Research On Control System Of Step Pressure In Vacuum Differential-pressure Casting

Vacuum pressure casting technology has a broad application prospects in theaviation, aerospace, defense, automotive industries, and almost no margin casting,complex aspects of nonferrous alloys which are large, thin-walled. With the nationalbasic industry requirements about the quality of casting continuously improve, vacuumpressure casting control system is facing such enhanced functionality and performancerequirements and other requirements. This topic is in the mold filling and solidificationof the relevant theory, proposes the design scheme of the vacuum pressure castingsystem about classification of pressure control at the same time.Based on the analysis and the principle of vacuum pressure casting process, thisarticle comprehensively design the vacuum pressure casting system from three-partsections, which are hardware, microprocessor module control software, PC remotecontrol software of the casting system. The system adopt distributed structure to realizethe graded compression process and monitoring of furnace temperature control. furtherenhance the effectiveness of the entire system of control with the simultaneousobservation of press and temperature parameters in foundry technology processIimprove theVivacity of man-machine interface by means of the powerful functionof pc. At the same time, the data storage and printing function provide a goodfoundation for promoting casting process management level. The system hardware partof the circuit design includes a main microprocessor circuit, the pressure detectioncircuit, electromagnetic valves drive circuit, the digital input interface circuit, LEDpressure display circuit, RS-485communications interface circuits, power supply circuitmodule design. Microprocessor control software module is the key of realizing thegraded compression process and controlthe whole casting process,it includes the mainprogram design on the monitoring section, data acquisition module design, PID controlmodule design, the realization of graded compression process control design, datacommunication module, data display module design and so on; PC Remote MonitoringSoftware is developed with Visual C++programming tool,achieve remote control andcentralize management by Object-Oriented method. The platform consists mainly ofSettings of Process parameters, view switching, printing performance results for therendering of Process,and so on. Finally, verified the effectiveness of the method in the control of Vacuum Differential-pressure Casting by debugging and experiment of thesupposed system.The vacuum pressure casting network control system of grading pressure designedby this project, using RS-485bus for the process of casting, temperature, flow and otherparameters for network measurement and control, not only meet the need of the large,complex castings production in Vacuum pressure casting system,the but also has animportant Significance for further research and improve the level of precision castingtechnology.