As an actuator of automation instruments, the use of solenoid valves has increased dramatically in recent years. This article analyzes the main characteristics of solenoid valves, and briefly summarizes the development trends of mature technologies in China from the perspective of application, examining the directions of simplification, intelligence, generalization, and specialization. It also briefly discusses the social factors that affect the development of solenoid valve technology. 

    (1) External leakage is blocked, internal leakage is easy to control, and it is safe to use. 

    Internal and external leakage is a factor that endangers safety. Other automatic control valves usually extend the valve stem and control the rotation or movement of the valve core by electric, pneumatic, or hydraulic actuators. This is to solve the problem of external leakage of the long-term action valve stem dynamic seal; Only the solenoid valve uses electromagnetic force to act on the iron core sealed in the magnetic sleeve, without dynamic sealing, so external leakage is easily blocked. The torque control of electric valves is not easy, and it is prone to internal leakage, even breaking the head of the valve stem; The structural type of the solenoid valve is easy to control internal leakage until it is reduced to zero. Therefore, the use of solenoid valves is particularly safe, especially for corrosive, toxic or high and low temperature media. 

    (2) The system is simple, easy to connect to a computer, and low in price. 

    The solenoid valve itself has a simple structure and low price, making it easier to install and maintain than other types of actuators such as regulating valves. More significantly, the self-control system is much simpler and the price is much lower. Because the solenoid valve is controlled by switch signals, it is very convenient to connect with the industrial control computer. In today's era of widespread computer use and significant price reductions, the advantages of solenoid valves are even more pronounced. 

    (3) Fast action, small power, and lightweight appearance. 

    The response time of solenoid valve can be as short as several milliseconds, and even the pilot solenoid valve can be controlled within tens of milliseconds. Due to its self-contained circuit, it is more responsive than other automatic control valves. The solenoid valve coil with proper design has low power consumption and is an energy-saving product; It can also be triggered to automatically maintain the valve position without consuming any power. The solenoid valve has a small external dimension, which saves space, is lightweight and beautiful.