A rotary plug valve having a body including a wall defining a plug receiving chamber, a plug member including fluid passage therethrough and having a peripheral side wall portion having a selected diameter, GLOBE VALVEsaid side wall portion having at least a resilient material to a selected depth, said wall of said body having openings therein disposed so that when said plug member is rotatably located in said chamber, said fluid passage will be alignable in flow communication with at least some of said openings, Plug Valvessaid wall further including raised metallic surface formed thereon extending from said wall into said chamber to a selected distance and located in a selected pattern relative to said openings so that, Resilient Seated Gate Valveswhen said plug member is rotatably disposed in said plug receiving chamber, said metallic surface means will locally deform said resilient material and thereby sealingly engage sections of said resilient material of said plug member to substantially prevent leakage of fluid therebetween. In view of the fact that the sealing elements of these valves and the valve elements themselves are subjected to wide ranges of fluid pressures as well as grit and dust that are frequently carried in the fluids being handled, certain limitations on the valve sealing elements have been encountered in designing these types of valve members. In one type of arrangement, it has been the practice to form the plug member of the valve with grooves which extend peripherally about the plug member fluid passage opening. Sealing elements such as O-rings would then be placed in the grooves. Such arrangements often required, for many applications, the provision of special lubrication to maintain the integrity of the seal over the life of the valve body. In addition, the machining of the groove has often been a significant manufacturing difficulty as well as a limitation on the design of the valve plug itself in terms of the shape and orientation of the fluid passageway therethrough. In particular, the machining of an oval groove in the plug body about the periphery of an opening therethrough has been both time consuming and expensive in terms of the labor and equipment required to carefully machine such a groove. In other arrangements, where a machined groove has been employed to house a sealing element, certain applications have required a specially designed seal to resist degradation of the sealing effect as a result of exposure to grit and dirt in certain environments. This has materially increased the manufacturing costs of such valves. In another technique, it has been the practice to cover the valve plug member with a resilient cover such as of molded rubber or other suitable elastomer such as that sold under the trademark Neoprene. Alternately, the valve body chamber in which the plug was to be inserted, in some arrangements, has been coated with the resilient material. In either case, the sealing effect depended largely on the exact manufacturing tolerances as between the outer diameter of the plug member and the facing wall of the plug receiving chamber of the valve body. The maintenance of such close tolerances as were required to assure proper operation of the valve over its useful life materially increases the manufacturing costs on the one hand, and, on the other, with such valve structures, it was difficult to compensate for differential expansion as between the valve elements themselves and the resilient material covering that was employed. Further, operation of the valve could often be materially impeded by uneven wear on the resilient cover particularly where the fluid being handled carried any significant quantity of grit and dirt. In addition, where any pressure fluids were involved, in order to minimize the effect of cold flow of the rubber covering, a false port often had to be provided on the face of the plug member to absorb any bulge or distortion caused by a long term shut-off of the valve. In addition a false port is useful to prevent grit and dust from adhering to the seating surfaces which could result in damage to the seating surfaces upon rotation of the valve between its operating positions. A false port, in this case, is provided by forming a recess in the covering material and/or in the plug member itself to reduce seating contact and to thereby render turning of the plug member in the valve body easier.

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