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:
Dec. 15, 2009
Filed:
Jul. 06, 2006
Masahiko Arai, Hitachinaka, JP;
Hirotsugu Kawanaka, Hitachi, JP;
Hiroyuki Doi, Tokai, JP;
Kenichi Murata, Hitachi, JP;
Hajime Toriya, Hitachi, JP;
Masahiko Arai, Hitachinaka, JP;
Hirotsugu Kawanaka, Hitachi, JP;
Hiroyuki Doi, Tokai, JP;
Kenichi Murata, Hitachi, JP;
Hajime Toriya, Hitachi, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A pipe for a steam turbine is formed of a centrifugal casting material to achieve resistance against higher temperatures and improve reliability of the pipe by employing, as a pipe material, a centrifugal casting material normalized to contain uniform and finer crystal grains. The centrifugal casting material is made of steel having a columnar structure in the radial direction with the crystal grain size number of 5 or more in a plane perpendicular to the radial direction. The steel includes 0.05-0.5% by mass C, not more than 1.0% Si, 0.05-1.5% Mn, 0.01-2.5% Ni, 8.0-13.0% Cr, 0.05-2.5% Mo, not more than 3.0% W, 0.05-0.35% V, 0.01-0.5% Nb, not more than 5% Co, 0.01-0.1% N, not more than 0.03% B, and not more than 0.05% Al.