Classification of valves

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There are many types of valves, and there are multiple classification methods.

There are many types of valves, and there are multiple classification methods.
一、Classified by purpose and function
1. Block valves are mainly used to cut off or connect medium flow. Including gate valves, globe valves, diaphragm valves, plug valves, ball valves, butterfly valves, etc.
2. Regulating valves are mainly used to regulate the flow rate, pressure, etc. of media. Including regulating valves, throttle valves, pressure reducing valves, etc.
3. Check valves are used to prevent the backflow of media. Including check valves of various structures.
4. Diverter valves are used for distributing, separating, or mixing media. Including various structures of distribution valves and drain valves.
5. Safety valves are used for overpressure safety protection. Like a safety valve.
二.、The Classified by main parameters
1、 Classified by pressure
(1) Valves with working pressure lower than standard atmospheric pressure.
⑵ Valves with a nominal pressure PN<1.6MPa for low-pressure valves.
⑶ A valve with a nominal pressure of PN2.5-6.4Mpa for medium pressure valves.
⑷ High pressure valves with a nominal pressure of PN10.0-80.0Mpa.
⑸ Valves with a nominal pressure PN greater than 100Mpa for ultra-high pressure valves.
2 、Classified by working temperature of the medium
⑴ Valves with high temperature t>450 ℃.
⑵ Medium temperature valves with temperatures between 120 ℃ and 450 ℃.
⑶ Normal temperature valves - valves with a temperature range of 40 ℃<t<120 ℃.
⑷ Low temperature valve -100 ℃<t<-40 ℃.
⑸ Valves with ultra-low temperature t<-100 ℃.
3、 Classification by valve body material
⑴ Non metallic material valves such as ceramic valves, fiberglass valves, and plastic valves.
⑵ Metal material valves such as copper alloy valves, Monel alloy valves, cast iron valves, carbon steel valves, and alloy steel valves
⑶ Metal valve body lined valves such as lead lined valves, plastic lined valves, and enamel lined valves.
三、 Common Categories
This classification method is based on both principles, functions, and structures, and is currently the most commonly used classification method both domestically and internationally. Generally divided into: gate valve, globe valve, plug valve, ball valve, butterfly valve, diaphragm valve, check valve, throttle valve, safety valve, pressure reducing valve, drain valve, and regulating valve.
四、According to the structural characteristics, it can be classified based on the direction of movement of the closure relative to the valve seat：
1. Truncated gate shape：

The closing component moves along the center of the valve seat，As shown in the figure.
2. Gate shaped：

The closure moves along the center of the vertical valve seat，As shown in the figure.
3. Plug and ball：

The closing component is a plunger or ball,Rotate around its own centerline,As shown in the figure.
4. Spiral opening shape

The closure rotates around the axis outside the valve seat,As shown in the figure.
5. dish：

The disk of the closure component,Rotate around the axis inside the valve seatAs shown in the figure.
6. Slide valve shape：

The closure slides in a direction perpendicular to the channel,As shown in the figure.
五、According to the driving method, it can be divided into:
1. Manual: With the help of handwheels, handles, levers, or sprockets, it is driven manually and equipped with worm gears, gears, and other reduction devices when transmitting large torque.

2、Electric: driven by an electric motor or other electrical device.

3、Hydraulic: driven by (water, oil).

4、Pneumatic; Driven by compressed air.

6、According to the connection method with the pipeline, it can be classified according to the connection method between the valve and the pipeline：
1. Flange connected valve: Flange connection refers to a detachable connection in which a flange, gasket, and bolt are connected to each other as a combined sealing structure. Pipeline flange refers to the flange used for piping in pipeline installations, and when used on equipment, it refers to the inlet and outlet flanges of the equipment. The flange connection is easy to use and can withstand high pressure.

Photo of flange connection

Legend of flange connection
2、Threaded connection valve: A valve with a valve body that has internal or external threads and is connected to a pipeline using threads.