Research On Monitoring And Control System Of Stationary Welding Machine In Unmanned Rail Welding Workshop

With the implementation and advancement of “Made in China 2025” and supply-side reforms,the pace of transformation from processing and manufacturing to intelligent,networked and unmanned production modes is getting faster.Although the rail welding technology in the construction of domestic high-speed rail seamless lines has a good foundation,no matter whether it is the digitalization of the welding production line equipment or the network management of the production workshop,there is still a big gap from the requirements of the unmanned welding workshop.Therefore,the research of unmanned production technology in rail welding workshop is conducive to the improvement of the overall technical level of rail welding in high-speed railway construction.On the basis of consulting relevant literature and analyzing the welding rail production line of Chengdu Welding Rail Base,one of the main welding rail bases in China,part of the design and development of the monitoring system for the unmanned rail welding workshop was carried out.It mainly includes the following aspects:(1)Based on Ethernet and field bus technology,the overall plan of the rail welding workshop monitoring system composed of the production monitoring and management subsystem and the operation planning management subsystem is designed: the operation planning subsystem is composed of three modules: operation plan management,operation plan status and historical plan query.This subsystem can help managers understand the processing capacity and status of the production line and perform optimal operation plan scheduling;the production monitoring,process monitoring,data management and system management of the production monitoring and management subsystem cooperate with each other to enable managers to understand the working conditions of the production line equipment and the processing quality of each joint in real time,and conduct the management of welding rail production through remote operation instructions.(2)Taking the rail conveying precise positioning and information interaction of the most complex stationary welder station in the welding production line as an example,an automatic rail conveying system is designed: the system detects the position of the rail on the roller line,the working status of each station and the logic requirementsbetween them through sensors in real time,and combines with the corresponding control algorithm to achieve precise position control of long rail transportation,through Ethernet and PLC data exchange,through the PLC substation and the field bus communication between the inverter,to achieve real-time collection,display and storage of inverter frequency adjustment and inverter fault type,operating status and other data,the visual centralized management and real-time monitoring of production line can be realized.(3)Add a sensor to detect the position of the rail and the moving parts of the stationary AC welding machine,combined with the proposed unmanned welding work flow,unmanned operation before and after rail welding is realized;(4)For the problem of automatic alignment of the welding joint of the stationary AC flash welding machine,the automatic alignment system software and hardware are designed and produced based on the laser sensor and PLC,the proposed variable-parameter PD control algorithm based on the size of the error solves the problems of the gap and response real-time of the centering mechanical structure,improves the dynamic performance and reliability of the system,and can better meet the requirements of automatic centering control.