In a rising-plug plug valve wherein the plug and valve body at the narrow end of the plug define a cavity, a passage is provided between the cavity and the outlet opening of the plug valve. On opening, MULTI-FUNCTIONAL WATER PUMP CONTROL VALVEthe valve plug and seat portion adjacent the narrowest portion of the plug is flushed by liquid passing therebetween and the outlet opening of the passageway. Plug valves have been particularly desirable valves for shut-off use for many years. However, as the size of the plug valve increases,Butterfly Valves oftentimes the amount of torque required to operate the valve also increases. In order to overcome this high torque requirement, a so-called rising- plug plug valve was developed. In a rising- plug plug valve, generally there is a mechanism provided which raises the frustoconical plug from its seat, maintains the plug either out of contact with the seat or in very light contact with the seat, permitting the plug to be rotated using minimal torque.Plug Valves The plug is then seated by forcing it into the frustoconical seat. Often, such rising- plug plug valves are subject to substantial abrasion, particularly in the region of the plug adjacent its narrower end which engages the frustoconical cavity within the valve body. Generally, such rising- plug plug valves tend to accumulate particulate material carried by the liquid flowing within the valve in the cavity defined by the smaller diameter end of the plug and the valve body. Oftentimes such particulate matter abrades the sealing surfaces of the plug and valve body. Occasionally, such a particulate matter will accumulate to a sufficient extent that the plug can no longer be successfully seated. It would be desirable if there were an improved rising- plug plug valve which was more tolerant of particulate solids than the present rising- plug plug valves. It would be also desirable if an improved valve could be readily prepared from existing valves. It would also be desirable if there were available an improved plastic lined rising- plug plug valve. These benefits and other advantages in accordance with the present invention are achieved in an improved rising- plug plug valve comprising a valve body, the valve body defining an inlet opening, an outlet opening and a passage therein, the passage providing full communication between the inlet opening and the outlet opening, the valve body defining a plug receiving cavity having a generally frustoconical configuration, the plug receiving cavity intersecting the passageway between the inlet and the outlet, a plug disposed within the plug receiving cavity, the plug having a general frustoconical configuration and mating with at least a portion of the walls of the plug receiving cavity, the plug defining a fluid passageway which on rotation of the plug permits selective communication between the inlet and the outlet end, the plug having an end of major diameter and an end of minor diameter, the plug and valve body at the plug end of minor diameter defining a closed cavity, a means to selectively position the plug in the sealing engagement with the walls defining the plug receiving cavity and means to rotate the plug, the improvement which comprises providing a passageway between the cavity defined by the plug and body and the outlet passageway.

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