Research On Fault Identification And Monitoring System Of Rotary Kiln Cylinder Based On Parameter Optimization VMD

Rotary kiln is the core equipment of cement industry,mainly composed of cylinder,supporting wheel,wheel and transmission parts.Affected by the harsh operating environment such as high temperature and heavy load,the kiln cylinder near the supporting roller will have thermal bending and centerline offset failure.In severe cases,the roller bearing bush will be overheated and burned,which is an important reason for the safe operation of the rotary kiln.At present,the domestic maintenance method of rotary kiln still stays in the stage of after-the-fact inspection and periodic inspection,and it is impossible to obtain the information of potential early failure of the rotary kiln in real time.Therefore,it is of great significance to carry out early fault identification and condition monitoring and evaluation of rotary kiln to reduce the risk of major accidents in kiln,reduce the economic losses of enterprises and ensure the production benefits of enterprises.This is also an inevitable trend in the development of automated and intelligent equipment.In this paper,the cylinder failure is taken as the research object,and the research on its characteristic signal extraction and fault identification is carried out,and the design of kiln monitoring system is carried out.The specific research work is as follows:(1)The stress of the roller bearing under the influence of the main failure of the cylinder is analyzed,which indicates that the bearing part is the main performance area of the cylinder failure.The dynamics modeling of the cylinder and the roller system is completed by simplifying the components of the rotary kiln.According to the actual measurement parameters and related data,the numerical simulation is carried out,and the displacement variation law of the supporting wheel under the influence of the thermal bending and centerline offset of the cylinder is analyzed.Compared with the actual working conditions,the results show that the peak,peak-to-peak and average energy of the displacement signal waveform of the roller are positively correlated with the failure degree of the cylinder,which provides a theoretical basis for the main fault identification of the cylinder and the monitoring of the rotary kiln state.(2)The VMD method is proposed to extract the fault characteristic signal according to the problem that the early fault characteristic signal is weak and easily submerged in environmental noise.Through the analysis of the simulation signal and the actual signal processing results,it is proved that the VMD method has good decomposition effect and feasibility.It is proposed to use the energy difference parameter to determine the modal quantity parameter and the orthogonality index to select the second penalty term since the main parameter selection method of VMD method is not clear.Through the simulation and actual measurement signal decomposition verification,it shows that the parameter optimization VMD method has good feasibility.Finally,the fault identification method of characteristic frequency signal is proposed which is proved to have good accuracy,so as to establish the state recognition process of rotary kiln.(3)Starting from the functional requirements of the system,the overall design of the system and the construction of the framework were carried out.According to the different functions of the module,the system hardware is selected,and the development platform is selected to complete the design of the system software.The main functions of the system are tested in the laboratory environment.The results show that the system can accurately and effectively identify the fault condition of the cylinder and verify the feasibility of the monitoring software.