The shut-off part in the gate valve was created in the form of

  • A Gate valve is usually a linear motion on-off or shut-off valve. The gate-valve consists of a disc or wedge having two seating surfaces that will in contact with all the valve seats to create a seal for stopping the flow check here. The pressure differential between upstream flow direction and downstream side of wedge causes the wedge or disc to just make against the downstream seat creating more effective sealing for the downstream side on the wedge. Gate valve just sits there to regulate flow as erosion of disc and seat could cause leakage. A gate valve in partially open or closed position is usually susceptible to vibration.

    The shut-off part in the gate valve was made in the form of an wedge, that may be flexible, with multiple plates or rigid.

    Let us look at each with the subcategories:
    Rigid wedge
    To ensure a top hermiticity of gate valves, experts recommend to choose a stiff wedge. In this case, you should pay attention for the accuracy of wedge processing, allowing to coordinate the seat angle while using wedge angle without obstacles. In addition to that, rigid wedge application could potentially cause dangerous events like gate jamming, or there are problems while using opening of gate valves in the event of temperature fluctuations, corrosion build-up or sealing damages.

    Wedge with 2 plates
    The wedge contains several plates that are securely likely to each other and they are situated with an angle. Thanks to self-adjustment, the problem from the gate hermiticity inside closed position might be avoided.

    Flexible wedge
    Connected through an elastic part, the plates can clamp down and improve sealing tightness in closed position. The advantage of gate valves which has a flexible wedge for mounting from the pipeline is always that there is no need of your complex adjustment on the valve body.

    The sorts of rising-stem gate valve could be divided into wedge disc gate valve and parallel disc gate valve good sealing surface configuration. Wedge disc gate valve could be divided into: single disc type, double disc type and elastic disc type; parallel disc Type gate valve might be divided into single disc type and double disc type. According towards the thread position in the valve stem, it could be divided into rising-stem gate valve and non rising-stem gate valve.

    When the rising-stem gate valve is closed, the sealing surface could only rely within the medium pressure to seal, that is certainly, only rely around the medium pressure to press the sealing surface in the disc towards the valve seat within the other side to guarantee the sealing from the sealing surface, that is self-sealing. Most gate valves adopt forced sealing valve, which is, in the event the valve is closed, the disc need to be forced towards the valve seat by external force to guarantee the tightness from the sealing surface.