Filtration of Hydraulic Fluids to Maintain Quality and Integrity
In this article we spoke with Brett Leggitt - Division Manager for SCL’s Richmond, California location about the importance of proper fluid filtration for industrial oils and hydraulic fluid to ensure the optimal health and performance of your heavy duty equipment. Whether you’re powering a large pump at a sanitation facility, a Caterpillar excavator or the turbine of a power generation plant in a refinery, product cleanliness and protection from contamination is essential. When you have a hydraulic system putting 3,000 psi of pressure through whatever machinery you’re using, any microparticulates present could cause your equipment to degrade and corrode, costing you time and money in downtime for repairs and potentially expensive equipment replacement.
Filtering Microparticulates While Also Maintaining Important Additives
Oil or lubricants purchased in bulk from a refinery are automatically put through a 100 mesh filter or screen that blocks gravel, dust, rocks and large particulates for removal  when they are being loaded at the refinery or truck rack. At SCL, all of our trucks have 100-mesh filters in place on our in-line units to protect our pumps and to remove debris from our customer’s oil. Says Brett Leggitt, “All oil has particles in it… sand, gravel, silicon, dirt, dust, atmospheric elements, metals and minerals. Your additives are also combinations of minerals and metals and when you make a refined motor oil you take a base oil and add things like phosphorus, sulfur, zinc, etc. When we perform proper fluid filtration, it’s important to know what we’re trying to filter out and what elements we need to keep, paying close attention to what level we’re filtering at. Different oils cannot be filtered to the same micron level, and in general you don’t want to filter motor oil below 20 microns to avoid filtering out important additives that fight acid buildup in your engine. When it comes to hydraulic oil, we run it through a filter that removes anything larger than 3 microns.”
Kidney Loop Filtration
At SCL, our filtration operations pump 40-50 gallons per minute through a kidney loop filtration system, constantly cycling the fluids after suctioning them from the bottom of the truck, forcing them through a filtration canister and then looping them back again - just like our own kidneys. Different equipment manufacturers specify what micron level they require for optimal lubricant filtration, such as Caterpillar, who requires an ISO Solid Contamination Code of 18/16/13 to remain in compliance with warranty specifications. With a recent filtration project conducted on behalf of a power generation plant at a NorCal refinery we performed an initial oil analysis to assess what kind of elements were present prior to filtration. Beginning with an ISO Solid Contamination Code of 20/18/14 we were able to effectively filter the oil to reach a micron level of 16/15/12. In other words… cleaner oil as a result of proper filtration and pre and post oil analysis.
Protection From Water Contamination
Says Leggitt, “Water contamination is also a huge concern, especially in the past 6 months with the nearly 40” of rain we’ve experienced in Northern California and across the state. Any moisture in hydraulic fluid can have a detrimental effect on the oil and ultimately your equipment, causing rust, corrosion, varnish formation, oxidation, hydrolysis and sludge, so testing for the presence of water in hydraulic oil is extremely important and can be done using a handful of techniques.” The visual crackle test is a relatively simple method that tests for the presence of emulsified water suspended within oil. The presence of this moisture will cause a sample of oil to crackle when heat is applied using a hot plate or with the old fashioned method of a lighter held below a teaspoon sample of oil. If the crackle test is positive, further analysis may be employed to determine the amount of moisture present and the best course of action to take to remove it. Karl Fischer Titration kits are common for determining the presence of water by way of titration - a technique that takes a solution of a known concentration and uses it in contrast to determine the volume of an unknown solution. Vacuum dehydrators are also sometimes used to remove water once moisture has been detected.
Cleaner Oil, Longer Equipment Life
According to Leggitt, “The cleaner you can get the oil, the longer you can extend the life of your equipment. In the filtration we performed for the refinery they required a specific ISO contamination code and “Water by Karl Fischer” reading. With our filtration efforts we were able to take those numbers down to a level below what they had requested.
Refinery Filtration Requirements
- Water by Karl Fischer ASTM D6304 . . . . . . . . . . . . . . . . . . . . . . . . 6304-1.9 47 ppm
- ISO Contamination Code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17/15/12
Post Filtration Levels
- Water by Karl Fischer ASTM D6304 . . . . . . . . . . . . . . . . . . . . . . . . 6304-1.9 45 ppm
- ISO Contamination Code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16/15/12
Preventing Product Contamination With Proper Fluid Filtration + Oil Analysis
Desiccant breathers on your tanks exclude moisture and particles from your oil and in-line filters at the 5-micron level catch harmful dust, minerals, metals, etc from entering your equipment, which in effect, improve performance and extend the life of your heavy machinery - often your organization’s most expensive assets. Proper fluid filtration combined with oil analysis is a winning combination when it comes to preventing product contamination with oil analysis playing an essential role in maintaining the integrity of your machinery with the cleanest oil possible. By conducting oil analysis on your hydraulic fluids once a year on average, you can then turn to filtration, saving money by not having to actually change the oil for longer periods of time. Oil analysis will determine the presence of moisture and wear metals such as tin and copper as well as other contaminants that may be present in heavy machinery. “When a machine is pumping 3,000 psi and you have a small piece of metal going through your system there’s going to be abrasion, possible leakage and your equipment is eventually going to be compromised.”
The Life Extension Method
Whether you’re dealing with manufacturing, power generation, refining, injection molding, agriculture, landfills, recycling facilities, sanitation or re-ecology, across all industrial sectors, proper fluid filtration and lubricant cleanliness is an important part of extending the life of your equipment. The Life Extension Method, or LEM combines a variety of test results to show how component and machine life can be extended through the process of filtering oil to maximize cleanliness. Life Extension Tables and what are known as Life Extension Factors are laid out according to:
- Hydraulic Systems
- Roller Element Bearings
- Moisture
By reducing the particulate matter within hydraulic oil and fluids with proper fluid filtration and oil analysis to acceptable levels you can increase component life accordingly. According to the Life Extension Tables created by Chevron’s ISOCLEAN program for example, by reducing an ISO contamination Code from 21/18 to 15/12 and the amount of moisture in your hydraulic fluid from 2500 ppm to 156 ppm you can successfully increase your component life by a factor of 5, extending the life of your equipment and saving your organization time and money.
In a wide range of industrial sectors, if there’s metal touching metal, oil is involved. At SCL, we’re here to protect and optimize the machines that keep our country moving and we pride ourselves on providing superior logistics and solutions, extensive product and industry knowledge and total performance satisfaction for our customers. As a cost savings strategy, consider performing oil analysis and filtration on your hydraulic fluids and oils for heavy machinery and equipment. For more information on how to conduct oil analysis on your inventory and to prevent product contamination with filtration, contact an SCL consultant today.