Simulation Analysis Of Gap Field In Slotting Process Of Sand Control Screen Pipe By EDM

Petroleum slotted screen pipe is an essential mechanical equipment in petroleum exploitation.Its processing quality directly determines the oil exploitation rate.There is no mechanical force and high machining quality in EDM,which has a great advantage in slotted screen tube machining.The machining principle is to use the high temperature generated by the pulse discharge between the sparks to realize the process of metal removal.It is the result of the joint action of electromagnetic force,thermal force and flow field force.Therefore,in order to know more accurately the changes in the slotting time gap of EDM,it is of great significance to study the gap field of different stages.In this paper,firstly,the current research status of the slotting mode,the temperature field,the flow field and the electric field of EDM at home and abroad is analyzed,and the temperature field model at the discharge point is established based on the high-temperature erosion process of metal discharge,and the change rule of the temperature field when the discharge time is less than the pulse width is obtained;by setting the peak current and the pulse width of different numerical values In order to get the quantitative relationship,the regression equation between the peak current and pulse width and the etched pit is established by using the method of surface center combination design,which is convenient to predict the pit size under the given peak current and pulse width;and Genetic algorithm is used to solve the regression equation,and the optimal combination of electrical parameters is obtained.The workpiece removed after EDM will be thrown into the working fluid as the product of EDM,and it is an important reason for the high quality of EDM that the working fluid can discharge the debris smoothly.In order to better guarantee the discharge of the product of EDM,the flow field state of the gap in the machining is modeled,and the different punching methods,electrode shape,discharge gap,machining depth and punching hydraulic pressure are studied The variation of working fluid velocity and particle distribution of erosion products under force;in view of the fact that the electrode does not have the problem that rotating motion will affect the normal chip removal during slotting,ultrasonic vibration is applied to the electrode,and the flow field of the gap under different vibration amplitude and frequency is obtained;in order to study the relationship between the discharge gap,processing depth,flushing pressure,amplitude and vibration frequency and the concentration of erosion products According to the influence relationship between degrees,the orthogonal test table is established to get the simulation results,and the influence degree among the five factors is sorted,which provides reference for EDM slotting in the future.In order to study the influence of the existence of the erosion products on the In order to study the influence of the products of electric erosion on the electric field when the dielectric is broken down,the electric field model of EDM is established.Taking the maximum electric field strength in the gap as the measurement standard,the law of electrode shape,pulse voltage,machining gap,particle diameter,particle position,particle accumulation and electric field distribution is studied,the change curve is obtained,and various phenomena are analyzed According to the influence of particles on the electric field,the mechanism of powder mixing process is obtained,which provides the best concentration reference for powder mixing process.