Explanation of the Fluid Characteristics of Basic Equipment for Normally Open Solenoid Valves

As a relatively common device, solenoid valves are used in many kinds of equipment, and most of them are responsible for the flow control of liquids. The filtration principles of liquids fall into two major categories: one category of liquid solenoid valves separates according to the number and quantity of particles, such as blocking, sieving, and surface capture; the other is absorption, that is, adsorbing particles onto the filter device by organic/positive-charge means. Therefore, electronic control valve pharmaceutical factories must select the diaphragm according to actual conditions.

Regarding the characteristics of liquids. For example, the viscosity of the liquid and the organic/positive ion components: for a 3-position 5-way normally open solenoid valve under the same working pressure, the greater the viscosity of the liquid, the slower the flow speed, and when the liquid contacts the membrane, a good filtering effect is produced; in addition, the contact time between the liquid and the membrane/mixing of the pulse valve has a great influence on the filtering effect — the longer the stirring/contact time, the better the filtering effect. In addition, note that the liquid characteristics only affect the adsorption and interception of the membrane and do not affect the size of the particles.

It is related to the flow rate and working pressure during operation. To achieve a good filtering effect, piston-type normally open solenoid valves usually adopt a low-flow method; the smaller the flow, the greater the influence on the filter bed. Practice has shown that the structural movement of the membrane has a great negative effect on filtration; when the membrane structure changes, particles and synthetic fibers will precipitate out of the deep-bed filter, thereby affecting the filtering effect. However, the flow rate/pressure difference has a great effect only on adsorption and a particularly limited effect on standard removal.

Particle type is greatly related to the filtering effect; particles are divided into two types: flexible particles and rigid particles. Under a certain working pressure, for a normally closed one-way solenoid valve, flexible particles will enter the filter membrane and cause a large amount of filter mesh clogging, thereby affecting the filtering effect.