Lubrication oil is vital to all internal combustion engines. Unfortunately, lubrication oil has two major negative environmental impacts:
The following Questions & Answers explain how ECO MicroFilters provide a green technology, which builds sustainability and reduce costs.
What is Sustainability?
Sustainability is defined as a product or service which meets the needs of the present without compromising the ability of future generations to meet their own needs.
How is Sustainability Measured?
Sustainability is measured by the environmental, economic, and social impacts over the life cycle of the product or service. Environmental impacts include hazardous discharges, greenhouse gas emissions, use of non-renewable resources, and the amount of energy consumed. Economic impacts include the direct and indirect financial costs associated with the product or service. Social impacts include whether or not the product or service disproportionately impacts one or more sectors of the population and whether the production, use, and disposal of the product or service conform to community norms and national objectives.
Why Does Sustainability Require Life Cycle Analysis?
Life Cycle Analysis, “LCA,” provides a complete evaluation of the environmental, economic, and social impacts of a product or service over the life cycle of the product. Often the initial cost of a products or service may be higher but over the life cycle of the product or service, the overall costs may be less. For example a hybrid bus has a higher initial cost than a diesel powered bus of the same size, but over the life cycle of the vehicle, the lower operating cost of the hybrid bus results in an overall lower life cycle financial cost. In addition, the hybrid bus will produce fewer greenhouse gas emissions, conserve non-renewable fossil fuels, and reduce the consumption of foreign petroleum products, a national objective.
How Can Engine Lubrication Become More Sustainable?
To improve sustainable lubrication requires using less lubricating oil. To accomplish this, oil drain intervals must be extended. This requires good oil chemistry and better engine filtration.
Do Modern Lubricating Oil Formulations Support Sustainability?
Yes. The chemical formulations of modern crankcase lubricating oils designed for diesel, gasoline, and natural gas engines have improved dramatically in the last several decades. In particular, diesel oil has improved significantly. The current American Petroleum Institute, API CJ-4, is a sustainable oil formulation.
Do Full-Flow Filters Support Sustainability?
No. Even the most chemically advanced lubricating oils cannot remove the hard physical particles in the oil film. Engine filtration is required to keep the oil clean; however, engine full-flow filers do not remove microgrit, the small particles which cause the majority of engine wear. While there have been major advancements in lubricating oil formulations, in modern engines crankcase filtration efficiency is essentially the same as the days of old CD and CE oil formulations. Filtration efficiency has not kept pace with the advances in lubricating oils.
How Can Sustainable Lubrication be Achieved? Lubrication, while vital, has two major negative impacts; it creates significant amounts of hazardous waste and consumes fossil-based petroleum oil. By reducing the amount of lubricating oil used in an engine each year, sustainability will be improved. For example, if a transit fleet has a 6,000 mile oil drain interval, to reduce the hazardous waste oil by 50% and conserve 50% more petroleum based lubricating oil, the oil drain interval must be doubled from 6,000 miles to 12,000 miles, while maintaining oil chemistry and keeping particle contamination at or below the level of oil at 6,000 miles, as measured by the oil’s ISO Code levels.
What Impact do Greenhouse Gases Have on Global Warming?
The Intergovernmental Panel on Climate Change (IPCC) reports that most of the global warming of the Earth’s atmosphere observed since the mid-20th century has been caused by human created increases in greenhouse gases, especially carbon dioxide, CO2. Burning fossil fuels accounts for about 75% of the increase in CO2 over the past twenty years, such as the fossil fuels burned by automobiles, cars, trucks, and buses.
Can ECO MicroFilters Help Reduce Greenhouse Gases? Yes. Microfiltration keeps lubrication oil cleaner, which reduces friction and wear in the engine’s moving parts. Reducing friction increases fuel efficiency by approximately two percent (2%) or more. Burring less fuel reduces carbon dioxide, CO2, and air particle emissions.
Can ECO MicroFilters Reduce Particule Pollution?
Yes. Internal combustion engines produce chemical pollution, such as carbon dioxide, CO2, and particulate matter (PM) pollution. In California, the EPA has designated several large areas as “non-attainment zones” for one or more pollutants. Microfiltration improves engine efficiency, improves fuel economy by 2%, which reduces the amount of pollution discharged by engines by 2% or more. Using less fuel results in less pollution.
Why is Source Reduction Important for Sustainability?
The Pollution Prevention Act of 1990, US Code 42, Chapter 133, states that “Source reduction is fundamentally different and more desirable than waste management and pollution control… “The Congress hereby declares it to be the national policy of the United States that pollution should be prevented or reduced at the source whenever feasible….” Recycling hazardous materials, such as crankcase oil, toxic industrial waste and chemical waste, is fundamentally more costly and complex than recycling non-hazardous materials. In California, used crankcase oil is classified as a hazardous material.What can I do?
Why is Engine Lubrication Necessary?
The largest use of lubricants is to lubricate the parts in internal combustion engines. The lubricating oil is pumped between the moving parts, forming a thin oil film, which coats and protects the moving parts from directly touching other moving parts. The piston ring traveling at approximately 65 miles per hour up and down the cylinder wall is separated from the cylinder wall by a thin, invisible lubricating film approximately 3 microns in depth. Without the oil film, the rapidly moving piston ring will make direct contact against the cylinder wall, causing extreme heat and friction, as it scrapes and drags against the cylinder wall. Catastrophic engine failure will result within a few minutes without an oil film separating the piston ring from the cylinder wall.
Seizing the Engine -- Can the Engine Operate Without Lubricating Oil?
No. In normal engine operation the bare metal surface of the piston ring never touches the bare metal surface of the cylinder wall. A micro-thin oil film prevents the moving parts from coming in contact with each other. Without this vital oil film, a rapid, catastrophic sequence results -- the engine’s piston rings will begin to score against the cylinder wall, causing a mass of aluminum, iron, and other metals to quickly form, which forces the piston rings into their groves, thereby allowing the combustion pressure to dissipate without pressing down the cylinder and the loss of engine compression. The loss of compression and the heavy drag caused by the badly scored parts scrapping against each other results in an immediate loss of power. This is referred to as “seizing the engine.” Repair of a seized engine is costly. It requires either a major engine rebuild or replacing the engine.
Why Do Engine Oils Need to be Changed?
There factors impact the useful life of lubricating oil:
What is Crankcase Microfiltration?
Crankcase microfiltration is a green eco-friendly strategy to build sustainability and reduce costs by continuously recycling crankcase oil through a microfilter as the engine operates. This provides highly desirable point-of-origin pollution control by recycling the oil in the engine compartment to remove particle contamination as it is created by the engine or ingested from the atmosphere. ECO MicroFilters capture the 1-10 micron clearance-sized particle microgrit contaminants.
ECO MicroFilters are installed in the engine compartment. An input hose brings dirty oil from the engine to the microfilter. An output hose returns the micro-cleaned oil back to the engine crankcase. The device is installed in the by-pass mode, that is, the oil stream is not in series with the full-flow filter. The small microfilter oil stream is in parallel with the full-flow oil stream. On the top of ECO MicroFilters are oil sample valves, which provide a convenient and accurate method to sample the oil circulating in the engine while the engine is operating. The sample valve provides a sample of the unfiltered oil pumped from the engine before the oil is filtered through the microfilter cartridge.
Can the Engine’s Current Filtration Support Doubling the Oil Drain Interval?
No. The engine’s current full-flow filter only provides absolute filtration down to approximately 35 to 40 microns. Full-flow filters do not remove the harmful 1-10 micron particle microgrit, which cause the majority of the engine’s wear and friction and depletes the oil’s additive pack.
How Can Crankcase Filtration Be Improved?
Crankcase filtration can significantly improve filtration and removal of harmful microgrit.
Do ECO MicroFilters Replace the Engine’s Full-Flow Filter?
No. The full-flow filter is not modified. It remains in operation as designed. The crankcase microfilter is added to the lubrication system in by-pass mode and is not in the same path as the full-flow filter.
How Do ECO MicroFilters Compliment the Full-Flow Filter?
By analogy, in a full-range speaker system, there is a woofer designed to handle the lower frequencies and a tweeter designed to handle the higher frequencies. With ECO MicroFilters installed the full-flow filter continues to capture the larger particle contaminants 35 microns and larger with absolute efficiency, while the crankcase microfilter is designed to capture particles with absolute efficiency from 10 microns down to 2-3 microns or less, which is the size of bacteria.
Can ECO MicroFilters Support a 50% Reduction in Hazardous Waste Oil?
Yes. Several fleet demonstrations demonstrate that the oil drain interval can be doubled with microfiltration, which will reduce both hazardous waste oil production and the consumption of petroleum based lubricating oil by 50%. Better filtration will allow the fleet to take full advantage of today’s superior new oil formulations.
What Size Particles are Captured in a Microfilter?
The crankcase microfilter is designed to operate with high efficiency in the 1 to 10 micron range. One micron is equivalent to .000039 of an inch. Particles in the 1-10 micron range are invisible to the unaided human eye. A person with good vision can see down to approximately 40-50 microns. The 1-10 micron range is the invisible range of the oil films between the moving parts. (See below, Clearance Size Particles, CSP.)
As illustrated below, there is an enormous difference between a 35-40 micron particle, the smallest particle captured by the full-flow filter with absolute efficiency, and a 2-3 micron particle, the size of bacteria, which is captured by the crankcase microfilter. A 3-microns size is the distance between the engine’s rapidly moving piston ring and the cylinder wall.
What Are Clearance-Sized Particles, CSP?
Particles in the oil film moving within the clearances between the moving parts are Clearance-Sized Particles, CSP. The majority of the clearances between the engines' moving parts are between 1 to 10 microns, hence, CSP are primarily in the 1 to 10 micron range. The CSP causes the majority of engine wear and friction. The reason that CSP are harmful is that that are small enough to enter into the clearances between the moving parts and large enough to be forced into contact with the surfaces of the moving parts, causing wear and friction. CSP have been called "liquid sandpaper" to describe the insoluble abrasive slurry of micro-particles, which is continuously re-circulated between the moving parts, causing additional wear and friction within the engine¡¯s moving parts, such as the piston rings and cylinder wall, rod bearings, and the piston pin bushings.
What are the Sources of Particle Contamination?
The three major sources of particle contamination are:
(1) Engine operation. All engines -- whether fueled by diesel, bio-diesel, LNG, CNG, or gasoline -- create CSP through the movement of engine parts, creating wear metals, which build up in the oil film. Abrasive CSP is continuously re-circulated, producing more wear. The more CSP, the fasters the parts wear.
(2) Fresh oil. Even fresh oil contains particle contamination, especially when the oil is stored in a central tank and pumped through long hoses into the crankcase. To the naked eye, the fresh oil¡¯s yellowish-green or golden-brown appearance looks "clean." Since the lower limit of human vision is approximately 40-50 microns, the harmful bacteria-size 1-10 CSP microgrit is invisible.
(3) The air. There are invisible CSP particles in the air, such as the silicon dioxide particles in ash from smoke stacks where coal is burned. Particle contamination is especially dangerous in high dust environments. Silica particles are extremely harmful because they are harder than engine parts. High levels of CSP silica is a major cause of wear and engine damage.
Do Full-flow Filters Remove CSP?
No. Engines have at least one full-flow filter. It operates in-line with a high oil flow rate, typically 12 to 15 gallons per minute at 170-200 degrees with 25 - 65 psi. The full-flow filter is directly between the oil pump and the lubricated parts. All the oil from the oil-pump must pass through the full-flow filter before it enters the engine to lubricate and cool the rapidly moving parts. To avoid starving the engine of lubricating oil, the filter media must be relatively porous and is usually made out of synthetic materials. If the full-flow clogs, the engine¡¯s bypass safety valve opens, which take the full-flow filter "off-line" to allow all the oil to flow to the engine without passing through the full-flow filter. Of course, when the safety valve takes the full-flow filter "off-line," there is no engine oil filtration. Full-flow filters can filter down to approximately 30-45 microns with absolute efficiency (¡Ý 98.7 %) but can not prevent the buildup of 1-10 micron contamination.
Do Microfilters Remove CSP?
Yes. The design of the proprietary ECO MicroFilters device is different that the full-flow filters. The microfilter element contains large quantities of very dense, media and a gradient-flow structure. It operates at approximately 0.2 -.4 GPM. The ECO MicroFilters are not in-line, that is, it is not directly in the path between the oil pump and the lubricated parts. ECO MicroFilters operate in by-pass mode, returning the clean oil to the crankcase.
Does CSP Shorten Engine Life?
Yes. General Motors published a SAE report on the relationship between small micron particle contamination and engine life. The test evaluated the impact of cleaner oil on engine life. The GM study reported that when the lubrication oil is filtered down to 7 microns, engine wear is minimized and relative engine life is more than five times longer.
How Do ECO MicroFilters Reduce Operating Costs?
When an ECO MicroFilters device is attached to the engine, the oil is continuously recycled through the microfilter. When the microgrit is continuously filtered out of the oil, CSP does not build up, as measured by the oil’s ISO Cleanliness Codes at or greater than 4 microns (≤ 4mµ) based upon laboratory particle count analysis. Clean oil reduces costs in two ways: (1) it reduces the annual costs of oil service by extending the oil drain interval. This reduces costs for lubrication oil, labor, shop time, and oil service parts and supplies; and, (2) Engine wear is reduced. The life of the engine is doubled, even when the oil drain interval is extended because the clean oil reduces engine wear, even at extended oil drain intervals. This is especially important to fleets because the cost to rebuild or replace sophisticated modern engines is higher than the cost to replace or rebuild an older pre-EGR diesel engine.
What is the ECO MicroFilters Return on Investment?
The ROI is generally less than twelve months. Often ECO MicroFilters pay for itself in 4 to 6 oil changes, depending on service duty and other oil service costs. The cost savings for transit buses range from approximately $350 per year to $1,000 or more per vehicle/year depending on the equipment and service duty.
How Can I Determine the ROI for Our Fleet?
Our ECO MicroFilters team will provide without cost a fleet savings projections for any fleet with 50 or more vehicles. Please contact us. We will provide a custom fleet cost savings analysis based upon your specific equipment, labor rates, costs, and service duty.
What are the Preventative Maintenance Benefits?
A fleet can reduce approximately one-half of its oil services and provide better engine protection. Reducing the time in a scheduled maintenance for oil “pit trips” saves time and money, and allows the fleet supervisor to assign his or her skilled professionals to higher maintenance tasks. This improves facility utilization and allows mechanics to work on higher priority maintenance issues.
Will ECO MicroFilters Reduce Costs in Natural Gas and Diesel Engines?
Yes. ECO MicroFilters will reduce costs in any engine, including Compressed Natural Gas (CNG), Liquid Natural Gas (LNG), diesel, bio-diesel, gasoline, and alternative fuel engines. Modern engines operate at higher combustion chamber temperatures and at closer tolerances. The closer tolerances require cleaner oil, free of CLP contaminants. The benefits of micro-clean oil are universal with all engine fuels.
Do Microfilters Reduce EGR Lubrication Costs?
Yes. Exhaust Gas Recirculation (EGR) is a NOx (nitrogen oxide and nitrogen dioxide) reduction technique. EGR engines discharge less soot into the air and reduce NOx. Microfilters are ideally designed to remove the higher levels of soot in EGR engines, producing major cost savings by keeping the oil cleaner, longer.
What is the Relationship between Particle Contamination and Engine Wear?
As discussed earlier, General Motors published a SAE technical study on the relationship between level of particle contamination and engine life. The full-flow filter removes particles down to approximately 40 microns. As filtration is increased to down to 30, 20, 10, and 5 micron, the life of the engine components more than doubles.
ECO MicroFilters remove particles contaminants from 1 to 10 microns at high efficiency and down to 4 microns with absolute efficiency with high retention, which allows them to be used for a full oil drain interval at high efficiency without clogging.
What are Wear Metals?
As engines operate, engine wear and friction sheds small amounts of wear metals into the oil. To build engines, several different types of metals are required, including aluminum, iron, and lead. As the engine wears, small amounts of aluminum, iron and lead build up in the lubricating oil.
Will the Rate of Wear Metal Per Mile Decrease with ECO MicroFilters?
Yes. ECO MicroFilters decrease the wear metal rate per mile. In one controlled test on twenty-five transit buses, the rate of wear metal production in buses equipped with microfilters was reduced to approximately half the rate per mile of wear metal production produced in the control buses without the microfilters. These fleet findings correlate with the GM report that reducing particle contamination will reduce engine wear.
How much is the Source Reduction of Hazardous Used Oil?
ECO MicroFilters source reduction is 50% or higher. The amount of source reduction depends on the amount of engine oil and the number of times the oil is changed per year. As an illustration, in a fleet of 100 transit buses with 12 oil changes per year and 9 gallon engine sumps, the reduction would be approximately 71 gallons per bus and 7,100 gallons per year for the fleet.
How Much Conservation of Engine Oil is Achieved?
Source reduction of hazardous waste oil is directly connected with reduced lubricating oil consumption. For every gallon of hazardous waste oil which is not created, one gallon of non-renewable petroleum based lubricating oil is conserved.
What Are the Benefits of Clean Oil?
The benefits include lower engine friction and wear, longer engine life, and longer lubrication life. However, it is not correct to assume that fresh oil is clean or that the air is clean unless the fresh oil and the air is microfiltered before entering the engine crankcase.
Is Fresh Oil Clean?
No in most cases. As previously discussed, to the naked eye the clear, yellowish-green or golden-brownish oil looks clean. Since the lower limit of human vision is 40-50 microns, the harmful 1 to 10 micron microgrit is not visible. Looking at Fresh Oil cannot determine if the oil is clean:
"Contrary to poplar belief that "fresh" oil" is clean, new oil is often very hazardous. It may ship dirty from the supplier, becomes contaminated in storage, or become contaminated during transport to the machine." (Oil Analysis Basics, Drew Troyer and Jim Fitch, Revised 2001, Noria Corporation, page 19.)
Is Fresh Air Clean?
No. According to Troyer and Fitch, many small micron particles are in the air. The authors state that silica air particles are harder than the metal parts in the engine ¨C harder than a hacksaw blade, which is harder than engine parts. The first defense from air contaminates entering the lubrication oil is a good quality air filter and good engine seals. However, even with these precautions, some air-borne contaminants will enter the lubricating oil. The second defense is microfiltration to remove the hard particles as they enter the oil.
Can Fresh Oil from one Garage be Dirtier than Fresh Oil from Another Garage?
Yes. In general, oil in sealed smaller containers is cleaner than oil stored in fleet storage tanks. The oil in some garage storage tanks can have up to twelve million particles per 100 milliliter at 4 microns (ISO 24). Other garages are filling their equipment from sealed container "fresh oil," which can have as little as one hundred thousand particles per 100 ML at 4 microns (ISO 17). In other words, the oil in the storage tank is 120 times dirtier than the oil in the sealed containers. This is particularly disturbing when the oil reaches a level of ISO 21, approximately 1,500,000 particles per milliliter at ¡Ü 4 microns. At this level of particle contamination many professionals believe that an oil change is required. If filled from a "dirty" storage tank with ISO 22 to ISO 24 oil, the "fresh oil" added to the engine would be two, four or up to ten times dirtier than the recommended oil change level.
Does Crankcase Microfiltration Provide a Second Line of Defense?
Yes. If particle contamination enters the crankcase from unfiltered "fresh oil" pumped from a storage tank or "fresh air" which enters the engine through a defective seal or damaged air filter, ECO MicroFilters provides a second line of defense against engine damage by removing the particle contaminates from the lubricating oil.
Can the Benefits of Clean Oil Be Objectively Quantified?
Yes. Laboratories measure particle contamination using several different methods. Once the number of particles at a given micron size is determined through laboratory analysis, the number of particles is converted to the ISO 4406 ratings from the International Organization for Standardization (ISO).
Do ECO MicroFilters Provide Benefits When Used with Premium Oils?
Yes. As stated above, no oil can clean itself of physical contamination. When a synthetic oil or other premium oil becomes physically contaminated, the oil should be discarded to protect the engine even if the oils is still chemically viable (viscosity, TBN, etc.)
It has been said that "premium oils beg for better filtration" to achieve the full potential of the premium oil. Premium oils with more aggressive detergent qualities will clean up dirty engines, dissolving the sludge and other deposits, releasing more particles into the oil. Without microfiltration, changing from standard oil to premium oil can produce unintended consequences. The high detergent qualities actually can make the oil dirtier as the built-up sludge and other deposits begin to dissolve and are suspended in the oil. Physically removing clearance level particles through microfiltration will capture the added contamination dislodged by the increased detergents. In time, premium oils and ECO MicroFilters will reduce sludge and other deposits from a dirty engine.
Can Microfiltration Reduce EGR Engine Operating Costs?
Yes. In an Exhaust Gas Recirculation engine, ("EGR"), the EGR valve re-circulates exhaust gases into the intake stream. These gases displace some of the normal intake charge. This chemically slows and cools the combustion process by several hundred degrees, thus reducing NOx formation. Unfortunately, the EGR process also increases the amount of physical particulates in the lubricating oil, which results in higher lubricating costs. In some cases, without microfiltration, the distance between oil changes is reduced. In other cases, the crankcase capacity is increased to hold more oil for the added particulates, which increases the cost of every oil change. In either case, lubrication service operating costs are increased. ECO MicroFilters will keep the oil cleaner, thus improving the quality and useful life of the oil, which provides better engine protections and extended miles between oil drains.
Are ECO MicroFilters Easy to Service?
Yes. One of the benefits of ECO MicroFilters is their maintenance friendly, easy to service devices. ECO MicroFilters are passive, non-mechanical devices, without electrical or vacuum components, and are extremely rugged. They require only a few minutes to change the cartridge.
Can Major Fleet Efficiencies Benefits Be Achieved?
Yes. For a fleet of 100 large vehicles (transit buses, cement mixers, freight haulers, etc.), ECO MicroFilters can eliminate one-half of the annual oil services. On the first oil interval after an oil change only the high efficiency cartridge is changed, a process which only takes a few minutes. On the second oil interval, the oil is changed, the full-flow filters are changed, and the ECO MicroFilters cartridge is changed.
How Much Time Can Fleets Save?
A 100-vehicle fleet with 1,200 oil changes per year can reduce the oil changes by 50% from 1,200 per year to 600 per year with ECO MicroFilters. With the time saved from eliminating 600 oil changes per year, staff can be reassigned to other maintenance tasks. In addition, more vehicles can be cycled through the garage each year due to the savings of time in the garage. That is 7,200 fewer oil changes over the 12-year transit bus life cycle. In the case of smaller commercial vehicles t of 100, where the drivers take the vehicles to an oil change facility, thereby taking both the vehicle and the driver out of services, the cost of an oil change is dramatically higher.
What is the Difference Between a "Bypass Filter" and a "Microfilter"?
The term "bypass" refers to how the device is attached to the engine. The term "microfilter" refers to the quality of filtration provided by a device. A by-pass filter device is installed in parallel (by-pass) with the output stream from the oil pump. When a filter device is installed in the "bypass" mode, the stream is parallel with the main oil flow. A by-pass filter device is not a true microfilter unless it can provide high micro-cleaning beta ratio efficiency and high particle retention, such as ECO MicroFilters.
What is the Beta Ratio?
The "Beta Ratio," also referred to as the "Filtration Ratio," is a measure of the filter¡¯s capture efficiency at a specific micron size. The Beta Ratio is calculated by dividing the number of particles before filtration at a certain micron size (example, 10 microns) in the upstream oil stream, by the number of particles after filtration at that micron size in the downstream oil stream.
How does Filtration Efficiency Correlate with Beta Ratios?
The filter efficiency, called the Capture Efficiency Percentage (%), is determined by this formula (Beta -1/Beta) X 100. This produces the filter¡¯s efficiency, called the Capture Efficiency Percentage (%). For example, a Beta Ratio of 14 equals 93% efficiency, a Beta of 50 equals 98%.
What does "Absolute" Filtration Mean?
The Filter Manufacturers Council, Technical Service Bulletin 89-5R3, defines "Absolute" filtration as achieving an efficiency of 98.7% at the stated size, and "Nominal" filtration as achieving an efficiency of 50% at the stated size. ECO MicroFilters provide cartridges capable of absolute filtration over almost the entire CLP range of 1 to 10 microns.
What does "Filters down to 2 Microns" Indicate?
By itself the phrase, "Filters down to 2 microns" does not provide sufficient information to evaluate the filter's performance. The device could be only 8% efficient at 2 microns or 90% efficient at 2 microns. Filtration claims must include an efficiency rating, such as a Beta Ratio or efficiency percentage; for example, 88% efficient at 2 microns. One of the standard tests to determine the Beta Ratio and filtration efficiency percentage is the SAE J1858 Filter Element Multi-Pass Test.
What Are Types of Supplemental Filters Are Available?
There are three types of devices:
What is Gravity-Feed Centrifuge?
The centrifuge uses a gravity-feed to return the oil to the crankcase. Technically, the centrifuge is not a filter. It is a mechanical particle separator, which separates out certain particles by rotating (“spinning”) at high speeds to produce a centrifuge action. In large commercial centrifuges, an electric motor and control mechanism maintains the centrifuge speed at a consistent, optimum rotation speed. In the typical centrifuge installed in truck, bus, and automobiles, there is no electric motor or speed control to maintain a consistent optimum spin rate. Instead, the speed varies with the engine oil pressure and the volume of oil from the engine. One problem is that many vehicles, such as transit buses, garbage trucks, or mid-and smaller size trucks used for deliveries in urban environments, do not have consistent engine pressure. A transit bus, for example, will go from idle to major acceleration several times an hour. The oil is sprayed onto a rotating outer bowl, where oil particles are pressed against the bowl. The bowl must be cleaned to remove the particle accumulation. In addition, the device must be removed and partially disassembled to clean the bowl, using a cleaning solution, a process requiring extra time and labor.
Centrifuges have three disadvantages: Filtering efficiency is not constant, installation is difficult, and centrifuges require more maintenance than other devices. Filtration efficiency is lower when vehicles operate in stop-and-go traffic, when the strain on the engine is higher and particle contamination is high. Filtration efficiency is higher when vehicles operate at relatively constant highway speeds, where engine strain is lower and particle contamination is lower. The lower cleaning power during idling and stop and go traffic is a problem for vehicles operated in city traffic, such as city transit buses, with frequent low-speed idling during passenger stops. It is especially problematic in hot weather on transit buses, due to the increased parasitic demands from the air conditioning compressor and generators to cool the bus and usually higher passenger loads. At this time when the engine is under its greatest strain, the centrifuge’s cleaning power is at its lower efficiency. Second, centrifuges are Gravity-Return devices, which are more difficult to install than a canister device. The centrifuge must be installed vertically and most designs require a vacuum connection to the vehicle’s air supply system for the centrifuge’s control mechanism. Third, cleaning a centrifuge device is the most time consuming of all devices, which increases labor costs. A mechanic must remove and clean the centrifuge bowl in special solvents to remove the caked up particles and eventually, the centrifuge’s moving parts also need to be serviced. This adds time, labor costs and creates a new form of contaminated waste in the cleaning solvent. In addition, centrifuges are mechanical devices, which require more maintenance than passive devices.
What is a Canister Filter?
Canister devices are Pressure-Return devices. Some canisters are one-piece designs, similar to a full-flow filter, enclosed in a thin metal housing, designed to be thrown away after one use. Other canister designs consist of a permanent canister and a disposable cartridge. Canisters are passive, non-mechanical devices, where particles are trapped in a disposable cartridge. Canisters vary in size, filter efficiency, and cartridge retention capacity. Canisters are easier to install and less expensive to maintain. Inside the metal canister housing, there is a removable filter cartridge. The early canisters were not very efficient. These early canisters often used paper towels for media, had limited cleaning power in the CLP range and media structural integrity problems. In addition, the early paper-towel canisters were very large, some retaining up to two gallons of oil. The major difference among the canister microfilters can be found in the design of the cartridge. ECO MicroFilters use 16-gauge steel exterior canister housing. Inside the canister there is a removable, patented, ultra-high efficiency cartridge.
What is an “Oil Refinery” Bypass Filter?
The “Oil Refinery” designs are Gravity-Feed devices. Some manufacturers add one or two components to their filter media and label the multi-function devices as “oil refineries.” Marketing a bypass device as an “oil refinery” overstates the device’s abilities, as one can see by examining the process in an actual oil re-refinery facility.
How does an Actual Oil Refinery Facility Operate?
An oil re-refinery plant is a large processing facility. Re-refining oil is a sophisticated process involving chemical pre-treatment, dehydration, vacuum distillation, hydro treating, fractionation, and hydro finishing. This process creates the lubricating “base oil”, which makes up approximately 80% of the lubricating oil. Next, the re-refined base oil must receive the other 20%, which consists of a mixture of chemical additives designed for the various oil specifications. These additives can not simply be poured into the base oil. Another process, called a blender operation, is required to produce the final product of re-refined lubrication oil.
What Add-On Features do “Oil Refineries” Provide?
These devices usually add a heating element and a chemical pack. The three components in the “oil refinery” are: (a) a canister portion with a filter element. This can provide adequate filtration, depending on the specific characteristics of the media used, which varies from one manufacturer to another, (b) an add-on heating device. A separate electrical connection is required to provide electrical power to the device, and (c) an add-on chemical pack, which adds chemicals to the oil as the oil circulates.
Why do “Oil Refineries” Heat the Oil?
The purpose of heating the oil is to flash off water vapor . This feature provides limited value. The moisture in cold engine oil quickly evaporates when the engine reaches operating temperature, vaporizing the moisture, allowing it to be vented from the engine. After the engine warms up, lubricating oil even is briefly exposed to temperatures in excess of 300F degrees when it circulates around the combustion areas.
Can Adding Heat Harm the Lubricating Oil?
Yes. High lubrication oil temperature causes oxidation, which degrades the oil. When the engine temperature is raised by 10 degree C, the rate of oxidation approximately doubles. Due to the negative effects of high oil temperature, engine manufactures seek to reduce oil temperature, not to raise it. Most heavy-duty equipment and performance automobiles use oil coolers to cool the oil. It is important to make sure that the oil refinery heating element is not adding heat to the oil when the engine reaches operating temperature.
What Precautions are Needed Before Adding Chemicals to Lubricating Oils?
Oil sampling and testing are required to determine the characteristics and condition of engine oil before pouring any chemicals into the oil. There are many different types of lubrication oil, each with its own complex additive formulations. Adding the wrong chemicals may cause a serious negative reaction, such as creating non-conforming viscosity, chemical degradation and the destabilization of the lubrication oil. It is important to determine if the chemicals added by the various “oil refinery” devices are compatible with the fleet’s engine oil.
What Type of Supplemental Filter is Easiest to Install?
The compact canister-type designs, such as ECO MicroFilters are easiest to install. Large canister designs are heavy, and do not fit within many engine compartment, such as in the popular diesel work trucks. Also, the large canisters often require a gallon or more of make-up oil each time the large, rolled paper towel-like cartridges are changed.
The canister designs are easier to install. Both the oil refinery and the centrifuge must be installed vertically. In both designs, the oil flows back to the engine by gravity. This means that the centrifuges and oil refineries must be installed above the height of the engine’s oil return port. It sometimes is not possible to find a location in a cramped engine compartment. Canisters, on the other hand, have pressure oil returns and can be installed below the return port. ECO MicroFilters can be installed either vertically or horizontally, above or below the return port because the oil returns under pressure, not by the draw of gravity.
Many centrifuge designs require a vacuum pressure connection. Oil refineries require an electrical connection. Among the devices on the market, the ECO MicroFilters compact canisters (various sizes depending on the size of the engine) are the easiest to install.
What is the Ideal Microfilter Cartridge?
The ideal cartridge must have three essential characteristics: (1) High Beta Ratios at the target micron sizes, such as the CLP range (1-10 microns), (2) High retention, the ability to hold a large amount of contaminants, and (3) High structural integrity to prevent media distortion, such as caking, surface build-up, or particles circumventing the filtering media, such as channeling and rupturing.
Is Filter Retention a Serious Problem?
Yes. Some cartridges claim high Beta Ratios but can not deliver high retention. As a result, they operate at reduced flow rates under real-world conditions and will not deliver the specified efficiency over the full oil drain interval.
What Factors Effect Structural Integrity?
The microfilter operates with oil flowing though it at a temperature of 180F degrees or higher, and an operating pressure of 55 PSI and higher when the engine accelerates. In addition, vehicles are subjected to bumps and jolts, which can jar the filtering media, causing channeling and rupturing. The ECO MicroFilters cartridge uses a wound cord design, which has more structural integrity than pressed cotton or rolled paper designs.
What is Filter Caking?
Filter caking is the build-up of contaminates around the surface of the media. One challenge in filter design is with high efficiency media will provide efficient cleaning but it also will clog more quickly due to caking around the circumference. If the media is a fine 4-micron media, then particulates will build up around the exterior surface, which will quickly choke off the flow of oil. This causes a short filter life. Using a 15-micron media will provide longer life but reduce cleaning of the smaller particles. In addition, under real-world conditions, cartridges prone to filter caking frequently have other structural weaknesses, which allow the particles to re-contaminate the oil. When a bus or a truck hits a pothole or other sudden jolting event, the cartridge is jolted. When jolted, often the contaminants caked around the circumference of the cartridge are dislodged. If the cartridge is also subject to channeling or rupturing, then the oil will be re-contaminated.
What is Channeling?
Channeling occurs when the oil entering the device creates a path through the cartridge back to the oil return, avoiding going through the filter media. When channeling occurs, filter capacity drops dramatically because most of the oil is not being filtered at all. It is simply starting at the surface, following a stream down to the return port on the device and returning to the engine unfiltered. Cartridge designs most prone to channeling are the compressed media designs.
What is Rupturing?
“Rupturing” is one of the most serious challenges. Rupturing occurs when the filter media collapses or the media tears. This can occur when the media design lacks structural strength, sufficient to withstand not only the 45-PSI usual operating pressure but also the high start-up pressure that can exceed 80 PSI. A ruptured media is broken open and does not provide filtration.
ECO MicroFilters cartridges prevent channeling and rupturing with an overlapping, criss-cross winding pattern, which prevents the formation of open spaces that allow channeling. The oil cannot avoid passing through the media. The winding design also prevents rupturing by providing greater structural integrity to the media.
How often is the ECO MicroFilters Cartridge Changed?
ECO MicroFilters are changed at the oil drain interval. For some fleets, the normal oil interval is based upon the number of hours of engine operation, for example, 150 hours of engine operation. In other fleets the oil drain interval is based on mileage, for example, 6,000 miles.
At the vehicle first oil drain interval after an oil change (for example, 150 hours or 6,000 miles), only the ECO MicroFilters cartridge is changed. At the second interval, (300 hours or 12,000 miles), a full oil change is performed. Using this process will reduce the number of oil changes. If currently there are ten oil changes per year, the number of oil changes will be reduces to five.
Why is Oil Analysis Important?
To assure oil quality, ECO MicroFilters recommends regular oil sampling and analysis. Regular oil sampling assures a scientific, condition-based oil change program. Based upon oil analysis, the oil should be changed if anything abnormal is indicated, such as coolant contaminating the oil. On the other hand, if the oil remains viable, the oil drain interval can be extended. Some garages now are equipped with oil analysis machines to provide quick feed-back.
What Type of Microfilter is Easiest to Maintain?
Canister-type designs are the easiest to maintain. ECO MicroFilters products only require unscrewing the cartridge and installing a new cartridge. The used high efficiency cartridge can be crushed in the fleet’s filter crusher, which squeezes out the used oil and creates a smaller form factor. The used cartridges can be disposed of in the same way as a full-flow filter.
Will Using ECO MicroFilters Void My Warranty?
No. Installing a microfilter does not void the warranty.
Will ECO MicroFilters Work in Most Engines?
Yes. ECO MicroFilters provides devices to fit virtually any engine, from a small automobile engine to a large commercial diesel. Our products are used in transit buses, cement mixers, construction equipment, police cars, commercial boats, small and large electrical generators, and ambulances.