Catastrophe analyses of complicated coal seam cut by shearer drum

To investigate the load variations of shearer drum during its cut on complex coal seams,a cutting experiment had been conducted based on the constructed structure form of complex coal seams.The constitutive model of the cutting load was built according to the experiment loads,and the mechanical models of the coal seams with different structures were also built.In addition,the mechanical model of the drum cutting into the coal was built according to the actual working conditions underground;and the cusp catastrophe model of the cutting process was built based on catastrophe analysis.Therefore,the stiffness conditions and the energy conditions of the drum cutting into the complex coal seam were obtained.Analysis results indicate that the resistance stiffness of the coal seams should be higher than the stiffness of the shearer haulage system,otherwise the strong vibration will be occurred,and the drum and transmission system may be damaged;the required energy of the coal broken should be not greater than the energy release rate of the drum,or else the drum will be lockout,even the cutting motor is damaged.