Fault feature and diagnostic method of bending micro- deformation of crankshaft of piston engine

ABSTRACT

The crankshaft is the core component of a piston engine. Once a bending deformation fault occurs in the crankshaft, it can cause serious damage to the safe operation of the entire engine. However, diagnostic methods for detecting this fault are rare. In this paper, the influence of a bending micro-deformation of the crankshaft (BMDC) on the gear transmission system (GTS) was studied through theoretical analysis and simulation calculation. A fault diagnosis method for the BMDC based on the axial force of the crankshaft and the radial displacement of the flywheel gear (RDFG) was proposed. A three-dimensional model of the GTS of a diesel engine was established. The impact of the BMDC on the gear train and the fluctuation of the RDFG were calculated through a multi-body dynamics simulation. Finally, a condition monitoring and fault diagnosis system (CMFDS) was built to monitor the engine, and the effectiveness of the proposed method was verified by fault instances.

KEYWORDS:

• Piston engine
• crankshaft
• bending micro-deformation
• mechanical analysis
• fault diagnosis

Acknowledgements

The authors are also grateful for the support provided by 92942 troops of the PLA and Henan Diesel Engine Industry Co. Ltd.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the National Key Research and Development Plan [2016YFF0203305]; The Fundamental Research Funds for the Central Universities [JD1912 and ZY1940]; and Double First-rate Construction Special Funds [ZD1601].