| 摘要 |
1,132,698. Shaft seals. ETABLISSEMENTS POMPES GUINARD S.A. 1 Dec., 1965 [4 Dec., 1964], No. 51006/65. Heading F2B. [Also in Divisions F1 and H2] In a liquefied gas pump, a sealing passage, formed between members 10, 11, limits leakage from the pump suction chamber 5a to a gastight chamber 15a filled with the gas of the liquid being pumped or with an inert gas. Heat-insulating material 7c is provided. The chamber 15a is formed by a housing 15 as shown, or by an extended electric driving motor housing. The gas in the chamber 15a is heated by the electric motor and may be cooled by liquid circulated through an annular jacket 19. The level of the liquefied gas normally exists between a conduit 7a and an expansion tube 8. Liquid leakage flowing through the sealing passage to the chamber 15a is heated and thereby gasifies. In an alternative embodiment, Fig. 3 (not shown), a free end of a pump shaft extends into a gas-tight bearing housing which has an intermediate chamber (26) into which leakage past a plain seal (25) around the shaft is discharged. The leakage is gasified by heat from the ambient or a heated fluid via a jacket surrounding the intermediate chamber. |
