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:
May. 27, 1997
Filed:
Oct. 26, 1995
Kikuo Takeshima, Hitachi, JP;
Shin Kumagai, Ibaraki-ken, JP;
Masato Koshiishi, Takahagi, JP;
Yositeru Chiba, Hitachi, JP;
Hitachi, Ltd., Tokyo, JP;
Hitachi Kyowa Kogyo Co., Ltd., Ibaraki-ken, JP;
Abstract
Hard facing layers provided on engagement portions of a valve body and engagement portions of a valve box of a valve apparatus, consisting of cobalt-free Ni-base alloys. One of the Ni-base alloys for the hard facing layers comprises not more than 15% Fe and less than 2% W (tungsten), and the other comprises more than 15% Fe. More specifically, one of the cobalt-free Ni-base alloys essentially consists of, by weight, 15 to 20% Cr, 5 to 10% Si, 10 to 15% Fe, less than 2% W, and the balance of Ni and unavoidable impurities, and has a Vickers hardness (Hv) 510 to 630, and the other essentially consists of, by weight, 5 to 15% Cr, 5 to 10% Si, more than 15% and not more than 30% Fe, 1 to 4% W, and the balance of Ni and unavoidable impurities, and has a Vickers hardness (Hv) 400 to 470. The valve apparatus of the invention is suitably installed in a water pipe line which communicates with a nuclear reactor.