Engine Wear Monitoring with OLVF

Abstract

In this article, an on-line visual ferrograph (OLVF) was used to monitor the wear condition of a vehicle engine during a bench test. A quantitative index of particle coverage area (IPCA) and wear debris ferro-image were obtained via OLVF to characterize wear degrees. On-line ferrograph analysis indicated some problems with the engine from about the 17th hour. A linear threshold value method to identify running condition of engines with the OLVF data was proposed. The OLVF data were in a fault zone after running for 25 h, when a base bolt broke and the engine stopped working during the test. The engine was disassembled and inspected after the test. Several wear scars were found on the cylinder walls as well as on the bearing surfaces. The oil was added at the 26th and 55th hours, which was also reflected by the variation of IPCA. Moreover, several off-line analyses were carried out in parallel. Off-line ferrograph data did not give any information about the abnormality and only showed stable wear debris content. Spectrometric oil analysis showed that there was no significant change in contents of metal elements.

KEY WORDS:

• Wear
• Ferrography
• Equipment Monitoring
• Gasoline Engines

Acknowledgements

This work was partly supported by the National High Technology Research and Development Program of China (Grant No. 2006AA04Z431) and the National Science Foundation of China (Grant No. 50935004).

The authors acknowledge Professor Min Xu and Jingwei Ma at Shanghai Jiaotong University for providing the engine test platform, help with OLVF installation, materials about engine information, and lubricant samples.

We thank Zhinan Zhang and Ping Wang at Shanghai Jiaotong University and Professor Guangneng Dong and Dr. Tonghai Wu at Xi'an Jiaotong University for their help in performing experiments and writing this article.

Review led by Gary Barber