Purpose of Hydraulic Fluids

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Purpose of Hydraulic Fluids

Power transmission: The primary purpose of any hydraulic fluid is to transmit power mechanically throughout a hydraulic power system. To ensure stable operation of components, such as servos, the fluid must flow easily and must be incompressible.

Lubrication: Hydraulic fluids must provide the lubricating characteristics and qualities necessary to protect all hydraulic system components against friction and wear, rust, oxidation, corrosion, and demulsibility. These protective qualities are usually provided through the use of additives.

Sealing: Many hydraulic system components, such as control valves, operate with tight clearances where seals are not provided. In these applications hydraulic fluids must provide the seal between the lowpressure and high-pressure side of valve ports. The amount of leakage will depend on the closeness or the tolerances between adjacent surfaces and the fluid viscosity.

Cooling: The circulating hydraulic fluid must be capable of removing heat generated throughout the system.