4. Hydraulic oil filter element
　　(1) filtration accuracy first, according to the needs of the hydraulic system to determine the cleanliness level of the used stains, and then according to this cleanliness level according to the table to select the filter accuracy. The nominal filtration clearness of the most commonly used hydraulic oil filter element on construction machinery is 10 micron.
　　Since the nominal filtration accuracy cannot truly reflect the filtration capacity of the filter element, the absolute filtration accuracy is usually taken as the diameter of the maximum hard spherical particle that can be passed by the filter under specified test conditions to directly reflect the initial filtration capacity of the newly installed filter element.
　　The main criterion for evaluating the hydraulic oil filter element is the beta value measured by iso4527-1981e (multi-pass test), that is, the ratio of the number of particles on both sides of the inlet and outlet of the oil filter when the oil mixed with standard test powder passes through the filter for several times.
　　This article is organized by dongguan oneness filtration technology co., LTD