| 摘要 |
A mechanical seal for providing fluid sealing between a housing and a rotatable shaft includes a first seal ring having a first seal face and a second seal ring having a second seal face. An opening force is developed between the first and second seal faces that inhibits contact between the seal faces. The seal further includes a system for regulating the opening force on the seal face as a function of the difference between the pressure of the fluid introduced between the seal faces, i.e., the barrier fluid, and the pressure of the process fluid. The seal also includes seal faces that are configured to produced a primarily hydrostatic fluid force between at least a portion of the first portion of the first seal face and at least a portion of the second seal face. In addition, the seal faces are configured to produce a hydrodynamic fluid force and a hydrostatic fluid force between at least a portion of the second portion of the first seal face and at least a portion of the second seal face. A secondary sealing assembly, and first and second seal rings each having a seal face, also form part of the seal. The secondary sealing assembly provides fluid sealing between the seal rings and the gland assembly. The secondary sealing assembly includes a compression member having a front surface and a rear surface, a resilient member positioned between the rear surface of the compression member and the inner surface of the gland assembly for axially biasing said compression plate, and a sealing member interposed between the front surface of the compression member and the rear surface of the first seal ring. Either the rear surface of the first seal ring or the front surface of the compression member is configured to impart an axial and a radial sealing force on said sealing member to place the sealing member into sealing engagement with the first seal ring and the inner surface of the gland assembly.
|
