DF Sales&Marketing
Oil Tech Moderator
In part from jarrod potteiger, machinery lubrication magazine
I decided to write on this topic because I continually hear people say that oil doesn’t go bad, it just gets dirty. This implies that if you keep the oil clean, it will last forever. This is not true. I am frequently dismayed to see how many people simply don’t change the oil, [or don’t change it when they should] In certain machines [engines and other equipment].
In general, all in-service lubricants will fail at some point. That being said, there are numerous ways to manage the condition of a lubricating oil and extend its life significantly. There are three primary causes that necessitate an oil change:
1) degradation of the base oil.
2) depletion of additives
3) contamination
some of these conditions can be remedied, yet others cannot.
Base oil degradation
base oil degradation May be the most common reason for oil failure. The most common type of base oil failure is likely oxidation. When oil oxidizes, the primary by-products are acid and insoluble materials, which can lead to serious surface deposits and corrosive wear. To address this problem, most lubricants are formulated with antioxidants, but they don’t last forever.
Like many lubricant additives, oxidation inhibitors are used up as they perform their intended function. Once these additives are consumed, the base oil begins to oxidize. Many factors contribute to oxidation including heat, contaminants and base oil quality. Oil temperature plays a large role in the rate of oxidation. For every 10-degree celsius increase in oil temperature the rate of oxidation doubles.
Contaminants also cause significant changes to the rate of oxidation, acting as catalysts for the reaction or, in the case of air, providing one of the reagents. Certain wear metals can dramatically increase the rate of this reaction, especially in the presence of water.
The quality of the base oil used in the lubricant plays a role as well. Lower quality base oils tend to contain more inherently unstable constituents such as aromatics and other unsaturated hydrocarbons which more readily react with oxygen.
In addition to oxidation, base oils can fail due to thermal degradation, hydrolysis and various chemical reactions with contaminants. While mineral base oils and polyalphaolefins (paos) have good hydrolytic stability, several types of synthetics are prone to reacting with water, which forms corrosive acids.
While it May be impractical to forever prevent base oil from failing, we can dramatically impact the oil’s life by managing the influencing factors. Managing the oil’s temperature, selecting a good-quality base oil, monitoring antioxidant concentration, and preventing or removing contamination goes a long way toward extending the lubricant’s service life.
Additive depletion
although many additives such as antioxidants enhance the properties of the base oil, other additives perform functions the base oil cannot. Antiwear, extreme pressure, detergents and dispersants are examples of such additives. Even if a lubricant’s base oil is in good condition, the lubricant can no longer perform all of its duties when certain additives are depleted and, therefore, must be changed.
Additives are depleted by a number of different mechanisms. Water can react with certain additives (hydrolysis), and also can attract and remove others (water washing). Some additives are removed by particle contaminants (particle scrubbing), and others are simply used up when performing their intended functions.
Once again, these processes cannot always be eliminated, but they can be minimized. By using a well-chosen lubricant, maintaining proper oil temperature and controlling contamination, we can prevent any unnecessary additive loss, thereby extending the useful life of the lubricant.
Contamination
many types of contaminants contribute to the degradation of lubricating oils, but that’s not the worst of it. Of course, we all know that contaminants such as particles are responsible for the majority of mechanical wear in many components. Because of this, we often change oil before it fails, simply to remove the contamination.
For systems with no means of contamination removal, such as mechanical filters, this is the only way to control contaminants and ensure proper lubricating conditions. However, changing oil to remove contamination will be only partially effective, at best.
When the oil is changed, many times a significant portion of the old contaminated oil is left behind [a good example of this is when you are servicing an automatic transmission].
Extending the life of your lubricants, for the most part, is a worthwhile endeavor. If you examine the cost of changing the oil in the average machine [or engine for that matter], you might be shocked to see what you spend. The keys to achieving maximum life from lubricants are proper selection, temperature management, good oil analysis and contamination control.
Just remember to keep the oil clean, cool and dry.
Editor’s notes on this headline article……
I was really glad when I came across this article as it covered a topic which many of us in the oil industry have encountered hundreds, perhaps even thousands of times in our careers.
Mr. Potteiger certainly did an outstanding job identifying and focusing in on the various aspects of “why oil goes bad” in a very easily understood manner.
One of the facts which are mentioned several times during the article is the quality of the base oil used in the formulation of the product. This was like getting back to “lubrication 101” as it is the building block of a quality product…..base stocks can be compared with building foundations, the better the foundation, the stronger the structure will be (oil formulations are, after all, a series of molecular structures).
There are literally hundreds of different base stocks which are available and used by oil formulators for various reasons, one might be the fact of keeping costs down to be price competitive by using a less expensive, lower quality product, but you certainly cannot expect to get the best performance from oils formulated in that manner.
Another point, although, sadly not expounded upon enough is the quality and amount of additives used in the formulation. Here again, like base oils, there are hundreds, perhaps thousands of different combinations of chemicals available which oil formulators can use.
The quantity and quality of the additives used in a finished product will fortify the base stock accordingly.
Consequently, the better quality base oil stocks combined with the better quality additive packages will result in products which will perform at the utmost level of expectation.
Where are we going with this? Of course, regular readers of this publication already know that swepco brand lubricants use nothing but the finest quality mineral oil stocks in their formulations combined with the most effective state-of-the-art proprietary additive chemistry packages available.
Swepco lubricants are generally higher in price than those commonly found in the market, that’s because they do not use cheap ingredients which May compromise the quality of their products. It doesn’t matter what industry is served, from industrial plant applications to high performance racing, customers can rely on one thing….quality….. "it doesn’t come cheap, and it pays for itself many times over in the long run!"
dick floryanowich
I decided to write on this topic because I continually hear people say that oil doesn’t go bad, it just gets dirty. This implies that if you keep the oil clean, it will last forever. This is not true. I am frequently dismayed to see how many people simply don’t change the oil, [or don’t change it when they should] In certain machines [engines and other equipment].
In general, all in-service lubricants will fail at some point. That being said, there are numerous ways to manage the condition of a lubricating oil and extend its life significantly. There are three primary causes that necessitate an oil change:
1) degradation of the base oil.
2) depletion of additives
3) contamination
some of these conditions can be remedied, yet others cannot.
Base oil degradation
base oil degradation May be the most common reason for oil failure. The most common type of base oil failure is likely oxidation. When oil oxidizes, the primary by-products are acid and insoluble materials, which can lead to serious surface deposits and corrosive wear. To address this problem, most lubricants are formulated with antioxidants, but they don’t last forever.
Like many lubricant additives, oxidation inhibitors are used up as they perform their intended function. Once these additives are consumed, the base oil begins to oxidize. Many factors contribute to oxidation including heat, contaminants and base oil quality. Oil temperature plays a large role in the rate of oxidation. For every 10-degree celsius increase in oil temperature the rate of oxidation doubles.
Contaminants also cause significant changes to the rate of oxidation, acting as catalysts for the reaction or, in the case of air, providing one of the reagents. Certain wear metals can dramatically increase the rate of this reaction, especially in the presence of water.
The quality of the base oil used in the lubricant plays a role as well. Lower quality base oils tend to contain more inherently unstable constituents such as aromatics and other unsaturated hydrocarbons which more readily react with oxygen.
In addition to oxidation, base oils can fail due to thermal degradation, hydrolysis and various chemical reactions with contaminants. While mineral base oils and polyalphaolefins (paos) have good hydrolytic stability, several types of synthetics are prone to reacting with water, which forms corrosive acids.
While it May be impractical to forever prevent base oil from failing, we can dramatically impact the oil’s life by managing the influencing factors. Managing the oil’s temperature, selecting a good-quality base oil, monitoring antioxidant concentration, and preventing or removing contamination goes a long way toward extending the lubricant’s service life.
Additive depletion
although many additives such as antioxidants enhance the properties of the base oil, other additives perform functions the base oil cannot. Antiwear, extreme pressure, detergents and dispersants are examples of such additives. Even if a lubricant’s base oil is in good condition, the lubricant can no longer perform all of its duties when certain additives are depleted and, therefore, must be changed.
Additives are depleted by a number of different mechanisms. Water can react with certain additives (hydrolysis), and also can attract and remove others (water washing). Some additives are removed by particle contaminants (particle scrubbing), and others are simply used up when performing their intended functions.
Once again, these processes cannot always be eliminated, but they can be minimized. By using a well-chosen lubricant, maintaining proper oil temperature and controlling contamination, we can prevent any unnecessary additive loss, thereby extending the useful life of the lubricant.
Contamination
many types of contaminants contribute to the degradation of lubricating oils, but that’s not the worst of it. Of course, we all know that contaminants such as particles are responsible for the majority of mechanical wear in many components. Because of this, we often change oil before it fails, simply to remove the contamination.
For systems with no means of contamination removal, such as mechanical filters, this is the only way to control contaminants and ensure proper lubricating conditions. However, changing oil to remove contamination will be only partially effective, at best.
When the oil is changed, many times a significant portion of the old contaminated oil is left behind [a good example of this is when you are servicing an automatic transmission].
Extending the life of your lubricants, for the most part, is a worthwhile endeavor. If you examine the cost of changing the oil in the average machine [or engine for that matter], you might be shocked to see what you spend. The keys to achieving maximum life from lubricants are proper selection, temperature management, good oil analysis and contamination control.
Just remember to keep the oil clean, cool and dry.
Editor’s notes on this headline article……
I was really glad when I came across this article as it covered a topic which many of us in the oil industry have encountered hundreds, perhaps even thousands of times in our careers.
Mr. Potteiger certainly did an outstanding job identifying and focusing in on the various aspects of “why oil goes bad” in a very easily understood manner.
One of the facts which are mentioned several times during the article is the quality of the base oil used in the formulation of the product. This was like getting back to “lubrication 101” as it is the building block of a quality product…..base stocks can be compared with building foundations, the better the foundation, the stronger the structure will be (oil formulations are, after all, a series of molecular structures).
There are literally hundreds of different base stocks which are available and used by oil formulators for various reasons, one might be the fact of keeping costs down to be price competitive by using a less expensive, lower quality product, but you certainly cannot expect to get the best performance from oils formulated in that manner.
Another point, although, sadly not expounded upon enough is the quality and amount of additives used in the formulation. Here again, like base oils, there are hundreds, perhaps thousands of different combinations of chemicals available which oil formulators can use.
The quantity and quality of the additives used in a finished product will fortify the base stock accordingly.
Consequently, the better quality base oil stocks combined with the better quality additive packages will result in products which will perform at the utmost level of expectation.
Where are we going with this? Of course, regular readers of this publication already know that swepco brand lubricants use nothing but the finest quality mineral oil stocks in their formulations combined with the most effective state-of-the-art proprietary additive chemistry packages available.
Swepco lubricants are generally higher in price than those commonly found in the market, that’s because they do not use cheap ingredients which May compromise the quality of their products. It doesn’t matter what industry is served, from industrial plant applications to high performance racing, customers can rely on one thing….quality….. "it doesn’t come cheap, and it pays for itself many times over in the long run!"
dick floryanowich