The four major causes of hydraulic oil deterioration are:

• Particulate Contamination
• Moisture Contamination
• Acid Build-up
• Oxidation

  These four causes of hydraulic oil deterioration create contaminated oil and viscosity fluctuation, which in turn creates the need for frequent oil changes and/or cleaning. Failure to address these issues results in a myriad of mechanical and operational problems.

Particulates enter the system in a variety of ways. The four main sources are:

Impurities in new oil and contaminants inadvertently introduced when new oil is added to the system.

Exterior pollutants and moisture in air entering via the breather caps.

Particulates entering through seals, along the rams and other moving components.

Wear of internal components generating multiple and geometric growth of particulates.

Filtroil's filtering capability is a combination of high contaminant retention capacity and a steady, slow flow rate. The low flow rate filtering procedure, supplemented with the pressure of the oil from the top of the element, ensures continuous filtration removing silt which because of its size (1–5 microns) is most harmful. This most neglected form of contamination in hydraulic oil is ultra-fine dirt, undetectable by sight, which interacts with moving surfaces causing abrasive wear.

Moisture Contamination

Moisture contamination is derived from condensation, and is normally only a few ounces of water. The Filtroil element will absorb normal moisture levels of 4 to 19 oz., depending on size and type of element, maintaining the amount of water less than 0.03% by volume.

Abnormally large quantities of water in oil are usually the result of breakdown between the heat exchanger and the hydraulic system or some other catastrophic failure. Although it is not the main purpose of our filtration system, Filtroil does sell specially designed water eater elements for the removal of residual water after the system (i.e., water jacket, etc.) has been repaired. These elements fit into our normal housing unit and can be used for emergency situations to absorb up to 30 oz. of water.

The regular Filtroil element consists of rolled filtering paper made from a dense cellulose fiber (C6H10O5). This natural fiber contains a variety of water absorbent hydroxyl groups making it excellent for the removal of moisture.

Acid Build-up

Acids, most commonly sulfuric acid and hydrochloric acid, are primarily caused by the slow formation of chemical acid groups in the hydraulic oil. Although oil additives slow this process, the continuous removal of virtually all moisture and particulate contamination significantly reduces the supply of chemical, physical and catalytic building blocks necessary for acid formation. Filtroil does not affect additives in solution or remove the largest of additive particles of 1/100 micron.

Filtroil limits the acidity of oil continuously at a total acid number (TAN) of 0.1 to 1.5, depending on oil specifications. Manufacturers normally recommend oil change at TAN 2.0 or above.

Oxidation

Oxidation is the chemical bonding of the oil itself with oxygen. As oil oxidizes, the physical properties change and oil loses its lubricity (i.e., its lubricating qualities).

This process occurs in two ways in hydraulic systems.

Rapid oxidation occurs when hydraulic oil is "cooked" in an overheated situation normally brought about by inadequate cooling or an improperly functioning system. Cooked oil is a dirty brown color and machine parts look "varnished." Filtroil cannot directly solve major overheating problems. Once the oil has been totally destroyed by overheating, Filtroil cannot restore it to the original condition, but by removing particulates we do reduce the internal temperature by 4° F to 7° F.

Normal long-term oxidation occurs due to the exposure of oil to oxygen entering through breather caps, make-up oil, and system moisture. Without overheating problems, Filtroil will extend the life of your oil at least 7 to 10 years. Filtroil is able to help both the short-term and long-term situations by reducing the internal operating temperatures by 4° F to 7° F. In addition, Filtroil removes oxidation products and other particles which have the potential of being catalysts for further oxidation.

Viscosity Fluctuation

Viscosity fluctuation is the result of the oil degradation conditions listed above.

Filtroil has attacked the first three reasons for oil deterioration in a direct fashion and has significantly slowed down the process of the fourth. By maintaining cleaner than new oil, viscosity is kept at ±15% of new oil. Removing contaminants, such as oxides and water, Filtroil eliminates the major mechanical causes of lower viscosity and extends the life of the viscosity preservers added by oil manufacturers. These additives are not removed and can continue to fulfill their purpose.

Filtroil Bottom Line