The Design Of The Piggable Color-Changing Control System For Automobile Spraying

With the rapid economic development,people’s demand for cars is increasing.The user’s demand for personalized and diversified of car colors is increasing,and they are no longer only satisfied with the four basic colors of white,black,silver,and gray.However,the "traditional circulating pipeline system" usually used in the automotive spraying workshop can no longer meet the needs of quickly switching a variety of personalized colors.In order to solve the problems of long paint color change time,difficultly clean pipe,easy to cause color difference,color mixing,low production efficiency,and large waste of paint and solvents in the coating production of an automobile factory,a set of piggable color-changing control system based on HMI formula was designed and developed.The research content mainly includes the following aspects:(1)Taking the piggable color-changing control system in a spraying workshop of an automobile factory as the research object,the system function requirements,equipment composition and paint color change process flow are analyzed.And designed the overall structure of the piggable color-changing control system based on HMI formula.(2)According to the design structure,the hardware configuration of the piggable color-changing control system is selected and built.Including PLC and external expansion module selection,switch selection and PROFINET configuration,electric control cabinet panel HMI selection and explosion-proof operation box design,PN/PN coupler selection,other sensor selection and electrical control cabinet power supply wiring Wait.And use EPLAN software to draw the wiring schematic diagram of the electrical control cabinet.(3)Research the software control scheme of the piggable color-changing control system based on HMI formula,by analyzing the process flow of paint filling,paint recycling and solvent cleaning,the program control flow chart is drawn.Use TIA V15 Portal software to design and develop PLC main control program and HMI screen program.The screen includes the base station,the distribution station technology interface,the system operation monitoring interface,the parameter setting interface,the PN/PN interactive interface and the alarm interface,etc.(4)Debug and run the control system,and carry out experimental debugging of various functional modules of software and hardware,including communication debugging,valve terminal debugging,current compilation process function and system operation debugging.This system chooses S7-1500 PLC and HMI smart panel as the core control device and human-computer interaction window respectively.Experiments have proved that the system has a short color change time and can switch between two colors within 45-60 minutes;it achieves the purpose of easy cleaning(one cleaning can meet the standard),and there will be no spray color difference,color mixing after the pipeline is cleaned;And about 85.7% of the paint in the pipeline can be recycled for reuse.Compared with the traditional circulating pipeline system,this system saves nearly 82.8% of the cleaning solvent,laying a foundation for the green development of the industry.The system has been put into production.According to the application results,it is shown that the system can not only meet the process requirements of rapid paint color change,but also runs stably and reliably,which greatly improves the production efficiency of the workshop and saves a lot of economic expenditure for the enterprise.