Website update in progress! You might be logged out of your account. If this occurs, please log back in.

Website update in progress! You might be logged out of your account. If this occurs, please log back in.

Sign Up

Please use your business email address if applicable

Measuring Varnish Potential

1) How did Analysts Inc develop this new method for detecting varnish potential?

QSA combines a number of varying approaches to determine the sludge and varnish potential of lubricants. Led by Brian Thompson from our Louisville, Kentucky laboratory, Analysts has independently researched this problem for a number of years. Over time we identified other organizations including oil companies, filtration companies and many end users that were also concerned about the problems of varnish build-up and the inability to identify its presence with traditional laboratory testing. These companies, including Clarus Technologies, Shell Oil, ChevronTexaco, Kleentek, and a number of plastics manufacturers and power producers were very helpful in our developmental work on QSA.

2) What makes this testing different?

QSA testing protocol was purposely designed to isolate, identify and measure the specific degradation by-products responsible for the formation of sludge and varnish, there is no other commercial technology like QSA offered in the marketplace. QSA does not use traditional oil analysis methods or instruments. Through field research, we developed the Varnish Potential Rating (VPR), in which severity levels are application specific. Until QSA was developed, there never was a VPR.

3) Why is it so difficult to detect varnish potential with traditional fluid analysis techniques?

This will get a little technical, so bear with me.

Let's start with a brief explanation of what varnish is made of and how it forms. Varnish deposits are made up of lubricant degradation by-products. Lubricant degradation occurs from oxidative, thermal or chemical attack on the building blocks of the lubricant; the hydrocarbon molecule. Hydrocarbon degradation is a complex process where normal oil molecules transform into a wide variety of harmful intermediaries. These intermediaries are highly reactive and easily transform into new compounds. As these reactions continue or propagate, new polymers of increasing molecular weight form. Many of these compounds or by-products are insoluble. Simply put, varnish is composed of these organic polymers.

Conventional laboratory test methods are not intended to identify these by-products. What conventional oil analysis does do is identify the end result of certain physical properties, contamination and component wear.

QSA focuses specifically on the chemical and physical signatures of the particular types of degradation by-products that have a high tendency to deposit on surfaces.

QSA, is concerned with elements in transition, degradation by-products that are on the way to becoming something else, varnish. Finding those elements in the oil is a complex and difficult task. One way to look at it is this is a natural evolution of the science of lubrication analysis and we are the laboratory at the leading edge of the research.

4) Does QSA replace the traditional used oil analysis programs?

No, not at all. QSA combined with a solid oil analysis program will broaden the spectrum of information that the users can utilize to make the most informed decisions from their analytical test programs. QSA focuses on lubricant properties that traditional oil analysis testing methodologies do not. QSA addresses sludge and varnish build-up. Proper routine oil analysis addresses component wear, sources of contamination and changes in the physical properties of the lubricant. Both are important players in the fight for increased equipment reliability.

5) How is the information reported?

Each client receives a customized report that includes the VPR, a severity scale that depicts where the result lies between normal and critical, a digital image of the separated contaminants, and a written interpretation of the laboratory results.

For a first time sampler, the easy-to-understand severity scale allows the user to quickly determine their risk for developing varnish related problems. We also include a historical graph of the VPR to assist in trending.

Sample QSA Report

Sample QSA Report

6) How was varnish detected prior to this technology?

Prior to the development of QSA, there was virtually no mechanism to provide an early warning of an impending varnish problem. Historically, the most common way of detecting varnish was by visual observation of easily viewed surfaces in the system. Unfortunately, dirty sight glasses and "bathtub rings" in lubricant reservoirs often do not show up until the contamination level has reached critical stage. All too often, unexpected varnish deposits were observed on internal components such as valves, bearings and gears during unscheduled and costly shutdowns or failures.

7) What kind of impact does this test have on overall plant and machinery reliability?

By monitoring those contaminants responsible for sludge and varnish, maintenance planners can properly schedule service and/or implement appropriate corrective actions before costly damage occurs and unnecessary downtime is experienced. QSA will develop into a useful tool in root cause analysis. By controlling factors that influence or promote lubricant degradation, machine reliability and availability increases. This has a significant impact on industry.

8) Do you find you have to educate potential customers as to how and why they might benefit from detecting varnish potential?

Not really. Varnish is a widespread problem that challenges many industries. We have found that almost everyone involved in maintenance, production, and reliability encounter some degree of problems associated with varnish. Most already understand the benefits of early detection.

Some of the most common problems related to sludge and varnish build-up that these professionals face are sticking servo control valves, elevated operating temperatures, accelerated wear and filter plugging. We have found that the marketplace is hungry for an effective predictive tool that can be used to monitor the otherwise missed varnish precursors in used lubricants.

9) What are your future plans and goals for this new test?

We officially introduced QSA to the marketplace at IMC 2004. Our immediate goal is to have our sales department actively introduce the technology directly to the industrial sector. Additionally our co-workers have written papers to present this technology at additional forums including the upcoming annual STLE meeting and other industry related conferences.

While the existing technology is solid and provides tremendous returns for our customers, we are continuing our research, particularly in areas such as contaminants versus lubricant performance.

10) What is the best success story you can share about detecting varnish potential?

QSA is now used extensively in the power generation and industrial hydraulic market.

We have identified dangerous fluid conditions at numerous facilities during the past year. These alerts have allowed our clients to implement appropriate corrective actions and investigate root cause before an unscheduled shutdown or worse.

One specific case involved a base load power plant. Our laboratory identified a very high VPR. Based on the QSA results, the plant initiated a corrective action utilizing electrostatic filtration as well as continued sampling. Over the course of the next few months QSA showed a gradual decrease in the VPR. When the plant shut down for planned maintenance they found the valves and filters were clean with no varnish related problems. The savings were in the tens of thousands of dollars.

11) Where can people go to learn more?

To learn more about QSA and its benefits people can visit our website at where we have excellent information on the technology. From the website they can also request additional information about our services or to have a representative contact them.

To learn more about sludge and varnish and their effects on machinery there are a number of very well written educational papers that have been published. An internet search, or call to Analysts at 800-655-4473 will get them details on this area.

Editors Note: Research does not always near fruit as meaningful as QSA. Investing in uncertain outcomes requires leadership and the ability to absorb risk. Companies like Analysts Inc., should be congratulated for taking that risk and bringing new tools to support reliability rather than being satisfied with business as usual. It was exciting to being somewhat plugged in as Mr. Thompson and others worked to bring this technology to the world last December at IMC-2004 and will also be reporting an exciting case study at LubricationWorld, December 6-9, 2005 in Tampa Florida.

Terrence O'Hanlon

Terrence O’Hanlon, CMRP, and CEO  of® and Publisher for Uptime® Magazine, is an asset management leader, specializing in reliability and operational excellence. He is a popular keynote presenter and is the coauthor of the book, 10 Rights of Asset Management: Achieve Reliability, Asset Performance and Operational Excellence.

ChatGPT with
Find Your Answers Fast