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:
Jun. 04, 2002
Filed:
Mar. 10, 2000
Hideaki Orikasa, Chiyoda, JP;
Hideto Nogiwa, Tsukuba, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A shaft seal system prevents working gas in a centrifugal compressor from leaking outside from the compressor. The shaft seal system is of an oil film seal type and located in the compressor in which a plurality of centrifugal impellers are fitted on a single rotary shaft and are adapted to be rotated at a high speed. The system has two kinds of seal rings, that is, an atmospheric side seal ring and a gas side seal ring, which are loosely fitted in a casing in which bearing for rotatably journalling the rotary shaft are incorporated. A sealing sleeve shrinkage-fitted on the rotary shaft is arranged on the inner diameter side of the two kinds of seal rings. The rotary shaft is formed in its center axial part thereof with a bore extending from a suction side end to a position where the oil film seal is arranged, and a plurality of oil feed holes extending through the rotary shaft from the bore to the outer periphery of the rotary shaft. Seal oil is fed from the suction side of the rotary shaft into clearances between the two kinds of seal rings and the sealing sleeve so as to prevent working gas compressed in the centrifugal compressor from leaking outside from the compressor, and to cool the shaft seal which has been heated up to a high temperature by friction heat with the seal oil.