Basic characteristics of wedge gate valve
The difference between wedge gate valve and flat gate valve is that the closing member of wedge gate valve is wedge rather than parallel. The purpose of using wedge valve plate is to increase the auxiliary sealing load, so that the metal sealed wedge gate valve can not only ensure high medium pressure sealing, but also make low medium pressure sealing. In this way, the potential sealing degree of metal sealed wedge gate valve is higher than that of ordinary metal seal flat gate valve. However, the sealing load at the inlet end of metal seal wedge gate valve caused by wedging is often insufficient to achieve the sealing at the inlet end, so the wedge gate valve is forced to seal on one side.
The disadvantage is that the wedge gate valve can't set the diversion hole like the flat gate valve with diversion hole, and the thermal expansion of the valve stem will overload the sealing surface. Moreover, the wedge gate valve is more likely to contain solid particles in the flow medium than the plate gate valve.
The common types of wedge gate valve are: rising stem wedge single gate valve, Non rising stem wedge single gate valve, rising stem wedge double gate valve, Non rising stem wedge double gate valve, purging gate valve.