The Excitation Sources Analysis And Vibration Research Of Large-scale Coke Pushing Devices

A coke pushing device is the core component of coking industry.Vibrational problems of coke pushing device during working could bring potential safety problems and have bothered engineers for many years.As the lack of systematic research and analysis in this domain,the vibration characteristics researching method combined with excitation source characteristics analysis and an experimental test was put forward.As a result,this paper concluded the main reason caused coke pushing device vibrated was self-exacted vibration caused by dry friction.The main research contents were summarized as follows:(1)The multiple excitation sources environment where coke pushing device existed was analyzed.Pusher resistance incentive estimation based on the different electronic current between pushing and return ways was put forward.Gear rotation frequency and gear meshing frequencies were adopted as the gear excitation characteristics.The bearing inner,outer and rolling body frequency were adopted as the bearing vibration characteristics.The changing load caused by the support structure was taken as the support structure excitation.The rigid natural frequencies were taken as the characteristic frequency of dry friction self-excitation.Characteristics of different excitation in the time domain and frequency domain were analyzed in detail.(2)Modal analysis was carried out on the coke pushing device,including 3D model establishment,unstructured grid division,modal solution,etc.Firstly,the model was simplified,and then the modal analysis was carried out for different working states.The analysis results showed that there was a strong consistency between the natural frequency and the corresponding mode of the focusing device under different working conditions.(3)Analyzed the dry friction self-excitation vibration caused by slipper,which mainly included the mathematical modeling and simulation analysis of the dry friction self-excitation vibration.The mathematical model of self-excited vibration was established and the main parameters were identified.According to that,the relationships between main parameters and how could the parameters influenced the self-excited vibration was determined.After that,the single factor control experiments were carried out for each variable in ADMAS,and the influence of each parameter on vibration was determined.(4)The acquisition,processing,and analyzing the vibration signal of the coke pushing device was completed.Using the acceleration sensor and a vibration acquisition system,the vibrational signal of the coke pushing device was collected.Combined with characteristics of coke pushing device and multiple excitation resources,the vibration signal was layered by empirical mode decomposition firstly.Then,after removing the high-frequency noise layer,the high energy layers were selected based on whether the energy of a single layer accounts for 15% of the total energy.After that,the high energy layers were superimposed to reconstruct the signal and analyzed.Based on that,the local signals with obvious vibration in X,Y,and Z dimensions were spotted and analyzed in detail.The vibrational signals analysis showed that the main vibration occurred in the second half of the forward process and the first half of the return process.The main vibration frequencies were 36 Hz,45 Hz and 62 Hz.Above that,several harmonic signals in which the intervals were 3.6 Hz occurred around main vibration.Based on the double dimension comparison analysis about vibration signals in time and frequency domain,it determined that the main reason causing vibration was friction self-excited vibration caused by dry friction.