Sharing on the applications of solenoid valves

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According to the insights shared by Engineer Li from Yilan Hydraulics regarding the application characteristics of solenoid valves: 1. Fast response, low power consumption, and compact design. The response time of solenoid valves can be as short as a few milliseconds, and even pilot-operated solenoid valves can have their response time kept within a few dozen milliseconds. Due to its self-contained circuit, it responds more sensitively than other automatic control valves. Well-designed solenoid valves have very low power consumption, making them energy-efficient products ； It is also possible to have the valve position automatically maintained simply by triggering the action, with no power consumption at all in normal operation. Solenoid valves have a small size, which saves space and makes them lightweight and attractive in appearance. 　　2. External leaks are completely sealed, internal leaks are easy to control, ensuring safe use. Internal and external leaks are factors that pose a threat to safety. Other automatic control valves typically extend a valve stem, with electric, pneumatic, or hydraulic actuators controlling the rotation or movement of the valve core. All of this is necessary to address the problem of external leakage in the dynamic sealing of long-term operating valve stems ； Only solenoid valves utilize electromagnetic force to act on the iron core sealed within the magnetic insulation sleeve of the electric control valve; there is no moving seal, so external leaks are easily prevented. Torque control of electric valves is difficult; internal leakage can occur easily, and in some cases the head of the valve stem may even break off ； The design of solenoid valves makes it easy to control internal leakage until it is reduced to zero. Therefore, solenoid valves are particularly safe to use, especially for corrosive, toxic, or high/low temperature media. 　　3. Various models available, with wide applications. Although solenoid valves have certain inherent limitations, their advantages remain very significant; as a result, they are designed in a variety of forms to meet different needs, making them extremely versatile in application. Advances in solenoid valve technology also focus on how to overcome inherent shortcomings and how to make better use of their natural advantages. 4. The system is simple, easy to connect to a computer, and inexpensive. Solenoid valves have a simple structure and low cost; they are easier to install and maintain compared to other types of actuators such as control valves. More significantly, the self-control system formed is much simpler and costs much less. Since the solenoid valve is controlled by switch signals, it is very convenient to connect it to an industrial computer. In today’s era of widespread computer use and significantly reduced prices, the advantages of solenoid valves become even more apparent. 　　 　　5. The adjustment accuracy is limited, and the applicable media are limited. Solenoid valves usually have only two states: on and off. The valve core can only be in two extreme positions and cannot be adjusted continuously; (there are many new ideas aimed at overcoming this limitation, but they are still in the experimental stage), so the precision of adjustment remains somewhat limited. 　　Solenoid valves have high requirements regarding the cleanliness of the medium; media containing particles are not suitable, and any impurities must be filtered out first. Furthermore, viscous media are not suitable, and the viscosity range of media suitable for specific products is relatively narrow. 　　Hydraulic Engineer Li’s views on key considerations for product selection: 1. The main control parameters for selecting solenoid valves include bore diameter, design nominal pressure, allowable temperature range of the medium, and interface dimensions. 　　2. Solenoid valves use electromagnets to open and close the valve; they are typically used for two-position control in applications with a diameter of 40 mm or less, and are especially often used to connect, disconnect, or switch gas or liquid circuits. 　　3. The sealing performance of a valve is one of the main indicators for assessing the quality of the valve. The sealing performance of a valve mainly includes two aspects: internal leakage and external leakage. Internal leakage refers to the degree of sealing between the valve seat and the closing element against the medium. External leakage refers to leaks at the valve stem packing area, leaks at the middle flange gasket area, and leaks caused by casting defects in the valve body. External leakage is not allowed. 　　4. The main advantages of solenoid valves are their small size, reliable operation, ease of maintenance, and low cost. When making a selection, it is necessary to choose between normally open and normally closed types based on the process requirements. 　 Hydraulic engineer Li believes that the key points for construction and installation are as follows: 1. The installation location and height of the valves must meet the design requirements regarding orientation, and the connections should be firm and secure. 　　2. Before installation, the valve must undergo a visual inspection; its nameplate shall comply with the provisions of the current standard GB12220 \"General Symbols for Valves\". Mr. Li from the hydraulic department, please share more other hydraulic knowledge in the future. Thank you.