Valves are classified according to their functions and uses:

(1) Cut-off type: such as gate valve, Globe/Stop/shutoff valve, plug valve, ball valve, butterfly valve, needle valve, diaphragm valve, etc. Shut-off valves are also called closed-circuit valves/stop valves. Mainly used to cut off and connect fluid media.
(2) Check valve: Check valve, also known as check valve or check valve. Check valve is an automatic valve. Mainly used to prevent backflow of fluid media.
(3) Safety category: such as safety valve, explosion-proof valve, emergency valve, etc. The function of the safety valve is to prevent the medium pressure in the pipeline or device from exceeding the specified value, so as to achieve the purpose of safety protection. Mainly used for safety protection to prevent damage to boilers, pressure vessels or pipelines.
(4) Regulators: such as regulating valves, throttle valves, pressure reducing valves and thermostatic valves. Mainly used to adjust the flow, pressure, temperature, etc. of fluid media.
(5) Diversion type: such as distribution valve, three-way valve, multi-way valve, trap valve, spool valve. Mainly used for distribution, separation and mixing of fluid media.
(6) Special purpose categories: such as pigging valve, vent valve, drain valve, exhaust valve, filter, etc.
Gate valve is one of the most common opening and closing valves, which use gates (that is, opening and closing parts, in the gate opening and closing parts are called gates or gates, and the gate seat is called the gate seat) to switch on (fully open) or Cut off (fully closed) the medium in the pipeline. It is not allowed to be used for throttling. Avoid opening the gate slightly during use. The erosion of the high-speed flowing medium will accelerate the damage of the sealing surface. The Shuangde gate acts as a lifting movement on the side perpendicular to the center line of the gate seat channel, and cuts off the medium in the pipeline like a gate, so it is called a gate valve.

Specification of Air Valve

High water pipelines or long water pipelines often produce water column separation due to pressure drop during power outages or pump shutdowns. An air valve can be installed to protect the pipeline. Air valve is sometimes called exhaust valve or intake valve.

Install air valves at the high point of the pressure water tank of the pumping station and on the water delivery pipelines to discharge the air in the water delivery pipeline to avoid pressure fluctuations when the water delivery pipeline is initially filled with water, and the pipeline is filled after regular maintenance. When the water hammer produces negative pressure in the water pipeline, the air valve is opened to allow the air outside the pipeline to enter the pipeline to avoid large negative pressure in the pipeline, which plays a protective role; when the pipeline system is operating, when the pipeline is due to pressure or temperature When the change causes the air dissolved in the water to be released, the air valve will discharge it in time to prevent the formation of air bags in the pipeline and affect the operation of the pipeline system.