Plug valve

A high temperature high-pressure water-cooled lubricated gas-tight steel plug valve adapted for controlling hot abrasive particulate materials passing through said valve, comprising a water-cooled hollow double-walled housing having an inlet passage and an outlet passage generally opposite to said inlet passage;

• the double walls of said housing form at least one hollow interior having cooling fluid inlet and outlet pipes;
• a generally cylindrical hollow plug having a bore passage therethrough, having at least one axial stem, and being rotatably mounted with close tolerances within said housing from an open position, where said bore passage registers with said inlet and said outlet passages, to a gas-tight closed position out of registry therewith;
• said bore passage being formed of a transverse pipe within said plug;
• a baffle positioned within said plug and along said pipe so as to block flow of cooling fluid past said baffle around said pipe within said hollow plug, within one axial stem an inlet axial flow passage positioned to feed cooling fluid to one side of said baffle and an outlet axial flow passage positioned to withdraw feed cooling fluid from the other side of said baffle;
• at least one relatively thin-walled replaceable iron wear liner of a wholly cylindrical hollow shape, located surrounding said plug member and inside said housing;
• any such wear liner having at least two openings corresponding to and shaped to register with said inlet and said outlet passages of the housing;
• there being no more than two such wear liners;
• said at least one replaceable wear liner being fixed gas-tight to one of said plug and said housing and being in gas-tight engagement with the other of said plug and said housing together with any single wear liner which may be fixed on such other, said valve being so structured and any such liner being so positioned in such a manner that any such liner is capable of being cooled by cooling fluid circulating in said housing and in said plug sufficiently to prevent differential expansion between the iron of any wear liner therein and the steel of the remainder of the valve.