LIP-TYPE HIGH-PRESSURE SEAL

摘要

A high pressure shaft seal (10A) for use in a refrigerating machine wherein carbon dioxide is used as a refrigerant in lieu of "Freon". The seal has a sealing lip (24A) made of a non-elastomeric polymer material such as nylon that has a small gas permeability coefficient, a region of the sealing lip brought into contact with a shaft to be sealed being lined with a low friction lining (26A) of polytetrafluoroethylene.The gas barrier sealing lip (24A) of nylon serves to effectively block permeation of carbon dioxide gas under an extremely high pressure of from about 4 MPa to about 12 MPa. The sealing lip (24A) of nylon has a relatively high rigidity but is nevertheless able to resiliently undergo elastic deformation when such a high pressure is applied, to thereby resiliently follow any shaft run-out to exhibit sufficient dynamic and static sealing functions. <IMAGE>