The Oil Analysis Big Picture: Why it is Critical to Maintainers and Operations

If you are tasked with maintaining a plant’s most critical of equipment this post may have some information that you might find useful. If you are a plant manager who is concerned with saving money on repairs, extending the life of your lubricants, read on.

Trico’s New Oil Analysis Laboratory Opened in Early 2013

Trico’s New Oil Analysis Laboratory Opened in Early 2013

At some point, someone convinced you that sending an oil sample to a lab for analysis is a smart thing to do. After some discussion, you dispatched your best technician to collect the sample. The technician used the best possible sampling techniques and properly labeled the bottle. A few days later you receive the results and can clearly read the numbers and charts on the report.
Now, I ask you, what are you going to do with that sheet of numbers? What does it all mean? How are you going to convert this presumably important information into some action that justifies both the lab cost and in-house cost charged against your department? Essentially what I want to understand is WHY?

The big picture
If you remember elementary chemistry, you know that lubricants are nothing but a mixture of long-chain hydrocarbons that somebody dug out of the ground mixed together with some specialty chemicals designed to improve its properties. What is great for maintainers is that you can’t simply destroy hydrocarbon molecules by grinding them between gears and mashing them between steel plates. Hydrocarbon molecules are immune to physical attack making them perfect for lubricating industrial machinery. These molecules do break down over time and through oxidation.
Oil analysis should address the fluid contaminants.
The sump and system from which your technician drew that sample constitutes a container. There are other fluids besides oil that can reside in that same container. These fluids are the enemy of your critical equipment and are considered contamination.
Oil analysis should address the bits and pieces of solid contaminants.
The only reason a machine requires a lubricant is that somewhere in its internal workings are some pieces of metal and other materials rubbing or banging against each other. This mechanical action induces stress that exceeds the metal’s elastic limit and metal pieces break off and incorporate into the mix of lubricant and moving metal. The oil carries these pieces away so more stress can break off more pieces.
Oil analysis reports present a lot of information covering the properties of the oil, the fluid contaminants mixed in the oil and the solids suspended in the oil.
Let’s get specific on some of the terms and metrics that can have an impact on your lubricants.

Specific gravity
The specific gravity is nothing more than the mass per unit volume referenced to a standard temperature. Oil contaminated by solvents, for example, has a specific gravity different from that of clean oil. It’s a nice number to know, however it’s typically not a tell-all and may simply indicate that additional investigation is needed to see a bigger picture.

Absolute viscosity
The most important characteristic of your lubricant. Viscosity is a measure of the oil’s relative resistance to flow. Its value depends on the temperature at which viscosity is measured, the viscometer used for the measurement and the technique of the lab technician. For best results, always measure the viscosity at the same temperature on the same viscometer operated by the same technician. Since this may be impossible to do on-site, many companies outsource this measurement to insure total consistency.
Measuring viscosity at a constant room temperature yields the greatest resolution. At elevated temperatures, the difference between the viscosity of degraded oil and good oil is too close to differentiate. The correct viscosity is application dependent, temperature dependent, and has both a lower and upper limit. The specs on the lubricated machine should indicate the proper viscosity to be used. Using a lubricant that fits squarely in this range is critical to the longevity of the equipment.
Because lubricants are mixed on a per batch basis, you simply cannot count on your viscometer to give you readings shown on the label on the oil drum or on the oil spec sheet. To be sure your lubricant is in spec, measure the viscosity to get a baseline value for the current lot of clean oil. Get another baseline reading each time you start drawing from a different load of oil.
Total acid number (TAN) and Total base number(TBN)
This measurement, in milligrams of potassium hydroxide per gram of oil, is related to the level of oxidation present in the oil – more oxidation, higher acid number. Get a baseline reading on a sample of clean oil.
As the additives deplete over time, the reported acid number drops, goes through a minimum, then rises. It drops because the additives are being depleted. The curve bottoms out when they are gone. It rises again because there’s now genuine acidic material in your oil.
Acid buildup in oil is a bad thing. Chemistry being what it is, bases react with acids to neutralize them. The total base number is an aggregate measure of the concentration of components in the oil that counteract acid buildup. It’s measured in equivalent milligrams of potassium hydroxide per gram of oil.
This test is generally performed only for oils taken from internal combustion engine crankcases.
There seems to be some controversy about changing oil on the basis of total base number. Some proponents advocate changing oil when the total base number depletes to 50% of the total base number of the virgin stock. Others advocate waiting until the total base number drops to somewhere around 2 mg. KOH/g. My advice – be conservative. Oil is cheap, machinery isn’t.

Spectrographic analysis
Fourier Transform Infrared Spectroscopy (FTIR) is a versatile way to determine contamination levels and additive depletion in oil. Infrared radiation interacts with materials on a molecular level, not the atomic level.
The spectrometer measures the infrared light passing through the sample. The spectrograph is nothing more than a curve of the intensity of the transmitted IR as a function of wavelength.
This analytical method monitors the depleting concentration of antioxidants and anti-wear components. It also measures increasing levels of contamination from moisture, oxidation products and dissolved metals. If the sample is from an internal combustion engine, it also measures ethylene glycol and soot levels.
Particle counting
Particle count is a critical test in proper oil analysis that reveals the type of wear debris in the oil and its particle size distribution. Keep an eye on how the distribution curve shifts over time. If you want to gain the most value from this test, this data should be tracked regularly and trended.
Wear particle monitoring depends on the magnetic properties of the particles. Solids in oil is bad. Particle count is a direct measure of the degraded pieces of gear, bearing, and/or other metals which have disconnected from the machine and are loose in your lubricant. Since particle count isn’t the only critical factor in lubrication degradation use this as part of a comprehensive series of tests vs. a tell-all.

Analytical ferrography
Analytical ferrography is another form of wear particle analysis. This approach identifies the composition of the solid chunks in your oil sample. The objective is to identify the solid pieces seen in the microscope eyepiece. Getting meaningful results as the identity of wear particles, their sizes, counts, size distribution and shape is a matter of experience and training.
Because this test is a visual inspection, experienced technicians can identify nonmetallic and other nonmagnetic wear particles. Because analytical ferrography is a direct look at the particle, it provides more objective information about the machine from which the oil was taken. The test is neither inexpensive nor quick because there’s a great deal of handling and expertise in testing this way. Ferrography can tell you what pieces of your equipment are wearing and at what rate which makes this test best for verification testing.

So, what now?
There are more test available – for instance, the entire series of ASTM standards for measuring oil. Practical oil analysis depends on the lubricant and the application. The key to making sense of oil analysis is understanding that no single test can give an absolute clear picture.
To make your results the best they can be, you must be consistent, get a representative sample, and provide trending for each of the tests that relate to your application and equipment.

Alarming test results
From time to time your results may be so out of limit that it doesn’t make sense. Good labs will re-test when this happens to make sure it was not an error in the test equipment or process. What is highly alarming is getting this result even after the sample is re-tested. The recommendation would be first get another sample to the lab as soon as possible to have that second sample re-tested as well. If the results are identical or nearly identical you should consult with the lab to discuss what may be going on in the equipment. That expertise isn’t something that people just know, it comes from thousands of samples from similar equipment in other machines and environments. Your ferrography results don’t lie, having someone be able to explain the result in a way that makes sense is the true value of the program in the first place.

Oil analysis is critical to reducing the costs of maintaining equipment and can assist your maintainers and operations teams in knowing the “how long” before maintenance or critical equipment failure is imminent. This understanding in the practical environment is the difference between maximum uptime, and lost revenue due to downtime. Trico is an industry leader in oil analysis, existing to assist industry in extending the life of critical equipment and lubricants. Contact our team today with any questions regarding lubrication practices, analysis, or training.
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5 Critical Components of a Lubrication Management Program

Being asked to do more with less can mean a lot of things, setting up a lubrication management program is part of an overarching solution to the reliability puzzle.

Operations

Lubrication Excellence by Trico

Your Path to Lubrication Excellence

The reality is that lubrication management programs often work best when operations staff can be included into the regimes. This is for a number of reasons. Operations involvement or ODR (Operator Driven Reliability) might take the form of regular inspections which don’t need to be certified or may be cost prohibitive based on the value of their tasks. Reducing overall reactive maintenance in a plant requires all parties to take steps to work together. Operators are fantastic data reporters and can do simple inspections and log data, seeking changes which would in time occur beyond set or noticeable limits. Operations professionals are also most likely to spot trends based on the data where maintainers may be overwhelmed with daily tasks and not necessarily be able to put the pieces together as they come together. If maintainers embrace operations they win by being able to react to trending data vs. down equipment.

Where do I start?

Implementing a lubrication management program starts with a criticality assessment. This is a great way to determine which equipment in the plant is critical. Critical equipment typically means that when down production stops or is significantly impacted or safety and environmental concerns are present. This equipment assessment generally includes agreement on potential failure modes, probability, and impact. Once these assumptions are made assessment of the potential frequency and impacts of downtime are entered into the overall equation providing a picture of which pieces of equipment are most critical.
Once criticality is determined, reliability programs can be developed which focus on treating potential causes, understanding how failures can occur, and what limits in condition in the array of possibilities looks like. The priority for a maintenance task should be determined by the level of risk associated with not performing that task. The level of risk associated with not doing that task is determined by both the consequences of the potential failure that may result if the task is not performed and the likelihood of that failure occurring if the task is not performed at the particular point in time at which that priority is being determined. Oil analysis is key in any sort of reliability program in that through proper limit setting and ferrography you see what’s going on inside the equipment. Setting proper oil analysis limits is critical and a good partner will help you in terms of finding or setting limits.
Typically a risk assessment matrix can be utilized to visualize the aggregate data while predictive tasks are in progress to keep within the limits set.

What should I do with the data?

The difference between meaningful conversations and excuses is sometimes as simple as having the data or sharing the data in a timely way. I can think of several examples of ideas that have changed people’s lives and the only thing that made them happen was someone wrote them down.
Data that can be logged and stored is valuable…that is only if it can be used to understand specific things related to the equipment in question. This is where operations excels when compared to maintainers, so as maintainers start to understand the value of data in PDM. Data will first provide limits in terms of vibration, particulates/moisture/oxidation in the lubricant, and other things like heat increase over time and power consumption. The best data is that which is consistently representative and shared freely amongst all parties who have ownership in the reliability efforts.

Internal competencies

Understanding how a particular piece of equipment runs and is meant to run is only half the battle. Getting maintainers and operations staff online with best practices and how they are implemented is a critical component in qualifying in-house teams. Internal competency can assist your program by reducing costs involved in outsourcing as well as understanding limits and how those limits affect the equipment. Understanding what is about to happen in the equipment when limits are met is also a key factor, in some ways this can only happen based on experience so as your teams change over time always seek experienced maintainers and operations employees.
Outfitting the equipment
Lubrication management programs require tools of the trade. Lubricators, vibration monitoring equipment, sample ports for pulling oil samples, and other things may be required to get the equipment in the right condition to be properly maintained and monitored. I cannot be more animate when it comes to the role of oil analysis in any program or piece of equipment, set it up to pull representative samples, and be religious about doing it.

Trust the data

Many times when we start using pure data to make decisions there can be a difference in how we perceive what the data is showing us and what has actually transpired. The oil sample shows added ferrous particles, yet the temperature is actually falling slightly. Typically more metal in the oil could mean more wear which really should point to higher temperatures. We didn’t realize that the ambient temperature was falling and so by virtue of not having that data we assume it’s not. When you don’t trust the data and go on gut feel having all the data is useless and the adjustments which are required to maintain the program are missed, thus making the program fail to provide the reliability it was designed to support.

At the end of the day, your organization will have to make the criticality assessment or audit and then make a decision on how far to go with the results. Thinking in terms of “good, better, best” is a good start to make heads and tails of where your reliability program is in terms of where it should be and where your goals lie. Sometimes we look at reliability programs on a scale of 1 – 10 and we fail to put a program in place because we could only hope to reach being a 5 vs. being a 10. Not every plant needs to have a world class program to provide a bottom line boost in reliability. Sometimes being a 5 moves the needle and provides a framework for building next steps. All of the items don’t need to be done all at once either, using a graduated or hierarchical approach could also be the solution that works best for your organization. Trust me when I say that if you can document moving the needle from increases in reliability you will have all the buy-in necessary to get to the next level and beyond.
We’d love to hear about your experiences in lubrication management programs and what has or hasn’t worked. If you’d care to share your examples, contact me directly at rmccormick@tricocorp.com , lets chat.
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Plant Reliability Means Being Consistent

Plant reliability can be greatly improved with consistent activities designed to improve lubrication

Field ServicesA friend and I were discussing consistency the other day, and he gave me a unique insight into how inconsistent he’d been, and how it wasn’t until near full collapse of his department did he understand what being consistent meant for his team. His story…
Back in the 80’s and 90’s I remember being so busy that maintaining anything was difficult based on the daily fires being put out. It was hard to do anything well because each new item was more critical than the last it seemed. Reliability tasks were shunned for more urgent repair, replace, upgrade, and retrofit jobs. I remember thinking about how I’d ever get back to a place where I could actively maintain equipment vs. constantly doing these huge jobs during downtime. I liked the repair/replace jobs don’t get me wrong, it’s just that they were always so urgent and when they are unplanned the urgency goes through the roof.
Then the slow time came and half of our staff was either let go or cut back to part time. There was no money to do anything. We were asked to make things happen that seemed impossible. We ended up stopping all un-necessary upgrade work, which actually was a blessing in disguise because now we could see the light at the end of the tunnel. The problem was constant fear…fear of something critical going down. We learned that being consistent with our predictive or pro-active maintenance tasks was keeping equipment running. Why hadn’t we been consistent all the time? How much money would we have saved if we’d been able to maintain our consistent focus in the right areas, in front of the downtime?
This was in a foundry that my friend and I worked in back in the 90’s, his role was maintainer and millwright, his story isn’t unlike many I’ve heard personally.
Times have changed, improvements in processes, improvements in products…happened. Your maintenance teams who’ve been doing the same things for 30+ years can and must change to continue to meet demands.
Fast forward to 2015 and I cannot remember a time when budgets were tighter, maintainers roles in plants have never been more critical. Margins are as tight as they’ve ever been and companies manage to be able to stay afloat because their teams learned back in the “good ole days” that proper maintenance in a plant requires consistent focus on tasks and operations that revolve around keeping the plant running smoothly vs. trying to crank every last part out at any cost. Technology has helped in terms of communications and planning, but the real gains have come from the necessary lessons about keeping things on line to begin with. In essence saving money is the new profit. Raising the bottom line for business means cutting costs.
So if you’ve not found yourself in a place where consistency is the rule, the good news is that you can change that for your team. Being consistent means keeping a cadence, an executable rhythm of tasks designed to keep the place going. It starts with oil analysis, sending your samples in consistently. Oil analysis is one of the critical steps in avoiding catastrophic failure. Oil analysis is one of the few ways you can look inside your equipment and identify what is actually happening both from the lubricant side and the equipment side. Oil analysis results should direct your maintenance activities in critical assets. Using oil analysis is one way to avoid critical unplanned failures resulting in increased equipment availability and uptime. At Trico we have thousands of customers, many who pre-pay for oil analysis and send a sample once a month for a couple months, then skip a couple, then when things go critical send samples in weekly. Having the best data about your equipment in this area means being consistent and logging or tracking the data. Getting operations involved in uptime is also a key to consistency, operations guys can check and log oil levels in gearboxes/pumps, and other rotating equipment as well as log levels. Desiccants can now also be checked by operations in the same way, logging the data through time.

Opto-Matic Closed System Oiler

Opto-Matic Closed System Oiler

When you consistently keep oil levels optimal, consistently keep contamination at bay, and you understand what’s going on in your equipment you have an advantage over those who do not. Your equipment can run longer, cleaner, more efficient. In some studies in gearbox applications I’ve seen oil change frequencies drop from quarterly to yearly and in at least one case two years. Think for a minute what that could mean for your bottom line. BONUS: When your VP of operations comes down and asks what you’ve done to maximize uptime, you have a clear and concise answer that makes sense. You can probably even relate that into dollars because you know how expensive an unplanned rebuild can be. And the VP types definitely like that.
Get consistent by investing small amounts of resources (money), in oilers, desiccants, and oil analysis. Keep consistent by using these tools. You’ll find that keeping in front of downtime is much easier and the money you’ll save the company will make your team look like the professionals that you are.

Understanding the TLM or Total Lubrication Management system that Trico provides can help you be consistent in other ways by implementing plant wide processes and systems that provide the structure for consistency. Contact one of our consultants to learn more about what the TLM is and how it can make your plant maintenance as consistent as possible.

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