Research On Performance Test System Of Needle Roller Bearing For Big Rod

The performance of connecting-rod big-end bearing can directly influence the efficiency, service life and safety of motorcycle engine; therefore, it is significant to study its performance. The connecting-rod big-end bearing without inner and outer rings may axially drift in the engine and then cause vibration and noise when running at high speed.Many domestic and foreign studies have been conducted on the performance of needle roller bearing and its test system, while few have been conducted on the test of needle roller bearing without inner and outer rings, and the test equipments are mostly single functional and expensive, thus accordingly, this study focuses on three kinds of early failures of connecting-rod big-end needle roller bearing, i.e. axial drift, vibration and abnormal noise, then develops test system, and builds test platform.The test system of needle roller bearing is designed with Solidworks software and PLC programming language, and then its feasibility is verified through experimental analysis. In the testing stage, the data are collected by NI data acquisition card, signal conditioning amplifier system and PC; in the data analysis stage, the data are analyzed with Labview programming and noise and wavelet analysis module. The final results accord with the fault information, providing reference for further research of needle roller bearing. Of all the early failures of needle roller bearing, needle roller skew and needle roller jam happen more frequently, so both of them are focused on in the experiment, and the false bearings are compared with the intact one, to explore the differences in waveform and data. The final results show that when the needle roller deviates caused by poor quality of supporting frame, it will raise adjustment collision in load zone, followed by vibration and noise. When individual needles are stuck, vibration acceleration will obviously increase, coupled with significant level varying of noise; in case two needle rollers are stuck, the inertia wheel can hardly rotate.It is of theoretical and practical significance to research the test system of motorcycle engine’s connecting-rod big-end needle roller bearings, explore early common malfunctions of needle roller bearings and improve motorcycles’ safety.