Study On The Load Characteristics Of Vibrating Cutting Coal Rock Under The Inclinde Attitude Of Disc Cutter

In order to improve the efficient cutting coal and rock ability of the cantilever roadheader and the working ability under complex working conditions,and improve the cutting performance of the disc cutter cutting mechanism,this paper studies the load characteristics of the disc cutter inclined attitude vibration cutting coal and rock from three aspects of theory,numerical simulation and experiment.Based on the dense kernel theory and Mohr-Coulomb strength criterion,the mechanical process and mechanism of the tooth edge and wedge surface of the disc cutter breaking coal rock are analyzed.By introducing the damage variable of coal rock and using the vector superposition principle,the radial load mechanical model of the disc cutter cutting coal rock with downward inclined attitude vibration is established.Taking the wedge angle,inclination angle,cutting thickness,feed speed and vibration frequency of the disc cutter as variables,the numerical simulation of the vibration cutting of coal and rock by the disc cutter is carried out.The load spectrum and stress obtained are comprehensively analyzed.When the disc cutter with different wedge angles has an inclined attitude,the load characteristics of the vibration cutting coal and rock,and the influence of cutting thickness,feed speed and vibration frequency parameters on the load of the disc cutter vibration cutting coal and rock are revealed.The quadratic orthogonal regression numerical simulation scheme is designed.Taking the mean value of radial load peak,axial load fluctuation and total load peak as evaluation indexes,the regression models of wedge angle,downdip angle,vibration frequency and feed speed parameters of disc cutter and each evaluation index are established.The influence law and primary and secondary order of multiple parameters on the vibration cutting coal and rock load of disc cutter are obtained.The CRITIC-TOPSIS performance evaluation model is used to evaluate the numerical simulation results.The vibration cutting coal-rock test was carried out by using the disc cutter vibration cutting test system.The load spectrum and coal-rock caving state of the disc cutter with different wedge angles in the downward inclined attitude were obtained.The load spectrum of the disc cutter vibration cutting coal-rock with cutting thickness,feed speed and vibration frequency as variables was obtained.The numerical value,standard deviation,amplitude-frequency characteristics,energy ratio of frequency-containing components and coal-rock caving state of the load spectrum were analyzed.The cutting performance of the disc cutter with different wedge angles in the downward inclined attitude was obtained.The influence of cutting thickness,feed speed and vibration frequency parameters on the load of disc cutter vibration cutting coal and rock is studied.The results of mechanical model,numerical simulation and regression model are consistent with the test,which proves the accuracy of the obtained law and verifies the rationality of the mechanical model,numerical simulation and regression model.Through the comprehensive analysis of theory,numerical simulation and experiment,the load characteristics of the disc cutter ’s inclined attitude vibration cutting coal rock are obtained,and the inclined angle with better cutting coal rock performance is determined.This study lays a theoretical foundation for improving the performance of the disc cutter cutting mechanism.