The precision compressed air filter is a device that filters and purifies the compressed air. Generally, the compressed air filter element is composed of fiber media, filter mesh, sponge and other materials. The solid and liquid particles (drops) in the compressed air are intercepted by the filter material and condensed on the surface (inside and outside) of the filter element. The liquid droplets and impurities accumulated on the surface of the filter element are deposited to the bottom of the filter by gravity and then discharged through the automatic drain.
Classification of precision compressed air filters:
Generally, the grades of precision compressed air filters can be divided into pre-filtration, preliminary filtration, fine filtration and activated carbon filtration. The pre-filter generally filters out particles with a diameter of 3-5um, and the primary filter generally filters out particles with a diameter of 0.5-1um and the remaining oil mist content is 1ppm w/w. The activated carbon filter is mainly used to remove odor and oil vapor (oil vapor). The remaining fog content is only 0.003ppm w/w).
Application of precision compressed air filter:
The pre-filter is generally used in the downstream of the compressor (after cooler), and the application requirements are not high. The primary filter is generally used for tools, motors, cylinders, etc. Fine filters are generally used for painting, injection molding, instrumentation, control valves, transmission, stirring, electronic component manufacturing, nitrogen separation, etc. Activated carbon filters are generally used in food and medicine manufacturing, breathing air, gas processing, etc.
The relationship between precision compressed air filter and air temperature:
The temperature of the oil and water contained in the compressed air affects the efficiency of the filter. For example, when the temperature is 30°C, the oil content flowing through the filter is 5 times that of 20°C; when the temperature rises to 40°C, the oil content flowing through the filter is 10 times that of 20°C. Therefore, the filter is generally installed at the lower temperature of the compressed air system.
There are many materials that can be used to make precision compressed air filters, mainly divided into the following five categories:
1. Fibrous filter materials-such as cotton, wool, silk, etc. in natural fibers, glass fibers and chemical synthetic fibers in man-made fibers (polyester, polypropylene, etc.)
2. Filter paper;
3. Powder metallurgy materials-mainly including sintered bronze, sintered stainless steel and Monel alloy;
4. Filter ceramics-mainly quartz, alumina and diatomaceous earth;
5. Activated carbon type of adsorption material.