摘要 |
The shaft seal assembly of cartridge designed for sealing shafts entering or exiting enclosed vessels. The enclosed vessels may have a pressure different from the atmospheric pressure and the seal will normally prevent leakage from or into the vessel. The seal is accomplished by having a plurality of fluid pressures presented to different faces or portions of the seals. Utilization of these pressures provides a seal between the faces of the rotating parts and the stationary parts of the seal with a minimum of friction. This reduced friction is a result of some amount of air movement between the sealing faces. This air movement into and out of the seal, resulting from fluid pressure different- ials, will also carry away any contaminants that may get into the seal, either to the ambient atmosphere or to a recovery system. The seal is designed to accept axial and radial shaft displacement while maintaining a positive seal between the vessel and the atmosphere. The seal of this invention inclu- des force loading of the rotating members toward the station- ary members, each member with its own sealing face. The force of the loading means is modified by utilization of a first pressure to decrease the loading force and a second fluid pressure proportionate to the first fluid pressure applied to increase the loading force. The first and second fluid press- ures provide a barrier to the flow of materials in either dir- ection through the seal. The rotating members are driven by drive rings which also act as sealing members along the shaft. 21
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