What Are The Three Types Of Gate Valves?

There are many types of gate valves according to different classification standards. Common classification methods include structural characteristics, sealing methods, driving methods, etc. If classified by structural characteristics, gate valves are mainly divided into the following three types:

1. Wedge gate valve

Features: The gate and the valve seat sealing surface are wedge-shaped, and the sealing is achieved by the wedge structure. The wedge angle is usually 2°52′, 5°, or 8°, and the specific angle is selected according to the medium temperature and pressure.

Classification:

Single gate wedge gate valve: simple structure, but high requirements for the sealing surface angle accuracy; easy to wedge when the temperature changes.

Double gate wedge gate valve: composed of two gates, low requirements for the sealing surface angle accuracy, not easy to wedge when the temperature changes, and gaskets can be added to compensate for the wear of the sealing surface.

Elastic gate wedge gate valve: There are elastic grooves around the gate, which can produce slight deformation to compensate for the angle deviation of the sealing surface. It is suitable for various temperatures and pressures.

2. Parallel gate valve

Features: The gate is parallel to the valve seat sealing surface, and the sealing surfaces on both sides of the gate are in contact with the valve seat at the same time, which is suitable for medium and low pressure and large diameter occasions.

Classification:

Single-gate parallel gate valve: simple structure, but the sealing surface is easy to wear.

Double-gate parallel gate valve: the gate is kept in contact with the valve seat by springs or thrust wedges, and the sealing performance is better.

3. Knife-type gate valve

Features: The gate is blade-shaped, suitable for pipelines containing particles, fibers, or viscous media, which can cut off the media and prevent blockage.

Application: Commonly used in sewage treatment, papermaking, the chemical industry, and other industries.

Other classification methods are supplemented.

According to the valve stem position: rising stem gate valve (the valve stem rises and falls, and the opening can be observed) and concealed stem gate valve (the valve stem rotates and does not rise and fall).

According to the sealing surface material, there are soft sealing gate valves (such as rubber and polytetrafluoroethylene) and hard sealing gate valves (such as metal and ceramic).

According to the driving method: manual gate valve, electric gate valve, pneumatic gate valve, etc.

The type of gate valve should be selected based on the medium characteristics, pressure, temperature, diameter, and other factors. Wedge gate valves are suitable for high-pressure and high-temperature occasions, parallel gate valves are suitable for medium- and low-pressure large-diameter pipelines, and knife gate valves are suitable for working conditions containing particles or viscous media.