Electric control valve is an important executive unit in industrial automation system. With the increasing degree of automation in the industrial field, it is being used more and more in production. Compared with the traditional pneumatic control valve, it has outstanding advantages:
· energy-saving (electricity consumed when working)
· environmental (carbon-free release)
· and easy to install (complicated pipelines and pump workstations not required)
Based on the power used by its actuator, electric control valves may have different functions and characteristics. Generally speaking, it can be divided into three types: linear characteristic, equal percentage characteristic and parabolic characteristic.
1. The main parameters of the electric control valve are: nominal diameter, design nominal pressure, allowed medium temperature range, CV, etc.
2. For situations where the flow needs to be strictly in proportion to the opening rate, special regulating valves should be used.Ball valves and butterfly valves are better used for not so strict situations. Valves need to be carefully selected to match the required flow characteristic.
3. “Tightness” is a key indicator to the quality of valves. It is determined by two aspects: internally and externally. Inner sealing refers to how effective the seat and the closing part hold the medium. External sealing refers to how tight the packing gland, gasket and the valve body. No leakage is allowed.