Numerical Simulation And Process Research On Die-casting Filling And Solidification Process Of T-valve

High pressure die-casting is a method in which a liquid or semi-liquid metal is filled in die-casting mold at a high speed and high pressure,and solidified to obtain a casting part under a certain pressure.Compared with other casting methods,high pressure die casting has the following three advantages:good product quality,high production efficiency,and excellent economic results.Die-casting is one of the most advanced metal forming methods.It is an effective way to achieve less chipping and no chipping parts.It is widely used and develops rapidly.The T-valve is an important part of the pipe conmection,and the quality requirement is very strict.The structure of the T-valve is more complicated.The part's shape is almost cylindrical.There is a flange on the left side.A symmetrical curved through-holes and a stepped circular hole on the flange.And there is a fixed base on the lower surface and a square through-hole in the cylinder.The gas,temperature field and oxidation inclusion model were turned on in the Flow3D software for simulation analysis.Analyzing the filling process of the gating system design scheme 1,and found that there is an unfilled condition in the runner,so the curve is designed on the runner,the filling speed is appropriately reduced,a good filling process is obtained,the position of the overflow groove is designed according to the location where the molten metal is initially impacted.In the improved scheme 2,the runner is already filled before entering the mold,but after the filling process is finished,and analyzed the overall temperature,the distal temperature was lower,so the scheme 3 is designed.And the auxiliary casting system is added to make the distal end is connected to the ingate to obtain an earlier filling,and the overall temperature of the casting is more uniform.However,the casting gas content is also in a high level,so designing the scheme 4,by optimizing the form of the overflow groove to reduce the internal gas content,finally achieved good results.By analyzing the metal material properties and the filling and solidification process,the shrinkage content and the solidification time,the selection range of the process parameters was designed and the optimized scheme was finally determined.The optimum process parameters are set as follows:the casting temperature is 700?,the preheating temperature of the mold is 200?,and the injection speed is 2m/s.Under this set of parameters,the shrinkage content in the parts are the least,and the solidification time is moderate,which can be considered as the best parameter.According to the optimized T-valve gating system,the mold was designed,the model of the die-casting machine was selected,and the simulated optimization process parameters were set in the die-casting machine for trial production,and the casting parts has smooth surface and good quality.It shows that the numerical simulation results are correct and can be used to guide production.