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Working principle of electric control valves and related knowledge: Electric temperature control valves: In a system, different control objectives require the use of various products in combination to achieve optimal control performance. The four principles that should be followed when selecting such products are safety, suitability, reliability, and cost-effectiveness. This valve is classified by its purpose and function as follows: a. Two-position valves b. Electric control valves c. Diversion valves d. Isolation valves. Flow characteristics of electric control valves: The relationship between the relative flow rate of the fluid passing through an electric control valve and its opening degree, under the condition that the pressure difference across the valve remains constant. The flow characteristics of electric control valves include linear, equal percentage, and parabolic types. Functions of electric control valves: Electric temperature control valves are self-acting control valves that do not require external power; they regulate temperature by adjusting the set point. As the temperature rises, the valve closes in proportion to the temperature change. A self-acting control valve consists of a control valve and a temperature controller (which includes a temperature sensor, a setpoint adjuster, a capillary, and a working piston); electric actuators are used depending on the desired temperature setting. The temperature control valve operates on the principle of liquid expansion; an increase in temperature at the sensor causes the liquid filling to heat up and expand, and under the action of the working piston the valve closes, thereby cooling the medium. Adjustment can be made step by step using the setpoint button, and the electric two-way valve can be read from the scale. Each thermostat is equipped with an over-temperature protection device. Installation of electric control valves: Electric control valves are preferably installed with the upper end of the working piston located below the horizontal pipeline. The temperature sensor can be installed in any position, provided that its entire length is submerged in the medium being controlled. Electric control valves generally include a driver that receives signals from the driver (0-10V or 4-20MA) to control the valve’s operation. As needed, they can also be integrated into an intelligent network control system to enable optimized control and remote monitoring.