The effects of picks arrangement on loads law of rock cutting with longitudinal cutting head

In order to research the effects of picks arrangement on loads pattern of rock cutting with longitudinal cutting head,loads of three kinds of cutting heads with different pick-arranged were simulated on basis of the mathematical model of rock cutting loads of cutting head,load fluctuation curves and related statistical data were developed.They indicated that the load fluctuates on two frequencies,in which the low-frequency fluctuation is determined by number of helixes and their wrap angle,the value of low-frequency is equal to number of helixes multiplied by rotating frequency of cutting head.On the other hand,the high-frequency fluctuation results from discontinuity of picks,taking the rotating frequency of cutting head as the fundamental frequency.The value of high-frequency is related to circular interval angle of picks.Under the same conditions,average and maximum of Ra,Rb,Rc,Mc increase with θi increase,but mean square deviation and volatility factor of Ra,Rb,Rc,Mc decrease.A theoretical computational formula,which can be used to guide the design of longitudinal cutting head,is developed according to the simulated data.