The effect of the hydraulic filter is to filter various particulate impurities in the hydraulic system. Its origin mainly includes: mechanical impurities that remain in the hydraulic system after cleaning, such as rust, casting sand, welding slag, iron filings, paint, paint skin, and cotton yarn debris. Dust that enters the dust ring, etc .; impurities that occur during the operation process, such as debris formed by the hydraulic effect of the seal, metal powder that occurs due to relative wear, colloid, asphaltene, and carbon residue caused by oxidative transformation . After the above impurities are mixed into the hydraulic oil, the circulation effect of the hydraulic oil will cause damage everywhere, seriously affecting the normal operation of the hydraulic system, damaging the oil film between the relatively moving parts, and shortening the service life of the equipment.
Usually the hydraulic filter is mainly composed of filter element (or filter screen) and shell (or skeleton). Many small gaps or pores on the filter element constitute the flow area of the oil. Therefore, when the scale of impurities mixed into the oil is larger than these small gaps or pores, it is isolated and filtered out from the oil.
Technical requirements for hydraulic filters:
(1) The filter material should have a certain mechanical strength to ensure that it will not be damaged due to the effect of hydraulic pressure under a certain working pressure.
(2) At a certain working temperature, the pressure should be stable and durable.
(3) Excellent corrosion resistance.
(4) The structure is as simple as possible and the standard is compact.
(5) Easy to clean and maintain, easy to replace the filter element.