Research On Control Strategy Of Internal High Pressure Forming Machine Based On Servo Electric Cylinder And Trial Production Of Typical Pipe Fittings

The situation of energy conservation and emission reduction in the automobile industry is grim,and the development of lightweight technology is imminent.However,due to the late start of this technology in China,the relevant enterprises do not have a high understanding of it,and the application of this technology is still in a wait-and-see state.Therefore,in order to promote the application of internal high pressure forming technology,so that the internal high pressure forming technology can be better developed and popularized,it is necessary to study the internal high pressure forming technology.Aiming at the problems existing in the existing internal high-pressure forming equipment,this paper takes the S30408 austenite stainless steel seamless tube with the specification of Ф50.8mm×1.4mm ×160mm as the research object,mainly carried out the synchronous control strategy of the side cylinder position of the internal high-pressure forming machine based on the servo electric cylinder.The work carried out in this paper includes:1.Research on internal High pressure forming based on traditional hydraulic cylinderBy analyzing the working principle and key technology of each component of the existing forming equipment,the design parameters of the equipment are clarified.Through THE material test of the tube blank,the process parameters of the hydroforming of the tube are calculated,and the design parameters of the existing equipment are compared,which proves the feasibility of using the existing equipment to carry out the experiment theoretically.According to the hydroforming process parameters and the length of the initial tube blank,the forming die of the variable diameter tube is designed.According to the theoretical calculation of the total filling amount and process parameters of the variable diameter tube hydroforming forming experiment,through the analysis of the experimental results,the existing problems of the existing equipment,and based on this proposed equipment improvement scheme.2.Component selection and tooling design of internal high-pressure forming equipment based on servo electric cylinderIn order to ensure that the servo electric cylinder can meet the experimental conditions,according to the hydraulic forming process parameters of the variable diameter tube and the working space of the side cylinder,the selection and calculation of the electric cylinder are carried out,and the corresponding equipment is designed according to the experience and suggestions of the engineering personnel.3.Control strategy research and control system developmentIn order to realize the accurate tracking of the given displacement curve of the side cylinder,based on the control model of the unilateral electric cylinder based on PID controller,combined with the control strategy of "equal+master-slave",the MATLAB/Simulink module is used to model the synchronous control system of the side cylinder position.The performance of the designed control system is evaluated by observing the tracking of the given signal and the simulation results of the synchronization error of the side cylinder under three typical excitation signals.The internal high pressure forming machine based on servo electric cylinder is built,and the corresponding control system development and program debugging are carried out based on this.4.Experimental study on typical tube fittings of internal high pressure forming machine based on servo electric cylinderOn the one hand,in order to improve the numerical simulation accuracy of the hydroforming process of the variable diameter tube,the circumferential mechanical parameters of the tube are applied to the simulation of the hydroforming process of the variable diameter tube,and the hydroforming law of the variable diameter tube is studied by combining experiment and simulation.Through simulation optimization,the loading path of variable diameter tube samples with good forming quality is obtained.On the other hand,in order to verify the rationality of the design of the servo electric cylinder tooling structure and the effectiveness of the control algorithm,the optimized loading path is used to conduct experimental research on the variable diameter tube.