Nippon Kokan Kabushiki Kaisha

Junichiro Takehara

Tadaaki Taira

Toshio Ishihara

Yasuo Kobayashi

Kazuyoshi Ume

A clad steel pipe excellent in corrosion resistance and low-temperature toughness, which comprises a cladding sheet of high corrosion resistant steel and a substrate sheet of low-alloy high-strength steel, the substrate sheet consisting, as the fundamental constituents, essentially of:

Clad steel pipe excellent in corrosion resistance and low-temperature

For producing steel pipe from thick steel plate, an up-set shrinker is employed for reducing and processing an O-shaped pipe-blank in a facility for producing thick wall steel pipe. The up-set shrinker is provided with a plurality of reducing shrinker dies located around the pipe-blank in correspondence to parts other than abutting parts of the edges of the pipe-blank, and with at least one edge processing shrinker die located in correspondence to the butting parts of the edges of the pipe-blank. The edge processing shrinker die is formed at its die surface with a projecting portion over the length of the die. The edge processing shrinker die is actuated independently of the reducing shrinker dies.

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Fukuyama, Japan

Junichiro Takehara