Simulation And Optimization Of High Pressure Forming In T-shape Tube

In China,with the rapid development of the manufacturing industry,people have put forward higher requirements for components such as lighter weight and better stiffness.The use of light-weight,high-rigidity components in automobiles can reduce overall vehicle weight and save raw materials,while reducing vehicle fuel consumption and reducing exhaust emissions.Components based on internal high pressure forming have the advantages of reducing quality,increasing strength and stiffness,and reducing production costs,making them widely used in automobiles,aerospace and other fields.This subject takes the T-shape tube as the research object and studies the law of high-pressure forming in the T-shape tube.Through the combination of test and numerical simulation analysis,the effects of left and right feed,internal pressure,back pressure punch retreat,fillet radius and friction coefficient on the bulging height and minimum wall thickness of the three-way tube were investigated.First,the T-shaped t tube forming mold was designed and the T-shape tube was tested with the help of the existing internal high-pressure forming equipment.Using finite element software DYNAFORM to simulate the actual working conditions of T-shaped tube high pressure forming.Comparing the experimental forming results and numerical simulation results to verify the correctness of the finite element model establishment and simulation analysis.Second,based on the correct finite element model of the T-tube,investigating the influence of internal pressure,left and right feed,back pressure punch receding,friction coefficient and fillet radius on the bulging height and minimum wall thickness of T-shape tube.Thirdly,using the bulging height and the minimum wall thickness as the optimization objectives,the orthogonal test method was used to optimize the five process parameters.The optimal loading path within the selected process parameters is obtained,and the three parameters that have a great influence on the forming effect of the tee are selected.Fourth,using the response surface optimization method to optimize the selected three main process parameters.A quadratic polynomial regression response surface model was established for the bulging height,minimum wall thickness,and weighted target of the T-shape tube,and the model was optimized.Finally obtain the optimal loading path and use the optimal loading path for the T-shape tube forming experiment.Orthogonal test and response surface optimization methods were used to optimize the loading path of T-shape tube.The results showed that: The importance of the internal pressure,the amount of left and right feed,the amount of back punch retraction,the radius of the fillet,and the coefficient of friction on the bulging height from the largest to the least are: internal pressure,fillet radius,friction coefficient,left and right feed,back pressure punch retreat;The importance of the minimum wall thickness from big to small is internal pressure,fillet radius,friction coefficient,left and right feed amount,back pressure punch retreat amount;As the friction coefficient decreases,the bulging height of the T-shape tube increases and the wall thickness distribution becomes more uniform.The good lubrication environment has a great influence on the high pressure forming quality in the pipe fittings.Therefore,the friction between the mold and the pipe blank should be minimized in the actual production process.Orthogonal test method and response surface optimization method can quickly find the loading path formed by the T-shape tube.The T-shape tube with bulging height close to 1 times the original tube diameter and the minimum wall thickness reduction rate of no more than 20% can be obtained by experimenting with the optimized loading path for the three-way tube.This meets production requirements.This article is based on a combination of experimental and numerical simulation methods.Completion of analysis of high pressure forming law in T-shape tube.Orthogonal experiment and response surface optimization method are used to optimize the loading path of the T-tube and find the optimal loading path quickly.Therefore,this paper provides reference for the production of T-shape tube in engineering practice.