| 摘要 |
A seating element is positioned in a flow cutoff device. The seating element includes a central opening for conducting fluid flow. The flow cutoff device includes an apertured sealing member which slides across a seating portion of the seating element between open and closed positions. The seating portion includes a rim surrounding the central opening and a transverse surface surrounding the rim. The rim projects axially beyond the junction of the rim and surface. The seating element is mounted under compression so that the transverse surface flexes against the sealing member and functions to scrape away particulate matter when the sealing member is opened and closed, and to prevent twisting of the rim.
|
