Flange gate valve is connected to the flange of the valve, this connection is the most common. Flange valve in the pipeline when used in stable and reliable, so often used in high-pressure pipe flange valve.
When the gate valve is closed, the sealing surface can be sealed only by the medium pressure, that is, by means of the medium pressure to press the sealing surface of the gate to the other side of the valve seat to ensure that the sealing surface of the seal, which is self-sealing. Most of the gate valve is forced to seal, that is, when the valve is closed, to rely on external force forced to the gate pressure to the valve seat to ensure that the sealing surface of the seal.
When the valve is opened, when the height of the gate is equal to 1: 1 times the diameter of the valve, the fluid channel is completely open, but this position can not be monitored during operation. The actual use of the stem is the vertex as a sign, that is, the location of the open, as its full open position. In order to consider the temperature changes appear locking phenomenon, usually in the open to the vertex position, and then back 1 / 2-1 lap, as the full valve position. Therefore, the fully open position of the valve, according to the position of the gate (ie stroke) to determine.