Using hydraulic oil in an air compressor might seem like a good idea, but it can cause serious and permanent damage to your machine. While these two types of oil may look similar, their differences make them incompatible.
Hydraulic oil and air compressor oil have different components and vastly different viscosity characteristics, meaning they do not mix well with each other. To ensure your air compressor’s best performance and longevity, it is important to understand why air compressor oil is specifically designed for use in these machines, as opposed to any other type of lubricant.
What is Hydraulic Oil?
Hydraulic oil is a type of lubrication oil that provides power and flow in machines powered by hydraulic pressure, such as forklifts, cranes, hoists, and others. The purpose of hydraulic oil is to transfer power between components and redistribute the load force evenly, which enables shock absorption and helps reduce friction within the system. When purchasing hydraulic oil for air compressors, selecting the appropriate type for optimal equipment performance is important.
Hydraulic oil comprises base oils and additives that provide different properties depending on the application. It contains several chemical compounds including anti-wear agents, detergent dispersants, anti-foam agents, oxidation inhibitors, corrosion/rust inhibitors, viscosity index improvers and extreme pressure additives to meet specific ISO VG (viscosity grade) requirements.
To avoid risks in using hydraulic oil in a nonhydraulic application like an air compressor or air tools, you can use EPA-approved lubricants certified as “non-toxic” for breathing air machines.
It is important to note that under no circumstance should any petroleum-based product be used in an oxygen system or one intended to be used with medical-grade breathable air since it has carcinogenic properties when inhaled. Therefore it is not recommended to use hydraulic oil in an air compressor.
Is it Safe to Use Hydraulic Oil in an Air Compressor?
Using the wrong type of oil in an air compressor can cause extreme damage to the unit, or even lead to a hazardous situation. The most important factor in determining what kind of oil is best for your air compressor is understanding the operating environment.
Factors such as temperature and noise level will affect the lubricant’s properties, so it’s crucial to choose an oil that is specifically designed for that type of compressor or environment.
Hydraulic oils are not suitable for use in air compressors due to the fact that hydraulic oils are heavier and have higher viscosity (thicker) than ordinary lubricating oils used in air compressors.
Hydraulic oil also has a much narrower range of temperature performance than other, more specialized air compressor oils. Furthermore, while hydraulic oil promotes heat transfer when used in hydraulic pump applications, heat transfer is not desirable when using hydraulics on rotating equipment like pistons and crankshafts of an air compressor since they generate more heat during their operation.
Due to these reasons, it’s generally not recommended to use hydraulic oil in an air compressor. Instead, look for specially-formulated compressed air system fluids designed specifically for your particular model and make of air compressor.
This will ensure proper lubrication throughout the entire system with no risk of problems later on down the line due to incompatibilities between common types of oil and your specific model.
Potential Risks of Using Hydraulic Oil in an Air Compressor
It is not recommended to use hydraulic oil in place of compressor/air tool lubricant in an air compressor as this can present some risks to the performance and life of the unit. Hydraulic oils are designed for use in equipment that does not involve the operation or production of air or gas. Hydraulic oils are generally formulated for very high water content resistance and do not contain detergents, dispersants, or wear-reducing additives, making them unsuitable for air compressor applications.
When used in an air compressor, hydraulic oil, with its considerably lower viscosity than compressor/air tool lubricants, can quickly exit from the head breathing vents on the cylinder head due to entrained ventilation from the compression process.
Upon exiting this vent, the oil can contaminate your plant’s environment causing possible health concerns related to breathing in fumes and potential fire hazards if your air receiver is filled with combustible gas such as propane or natural gas. Contamination of other machinery such as controllers, valves, actuators, etc., with lower viscosity oils can also cause machine failures due to leakage out of their small precision cavities.
The lack of higher tackiness additives may subject bearing surfaces in crankshafts, connecting rods and piston rings, etc., resulting in reduced film strength on these components, which could cause premature failure regardless if break-in procedures were followed closely when first installing them or not.
In summary, it is always best practice only to use manufacturer-recommended fluids such as CMGA’s (Compressor Manufacturer’s Guidelines Association) low-cost AD Pressure Lubricants Grade 3 AMSOIL interceptor synthetic blend hydrocarbon fluid Sfor safe long term performance and protection of your important capital infrastructure investments.
Alternatives to Hydraulic Oil
It can be tempting to use hydraulic oil in an air compressor, but in most cases, this is not the correct type of oil for the job. Air compressors and hydraulic systems are very different tools and use different oils to achieve optimal performance.
Hydraulic fluid is formulated for hydraulic applications and carries a wide range of lubricity properties to work properly with hydraulic components, valves, cylinders and pumps. Using the wrong type of oil can cause premature failure of your air compressor or void its warranty.
On the other hand, air compressors require a thinner viscosity oil that won’t gum up specific tubing or filters used within the system. Due to their lower cost point and quick availability, some opt to use motor oils as substitutes for air compressor fluids like ISO 100-150 grade mineral oil or synthetic lubricants like poly-alphaolefins (PAOs).
The type of oil you use in an air compressor should depend on what’s recommended by your manufacturer before you make any decision regarding which form of lubricant will work best within your system. To avoid costly downtime due to breakdowns caused by incompatible lubricants, check with your manual or contact the manufacturer before selecting a substitute fluid for your compressor.
In conclusion, using hydraulic oil in your air compressor is not recommended. Air compressors can generally run on the regular motor or specialized air compressor oil, depending on your machine’s manufacturer.
The wrong type of oil can damage or reduce the lifespan of many components in your air compressor and impact its performance. Special attention should be paid to your user manual for the correct type of oil for use in your particular air compressor.