The hydraulic filter shall have corresponding mechanical strength to ensure that it will not be damaged by hydraulic pressure under working pressure. Under the working temperature, the performance shall be stable, with enough durability, good anti-corrosion ability, simple structure and compact size. The cleaning and maintenance are quite convenient. It is convenient to replace the filter element. At the same time, the cost is low.
The working principle of hydraulic filter is relatively simple. The hydraulic oil enters the line to the filter from the left side, flows from the outer filter to the inner core, and then flows out.
When the external filter is blocked, the pressure increases. When the opening pressure of the relief valve is reached, the oil enters the inner core from the relief valve and then flows out from the outlet. The accuracy of the external filter is higher than that of the internal filter, which belongs to the primary filter. Test method of hydraulic filter: at present, relevant standard iso4572 has been widely used to evaluate "multiple pass method of hydraulic filter element filtration performance". The experimental contents include the determination of the pressure difference of the filter element and the filtration ratio (β value) of different sizes. The multi-channel method simulates the actual working state of the filter in the hydraulic system. The pollutants constantly invade the system oil and are constantly filtered by the filter. The unfiltered particles are returned to the tank and filtered again.