Research On Chatter Stability Of BTA Deep Hole Drilling Processing System

Chatter is a kind of dynamic instability phenomenon in the process of machining. For thepoor rigidity of BTA deep hole drilling processing system,lateral vibration, axial vibration andtorsional vibration are easy to occur, and chatter happens. Chatter will make marks on themachined surface, and greatly restricts the improvement of the machining efficiency, eveninterrupts the processing.This paper took single BTA-solid deep hole drilling system as the research object andanalyzed two kinds of cutting chatter phenomenons caused by speed feedback anddisplacement feedback in the process of metal cutting. The cutting chatter theory is applied inBTA deep-hole machining system, and established a three-dimensional dynamic chatter modelby analyzing structural characteristics and force condition of the single BTA deep hole drill.According to the model to calculate the instantaneous dynamic thickness and vibrationdisplacement in lateral, axial and torsional direction, and then calculate the instantaneouscutting force in all directions.Using numerical simulation software Matlab/Simulink to simulate the chatter model.Ploted stability lobes diagram between the spindle speed and depth of cut，and then putdifferent cutting parameters into the simulation system and analyzed the results. From thesimulation result, received the vibration displacement and dynamic cutting force of eachparameter combination. Found the rational parameters range for BTA drilling, and thenprovide a theoretical basis and a practical analysis tool for the selection and optimization ofcutting parameters.The simulations reveal that when the selected parameters is in the stable processingregion, no chatter occurs, while in the unstable region, chatter happens. The dynamicvibration displacement change with the change of cutting force.