System Design And Character Analysis Of 2-dimensional Electro-hydraulic Flutter Cold Extrusion Vibration Platform

Cold extrusion is one of the main methods of plastic processing.It has the advantages of"high quality","high utilization rate" and "low energy consumption" and so on.It is widely used in the fields of construction,aviation,transportation and communications.However,in the extrusion process of the part,there are problems that the forming pressure of the extrusion is large,the life of the mold is low,and the part is formed unevenly.In response to the above problems,our group introduced vibration into plastic processing.In a previous study,the research team used axial flutter to extrude bush parts to reduce the amount of forming force and promote metal flow.However,the experimental results of axial flutter are still imperfect,and the axial vibration table has the defect that the vibration amplitude and vibration frequency can not be accurately controlled,which cause the experimental and application needs can not be satisfied.Therefore,this paper designed a two-dimensional electro-hydraulic cold extrusion vibration table,witch suitable for cold extrusion plastic processing.By applying axial and radial electro-hydraulic excitation to the mold,it can vibrate at high frequency and low amplitude.The specific research contents are as follows:(1)The working principle of two-dimensional flutter cold extrusion vibration table is introduced,that is,the electro-hydraulic servo valve is used to control the reciprocating motion of the piston in the initial vibration center position,so as to drive the vibration test platform to achieve high frequency and small amplitude vibration.The axial vibration generator and the radial vibration generator are designed,and the vibration simulation of the vibration plate is carried out.(2)A mathematical model was established for the axial generator and the radial generator of the vibrating table with flutter and cold extrusion respectively,and the stability of the system was analyzed.The simulation model was established by Simulink to analyze the displacement of the hydraulic cylinder under different input conditions.Using Solidworks,Adams and Ansys to establish a rigid-flexible coupling model,the overall vibration performance is analyzed.(3)According to the functional requirements of two-dimensional flutter cold crushing vibrating table,the corresponding hardware circuit and software system are designed.(4)Set up a two-dimensional experiment platform;Measure the vibration amplitude of the vibration table by using the laser displacement sensor,and compare the experimental results with the simulation results;Finally,complete the experiment of squeezed sleeve parts and measure the stroke load under two-dimensional flutter.The results show that the effect of two-dimensional chattering is more obvious than that of axial chattering.In summary,the two-dimensional vibration table designed in this paper is suitable for cold extrusion processing,two-dimensional vibration can reduce extrusion forming force.This technology can provide an effective way for the high quality forming of the traditional hard forming parts in the press with low tonnage.