Research On Control Method Of Low Pressure Casting Liquid Level

Low-pressure die casting is one of the special casting technologies.The liquid level control technology is the core of low-pressure casting.The pressure value,response speed and response accuracy directly affect the molding quality of the Low-pressure die casting.How to reasonably determine the pressure value and ensure that the actual pressure in the holding furnace well follows the theoretical pressure curve is the key to achieving low pressure casting.he pressing value of the casting is determined by the experience of trial production,which results in a long production cycle and high cost of the casting.This paper will develop from two angles of how to determine and realize the pressure process value,and provide theoretical and technical support for how to improve the quality of castings,shorten the production cycle,increase the production rate and reduce the production cost.In terms of how to determine the value of the pressurization process,the paper firstly establishes the corresponding casting and mold models in the 3D software UG(NX),and then introduces the numerical simulation software ProCAST to perform mesh division,initial condition determination and boundary condition setting.Firstly,the single-gate underfill system was used for simulation analysis.It was found that the liquid level instability was serious and the casting defects were obvious.The analysis of the pouring system and pressure values was improved.The simulation was carried out by using the cross-bottom injection system and the optimized pressure curve.Fill the result to determine the final pressurization value.After the pressure value is determined,a pneumatic control scheme is proposed,and the corresponding components are selected through calculation and analysis and consulting with relevant product manuals.The corresponding pneumatic control model is built in AMESim,and the relevant parameters are set for simulation analysis.The analysis results show that the control results have hysteresis.The fuzzy self-tuning PID control system is introduced to accelerate the response speed of the system.The joints are established in AMESim and Matlab respectively.The simulation model,through simulation analysis and research,can make the actual pressure in the holding furnace to match the theoretical pressure numerical curve to the greatest extent.