How to choose the micro solenoid valve introduction

Instrument design engineers always use a variety of electromagnetic components on the instrument. The choice of these precision components has a great impact on the realization of medical, environmental and analytical instrument functions. Most engineers need to weigh the various application factors to consider the most suitable electromagnetic components. The pursuit of compact size in the instrument has made it necessary for the design industry to use smaller, more durable components. Inappropriate selection may result in instrument failure or failure to function properly. Engineers need to consider the reliability and durability of components, and must consider their lightness, effective flow and low power consumption. This report is a team of experienced application engineers to explain the parameters of the selection of miniature solenoid valves from the design and manufacturing roots. And pointed out that those are the key parameters in the application, also indicating that professional valve application experience will reduce or avoid the doubts caused by the choice.
      
       Ensure reliability and repeatability
       When the instrument design engineer chooses the micro solenoid valve, it is often hoped that the component can be operated repetitively and reliably, especially to ensure the long-term stability and repeatability. It is best to hope that there will be no running fluctuations and exceptions for a long time. It is often the first parameter to screen precision components.
       For example, the selection of the isolation valve used in the blood cell sampling channel and the counting channel usually affects the repeatability of the whole machine. In the high performance liquid chromatography, the quaternary gradient isolation valve needs to have a uniform response time to make it easier to meet the test requirements. Sexuality has an intuitive difference in the detection of sensitivity repeatability.
       Even the early choice of original accessories can lead to serious unpredictable consequences. The later the design flaw is discovered, the higher the modification cost. Because when you need to replace components, you need to repeat a series of tests. Therefore, in this case, engineers generally use components with high reliability, and will pay special attention to the valve production process, quality inspection and test control.
       In particular, the design of the valve directly affects the reliability of the device itself. For example, in an analytical test instrument, the solenoid valve directly contacts the sample reproduct, but most of the miniature isolation valves have an internal rubber material, which may be encountered when contacting the sample reproduct. Swelling. If you do not consider any pre-compensation of the design, then the rubber material will change the parameters and performance of the valve after a long time of use, and even affect the component to work properly, resulting in the problem that the entire instrument can not work. Experienced component designers will consider the application of the valve, especially the compatibility of chemical substances and other practical applications on the valve.

       Ensure a longer service life
       The continuous service life is the first parameter that the valve should consider in most applications, especially in some applications where a longer continuous service life is required. For example, in medical equipment and high-speed instruments, the equipment requires continuous operation, requiring that the number of failures of the device be minimal or even zero, even after a long period of use. Frequent maintenance and replacement of valves is best avoided. The continuous high service life also means that the components have better reliability in complex and varied applications.
       In fact, the high reliability life guarantee is difficult to achieve, experts who have experience in valve design have mentioned that the most troublesome for high service life is to move the closed film, that is, the design of the diaphragm. Whenever the valve is working, the diaphragm will be pulled up by the pull rod. After several million reciprocating motions, the diaphragm pulled by the push rod will be worn. This will happen in most valves. Some manufacturers change the push rod or The diaphragm material is designed to solve.
       Experienced application engineers will consider designing to reduce diaphragm deformation when considering long service life, which will ensure a smoother contact surface and less impact, especially for valves with metal bodies. Both the plastic body and the plastic push rod have better durability.
       Life-influencing factors should also be included, including the application of the fluid, the time the valve needs to be continuously energized, some extreme use conditions, or the application differences caused by various influencing factors. Some manufacturers test the life of 500,000 times, but some manufacturers have already achieved tens of millions of lifetimes.

       Make sure the design is smaller
       Almost every improved instrument needs to be lighter and smaller than the original instrument, so each instrument design engineer needs to consider the size of each component at design time. In some precision or online monitoring equipment, it is particularly necessary to reduce the volume of components, and the reduction of the valve volume can better accommodate non-valve components such as circuit boards and container bottles. The compact body mechanism also reduces the inconvenience of transportation.
       As long as the component size becomes smaller, the design engineer can reserve more space for the rest of the structural design, allowing the device to reserve more functional expansion space. For online monitoring instruments, there are certain specifications for the size. For example, the alcohol tester needs to be able to carry it by hand. The online total phosphorus total nitrogen instrument contains many miniature solenoid valves and power source devices. The size of the solenoid valve has become a major factor in design selection, freeing up the installation space for other components.
       Conventional valves are generally larger than modern valves, and design engineers will find that even though each valve is smaller in size and weight, it can be more advantageous in a complete installation with limited installation space.
       Many conventional valves are still made of stainless steel body, and the new plastic body can significantly reduce weight.
       If you need to get more flow or reduce power, you need to increase the weight of the valve body, and the valve designer needs to get the same performance under the conditions of the required weight and size.

       Ensure that the application’s traffic is met
       As long as the instrument's compactness continues, every design engineer will need the same performance but smaller components. Increasing the flow rate is a critical parameter for miniature solenoid valves. However, parameters that affect the flow rate, such as energy consumption, pressure, and flow rate, are mutually constrained. The Cv (flow coefficient) value is related to the internal channel design of the valve itself. The flow coefficient can reflect the flow design level of the valve itself in one aspect. The Cv of each valve may be the same, but the volume is different; while the volume looks like a similar valve, but the Cv may be far apart.
       When higher flow rates are required, the overall energy and pressure design must be within the user's requirements.
       Experienced instrument design engineers know that even small flow increases can affect a variety of applications. For example, in order to speed up a single test project, the waste liquid or the cleaning liquid should be removed in a few seconds as soon as possible to save the time of occupying the common pressure source of the whole instrument. At these times, the diameter larger than the test pipe is often used.
       Aperture problems often increase the difficulty of valve selection. For example, some modular valves have different distributions of flow rate and pressure resistance due to the asymmetrical distribution of internal inlets and outlets. When designing the flow path of the bottom plate, the direction of the mounting holes of the valve should be adjusted.
       Normally, designers will weigh that high flow rates require as large a hole as possible, but large apertures typically require more energy and the valve body is larger. Therefore, in order to ensure reliability, under the advantage of weight and small volume, it is advisable to select the appropriate flow rate valve body under the corresponding application conditions. The valve body with excessive flow rate will only increase energy consumption and occupy space. Unsuitable for use, it is best to use a suitable aperture for the application to meet the reasonable application flow rate.
Ensure more energy efficient devices
       Energy saving is a very important factor for devices that are compact or portable with solenoid valves. A good miniature solenoid valve needs to optimize the use of electrical energy, while also reducing the weight of the valve body, making full use of the energy per ampere generated by the battery or power supply.
       But in fact many products on the market are still very power-hungry. Valve control In many cases, PWM circuits can be added to save energy. Switching power supplies generally use pulse width modulation (PWM) technology, which is characterized by high frequency, high efficiency, high power density and high reliability. This type of circuit reduces the overall power but can also work with the hold voltage, but the cost is higher. Valve design engineers are often concerned with finding low-energy, more efficient coils, which also require energy savings for the valve, which can increase the space on the instrument and the overall instrument performance.

       Make sure the components match
       Every instrument design engineer has different understanding and understanding of components, and it is impossible to comprehensively choose among many parameters. Professionally know the essentials of product selection of different suppliers, only through the assistance of professional fluid accessories application engineers. Choose from a wide range of models for this application. For example, metric pipe fittings are mostly integer values of 1mm, 2mm, etc., while British or American pipe fittings are mostly non-integer values such as 1.6mm (1/16"), 3.2mm (1/8"), and corresponding fittings or washers. It’s not the same difficulty to reach agreement. Customers often purchase the pipe fittings separately, but can not find the corresponding joints; or use the foreign valves, the domestic fittings are not equipped with the corresponding standard fittings. Even if the system is the same, the thickness of the teeth is different. The purchased components often fail to achieve the sealing effect or the service life is reduced due to the mismatch of the parts.
       The product's homogeneous design reduces the risk of selection and maximizes the match to the individual components of the application.
       In order to better reduce the selection of various miniature solenoid valves and to match the difficulty of each component, fluid fittings product engineers always come up with some novel ideas.
Better reliability and repeatability.
       Each series of Bei'an Fluid Micro Solenoid Valves pays attention to the unified basic quality, and design uniform and high standard repeatability. It can be used in precision medical equipment, pharmaceutical equipment, analytical test instruments and research institutes, and can also be applied to high safety factor requirements. Clinical diagnosis, chromatography industry and dental ophthalmology equipment.
       Longer service life. Under the air medium test condition, the solenoid valve has 20 million continuous service life, which is 10 to 20 times of the actual service life. It has enough service life reserved, especially suitable for high-end and long-length. Time requires the application conditions of reliability. The solenoid valve design adopts special wear-resistant plastic as the push rod, which is light and wear-resistant, and has the least influence on the spring resilience, which maximizes the service life of the push rod. At the same time, this design ensures that the chemical reproduct or temperature compensates for the expansion of the rubber because the spring has a corresponding stroke length adjustment at the bottom.
       Smaller. In addition to the most important reliability advantages, the North Ang fluid solenoid valve generally weighs about 50g. Corresponding to the P20 model body size (approx. 20mm diameter body), it is nearly 15% lighter than other valves, especially suitable for some mobile or compact instruments. The round design guarantees installation space and aesthetics. The closed magnetic field formed by the metal casing prevents magnetic field leakage from interfering with peripheral electronic chip electronics.
       High flow rate. Compared to other solenoid valves, the North Ang fluid solenoid valve is designed to increase flow by 15% at the same aperture.
       Energy saving. Each solenoid valve of Bei'an Fluid can be used for PWM energy-saving circuit. Its own power is 1/2 or 1/3 of other similar products, and it has remarkable energy saving effect of 75%~89% for solenoid valve.
       Specialized matching devices. North Ang fluid covers the advantages of world-class valve body suppliers. There are more than 5,000 types of miniature solenoid valves, and more than 3,000 models of other types of accessories. Solenoid valves and accessories ensure the same delivery cycle and matching between components for a variety of products.
to sum up 
       The choice of miniature solenoid valve needs to be measured according to the actual application conditions and the instrument itself. It is necessary to consider the reliability, durability, weight and effective flow rate under a certain pressure, low energy consumption and professional matching components. Among all kinds of high-end instruments, the solenoid valves that need to be used tend to be higher quality electronic components.