Hitachi, Ltd.

Hitachi Kyowa Kogyo Co., Ltd.

Masayuki Kurihara

Yasumasa Tamai

Yutaka Watanabe

Takao Funamoto

Koichi Kurosawa

Fuminori Ishikawa

Toshimi Matsumoto

Tsutomu Onuma

Akira Onuma

Mitsuo Nakamura

Hiroshi Tsujimura

Hiroo Koide

Choichi Asano

Seiichi Toyoda

A submerged laser beam irradiation equipment provides a high quality submerged laser beam processing of a submerged workpiece using only a small amount of a gas. The submerged laser beam irradiation equipment has: a focus lens for focusing a laser beam; a mirror tube which houses the lens; a first nozzle operating to cover the front end of the mirror tube in an irradiating direction of the laser beam; a skirt portion provided at the front end of the first nozzle for preventing water intrusion thereinto; and a shutter mechanism operable to open and close and provided between said skirt portion and said mirror tube for preventing water intrusion into said mirror tube.

Submerged laser beam irradiation equipment

By applying spot welding along a crack which has occurred in an austenitic stainless steel structure without use of welding material so that spot welds are connected, melting and solidifying of the crack can be achieved, thereby to provide a metal structure which is rich with delta ferrite of the austenitic stainless steel structure or prevent propagation of the crack by enclosing it into the interior of the austenitic stainless steel structure.

Metal member quality improving method by spot welding

Growing community of inventors

Hitachi, Japan

Masayuki Kurihara