Dual non-contacting mechanical face seal having concentric seal faces

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. The first seal face further has a first portion and a second portion and the seal faces of the first and second seal rings are opposed to each other when assembled. The first seal ring or the second seal ring is adapted to rotate with the rotatable shaft, and the other seal ring is restrained from rotating. The seal faces are configured to produce 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.