Oil analysis
From Wikipedia, the free encyclopedia
Oil analysis (OA) is the sampling and laboratory analysis of a lubricant's properties, suspended contaminants, and anti-wear additives. OA is performed during routine preventive maintenance to provide meaningful and accurate information on lubricant and machine condition. By monitoring oil analysis sample results over the life of a particular machine, trends can be established which can help eliminate costly repairs. The study of wear in an engine is called tribology. Tribologists often perform or interpret oil analysis.
OA can be divided into four categories:
- analysis of oil properties,
- analysis of contaminants,
- analysis of wear elements from machinery, and
- analysis of the additive package used in most motor oils
OA was first used after World War II by the US railroad industry to monitor the health of locomotives. In 1946 the Denver and Rio Grande Railroad's research laboratory successfully detected diesel engine problems through wear metal analysis of used oils. A key factor in their success was the development of the spectrograph, an instrument which replaced several wet chemical methods for detecting and measuring individual chemical elements such as iron or copper. This practice was soon accepted and used extensively throughout the railroad industry.
By 1955 OA had matured to the point that the United States Naval Bureau of Weapons began a major research program to adopt wear metal analysis for use in aircraft component failure prediction. These studies formed the basis for a Joint Oil Analysis Program (JOAP) involving all branches of the U.S. Armed Forces. The JOAP results proved conclusively that increases in component wear could be confirmed by detecting corresponding increases in the wear metal content of the lubricating oil. In 1958 Pacific Intermountain Express (P.I.E.) was the first trucking company to set up an in-house used oil analysis laboratory to control vehicle maintenance costs. In 1960 the first independent commercial oil analysis laboratory was started by Edward Forgeron in Oakland, CA.
Modern usage of OA includes the analysis of the additives in oils to determine if an extended drain interval may be used. Maintenance costs can be reduced if OA can determine if additives in the original oil are still present. By comparing the OA results of new and used oil, a tribologist can determine when an oil must be replaced. Careful analysis might even allow the oil to be "sweetened" to its original level of additives by either adding fresh oil or adding the pure additive that was depleted.
