Mitsubishi Heavy Industries Limited

Nippon Welding Rod Co., Ltd.

Mitsubishi Hitachi Power Systems, Ltd.

Seiichi Kawaguchi

Kenji Kawasaki

Teiichiro Saito

Masahiko Toyoda

Seiji Asada

Norihito Ogawa

Shin Nishimoto

Takashi Miyake

Yusuke Sano

Ryuichi Yamamoto

Tamao Takatsu

Nobutaka Nakajima

Akira Konishi

Katsuji Dambayashi

Tetsuya Sango

Yoshihiro Tada

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

A back-shielded welding method according to the present invention includes communicating a front surface-side and a back surface-side of two welding base materials () with each other in the welding base materials () that abut against each other; forming notched portions () in abutting edge portions () of two welding base materials () in such a manner that a slit-shaped gas supply opening () is formed to extend along a forming direction of a welding bead; forming the gas supply opening () with the notched portions () by abutting the abutting edge portions () of the welding base materials () against each other and temporarily fixing the abutting edge portions (); and forming the welding bead while supplying an inert gas via the gas supply opening (), and blocking the gas supply opening () by the welding bead.

Back-shielded welding method and welded structure using the same

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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Hyogo, Japan

Seiichi Kawaguchi