Sleeve lined plug valves

Claim 1

IN A SLEEVE LINED PLUG VALVE INCLUDING A METALLIC BODY HAVING A BORE EXTENDING TRANSVERSELY THEREOF AND PORTS THERETHROUGH OPENING INTO SAID BORE IN ANGULARLY SPACED RELATION, THE COMBINATION OF A TAPERED METALLIC VALVE PLUG RECEIVED IN SAID BORE AND HAVING A PORT THERETHROUGH FOR ALIGNMENT WITH SAID BODY PORTS, MEANS TO EFFECT MOVEMENT OF SAID PLUG FROM MONE POSITION TO ANOTHER RELATIVE TO SAID BODY TO PLACE SAID PLUG PORT IN AND OUT OF FLUID COMMUNICATION WITH SAID BODY PORT, SAID PLUG BEING OF SUFFICIENTLY SMALLER RADIAL DIMENSIONS THAN SAID BORE TO ESTABLISH AN ANNULAR CLEARANCE BETWEEN THE OPPOSED SURFACES THEREOF, SLEEVE LINER MEANS RECEIVED IN SAID CLEARANCE AND HAVING PORTS THEREIN MATCHING SAID BODY PORTS, MEANS MAINTAINING SAID PLUG IN SEALING ENGAGEMENT WITH SAID LINER MEANS DURING MOVEMENT FROM ONE POSITION TO ANOTHER, SAID LINER MEANS BEING FORMED OF A FLUOROCARBON MATERIAL HAVING A COEFFICIENT OF THERMAL EXPANSION SUBSTANTIALLY GREATER THAN THAT OF SAID PLUG AND BODY, SAID BORE HAVING A CONTINUOUS ANNULAR GROOVE SURROUNDING EACH OF SAID BODY PORTS, SAID BODY INCLUDING AN ANNULAR SHOULDER FORMING THE INNER WALL OF EACH SAID ANNULAR GROOVE AND ALSO THE INNER END OF THE ASSOCIATED SAID BODY PORT, SAID LINER MEANS INCLUDING MEANS DEFINING A CONTINUOUS CIRCUMFERENTIAL SEAL EXTENDING COMPLETELY AROUND THE OUTER PERIPHERY OF SAID PLUG, SAID LINER MEANS INCLUDING INTEGRAL PORTIONS RECEIVED IN SAID GROOVES AND PROVIDING A CONTINUOUS RING PORTION OF SAID LINER MATERIAL SURROUNDING SAID BODY PORTS, SAID SHOULDERS INTERFITTING WITH SAID LINER PORTS TO CONFINE SAID SURROUNDING RINGS OF LINER MATERIAL AGAINST MOVEMENT WITH RESPECT TO SAID BORE AND FLOW INTO SAID BODY PORTS, AND SAID RING PORTIONS OF SAID LINER MEANS BEING OF SUFFICIENT THICKNESS TO MAINTAIN SAID PLUG OUT OF CONTACT WITH SAID SHOULDERS.