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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.
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.
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.