| 摘要 |
A seal for sealing a low pressure area from a high pressure area for containing a process fluid. The high pressure area is located along a rotatable shaft extending from a machine body. The seal (10) includes an outboard seal (12) positioned along the shaft (22), and an inboard seal (14) axially spaced along the shaft (22) from the outboard seal (12). An annular chamber (92) is defined between the inboard seal (14) and the outboard seal (12) for containing a buffer fluid. The inboard seal (14) includes a stationary assembly (16) attached to the machine body (18). The stationary assembly (16) includes a stationary seal ring (24) having a stationary sealing face, and a first secondary seal between the stationary seal ring and the housing. The inboard seal (14) further includes a rotating assembly attached to the shaft (22). The rotating assembly includes a rotating seal ring (78) having a rotating sealing face in sealing relation with the stationary sealing face and a second secondary seal (80) between the rotating seal ring (78) and the shaft. The first and second secondary seals define fluid pressure barriers for causing axial movement of at least a portion of the stationary assembly and maintaining the sealing relation of the rotating and stationary sealing faces when the pressure of the buffer fluid is less than the pressure of the process fluid. <IMAGE> |
