Stamped-disc butterfly valve

Claim 1

A valve for controlling the flow of fluid between a pair of aligned pipe flanges interconnected by a plurality of circumferentially spaced bolts comprising: a valve body having an upstream end, a downstream end, and a bore extending therethrough and intersecting the upstream and downstream ends; cylindrical valve stem means having an upper end portion and a lower end portion and extending through the bore of the valve body, the upper and lower end portions being journaled, respectively, in the valve body for rotating relative to said valve body; a one-piece butterfly valve member in the bore of the valve body adjacent to the valve stem means in the form of a relatively rigid sheet material having all but the central poRtion thereof stamped in one direction into a dish-shape and having the central portion thereof stamped in the opposite direction to conform to the portion of the cylindrical surface of said valve stem means adjacent thereto, the outer periphery of said valve member being in a plane; securing means for rigidly securing the central portion of said butterfly valve member to said valve stem means whereby said butterfly valve member is enabled to rotate with said valve stem means to alternately open and close said valve; and seal means carried in the bore of said valve body for sealingly engaging said butterfly valve member when said butterfly valve member is in the position closing the valve.