| 摘要 |
Disclosed is an emergency shaft seal for remote actuation in the event the primary shaft seal fails. The emergency shaft seal includes a seal housing rotatably mounted on an element rotatable with the shaft. At least one end face seal is carried by and rotates with the element. The end face seal engages a sealing surface on a gland plate carried by the seal housing whereby the housing is frictionally engaged and normally rotates with the element and shaft. An inflatable bladder is carried by a housing fixed to structure supporting the shaft and element for rotation and encircles the seal housing. The seal housing, rotatable element, and bladder housing define an area on the side of the primary seal remote from the shaft bearing lubricants and which area normally lies in open communication with the surrounding environment through the annular space between the bladder and seal housing. When the primary seal fails and shaft bearing lubricants leak into this area, the bladder is inflated and expands radially inwardly to engage the seal housing and prevent its rotation relative to the end face seal. The bladder and seal housing form a static seal while the rotating end face seal and stationary gland plate surface form a dynamic seal whereby the area, into which the shaft bearing lubricants leak upon failure of the primary seal, is sealed from the surrounding environment. |
