A crack occurred at the inlet pipe of a diesel engine supercharger during its operation, accompanied by an oil leakage phenomenon. This paper conducts an in-depth study on the cracking characteristics of the supercharger inlet pipe and its root causes from multiple aspects, including fracture analysis, simulation analysis, parts production process investigation, on-site assembly confirmation, and whole-machine modal measurement. Judging from the fracture morphology, the fundamental cause of the fracture is that the assembly displacement is excessive, and the installation stress generated thereby exceeds the design limit. As a result, stress concentration occurs at the fracture, leading to fatigue fracture during long-term repeated vibrations.



