisting alloy is overlaid on a raw steel tube to manufacture a cold steel tube. Then, a cold or warm working is subjected to the clad steel tube. The clad steel tube is subjected to a heat treatment at a temperature exceeding a recrystallization temperature of the alloy.

Method for manufacturing welded clad steel tube

A compact plasma cutting apparatus suitable for the thermal cutting of concrete structures includes a sealed housing to which a plasma gas is fed under pressure. A metal strip that serves as an outer hollow electrode is bent such that a widthwise section thereof is in circular form, while a metal rod or tube is continuously inserted through a hollow portion of the thus formed outer electrode, with an insulator located between both electrodes. While gas is passed between the inner and outer electrodes, an arc is produced at open ends of both electrodes to generate a plasma gas, which is in turn blown onto a concrete structure for thermal cutting. The formation of both electrodes is effected depending on consumption of the electrodes, thereby carrying out thermal cutting continuously. A high-efficient yet economical cutting method is achieved using the cutting apparatus.

Plasma cutting apparatus for concrete structures

A wear-resistant titanium or titanium-alloy member adapted for use as a poppet valve, rocker arm, etc., of an internal combustion engine, which requires lightness in weight and good wear resistance, and a method for manufacturing the member. The surface of the titanium or titanium-alloy member is given a Vickers hardness number of 390 to 1,200, preferably 400 to 800, and a hardened layer depth of 0.1 to 2.0 mm, preferably 0.3 to 1.5 mm, by being melt-hardened while being supplied with hardening elements.

Wear-resistant titanium or titanium-alloy member and a method for

Growing community of inventors

Aichi, Japan

Hitoshi Hayakawa