[Tianjin One Standard Valve] How are valves classified?
Published: April 23, 2016 Author: 【191566.com】
There are many types of valves and their applications are also very wide. So how are they classified?
First, according to the structural characteristics, it can be divided according to the moving direction of the closing member relative to the valve seat:
1. Gate-shaped: The closing piece moves along the center of the valve seat.
2. Gate shape: The closing piece moves along the center of the vertical valve seat.
3. Plug and ball: The closing member is a plunger or ball, which rotates around its own centerline.
4. Swing shape; the closing part rotates around the shaft outside the valve seat.
5. Dish-shaped: The disc of the closing part rotates around the axis in the valve seat.
6. Spool type: The closing piece slides in a direction perpendicular to the channel.
According to the purpose, it can be divided according to the different uses of the valve:
1. Opening and closing: used to connect or cut off the pipeline medium, such as globe valve, gate valve, ball valve, butterfly valve, etc.
2. Non-return use: used to prevent the medium from flowing backward, such as a check valve. 3. Regulating: Used to adjust the pressure and flow of the medium, such as regulating valves and pressure reducing valves.
4. Distribution: used to change the flow direction of the medium, such as three-way cocks, distribution valves, slide valves, etc.
5. Safety valve: When the pressure of the medium exceeds the specified value, it is used to discharge excess medium to ensure the safety of piping systems and equipment, such as safety valves and accident valves.
6. Other special uses: such as traps, vent valves, blowdown valves, etc.
Third, according to the driving method, it can be divided according to different driving methods:
1. Manual: With the help of hand wheel, handle, lever or sprocket, etc., it is driven by human power. When transmitting large torque, it is equipped with reduction gears such as worm gear and gear.
2. Electric: driven by a motor or other electrical device.
3. Hydraulic: driven by (water, oil).
4. Pneumatic; driven by compressed air.
4.Pressing pressure can be divided according to the nominal pressure of the valve:
1. Vacuum valve: A valve with an absolute pressure of <0.1MPa, that is, 760mm Hg, usually expressed in mmHg or mmHg.
2. Low pressure valve: Valves with nominal pressure PN≤1.6MPa (including steel valves with PN≤1.6MPa)
3. Medium pressure valve: Valve with nominal pressure PN2.5-6.4MPa.
4. High pressure valve: a valve with a nominal pressure of PN10.0-80.0MPa.
5. Ultra-high pressure valve: a valve with a nominal pressure PN≥100.0MPa.
V. According to the temperature of the medium, it can be divided according to the temperature of the medium when the valve is working:
1. Ordinary valve: suitable for valves with a medium temperature of -40 425 ¡ã C.
2. High temperature valve: suitable for valves with medium temperature 425 600 ℃.
3. Heat-resistant valve: suitable for valves with medium temperature above 600 ℃.
4. Low temperature valve: suitable for valves with medium temperature -40 -150 ℃.
5. Ultra-low temperature valve: suitable for valves with medium temperature below -150 ℃.
6.According to the nominal diameter, it can be divided according to the nominal diameter of the valve:
1. Small-caliber valves: Valves with a nominal diameter of DN <40mm.
2. Medium-caliber valves: Valves with a nominal diameter of DN50-300mm.
3. Large-caliber valves: Valves with a nominal diameter of DN350-1200mm.
4. Extra large diameter valves: Valves with a nominal diameter of DN 1400mm or more.
Seven, according to the connection with the pipeline, can be divided according to the valve and pipeline connection;
1. Flanged valve: The valve has a flange and the valve is flanged to the pipeline.
2. Threaded valve: Valve with internal or external thread and a threaded connection to the valve.
3. Welding connection valve: The valve body has a welding port, and the valve is connected to the pipeline by welding.
4. Clamp connection valve: The valve has a clamp on the valve body, and the valve is connected to the pipeline by a clamp.
5. Card sleeve connection valve: a valve connected to the pipeline by a clip sleeve.