Short-term engine oil sludge test
US5000034A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 15, 1990 |
| Grant date | Mar 19, 1991 |
| Priority date | — |
| Expiry date | May 15, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N33/30
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A short-term test procedure for comparing the engine sludge performance of different engine oils to a reference oil. The test procedure involves establishing a base line by operating one or more engines on the reference oil while maintaining a substantially constant volume of the reference oil in the engines without changing the oil until a Coordinating Research Council (CRC) sludge rating within a preferred range of 8.5 to 9.0 is achieved. In like manner, a series of engine tests are performed on one or more test oils using engines substantially identical to the reference oil engines for substantially the same number of miles as the average test miles of all of the reference oil engines under substantially the same test conditions as the reference oil engines while maintaining substantially the same volume of the test oil in the engines as the reference oil without changing the test oil in the engines throughout the tests. The average overall sludge rating for each test oil is then calculated based on all of the tests on each test oil, and compared to the average overall sludge rating for the reference oil to determine relative sludge performance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.