Automatic valve is a kind of valve that can automatically adjust the flow, pressure, temperature and other parameters according to the change of system parameters, which is widely used in petroleum, chemical industry, metallurgy, construction and other industries. This paper will analyze the working principle and control mode of the automatic valve from two aspects.
First, the working principle
The working principle of automatic valve is mainly through the sensor to detect the change of system parameters, the detected signal is transmitted to the actuator, the actuator adjusts the opening of the valve according to the signal, so as to achieve the automatic adjustment of flow, pressure, temperature and other parameters.
1 Sensor: The sensor is a device that converts various physical quantities in the system (such as temperature, pressure, flow, etc.) into electrical signals. Common sensors are thermocouples, thermal resistors, pressure sensors, flow sensors and so on.
2. Actuator: The actuator is a device that converts electrical signals into mechanical motion and is used to adjust the opening of the valve. Common actuators are electric actuators, pneumatic actuators, hydraulic actuators and so on.
3. Valve: The valve is a device that controls the flow, pressure, temperature and other parameters of the fluid medium. Common valves are globe valves, regulating valves, safety valves, pressure reducing valves and so on.
2. Control mode
The control methods of automatic valves are mainly as follows:
1. Opening control: By changing the opening of the valve, adjust the flow, pressure, temperature and other parameters of the fluid medium. Common opening control methods include manual opening control, electric opening control, pneumatic opening control and so on.
2. Bit control: the opening of the valve is controlled in a fixed position to control the flow, pressure, temperature and other parameters of the fluid medium. Common bit control methods include manual bit control, electric bit control, pneumatic bit control and so on.
3. Adjustment control: By adjusting the opening of the valve, the flow, pressure, temperature and other parameters of the fluid medium can be continuously adjusted. The common control methods include proportional integral-differential (PID) control, fuzzy control, neural network control and so on.
4. Intelligent control: Through the use of artificial intelligence technology, to achieve intelligent control of automatic valves. Common intelligent control methods include expert system, genetic algorithm, artificial neural network and so on.
To sum up, the working principle of the automatic valve is to detect changes in system parameters through the sensor, transmit the detected signal to the actuator, and the actuator adjusts the opening of the valve according to the signal, so as to realize the automatic adjustment of flow, pressure, temperature and other parameters. The control methods of automatic valves mainly include opening control, bit control, adjustment control and intelligent control, etc. These control methods can meet the control needs of automatic valves under different working conditions.
Post time: Sep-08-2023
