Research On Sand’s Flowing And Filling In Multidimensional And Frequency Conversion Lost Foam Vibration Table

EPC(Evaporative Pattern Casting)has the advantages of minimum pollution and low cost due to its unique technology.With the rapid development of EPC,it also encounters some technological difficulties.The vibration compacting of sand,as one of these aporias,is considered as the key factor of the technology of EPC.Nevertheless,there are few researches on the flowing and filling function of sand.Therefore,this dissertation aims at filling the blank by using methodology of theoretical analysis,analogue simulation and experimental verification.First of all,the author analyzes the lost foam vibration table,which has been widely applied in foundry,including its structure,vibration principle,parameter calculation and the factors that may impact the vibration.Such theoretical analysis would lay a solid foundation for the following experiments: the sand’s horizontal and vertical filling experiment and the analogue simulation.Secondly,the paper introduces a series filling experiments.Under the condition of setting motor frequency to 50 HZ,the author finishes the experiments of uni-dimensional,two-dimensional and three-dimensional filling of the vibration table,as well as the experiment on how high-frequency vibration impact the flowing in sand filling process.Thirdly,the path of relevance particle has been simulated when a double electric motors lost foam vibration table is working.The author not only analyzes the simulation,but also verifies the conclusion by experimenting thoroughly.The sand’s horizontal filling experiment shows that if the sand box has been set tightly to the vibration table,the utilization of vibration energy would be enhanced,which dedicates to the flowing and filling of the sand.While increasing the frequency of electric motors is an efficient way to improve the sand’s flow and shorten its filling time.the simulation and verification experiments indicate that the change of the angle of eccentric block in electric motor would enlarge the exciting force,which could also benefit to increase the sand’s flow and curtail its filling time.In addition,if the exciting force has been enhanced to a reasonably scale by a reasonable way,the sand can fully fill the vertical foam cavity.In conclusion,this research provides a solution to a series of problems such as how to regulate vibration table and how to make the sand fully fill the foam cavity and so on.