Hydraulic fluid is the lifeblood of every hydraulic system. A single variety of hydraulic oil is not used with all hydraulic systems. Instead, the most compatible hydraulic fluid needs to be selected by considering physical and chemical properties. When considering the importance of hydraulic oil, the key functions include power generation, sealing, lubricating components, heat transfer and more. Then what will be the outcome if the oil selection is incorrect? The most possible result will be poor performance and the worst case is a complete breakdown of the system. Here, we can analyze in detail, what all are the consequences of wrong oil selection in the hydraulic system.

The hydraulic fluid makes the system run smoothly and safely with minimum applied effort. Viscosity, demulsibility, compressibility, material compatibility, fire & heat resistance, etc… are fluid properties that need to be considered while choosing the ideal fluid for your application. Among these, viscosity has a major role and it indicates the resistance of oil to flow. So, fluid viscosity is considered for all hydraulic systems. When considering the oil viscosity index for fluid selection, higher viscosity oil causes hydromechanical inefficiencies and lower viscosity oil causes volumetric inefficiencies through the leakage. This makes the medium viscosity fluids highly preferred for hydraulic systems. Because wrong viscosity selection will affect both machine performance and service life.

Hydraulics can be used in different sectors, and the system operation and working environment need to be identified before selecting the fluid. What are the base oil types? Petroleum/mineral, synthetic, biobased, and water-based are the different oil types available and additives can be added to this for improving the fluid features.
What happens when the wrong hydraulic oil is selected? As expected, this will be dangerous to your hydraulic system. The below mentioned are important consequences of wrong hydraulic oil selection.

• Properly lubricating the machine components are necessary for improving the hydraulic system performance and service life. Poor lubrication will increase the friction between components which results in heat, wear and associated contamination.
• One of the important reasons for decreased system efficiency is the mistake in oil selection. If the fluid compatibility is not considered while selecting, the desired performance of the system can’t be achieved.
• Heat generation is also a consequence of wrong oil selection. Certain hydraulic oils easily produce heat and this will cause damage to other components due to overheating. Also, overheating will damage the seals.
• When the system uses easily degradable hydraulic oil or replacement of oil is not done regularly, there is a high possibility for varnish/sludge to build up.
• The surrounding environment needs to be considered while oil selection. For example, fluids having a high freezing point can’t be used for outdoor applications in polar climates.

Other oil properties also need to be considered. Like high flashpoints to resist fire, anti-foam agents to control fluid aeration, non-corrosive properties to prevent corrosion, and more.