Research On Dynamics Modeling And Fault Simulation Of Gear On Virtual Prototyping Technology

Researchers have an analysis on the physical prototype gear to the fault characteristics law of conventional gear.But it takes too much time for this method and the cost is very large.And vibration signals of the physical prototype gear may generate attenuation in the transmission process.Thus the collected vibration signals can not accurately reflect the dynamics of the gear.The virtual prototype technology uses a digital method to create virtual product model and simulates the system dynamics response in the real world.By working on virtual prototyping technology to simulate common gear faults based on oil field gearbox,so it can improve the accuracy of on-site fault diagnosis.The main research contents are listed as follows:(1)Dynamics modeling method of gearbox based on virtual prototype technology.As the herringbone gear of kinetic model is difficult to mesh accurately,it builds three-dimensional solid dynamic model of herringbone gear box components intelligently assembled in Solid Works2012,and imports the model to ADAMS.The results show that solid modeling error and the gear transmission error will result in interference in the process of gear meshing and it affects the normal running of the gear.(2)Typical fault dynamics model and simulation of the single-stage gear.As the fault extent of field gearbox is difficult to determine and the changing condition affects the gear fault,the paper sets up the model of normal gear and different degree of wear gear and teeth broken gear to conduct the simulation and analysis in the normal operating mode and variable condition mode.It is concluded that fault degree of gear is proportional to the magnitude of the impact of the time domain.The variable speed has greater influence on gear fault characteristics compared with the variable load.(3)Gear system dynamics simulation and site signal analysis verification.It is difficult to locate the fault gear in site gearbox,so the paper established the gear system dynamics model of each single-stage gear fault and multiple gear faults respectively.It can be obtained that time-domain impact number and shaft frequency amplitude can locate the fault gear better.Compared the simulated signal with field signal,it is concluded that the frequency domain of two signals are similar with each other.So it is reasonable for the dynamics model validation of the gear fault.