ASTM D2896 Base Number

The first concern I have with ASTM D 2896 is a concern of laboratory safety, which I am quite concerned with and most customers are unaware of. Simply put, the safety concerns of ASTM D2896 are considerable. The reagents used for this test are basically some of the most hazardous I have ever encountered in my professional career.

Hazardous Chemicals

The titrant used in ASTM D2896 is Perchloric Acid. This is a very strong acid that is corrosive, an oxidizer and may cause organ damage over prolonged periods of exposure. As an oxidizer, it has been known to cause explosions. One of the solvents used in this test is Chlorobenzene, a chlorinated solvent that is extremely harmful to the environment. In fact, it is so harmful that it is banned in many countries around the world. Suffice it to say, the chemicals used in this test are dangerous to those who perform the test.

Perchloric Acid On February 20, 1947, a violent explosion rocked the city of Los Angeles, California resulting in the deaths of 17 people and the wrecking of 116 buildings including the complete demolition of the O’Connor Electro-Plating Works, source of the blast. From the mass of information and misinformation, which varied from the early rumors of a powerful new army explosive, prematurely set off, to the decision, almost three weeks later, of the coroner’s jury that the explosion may have resulted from the contamination of a solution of perchloric acid and acetic anhydride with “easily oxidizable materials,” perchloric acid emerged as the nation-wide object of underwriters’ investigations.

 

Right Tests, Right Fluids, Right Equipment, Right Environment

My other concerns are with providing fluid analysis results that use the right tests on the right fluids for the right equipment in the right environment. Tests and test methods could change based on all of those factors, and too many customers request ASTM D2896 to measure an oil’s base number for good, yet misguided, reasons.

Background on Base Number Testing

First, a little bit about base number and how it is measured. The results from a base number test is vitally important to you from a maintenance and reliability aspect. Alkaline elements are added to base oils to react with the weak acids formed during diesel fuel combustion. The alkaline reserve neutralizes the acids and form slightly basic degradation products that are no longer capable of reacting to the weak acids. Eventually the alkaline reserve in the lubricant is depleted to the point where the oil can no longer protect equipment from acid corrosion.

Brief History of ASTM D2896

ASTM D2896 was designed purely to determine alkalinity reserve in new lubricants. I’ll repeat that last bit, as it is the crux of the issue; new lubricants. The test uses Perchloric Acid as a titrant because it reacts quickly and reliably with the large alkalinity reserve in new lubricants. ASTM D2896 then measures the titration product to determine the strength of the alkaline reserve. This method is reliable, which is why it is still used by oil manufacturers and listed on oil spec sheet.

However, perchloric acid is too strong to use when weakly-basic degradation products are present, especially oils used in internal combustion engines. When ASTM D2896 is applied to in-service fluids, the perchloric acid reacts to every basic element available. Instead of measuring the alkaline reserve like we want, it also titrates with the degradation products. This can result in what ASTM refers to as a “falsely exaggerated” or sometimes even “falsely understated”. For these reasons, ASTM says:

“When the base number of the new oil is required as an expression of its manufactured quality, Test Method D2896 is preferred, since it is known to titrate weak bases that this test method (ASTM D4739) may or may not titrate reliably.”

 

ASTM D4739 – A New Method?

The solution required a new method for base number testing in in-service fluids. ASTM D4739 substitutes Hydrochloric Acid as the titrant rather than perchloric acid. Because hydrochloric acid is weaker than perchloric acid, it only reacts to the alkaline reserves and not the slightly-basic degradation products.

 

 

Further, ASTM D2896 can give very poor inflection points or even multiple poor inflection points on in-service lubricants, especially if they are seriously degraded. This makes giving accurate and reliable results challenging at best, and flat out wrong, at worst. To make this scenario even worse, perchloric acid will react with wear metals in the in-service fluids. This will result in more titrant being consumed, giving a higher base number results. This can result in hiding a problem that could be resolved if you knew the real value.

The ASTM methods are pretty clear on this. ASTM D2896 should be used for new lubricants and ASTM D4739 should be used for in-service applications. However, many customers request ASTM D2896 on in-service lubricants. Why is that? I believe the main driver of this is the fresh lubricant specification or certificate of analysis lists ASTM D2896 as the method for base number testing.

ASTM D4739 / ASTM D2896 Scenario

An important part of the discussion is this essential fact- not all the tests performed on a lubricants certificate of analysis are pertinent for condition monitoring of in-service lubricants. Many tests performed on fresh lubricants are designed to prove that all additives have been added to the blend as a quality control test. As a result, if you only request testing based on your certificate of analysis from the manufacturer, you are not getting the right data to make an accurate and reliable maintenance recommendation. Best case scenario, you are paying for testing that gives you no or limited information on the maintenance and reliability of your equipment. Worst case scenario, you could be getting misleading results. This is particularly the case in the ASTM D4739 / ASTM D2896 scenario.

Change to ASTM D4739

As a result, ASTM D4739 is definitely the method of choice for in-service fluids. Do yourself a favor, make the change today and improve the quality of the information you can use to improve your reliability.

Proven Impact. Proven Uptime. Proven Savings.
Let us prove it to you.

Published July 7, 2020

In today’s shipping environment, uptime, safety, equipment life extension and increasing oil drain intervals are, and should be, the focus of any fluids analysis program.

Realizing the most value from your programs, whether lubricants, coolants, fuels, grease or filter debris analysis can help avoid:

• Unscheduled down time and unplanned maintenance and associated costs for repair
• Urgent requirements for lubricant replenishment inventory on short notice or in remote areas
• Extra lubricants expense incurred by changing the oil unnecessarily without the benefit of a historical analysis report
• Undetected problems manifesting into eventual catastrophic equipment failure

Oil analysis has been around since the 1940’s but, has matured significantly since then. Equipment has also evolved as design or environmental pressures have placed requirements for some equipment to be lighter in weight, be more fuel efficient and be manufactured to higher tolerances with more exotic materials. The result often places more stress to the lubricant, often with a lower volumes of lubricant in circulation to save weight.

Standard Practices

Take for example, marine or power plant engines with anti-polishing rings in the cylinder liners. The use of anti-polishing rings result is lower oil consumption which is an advantage for the equipment owner, but already places higher duty on the lubricant due smaller oil sump volumes and less need for frequent oil top ups. Monitoring critical parameters such as base number with laboratory and onboard testing has worked well and is already proven to be an industry standard practice.

Seeing An ROI

The benefits of your fluids analysis program can very easily pay for itself by being able to more closely monitor equipment and fluid condition, help manage implementation of oil drain interval programs, and in all cases provides information on oil and machinery condition necessary to make informed decisions about operational reliability and future maintenance.

With management reporting tools, a fluids analysis program can bring all of this information onto one platform, making interrogation of key performance indicators across assets much easier to visualize. Used properly, outliers can be detected more quickly. Of course, oil analysis is only one part of a complete maintenance program and should be used in conjunction with vibration, acoustics and thermography where applicable.

Free webinar on Fluid Analysis in the Marine Industry

If you’re interested in learning about fluid analysis as it relates to the maritime industry, I encourage you to attend our upcoming webinar on June 16. There is no cost to join and open to everyone!

Sink or Swim: How Fluid Analysis Saves Marine Engines

June 16 at 11 a.m. ET

See what will be covered and register here.

To learn more about POLARIS Laboratories® please contact us. We will show you the POLARIS Laboratories® way of helping you build a custom fluids analysis program with all the benefits of linking to your CMMS program, providing you with actionable fluids analysis commentary, and an online reporting portal, all with the benefits of being an independent laboratory and helping you save money.

 

Proven Impact. Proven Uptime. Proven Savings.
Let us prove it to you.

Published March 25, 2020

The average asset manager runs an average of approximately 10,000 hours on the asset before it’s sold. So, you’ve had your asset for a while, but it has come time to sell it. Yet, you wonder how much life is left on that asset? If you keep it for another 10,000 hours, you can save a lot of money in replacement costs and maintenance. Your asset has run well, you know its maintenance history and you ask yourself do I really need to sell it?

Deciding whether to repair or sell

Many fleets run equipment to about 80 percent of their life expectancy then sell off. But, did you know you can incorporate filter debris analysis to determine equipment reliability at that 80 percent life expectancy? If an issue is found, you can proceed with a rebuild/repair or they can sell. Things to consider when making the decision to sell:

• Did you buy your asset used?
• How was your asset’s maintenance history prior to you buying it?

Utilizing filter debris analysis

You can utilize filter debris analysis (FDA) to determine how your asset is and how it’s holding up. Here are a couple of recommendations how to incorporate FDA into your program, depending on the estimated life expectancy:

0-20%	You could characterize this as break in or, in the case of used equipment, the baseline of your equipment. What is the wear pattern in the first 20% of your usage of the asset? Submitting three filters with oil samples on regular intervals can give you a pattern.
20-80%	Recommended to test only when wear metal trends are increasing, or you see a significant jump in wear metals
80%>	This is what is referred to a senior asset. Submitting three filters with oil samples on regular intervals can give you a pattern. Then review to determine retesting interval based on results of the FDA results. You may find you need to sell your asset before significant maintenance will occur, or you may find your asset has plenty of life on it.

See what’s being caught in your filter

FDA is a great tool to add to your asset reliability toolbox. It compliments fluid analysis testing by seeing not just the data circulating in the oil, but what is being caught in the filter. This data is crucial to understanding the reliability of your equipment.

See how one company was able to to save more than $250,000 by performing the testing and avoiding gearbox replacements.

Is filter debris analysis something you want to start performing on your asset? Contact your account manager or custserv@eoilreports.com to add it to your program.

Proven Impact. Proven Uptime. Proven Savings.
Let us prove it to you.

Published March 18, 2020