Some basic facts about solenoid valves

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I. Safety: Neglecting safety can lead to disasters! 1. Corrosive media: Plastic King solenoid valves and all-stainless steel options are recommended ； For highly corrosive media, an isolated diaphragm type must be used. Example CD-F. Z3CF. In neutral media, it is also advisable to use copper alloys as the material for the valve housing in solenoid valves; otherwise, rust particles often fall off from the valve housing, especially in situations where the valve is not used frequently. Copper materials cannot be used for ammonia valves. 2. Explosive environments: Products with the appropriate explosion-proof rating must be selected; for outdoor installations or locations with high dust levels, waterproof and dust-proof models should be used. 3. The nominal pressure of the solenoid valve should exceed the highest operating pressure in the pipeline. II. Applicability: It’s pointless to use it – it’s just wasting money and causing trouble! 1. Medium properties: 1.1 Different types of solenoid valves should be used for gaseous, liquid, or mixed states; for example, ZQDF is used for air, ZQDF—Y for liquids, and ZQDF—2 (or -3) for steam – otherwise, malfunction may occur. The ZDF series of multi-functional solenoid valves can be used with both gas and liquids. It is best to specify the medium condition at the time of ordering, so that the installation user does not need to adjust it again. 1.2 Products of different specifications are required for different medium temperatures; otherwise, the coils will burn out and the seals will age, severely affecting their lifespan. 1.3 Dielectric viscosity, usually below 50 cSt. If this value is exceeded, and the passage diameter is greater than 15 mm, a ZDF series multi-functional solenoid valve must be ordered as a special order. Solenoid valves with a bore diameter of less than 15 mm for high viscosity fluids. 1.4 When the cleanliness of the medium is not high, a backflow filter valve should be installed in front of the solenoid valve; when the pressure is low, a direct-acting diaphragm solenoid valve such as CD—P can be used. 1.5 If the 1.5 medium flows in a directed manner and backflow is not allowed, ZDF—N and ZQDF—N require bidirectional flow only; special requests should be submitted in such cases. 1.6 The medium temperature should be within the range permitted by the solenoid valve. 2. Pipeline parameters 2.1 Select the valve ports and models based on the requirements regarding the flow direction of the medium and the piping connection method. For example, when switching from one pipe to two pipes, choose CA5 and Z3F for small diameters; for medium or large diameters, select ZDF—Z1/2. For example, to control the convergence of two pipelines, select ZDF—Z2/1, etc. 2.2 The nominal diameter is selected based on the flow rate and the Kv value of the valve; it can also be chosen to match the inner diameter of the pipeline. Please note that some manufacturers do not indicate the Kv value; often, the valve orifice size is smaller than the diameter of the connection pipe. Do not settle for a lower price at the risk of causing problems. 2.3 Operating pressure difference: An indirect pilot type can be used provided that the minimum operating pressure difference is above 0.04 Mpa ； Those with a minimum operating pressure difference close to or less than zero must use direct-acting or step-direct-acting types. 3. Environmental Conditions 3.1 The maximum and minimum temperatures of the environment should be within the allowable range; if they exceed these limits, a special order must be placed. 3.2 In environments with high relative humidity or exposure to water droplets and rain, waterproof solenoid valves should be used. 3.3 In environments where there is frequent vibration, jolting, and impact, special types should be selected, such as marine solenoid valves. 3.4 In corrosive or explosive environments, corrosion resistance should be given priority in selection based on safety requirements. 3.5 If the environmental space is limited, choose a multi-functional solenoid valve, as it eliminates the need for a bypass and three manual valves and facilitates online maintenance. 4. Power supply conditions 4.1 AC and DC solenoid valves are selected accordingly based on the type of power supply. Generally, AC power is easy to obtain. 4.2 For voltage specifications, AC220V and DC24V should be given priority as much as possible. 4.3 For power supply voltage fluctuations, +%10% to -15% is typically allowed for AC, while ±10% is acceptable for DC. If these limits are exceeded, voltage stabilization measures must be taken or special ordering requirements should be submitted. 4.4 The rated current and power consumption should be selected based on the power supply capacity. It should be noted that the VA value is high during start-up under communication conditions; indirect-acting solenoid valves should be given priority when capacity is insufficient. 5. Control precision 5.1 Ordinary solenoid valves have only two positions: on and off. When high control precision and stable parameters are required, multi-position solenoid valves should be chosen ； The Z3CF three-position normally open solenoid valve offers three flow states: slightly open, fully open, and closed ； The ZDF—Z1/1 combined multi-functional solenoid valve has four flow rates: full open, wide open, narrow open, and full open. 5.2 Action time: Refers to the time from when the electrical signal is applied or removed until the main valve completes its action. Only our company’s patented multi-functional solenoid valves allow for separate adjustment of the opening and closing times, which not only meets the requirements for control precision but also prevents damage caused by water hammer. 5.3 The leakage values indicated on the leakage volume samples represent the standard economic grade; if these values seem too high, please place a special order. III. Reliability: Unreliability will damage the entire system! 1. Service life: This item is not included in the factory testing procedures and falls under the category of type testing. To ensure quality, choose branded products from reputable manufacturers. 2. Working system: There are three types, namely long-term working system, repeated short-term working system, and short-term working system. All of our company’s standard products are designed for continuous operation, meaning that the coils can remain powered on for an extended period of time. In cases where the valve remains open for a long time with only short periods of closure, an normally open solenoid valve is advisable. When used in a short working schedule with large batch sizes, it can be ordered specially to reduce power consumption. 3. Operating frequency: When a high frequency of operation is required, a direct-acting solenoid valve is the preferred choice for the structure, and alternating current is the preferred power supply. 4. Action reliability: Strictly speaking, this test has not yet been officially included in China’s professional standards for solenoid valves; to ensure quality, it is necessary to choose branded products from reputable manufacturers. In some situations, the number of actions required is not high, but the demand for reliability is extremely high, such as in firefighting and emergency protection – these areas must not be taken lightly. It is particularly important to also use two safeguards in combination. IV. Economy: Being uneconomical means a waste of funds, effort, and even lives. It is one of the criteria considered, but economy must be achieved on the basis of safety, suitability, and reliability. Economics is not just about the price of a product; its functionality and quality, as well as the costs associated with installation, maintenance, and other accessories, should be given priority. More importantly, the cost of a solenoid valve within an entire automated control system, or even within an entire production line, is minimal; however, making a poor choice in order to save a little money can result in enormous losses. In short, cost-effectiveness refers not only to the product price, but also to the performance-to-price ratio and the overall cost-to-price ratio of the product.