Gate valve movement mode

When the gate valve is closed, the sealing surface can only rely on the medium pressure to seal, that is, only rely on the medium z41h flange wedge gate valve pressure will be the sealing surface of the gate to the other side of the valve seat to ensure sealing surface, this is self-sealing. Most gate valves are sealed by force, that is, when the valve is closed, rely on external force to force the gate to the seat, to ensure the sealing surface.
Movement mode: gate valve with the stem of the gate movement in a straight line, also known as the stem gate valve. There is usually a trapezoidal thread on the lifting rod, which changes the rotary motion into a straight line through the nut on the top of the valve and the guide groove on the body, that is, the operating torque into the operating thrust. When the valve is opened, when the height of the gate is 1:1 of the valve size, the flow passage is completely free, but this position cannot be monitored during operation. In practice, it is marked by the top of the stem, the unmovable position, as its full open position. To account for temperature changes, locking occurs, usually at the top position, and then back to 1/2-1 turn, as the position of the fully open valve. Therefore, the full open position of the valve is determined by the position of the gate (stroke >). Some gate valve stem nut in the gate, the handwheel turns to drive the stem to turn, and the gate to lift, this valve is called rotary stem gate valve or dark stem gate valve.