Suction Filter: This filter is installed on the pump's suction line to remove residual contaminants from the oil tank and contaminants entering through air vents, protecting the pump. However, to prevent cavitation, pressure loss must be carefully considered. Generally, a 100-200 mesh coarse metal mesh or notched wire is used. Therefore, it is not a filter for controlling the system's contaminant concentration.
High-Pressure Line Filter:Located on the pump's outlet line, it protects against contaminants entering the system. Therefore, it can control the system's contaminant concentration. However, because it is a high-pressure line, it is subject to pump pulsation and pressure shocks, so the material and strength of the filter element must be carefully considered.
High-Pressure Line Filter: Installed in the system to protect hydraulic components particularly sensitive to contamination; also called a terminal filter. Therefore, it often has a smaller filtration particle size than other filters. A large-capacity filter should be selected.
Return Filter:Located on the system's return line, its function is to capture contaminants generated or introduced into the system before they return to the oil tank. Therefore, it is the most effective and important filter for controlling the concentration of contaminants in the system. Although it is a low-pressure pipeline, pulsations or pressure surges may occur depending on the operating conditions of the transmission device, so the material and strength of the components must be carefully considered.
Circulation Filter: Located on the return oil line of the oil tank circulation system, it is often used when strict cleanliness is required due to the large system capacity. Even when the system is not operating, it can capture contaminants in the oil tank, thus achieving the best efficiency in reducing contaminant concentration. It also has a cooler installed, offering advantages such as simultaneous cooling and easy maintenance. However, it requires a dedicated pump and motor, resulting in high costs.
Air Filter: Located on the oil tank, it prevents contaminants from entering the oil tank with air due to changes in oil level. Therefore, the filtration accuracy must be equal to or higher than that of a dedicated filter, and the capacity must have sufficient margin to prevent negative pressure in the oil tank due to pore blockage, which could cause cavitation in the pump. Special attention should be paid to this in harsh environments.
