Kabushiki Kaisha Toshiba

The Japan Steel Works, Ltd.

Joji Kaneko

Masayuki Yamada

Osamu Watanabe

Shigeru Suzuki

Tsukasa Azuma

Ryuichi Ishii

Makoto Takahashi

Yomei Yoshioka

Yoichi Tsuda

Masataka Kikuchi

Takao Inukai

Itaru Murakami

Kenichi Okuno

Satoru Asai

Reki Takaku

Satoru Ohsaki

Akihiro Taniguchi

Kazuhiro Miki

Koji Kajikawa

Tetsuya Yamanaka

Liang Yan

Kazuhiro Wada

Natsuki Ishibashi

A low alloy steel ingot contains from 0.15 to 0.30% of C, from 0.03 to 0.2% of Si, from 0.5 to 2.0% of Mn, from 0.1 to 1.3% of Ni, from 1.5 to 3.5% of Cr, from 0.1 to 1.0% of Mo, and more than 0.15 to 0.35% of V, and optionally Ni, with a balance being Fe and unavoidable impurities. Performing quality heat treatment including a quenching step and a tempering step to the low alloy steel ingot to obtain a material, which has a grain size number of from 3 to 7 and is free from pro-eutectoid ferrite in a metallographic structure thereof, and which has a tensile strength of from 760 to 860 MPa and a fracture appearance transition temperature of not higher than 40&#xb0; C.

Low alloy steel for geothermal power generation turbine rotor, and low alloy material for geothermal power generation turbine rotor and method for manufacturing the same

A steam turbine rotor having a combination of at least one of a high pressure rotor, an intermediate pressure rotor and a low pressure rotor, which are each formed from a metal material of different chemical composition and welded together by means of welding.

Steam turbine rotor and manufacturing method thereof

Growing community of inventors

Tokyo, Japan

Joji Kaneko