One term that can be used to characterize hydraulic lubricants is variety. Hydraulic oils are sold by virtually every oil company and encompass a wide range of viscosities and performance characteristics. There is also a broad range of hydraulic oil quality in the marketplace. Some hydraulic oils are actually sold wholesale at less than $1 per gallon, while certain specialty fluids can command prices of $60 or more.
Hydraulic oils are used in a wide range of applications and in demanding environments such as under the sea and in outer space. They are used in virtually every industrial and agricultural field from manufacturing and farming to mining. All of these lubricants require different performance characteristics.
The most commonly used hydraulic oils are anti-wear (AW) and rust and oxidation inhibited (R&O) oils. There are also biodegradable hydraulic oils that are used in more sensitive areas, as well as fire resistance hydraulic oils that are used where there is a fire safety issue.
High performance hydraulic oils are usually PAO-based synthetic oils such as the AMSOIL AW Series and RC Series or the Mobil SHC 500 Series oils. These oils are characterized by a wide operating temperature range, and in the case of the AMSOIL products, very high wear resistance as is evidenced by low four-ball wear test results. These oils are designed to last several times longer and operate in much higher temperatures than conventional mineral hydraulic oils.
Biodegradable hydraulic oils are made using a vegetable base such as rapeseed or synthetic esters. Rapeseed type oils such as Texaco’s Biostar® have a much shorter useful life when compared to synthetic biodegradable such as AMSOIL TBI, which may last up to 10 times longer.
Fire resistant fluids are also being marketed such as Mobil Pyrogard 53, a synthetic phosphate ester with a flash point of 243 deg. C or 470 deg. F. Note however, that AMSOIL AWH (ISO-32) has a flash point of 244 deg. C or 471 deg. F.
On the lower end of the hydraulic oil spectrum are mineral oils made with paraffin base oils. These oils are not designed for long life and usually have a minimal additive package. These are typically used in systems that have a lot of leaks and can often be found in mining and agricultural applications.
Other mineral hydraulic oils use naphthenic base stocks and have an improved additive system for slightly longer life and better protection.
Synthetic hydraulic oil should be considered as a replacement for mineral-based hydraulic oil due to its higher operating temperature capabilities, reduced wear and increased lubricant life.
AMSOIL has a Hydraulic Oil for Every Application
AMSOIL has a full family of products suitable for hydraulic applications. These products are full synthetic products that offer increased life, lower wear, temperature reductions and energy savings.
AW Series anti-wear hydraulic oils are available in a wide range of viscosity grades for all applications where anti-wear additives are required.
RC Series is a product line with a full range of viscosities and is utilized where R & type oils are recommended.
TBI is our biodegradable hydraulic oil and is suitable in environmentally sensitive applications such as the logging industry or in equipment near water.
RCE is an ISO-10 fluid that can be used in hydraulic applications requiring a light oil.
ATH is our ISO-46 tractor hydraulic fluid, an excellent value for use in mobile hydraulic systems.
Hydraulic System Tips
Keeping hydraulic systems clean is one of the most important procedures that can be done to prolong the life of hydraulic components. Investments in proper filtration technologies to insure clean oil and clean systems are essential to optimum hydraulic system performance. In fact, contamination if the cause of failure 70 to 80 percent of the time in hydraulic systems.
Leaks in hydraulic systems also need to be properly handled. Even small leaks can lead to major oil losses and contamination. All leaks should be repaired no matter how insignificant they may appear.
Water is a common problem in hydraulic systems, in fact, water contamination of 1,000 ppm or more should be addressed immediately. Some common causes of water contamination include a leaking oil cooler and condensation. Replace leaking seals and repair the heat exchanger if necessary.
