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 this reason it is one of the basic industrial valve types.
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 light 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. Each valve is 100% tight when leaving the factory; the tightness is checked by a water or gas pressure test.
Mostly, similar gate valves can be used with gas and liquid. However, in the case of gas, closer attention must be paid to the stem seal emission level when compared to liquid applications. A low emission valve is both user and environment-friendly. In addition, emissions through the stem seal are in essence medium losses. In addition to low-emission (ISO 15848, API 622, API 624) models with stem seals, our product range includes models with bellows seals for process conditions where it is necessary to ensure no medium is released into ambient air via the stem seal.
Most common materials are carbon steel and acid-proof steel, but other alternatives such as affordable spheroidal graphite cast iron, cold-resistant LF2 steel and more exotic materials are also available on order.
In addition to manual operation, all gate valves can be equipped with electric actuators.
Our product range includes gate valves for gas and liquid fuel transfer and distribution piping. The range includes size classes DN 15-1000 and pressure ratings PN 4-320; ANSI classifications up to 2500# are also available. Connection options include flanges and welding ends.