Composite plastic sealing ring - has facing of inert material on seating and contact surfaces

摘要

The screw connected pipe flanges enclose a resilient sealing ring which also pivots and seals a rotary valve plate. The ring's seating and fluid contacting surfaces are inertly faced. With hot duty the flexible base recovers for complete valve closure. The surfacing resists chemical action. The dovetail recessed pipe flanges (1) abut on the valve spindle (8, 9) centre line, containing the basic sealing ring (4) which is holed for the spindle. A compatible facing (6) enwraps the ring at the flange seatings, spindle seatings (12) and exposed surface (5). The facing's re-entrant collars (12) are ridged for additional spindle sealing.