Wedge gate valves
In wedge gate valves, the closing element is a wedge-like gate. Sealing surfaces are flat. Due to the wedge-like shape, tightening of the valve increases surface pressure on the sealing surfaces. The structure of a gate valve is fairly simple, for which reason it is one of the basic industrial valve types. Wedge gate valves are an excellent choice for high temperatures and pressures.
The wedge may be split, solid or flexible. A split wedge consists of two wedge parts. This allows tight closure, even if the valve is subjected to slight torsion or varying operation temperatures. Flexible wedges are provided with a groove in their edges. This groove allows slight bending of the wedge seal surfaces under great forces, which facilitates the opening of the valve. A solid wedge has no such grooves. Owing to its compact size, it fits short-structured wedge gate valves and large size classes.
Wedge gate valve seals can be solid, threaded, pressed, welded, or any combination of these. Almost any metallic material can be used as the seal surface material.
Most typical materials are carbon steel and acid-proof steel, but other material options are available as well.
In addition to manual operation, all wedge gate valves can be equipped with electric actuators.