Whether you are using an in-line filter or an advanced off-line oil recovery system, filter media quality and specifications should consider the OEM’s recommendations, as well as any unique aspects of the environment in which the equipment will operate. such as temperature or pollution limits. In addition to these aspects, there are many other factors that affect oil filtration. These may include oil viscosity, oil system flow and pressure, oil type, components to be protected and cleanliness requirements, and physical filters (size, media, micron grade, dirt holding capacity, bypass valve opening pressure, etc.). .) and the cost of replacing filter elements and related work. By understanding these key elements, you can make data-driven decisions about filtration, extend equipment life, and reduce the frequency of drains and refills.
The maximum differential pressure for full flow elements is determined by the relief valve spring setting. Therefore, a filter with a higher bypass set pressure will be more efficient and last longer than a filter with a lower bypass set pressure.
Engine and hydraulic filters are subject to various temperature changes and pressure fluctuations. If the pleats are not supported and properly designed, the increased pressure drop across the element can cause the filter media pleats to warp or separate. This will invalidate the filter.
When a hydraulic fluid is subjected to high pressure, the oil undergoes some compression at a rate of approximately 2% per 1000 pounds per square inch (psi). If there is 100 cubic inches of oil in the connecting line and the pressure is 1000 psi, the fluid can compress to 0.5 cubic inches. When a directional control valve or other downstream valve is opened under these pressure conditions, a sudden increase in flow occurs.
When large bore and/or long stroke cylinders undergo rapid decompression at high pressure, this pulsating flow can be several times the pump capacity. When pressure line filters are located some distance from the pump outlet or installed in the return line, these free streams can lead to sticking or complete destruction of the filter material, especially in filters of poor design.
Machinery and equipment are subject to operating vibrations and pump pulsations. These conditions remove fine abrasive particles from the filter media and allow these contaminants to re-enter the fluid stream.
Diesel engines emit carbon black during combustion. Soot concentrations above 3.5% can reduce the effectiveness of anti-wear additives in lubricating oils and lead to increased engine wear. A standard 40 micron full flow surface type filter will not remove all soot particles, especially those between 5 and 25 microns.
Post time: May-31-2023
