Tribology, oil analysis, and snake oil: a primer

Tribology is not synonymous with oil analysis. According to the Institution of Mechanical Engineers, London, England, and the Oxford Dictionary, tribology is the “science and technology of interacting surfaces in relative motion and of the practices related thereto.” When motion is relative, suddenly ideas like friction, lubrication, wear and erosion become relevant topics for discussion. Oil analysis is only a small part of the field of tribology.

According to Environmental Oil Processing Technology, Inc., Nampa, Idaho, of the 2.4 billion gallons of lube oils sold in the states each year, only 1.4 billion gallons of used oil are accounted for.

• Seven percent is recycled into lube oil
• 33 percent is burned as fuel.
• 19 percent is disposed of in some safe manner.
• 41 percent is unrecovered.

Speaking the same language

As we begin this exploration, it’s a good idea to acquire a solid grasp of the jargon. The folks at Noria Corp., Tulsa, Okla., have a dictionary and list of abbreviations covering words and concepts on oil analysis. This 32-page document is posted at http://www.noria.com/dictionary.html.

The Lubrizol Corp., Wickliffe, Ohio, offers good information about the arcana of lubricants at http://www.lubrizol.com/referencelibrary/index.htm. You can access a ready reference for lubricant and fuel performance characteristics; learn about lubrication theory and practice; and find a ready reference on grease. It’s a deep site—don’t get too lost.

Application notes

National Tribology Services, Peabody, Mass., posts its “Application Notes” at http://www.natrib.com/appnotes.htm. The notes are concise, single-subject explanations of different facets of oil analysis. Some topics covered include:

• Lubricant sampling techniques.
• Particle counting codes.
• Monitoring large electric motors.
• Setting oil analysis alarms.

The page lists 33 application notes, but only 23 are available online. The remainder must be requested from the company via e-mail. I sent a request for two, but gave up hope of ever seeing them after two weeks elapsed with no response. So much for the speed of the Web.

Laboratory work

The word “analysis” suggests some sort of testing. To be meaningful in a universal way, oil must be examined using generally accepted standard laboratory test protocols and procedures. The procedures the American Society for Testing and Materials (ASTM) publishes have come to be recognized as de facto standard test methods.

Problem is, nobody is giving them away on the Web. What you can do, however, is go to http://www.astm.org and click on “ASTM Store.” Then click on “Search for individual standards.” From there, you can pretty well steer your own way to listings that show the scope of the standards. At least, the misapplication of a given standard won’t be a possibility.

Simply knowing how and when to use a given ASTM standard is not enough. Darrin Clark, from Design Maintenance Systems Inc., North Vancouver, British Columbia, has a Web site at http://mypage.goplay.com/oiltech/. He provides a concise explanation of what goes on during the tests that are relevant to oil analysis. About 2/3 of the way down the page is a set of links to:

Spectrochemical analysis and wear metal limits.

• Viscosity testing (ASTM D-445).
• Water and glycol testing (ASTM D-1744).
• Fuel dilution and fuel soot testing (ASTM D-3524).
• Total acid number and total base number testing (ASTM D-664).
• Particle count testing.
• Wear particle analysis.

Each connects to a two- or three-page explanation of the test method, the instrumentation needed, a description of the test, its significance and an explanation of the results one can get by running the test. Although the page seems to be addressing motor oils, the test information is applicable to oil used in an industrial setting.

Don’t forget the transformers

Large electrical transformers also contain oil that degrades. Metro TX, a company in Northdene, South Africa, is highly focused on all things related to transformer oil. The company’s Web site discusses the testing of the oils in a page found at http://www.metrotx.co.za/analysis.htm. One warning: the page does not print because it uses white lettering on a darker background. If you need a hard copy, you could save it to your computer and manually alter the font color so it will print properly.

Dealing with used oil

There will come a time when there is no point in trying to revive or nurse along the oil in a gearbox or other piece of production gear. When you empty the machine, you will have a tub of oil that you won’t be able to dump down the sewer. You have two options with used oil: reclaim it or rerefine it.

Reclaiming the oil is the easier option. The reclaimer visits your plant to pick up the used oil, which you were kind enough to segregate and place in a sealed container. The reclaimer then dries and filters your lubricant, polishes up that dirty ol’ oil with an additive package so that it meets or exceeds original specifications, then brings it right back to your plant for further use in the machine that got it dirty in the first place. Rerefining the oil, on the other hand, involves processing it anew, an energy-intensive endeavor.

Rerefining

If rerefining intrigues you, D. Paul Ramsden, vice-president of Evergreen Holdings, Inc., Newport Beach, Calif., claims that rerefined oil is just as good as virgin stock and sells at parity with it. To give you an idea of what goes into the rerefining process and why it’s more capital intensive than reclaiming, he highlights a six-step proprietary oil rerefining technology at http://www.eco-web.com/editorial/02076.html.

Oil recovery with solvents

The Clean Washington Center (CWC) was charged by the State of Washington with providing business, engineering and technical assistance to manufacturers and local governments for increasing the use of recycled materials. CWC has published more reports on recycling technologies than all the states and federal government combined. You can access the organization’s 30-page report (pdf file) about used oil solvent extraction technology at http://www.cwc.org/OilPubs.htm. It describes a system for recycling 2,000 gallons of used oil per day and includes flow diagrams, P&ID, references and an equipment list.

It looks like a workable system. According to Matt Harrison of CWC, this information is in the public domain. Any of you could build an oil purification system in your spare time without having to worry about paying royalties or licensing fees. Turn it into a “dot com” and go for the IPO. But don’t quit your day job until you’ve got it lined up properly.

This Internet column features non-commercial Web resources and content that have genuine value to plant professionals. Finding value in the chaos we call the Web is sometimes difficult, so we search it so you don’t have to. But, when it comes to finding someone who will dispose of your used oil, I’m afraid you’ll be on your own. Hundreds of commercial enterprises will do that, none of which will be endorsed here. Just fire up your browser and go to any search engine. Type in some phrase, such as “oil recycling,” “waste oil” or any similar wording. You will find enough to keep you busy while the dirty ol’ waste oil continues to accumulate.