船用二冲程柴油机机身侧面振动信号的特征分析

Features of Vibration Signals on Cylinder Block of Two-stroke Marine Diesel Engine

首先,通过对船用二冲程6缸低速柴油主机机身侧面进行静态敲击试验,分析其振动信号的传播特性,证实了相邻各缸机身测点之间的振动影响较小。然后,通过对柴油机运行状态下的振动测试,分析柴油机机身侧面振动信号的时域波形特征,发现柴油机机身侧面在1个工作周期内有6个振动信号,分别对应于各缸十字头轴承滑块横向撞击导板的位置。分析结果证实,利用柴油机机身侧面的振动信号,可以监测十字头轴承的磨损状态,为进行二冲程柴油机十字头轴承的故障诊断提供了依据。

The propagation characteristic of vibration signals on the cylinder block of a two-stroke and six-cylinder marine diesel engine was investigated by static striking on engine surface,with which the influence amongst the neighboring cylinder points on the engine block was verified to be small.This provides a basis for the feasibility of monitoring each cylinder block vibration.A vibration test was conducted on the engine and it was discovered that there were six vibratory shocks in the vibration signal of each cylinder within one working cycle,corresponding to the transverse crosshead bearing impact to the guiding plate of each cylinder.The vibration signal on the cylinder block of diesel engine was proven to be useful to monitor the worn condition of crosshead bearing.These results provide a basis for the development of condition monitoring and fault diagnosis of the crosshead bearings of two-stroke marine diesel engines on board.