The two main causes of crankshaft journal wear in
diesel generators are poor lubrication and uneven stress.
Firstly, poor lubrication is one of the main causes of crankshaft journal wear. Too little engine oil or the presence of hard abrasives in the engine oil, acidic substances produced by engine oil deterioration, poor lubricating oil quality, and excessive or insufficient clearance between the main journal and the main bearing shell can all lead to difficulty in forming an oil film, resulting in dry friction and accelerating the wear of the journal. In addition, insufficient lubrication, thin engine oil, and blocked oil circuits can also cause burns and wear on the surface of the shaft neck.
Secondly, uneven force distribution is also an important cause of crankshaft journal wear. When the engine is working, the connecting rod journal is subjected to periodic changes in gas pressure and inertial forces. The combined force of these forces acts on the inner side of the connecting rod journal, causing the greatest wear on the inner side and forming elliptical wear. In addition, bending of the connecting rod, longitudinal deviation of the cylinder liner in the cylinder block, poor assembly quality, and imbalance of the crankshaft can all cause uneven force on the journal, resulting in conical wear.
In addition to the two main reasons mentioned above, there are also other factors that can affect the wear of the crankshaft journal, such as mechanical impurities in the engine oil being biased towards the oil hole side under centrifugal force, becoming abrasives and accelerating journal wear. In addition, severe wear of the newly installed spindle may also be due to quality issues in spindle production.
