Flange valve having improved sealing characteristics and wear indicator

Claim 1

A flange valve comprising: an integral metal valve body with a longitudinal central passage therethrough and having outwardly directed annular housing flanges at the ends thereof for connection to conduits, an ellipsoid valve member pivotally mounted within said central passage and having an aperture extending therethrough, annular resilient seats disposed within said passage and having inner annular portions with surfaces in contact with end portions of said valve member, a pair of removable annular liners disposed in opposite ends of said valve body and having end portions abutting said inner portions of said resilient seats, and liners dimensioned to be removably inserted from the exterior of said valve body into opposite ends of said central passage of said valve body to form a close fit such that said liners may be removed for repair or replacement from said central passage by sliding said liners in an outward direction along said central passage without the requirement of disassembly of said valve body; said liners constructed from non-corrosive material to prefent corrosion of said valve body, said liners having annular liner flanges which abut against the outer ends of said valve body and for being held in place by the conduits attached to said housing flanges, annular spacer rings having first and second ends and being disposed between said valve body and said annular liners with said first ends bearing against said resilient seats, said liner flanges engaging said second ends of said spacer rings to press said first ends of said spacer rings against said resilient seats to urge said resilient seats against said valve member, and means for rotating said valve member to open and closed positions.