Design Of Distributed Test And Traceability System For Casting Furnace Temperature Based On Virtual Instrument

The temperature of the molten liquid inside the casting furnace directly affects the quality of the cast product.If the casting temperature is too high,it will increase the oxygen content and metal loss due to oxidation,which will not only affect the fluidity of the metal,but also promote the formation of cold insulation,increase the grain size and reduce the life of the mold.When the casting temperature is too low,the fluidity of the molten metal is poor,which is not conducive to the feeding.It is unfavorable for the removal of gas and slag in the molten metal.Based on the research of the industry-university-research cooperation project to quickly obtain the temperature of the molten metal in the high-temperature furnace,this paper also customizes the casting furnace temperature test system based on the fast thermocouple,which has important engineering application value.The main contents of this paper are as follows:(1)The system analyzes the working principle of the original temperature measuring instrument,proposes a new temperature measuring demand,and builds a distributed multi-instruments temperature measuring technology scheme.(2)The selection and integration of system hardware are based on virtual instrument,including temperature output module selection and peripheral circuit design,RS-485 gateway selection,furnace number selection and confirmation button,and host computer.The temperature output module collector is selected from NI myRIO-1900.The peripheral circuit is independently developed,and the power supply and signal comparator are integrated to correct and process the voltage signal output by the original measurement circuit.(3)The development of system software based on LabVIEW,including temperature output module software and host computer software.According to the system's requirements for software,the overall architecture of the software is built.Through multi-threading,state machine structure,queue technology and other means data acquisition,transmission,recording,editing and other functions are realized.The software runs stably and reliably,and takes up fewer resources.(4)The reliability verification test of the temperature output module reliability,test system accuracy and the overall function of the test system are carried out for the test system.The results show that the test system meets the design function requirements.The test system developed in this paper has high reliability,convenient operation and good expansibility,and has been applied in actual production.The system provides an effective means for casting furnace heating,furnace temperature monitoring,and information traceability inquiry.The research has certain theoretical and engineering application value.