Abstract: A valve for feeding abrasive particulate material to, and removal of particulate material from a pressurized vessel, adapted to operate at temperatures above 500.degree. C., comprises a valve structure wherein a single shutoff member of generally spherical shape performs both functions of shutoff the particulate material and the gas-tight sealing by means of a resilient inflatable circular seal element which engages the convex side of said shutoff member. Said seal element is inflated and cooled by a pressure regulated and continuously flowing stream of liquid water. The seal element is protected from being damaged at high temperatures by contacting it with the cooled shutoff member when the valve is closed and with a cooled circular extension of the shutoff member when the valve is open.

Abstract: A high temperature water-cooled gas-tight lubricated steel plug valve for handling abrasive particulates (such as iron ore or sponge iron) having a water-cooled hollow double-walled housing with opposing inlet and outlet, a hollow internally-baffled axially water-cooled cylindrical plug with a transverse flow pipe defining a bore therethrough, at least one relatively thin-walled replaceable iron wear liner of generally cylindrical shape having corresponding bore passages and being positioned around said plug member and fixedly keyed within said housing whereby wear is generally limited to the relatively-moving interfacing inner surface of the wear liner and the outer surface of the plug member. The plug being machinable to restore the proper shape and tolerances when combined with replacement of the wear liner by one of compensatingly greater thickness.