The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 11, 1989
Filed:
Nov. 06, 1985
Kenya Ohashi, Hitachi, JP;
Takashi Honda, Katsuta, JP;
Yasumasa Furutani, Katsuta, JP;
Eizi Kashimura, Naka, JP;
Akira Minato, Hitachi, JP;
Katsumi Ohsumi, Hitachi, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
The present invention is concerned with a method of reducing radioactivity in a nuclear plant by preliminarily forming oxide films on the surfaces of metallic structural members to be in contact with high-temperature and high-pressure reactor water containing radioactive substances before said metallic members are exposed to said reactor water. The method is characterized by the steps of subjecting said structural members to a first-step oxidation treatment of heating said structural members in an environment of a high temperature, and further subjecting the thus treated structural members to a second step oxidation treatment of heating said treated structural members in an environment having a higher oxidizing capacity than that of said environment in said first-step oxidation treatment to form a denser oxide film than an oxide film obtained in said first step oxidation treatment. According to the present invention, radioactivity in the nuclear plant can be reduced remarkably.