SHAFT SEAL STRUCTURE FOR TRANSMISSION EXPANDER OR TRANSMISSION COMPRESSOR, AND TRANSMISSION EXPANDER OR TRANSMISSION COMPRESSOR THEREWITH

摘要

PROBLEM TO BE SOLVED: To provide an improved shaft seal structure capable of protecting a shaft seal portion from corrosion by reducing the amount of shut-off gas and its leakage.;SOLUTION: This shaft seal structure for a transmission expander or a transmission compressor rotating in a casing 20 and comprising a wheel 1 loosely disposed on a shaft 4, is composed of a seal device 10 having a sealing tip 15 disposed on a hub 5 of the wheel 1, and the sealing tip is surrounded by a fixed seal ring 11. The tip 15 is disposed in three sealed sections, here, annular chambers 12, 12' are respectively disposed between two sealed sections. The annular chamber 12 directed to an internal space of the transmission expander or compressor comprises shut-off gas supply piping, and a pressure of the shut-off gas is higher than a pressure of the internal space of the transmission expander or compressor. The annular chamber 12' at a farther side with respect to the internal space of the transmission expander or compressor comprises a shut-off gas draft portion.;COPYRIGHT: (C)2007,JPO&INPIT