Patent ID: 7055824

Claim:
A method of sealing a refrigerating system having a housing and a shaft, said method comprising providing carbon dioxide gas in the refrigerating system as a refrigerant filled at a pressure of 4–12 MPa; establishing a fluid seal between said housing and said shaft rotating relative to said housing; providing a lip-type seal in the refrigerating system, said seal having an annular sealing lip made from a non-elastomeric, polymer material, said polymer material being a gas barrier material impervious to carbon dioxide gas at said pressure of 4–12 MPa and said polymer material having a gas permeability coefficient of less than 1.0×10 −13 (cm 3 ·cm/cm 2 ·sec·Pa) for carbon dioxide gas at a pressure of 4 MPa; lining an inner circumferential face of said sealing lip with a low friction lining; installing said lip-type seal between said shaft and said housing in such a manner that only said low friction lining is brought into contact with said shaft; and, applying a carbon dioxide gas pressure of 4–12 MPa to a fluid side of said seal as said shaft and said housing are rotated relative to each other to thereby cause said sealing lip to resiliently undergo elastic deformation to cause said low friction lining to resiliently follow any shaft run-out under action of high pressure gas, while substantially preventing permeation of gas by the gas barrier nature of said sealing lip.