Image Credit:Africia Oil
In order for lubricated machines to function properly, they often require clean and dry oil. Since current maintenance procedures are only capable of targeting approximately 10% of oil contaminants, it is no surprise that up to 80% of all hydraulic and lubricated equipment failures and wear problems arise as a result of oil contamination. To overcome these limitations, various companies and researchers have developed new and improved lubricant cleaning technologies.
Challenges in Cleaning Oil
Two of the most common contaminants that affect oil integrity include particulate and moisture contamination. Particulate contamination can originate from either internal sources or result from ingression that occurs during the machine’s operation. Although various filtration techniques, such as high efficiency (beta rated) filtration, are currently used in many industrial settings, there is still a considerable amount of improvement needed in this area.
Moisture contamination also poses a significant risk to the lifetime and overall functionality of lubricated machines. Although the specific type of oil and temperature play a role in determining how harmful moisture contamination can be, some lubricated systems can fail immediately even when a small amount of excess moisture is present. Moisture contamination typically occurs as a result of condensation reactions, seal leaks, substandard ambient conditions or contamination by the chemicals and water used during equipment cleanup procedures.
Current Oil Cleaning Solutions
In terms of removing unwanted water contaminants from oil, several solutions are available, of which include water-absorbing cartridges, settling tanks, centrifuges and coalescing filter/separators. Water-absorbing cartridges are equipped with a hygroscopic media that absorbs any unwanted moisture or free water contents from oil. While these cartridges are cost-effective solutions, they are typically only applicable for systems that experience continual moisture ingression. Furthermore, water-absorbing cartridges are limited in their ability to effectively remove water that is present in emulsified or dissolved states.
Any excess moisture is able to separate from oil and settle through the use of settling tanks. The efficacy of settling tanks is determined by the size of the tank, its residence time, as well as specific oil characteristics, such as its viscosity or chemical nature. There are several limitations associated with the use of settling tanks, of which include significant size requirements, regardless of whether the tank is being used for small systems, as well as the inability to remove gas or water that is present in emulsified and/or dissolved states.
Both centrifuges and coalescing filter/separators utilize gravitational forces to mechanically separate water contaminants from oil. Both of these oil cleaning solutions are ideal for low viscosity oils that exhibit high water contamination rates. In regard to centrifuges, several limitations prevent this solution from being widely used within the industry. These limitations include the high costs associated with purchasing centrifuge installations, as well as the labor-intensive requirements needed to both maintain and operate these systems.
EPT’s New Approach to Clean Oil
There is clearly an urgent need for adequate methods to remove both water and oil contaminants from oil in lubricated industrial equipment and machines. EPT technologies is one company that has emerged as a leader in developing innovative applications for cleaning oil; these include those that are specifically targeted in addressing the problems associated with electro-hydraulic control (EHC) systems, turbine lubricant varnish, water contamination and filter element upgrades.
In many EHC systems, a preliminary oil analysis is performed to evaluate contamination levels within the system. While useful in theory, these fluid analysis reports are often incorrect in their predictions. To address these weaknesses, EPT utilizes a comprehensive four step approach that includes initial oil analysis, which provides a complete picture of the oil’s current condition. This oil analysis is followed by the use of their specialized Ion Charge Bonding (ICBTM) filters that remove both acids and other dissolved breakdown products, both of which can be the source of valve failures and erosion. The third component of EPT’s approach involves the use of their Total Moisture Removal Nitrogen (TMRTM N2) systems, which utilize a mass transfer mechanism, which is a non-mechanical solution, to remove free, emulsified and dissolved water contaminants from oil. The final component of EPT’s approach to EHC systems involves their Electrostatic Contamination Removal (ECRTM) system, which has been shown to remove up to 90% of particulate contamination below 5 microns, improve oil color and resistivity and reduce air entrainment within the system.
- “Applications” – EPT
- “Removing Water and Particulate Contaminants from Oil” – Pumps and Systems
- “Electro-Hydraulic Control (EHC) Systems” – EPT
- “ECRTM System” – EPT