Mitsubishi Heavy Industries Limited

Nippon Welding Rod Co., Ltd.

The Kansai Electric Power Co., Inc.

The Tokyo Electric Power Company, Incorporated

Chubu Electric Power Company, Inc.

The Chugoku Electric Power Co., Inc.

Tohoku Electric Power Company, Inc.

Electric Power Development Co., Ltd.

Kyushu Electric Power Co., Inc.

Hokkaido Electric Power Company, Inc.

Shikoku Electric Power Co., Inc.

Hokuriku Electric Power Company

The Japan Atomic Power Company

Seiji Asada

Teiichiro Saito

Masahiko Toyoda

Seiichi Kawaguchi

Norihito Ogawa

Kenji Kawasaki

Takashi Miyake

Yusuke Sano

Takahiro Ota

Koji Okimura

Kazuhiko Kamo

Tamao Takatsu

Nobutaka Nakajima

Hironori Onitsuka

Itaru Muroya

Katsuji Dambayashi

Akira Konishi

Yoshihiro Tada

Tetsuya Sango

Kazuhiro Wakabayashi

Provided is a high Cr Ni-based alloy welding wire with which tensile strength and weld cracking resistance of a welded portion, the integrity of the microstructure of a welded metal, and inhibition of scale generation are improved. The high Cr Ni-based alloy welding wire is configured to have an alloy composition comprising, by mass, C: 0.04% or less, Mn: 7% or less, Fe: 1 to 12%, Si: 0.75% or less, Al: 0.01 to 0.7%, Ti: 0.01 to 0.7%, Cr: 25.0 to 31.5%, Ta: 1 to 10%, and Mo: 1 to 6%, and as inevitable impurities, Ca+Mg: less than 0.002%, N: 0.1% or less, P: 0.02% or less, O: 0.01% or less, S: 0.0015% or less, H: 0.0015% or less, Cu: 0.08% or less, and Co: 0.05% or less, and the balance: Ni. Then, the high CrNi-based alloy welding wire is configured such that the contents of S, Ta, Al, and Ti satisfy the following relation (1) and the contents of Ta, Mo, and N satisfy the following relation (2):12000S+0.58Ta&#x2212;2.6Al&#x2212;2Ti&#xa3;19.3&#x2003;&#x2003;(1)Ta+1.6Mo+187N5.7&#x2003;&#x2003;(2).

High Cr Ni-based alloy welding wire, shielded metal arc welding rod, and weld metal formed by shielded metal arc welding

An object is to provide a method and an apparatus for improving a residual stress in a tubular body, which are enabled to improve the residual stress reliably by clearly defining controlling rage for treatment conditions without depending on an installation state and configuration of the tubular body. When a cylindrical tubular body () is improved in its residual stress by locally irradiating an outer-circumferential surface of a welded portion (C) of the tubular body () with laser beams () and by moving an irradiation area (s) in an circumferential direction, a plurality thermocouples () are installed on the tubular body () to be improved, a temperature history of the outer surface of the tubular body () by the irradiation of the laser beam () is managed by measuring the temperature history itself.

Method for improving residual stress in tubular body

The present invention provides a high Cr Ni-based alloy filler material of which weld cracking resistance can sufficiently be increased by suppressing generation of scales, and a welding rod for shielded metal arc welding that exhibits sufficiently increased weld cracking resistance. The high Cr Ni-based alloy filler material comprises, in percent by weight, C: 0.04% or less, Si: 0.01 to 0.5%, Mn: 7% or less, Cr: 28 to 31.5%, Nb: 0.5% or less, Ta: 0.005 to 3.0%, Fe: 7 to 11%, Al: 0.01 to 0.4%, Ti: 0.01 to 0.45%, V: 0.5% or less, and, as inevitable impurities, P: 0.02% or less, S: 0.015% or less, O: 0.01% or less, N: 0.002 to 0.1%, and the balance: Ni.

High Cr Ni-based alloy filler material and welding rod for shielded metal arc welding

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Tokyo, Japan

Seiji Asada