Test And Simulation Of Dynamical Variables Of Mass Finishing

The surface quality of parts has very important influence on performance,reliability and life of mechanical equipment, such as the wear resistance, theaccuracy of cooperation, corrosion resistance, contact stiffness and fatigueresistance. Surface finishing technology can debur and deflash to reduce thesurface roughness, and remove the surface oxide layer, the adhering and residualslag after casting, stamping and welding to ensure the blank surface. It also canchamfer, debur and eliminate the micro-crack to improve the physical andmechanical properties. As a kind of typical free abrasive surface finishing, themass finishing is widely used because of its low processing cost, goodprocessing effect, high processing efficiency and the simple equipment.However, the study of mass finishing is stay on the qualitative analysis, thepaper does quantitative numerical analysis of the movement of abrasive, themutual effect between the abrasive and the workpiece, the dynamic quantity ofthe workpiece by using the three dimensional discrete element software EDEMand related test equipment. The main research of paper is as follows:1. The dynamical variables of horizontal centrifugal mass finishing andvertical mass finishing are analyzed through changing the direction of the cylinder axis. The simulation results show that in the vertical mass finishing, themovement of abrasive is fiercer, the difference between the abrasive andworkpiece mutual effect is bigger than the horizontal mass finishing.2. The influence of fill rates is analyzed by setting different fill rates on themass finishing. The simulation results show that the velocity of abrasive isdifferent from each other, and the effect on workpiece is bigger when the fillrate is30%, the velocity of abrasive is very small and the relative movement isvery weak, the abrasive can’t form forced flow layer when the fill rate is90%;the forced flow layer is obvious, the processing flow layer is longer and thevelocity of slip layer abrasive is well-distributed when the fill rate is50%or65%, which is good to processing.3. The influence of transmission ratio on the mass finishing is analyzed bysetting different transmission ratio. The simulation results show thattransmission ratio has certain range through analyzing the average velocity ofabrasive, the normal and tangential force of workpiece, there is the besttransmission ratio n/N to achieve ideal processing effect.4. The process parameters such as the eccentric block angle, processingdepth and the champing angle of fixed workpiece are analyzed. Testing datashow that the angle of eccentric block has important influence on the movementof abrasive and the force of workpiece; the mutual force of abrasive andworkpiece increases with the increase of buried depth, but the growth spurtbeyond certain depth; the movement of workpiece in the process is periodic; the abrasive flow gather together when the clamping angle α is20o, and the force ofthe workpiece reaches the maximum.The movement of abrasive, the force between abrasive and workpiece wereanalyzed by using EDEM software in the microscope aspect, besides, the forceof vibratory mass finishing was tested and analyzed, which perfect the theory ofthe mass finishing and fill the blank of quantitative analysis of mass finishing.