There are several ways to classify valves as follows

Types of valves and their respective characteristics/advantages and disadvantages/selection

There are many ways to classify valves based on their different functions. Here are the following:.

1. Classify by function and purpose

(1) Block valve: Block valve, also known as closed-circuit valve, is used to connect or block the medium in the pipeline. Block valves include gate valves, globe valves, plug valves, ball valves, butterfly valves, and diaphragms.

(2) Check valve: Check valve, also known as one-way valve or check valve, is used to prevent the backflow of medium in the pipeline. The bottom valve of the water pump for suction closure also belongs to the category of check valves.

(3) Safety valve: The function of safety valves is to prevent the medium pressure in pipelines or devices from exceeding the specified value, thereby achieving the purpose of safety protection.

(4) Regulating valves: Regulating valves include regulating valves, throttle valves, and pressure reducing valves, which are used to regulate the pressure, flow rate, and other parameters of the medium.

(5) Diverter valve: Diverter valves include various distribution valves and drain valves, which are used to distribute, separate, or mix media in pipelines.

2. Classified by nominal pressure

(1) Vacuum valve: refers to a valve with a working pressure lower than the standard atmospheric pressure.

(2) Low pressure valve: refers to a valve with a nominal pressure PN ¡Ü 1.6Mpa.

(3) Medium pressure valve: refers to valves with nominal pressure PN of 2.5, 4.0, and 6.4 Mpa.

(4) High pressure valve: refers to a valve with a nominal pressure PN of 10-80Mpa. This article is from Dreamweaver

(5) Ultra high pressure valve: refers to a valve with a nominal pressure PN ¡Ý 100Mpa.

3. Classified by working temperature

(1) Ultra low temperature valve: used for valves with medium working temperature t<-100 ¡æ.

(2) Low temperature valve: a valve used for medium working temperature -100 ¡æ¡Ü t ¡Ü -40 ¡æ.

(3) Room temperature valve: used for valves with medium working temperature -40 ¡æ ¡Ü t ¡Ü 120 ¡æ.

(4) Medium temperature valve: used for medium working temperature of 120 ¡æ

(5) High temperature valve: used for valves with medium working temperature t>450 ¡æ.

4. Classify by driving mode

(1) Automatic valve refers to a valve that does not require external force to drive, but relies on the energy of the medium itself to make the valve operate. Such as safety valves, pressure reducing valves

Drain valve, check valve, electric control valve, etc.

(2) Power driven valve: Power driven valves can be driven by various power sources.

Electric valve: a valve driven by electricity.

Pneumatic valve: a valve driven by compressed air.

Hydraulic valve: a valve driven by the pressure of oil or other liquids.

In addition, there are combinations of the above driving methods, such as pneumatic electric valves.

(3) Manual valve: The manual valve is operated manually by hand using a handwheel, handle, lever, and sprocket. When the opening and closing torque of the valve is large,

This wheel or worm gear reducer can be installed between the handwheel and the valve stem. When necessary, universal joints and transmission shafts can also be used for remote operation.

5. Classified by nominal diameter: (1) Small diameter valves: valves with nominal diameter DN ¡Ü 40mm.  

(2) Medium diameter valve: a valve with a nominal diameter DN of 50-300mm.

(3) Large diameter valve: a valve with a nominal DN of 350-1200mm.

(4) Extra large diameter valve: a valve with a nominal diameter DN ¡Ý 1400mm.

6. Classify by structural features

(1) Gate valve: The opening and closing component (valve disc) is driven by the valve stem to move up and down along the centerline of the valve seat;

(2) Plug valve: The opening and closing component (gate valve) is driven by the valve stem to move up and down along the centerline perpendicular to the valve seat;

(3) Plug valve: the opening and closing member (cone plug or ball) rotates around its own centerline;

(4) Rotary valve: the opening and closing member (valve disc) rotates around the axis outside the seat;

(5) Butterfly valve: The opening and closing member (disc) rotates around a fixed axis inside the valve seat;

(6) Slide valve: The opening and closing components slide in a direction perpendicular to the channel.

7. Classify by connection method

(1) Threaded connection valve: The valve body has internal or external threads and is connected to the pipeline thread.

(2) Flange connected valve: The valve body is equipped with a flange and connected to the pipeline flange.

(3) Welded connection valve: The valve body has a welding groove and is welded to the pipeline.

(4) Clamp connected valve: The valve body has a clamp and is connected to the pipeline clamp.

(5) Card sleeve connected valve: It is connected to the pipeline using a card sleeve.

(6) Clamp connection valve: a connection form that directly clamps the valve and two ends of the pipeline together with bolts.

8. Control valves classified by valve body material

(1) Metal material valve: Its valve body and other parts are made of metal materials. Such as cast iron valves, carbon steel valves, alloy steel valves, copper alloy valves, aluminum alloy valves, lead alloy valves, titanium alloy valves, Monel alloy valves, etc.

(2) Non metallic material valve: Its valve body and other parts are made of non-metallic materials. Such as plastic valves, ceramic valves, enamel valves, fiberglass valves, etc.

(3) Metal lined valve body: The valve body is made of metal, and all major surfaces that come into contact with the medium inside are lined, such as rubber lined valves, plastic lined valves, ceramic lined valves, etc.