Electric valve selection guide shopping tips and necessary considerations

1, control valve selection question: more valve selection knowledge please click to enter: valve selection topic. Currently, the control valve commonly used in engineering are: solenoid valve and electric valve. However, they all have defects in use, such as electromagnetic valve susceptible to foreign body blockage, water resistance, to be long-term maintenance, etc .; and although the motor valve without water resistance, but due to the need for the necessary control circuit, so water vapor erosion effect Life is also a major problem plaguing the promotion. 2, how to overcome the scale of the greatest impact on the use of valves Whether it is solenoid valve or electric valve, the scale will not only cause leakage of the valve, the valve will even affect the normal work, so how to eliminate the impact of scale, it has been the industry generally Concerns. Control valve technology to be involved in the scope is too wide, you can not be here one by one to make it clear, I hope this content also personally check the information. However, due to the design of implementing agencies and the use of different filler material control valve performance is poor or can be summed up in the law: 1, the presence of dead zones in the process will make the process variables deviate from the original set point. So the output of the controller must be increased enough to overcome the dead zone, and only this corrective action will take place. 2, ① the main factors affecting the dead zone. Friction, wandering, shaft twisting, amplifier dead zone. Various control valves are sensitive to friction. For example, rotary valves are very sensitive to the friction caused by high seat loads, so notice this when using them. However, for some types of seals, high seat loads are required to achieve a closed rating. Haha, so, this valve is designed to be very poor, easy to cause a lot of dead zone, which is the impact of the process of bias is obvious, it is decisive. ② wear. Valve wear is inevitable in normal use, but the wear of the lubricating layer is the most powerful, according to our experiments confirmed that lubrication rotary valve only after a few hundred cycles of action, the lubrication layer can be used just about brushes (exaggerated point , Or write a very depressed). In addition, the stress caused by the load will lead to the sealing layer of wear and tear, these are the main factors leading to increased friction. The result? It is to the performance of the control valve devastating! ③, Friction is the main source of friction control valve, the use of different fillers, friction caused by a great difference. ④, the type of implementing agencies also have a fundamental friction, in general, spring film actuator than the piston actuator is good. 3, locator design issues. From the initial thinking of the design, the actuator and the positioner design must be considered together. How to design a good locator? From his important characteristics to know, must be a high gain device. Its gain is made up of two parts: static gain and dynamic gain. The way to increase the static gain is to design a preamplifier. Such as nozzle - baffle device. Then a friend to ask how dynamic gain? Through a power amplifier is obtained, the power amplifier is a spool valve (general). Someone now uses a microprocessor to set up the locator. It looks like the valve will tell us later where he is broken. At that time, it is easy to do maintenance. Closer to home. High-performance locators with both high static and high dynamic gains provide the best overall performance for any given valve assembly in terms of reducing process variability.