Ball valve with a reinforced and deformable valve seat

Claim 1

A ROTARY PLUG VALVE, COMPRISING A BODY HAVING A FLOWWAY THERETHROUGH AND A PLUG MEMBER ROTATABLE THEREIN BETWEEN FLOWWAY OPENING AND CLOSING POSITIONS, MEANS INCLUDING A FLANGE PROVIDING AN ANNULAR RECESS IN THE BODY IN SURROUNDING RELATION TO THE FLOWWAY, SAID RECESS HAVING INNER AND OUTER SPACED-APART WALLS ONE OF WHICH IS ON THE FLANGE, AND A PLASTIC SEAT RING WITHIN THE RECESS FOR ENGAGEMENT WITH THE VALVE MEMBER, SAID RING HAVING RADIALLY SPACED-APART LAYERS OF REINFORCING MATERIAL MOLDED WITHIN THE PLASTIC THEREOF, AND SAID FLANGE BEING CRIMPED INTO THE RING THROUGHOUT AT LEAST A PORTION OF ITS CIRCUMFERENCE TO DEFORM IT RADIALLY AND THEREBY SECURE IT IN PLACE AND HAVING THE RECESS WALL THEREOF LYING AGAINST THE CRIMPED AREA OF THE RING CURVED CONVEXLY WITH RESPECT TO THE RING SO AS TO TURN THE ENDS OF THE LAYERS OF REINFORCING MATERIAL TOWARD THE PLUG AND DISTRIBUTE STRESS IN THE CRIMPED AREA OF THE RING.