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What are the advantages and disadvantages of pneumatic control valve compared to electric control valve?


Release time:

2022-11-19

Wuxi xinming automatic control valve industry limited company tell you what are the advantages and disadvantages of comparison of electric control valve pneumatic valve? Pneumatic control valve is based on compressed air as the power source, with the cylinder as the actuator, through the electric valve positioner, converter, solenoid valve, a valve accessories drive valve, to achieve the switch or proportional adjustment, industrial automation control system to receive the control signal, complete the pipeline medium adjustment: flow, pressure, temperature and other process parameters. Pneumatic control valve is characterized by simple control, fast response, high safety, no additional explosion-proof measures. Pneumatic control valve action gas open gas closed two kinds. Air open type is when the air pressure on the membrane head increases, the valve moves in the direction of increasing opening, and when the upper limit of the input pressure is reached, the valve is in a fully open state. Conversely, when the air pressure decreases, the valve moves in the closing direction, and when there is no air input, the valve is completely closed. Therefore, sometimes the air-open valve is also called a fail-closed type. The wind-off type moves in the opposite direction to the wind-on type. When the air pressure rises, the valve moves in the closing direction; when the air pressure decreases or does not decrease, the valve moves in the opening direction or completely opens until it is closed. Therefore, it is sometimes referred to as a fail-open type. Pneumatic control valve gas on or off, usually through the positive and negative effects of the actuator and the valve structure of the different assembly. The choice of gas-on-gas-off is based on the safety of process production. When the gas supply is cut off, is it safe for the regulator to be in the closed position or the open position? For example, in the combustion control of the heating furnace, a control valve is installed in the fuel pipe to control the fuel supply according to the temperature of the heating furnace or the temperature of the heated material at the outlet of the heating furnace. At this time, choose the gas open valve safety, because once the gas supply stops, the valve closed than the valve fully open more appropriate. If the air supply is interrupted and the fuel valve is fully open, dangerous overheating may occur. As a heat exchange equipment cooled by cooling water, the thermal material is cooled by water in the heat exchanger. The regulating valve is installed on the cooling water pipe. After the heat exchange material is used to control the cooling water temperature, the air source is interrupted and the regulator should be In the open position, it is safe, and the closed type (FO) regulator is appropriately selected. The gas-open type is changed to the gas-closed type or the gas-closed type is changed to the gas-open type. If the regulator is equipped with a smart valve positioner, it can be easily switched in the field. However, there are also some occasions when the valve is not expected to be in the fully open or fully closed position, it is not allowed to operate, but it is expected to remain in the original position before the failure. At this time, some other measures can be taken, such as the use of position maintaining valves or the installation of emergency special gas cylinders and other facilities to ensure safety. Precautions for the use of pneumatic control valves: 1. The valve should be stored in a dry room, and both ends of the path are blocked. Stacking is not allowed 2. Regulating valves stored for a long time should be checked regularly to remove dirt, and anti-rust oil should be applied to moving parts and processed surfaces to prevent rust. 3, the valve should be installed on the horizontal pipeline, requiring vertical installation. Stand up. 4. Forced installation according to the medium flow direction indicated by the arrow in the figure. The above is the content of our company today, if you have any advice, please call our company!

What are the advantages and disadvantages of pneumatic control valve compared to electric control valve?

 

Wuxi Xinming automatic control valve industry co., ltd tells youPneumatic control valveWhat are the advantages and disadvantages of contrast electric control valve?
Pneumatic control valveCompressed air is used as the power source, the cylinder is used as the actuator, and the electric valve positioner, converter, solenoid valve, a valve accessory, etc. are used to drive the valve to realize the switch or proportional adjustment. The industrial automation control system receives the control signal to complete the adjustment of the pipeline medium: flow, pressure, temperature and other process parameters. Pneumatic control valve is characterized by simple control, fast response, high safety, no additional explosion-proof measures.

Pneumatic control valve action gas open gas closed two kinds. Air open type is when the air pressure on the membrane head increases, the valve moves in the direction of increasing opening, and when the upper limit of the input pressure is reached, the valve is in a fully open state. Conversely, when the air pressure decreases, the valve moves in the closing direction, and when there is no air input, the valve is completely closed. Therefore, sometimes the air-open valve is also called a fail-closed type. The wind-off type moves in the opposite direction to the wind-on type. When the air pressure rises, the valve moves in the closing direction; when the air pressure decreases or does not decrease, the valve moves in the opening direction or completely opens until it is closed. Therefore, it is sometimes referred to as a fail-open type. Pneumatic control valve gas on or off, usually through the positive and negative effects of the actuator and the valve structure of the different assembly.

The choice of gas-on-gas-off is based on the safety of process production. When the gas supply is cut off, is it safe for the regulator to be in the closed position or the open position? For example, in the combustion control of the heating furnace, a control valve is installed in the fuel pipe to control the fuel supply according to the temperature of the heating furnace or the temperature of the heated material at the outlet of the heating furnace. At this time, choose the gas open valve safety, because once the gas supply stops, the valve closed than the valve fully open more appropriate. If the air supply is interrupted and the fuel valve is fully open, dangerous overheating may occur. As a heat exchange equipment cooled by cooling water, the thermal material is cooled by water in the heat exchanger. The regulating valve is installed on the cooling water pipe. After the heat exchange material is used to control the cooling water temperature, the air source is interrupted and the regulator should be In the open position, it is safe, and the closed type (FO) regulator is appropriately selected.

The gas-open type is changed to the gas-closed type or the gas-closed type is changed to the gas-open type. If the regulator is equipped with a smart valve positioner, it can be easily switched in the field.

However, there are also some occasions when the valve is not expected to be in the fully open or fully closed position, it is not allowed to operate, but it is expected to remain in the original position before the failure. At this time, some other measures can be taken, such as the use of position maintaining valves or the installation of emergency special gas cylinders and other facilities to ensure safety.

Precautions for the use of pneumatic control valves:

1. The valve should be stored in a dry room, and both ends of the path are blocked. Stacking is not allowed

2. Regulating valves stored for a long time should be checked regularly to remove dirt, and anti-rust oil should be applied to moving parts and processed surfaces to prevent rust.

3, the valve should be installed on the horizontal pipeline, requiring vertical installation. Stand up.

4. Forced installation according to the medium flow direction indicated by the arrow in the figure.

The above is the content of our company today, if you have any advice, please call our company!