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

  • A Gate valve can be a linear motion on-off or shut-off valve. The gate-valve covers a disc or wedge having two seating surfaces which come in contact using the valve seats to make a seal for stopping the flow check here. The pressure differential relating to the upstream flow direction and downstream side of wedge causes the wedge or disc to push against the downstream seat creating more effective sealing about the downstream side on the wedge. Gate valve sits dormant 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 with the gate valve is made in the form of any wedge, which is often flexible, with multiple plates or rigid.

    Let us check out each on the subcategories:
    Rigid wedge
    To ensure an increased hermiticity of gate valves, it's advocated to choose a stiff wedge. In this case, it is very important pay attention towards the accuracy of wedge processing, that allows to coordinate the seat angle while using wedge angle without obstacles. In addition to that, rigid wedge application might result in dangerous events like gate jamming, or there might be problems while using opening of gate valves regarding temperature fluctuations, corrosion build-up or sealing damages.

    Wedge with 2 plates
    The wedge is made up of several plates that are securely sure to each other and are also situated in an angle. Thanks to self-adjustment, the problem in the gate hermiticity inside the closed position is usually avoided.

    Flexible wedge
    Connected with the 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 the fact there is no need of any complex adjustment from the valve body.

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

    When the rising-stem gate valve is closed, the sealing surface are only able to rely for the medium pressure to seal, that may be, only rely around the medium pressure to press the sealing surface with the disc towards the valve seat for the other side to be sure the sealing in the sealing surface, that's self-sealing. Most gate valves adopt forced sealing valve, that is certainly, if the valve is closed, the disc have to be forced on the valve seat by external force so that the tightness with the sealing surface.