The Control System Based On CAN-BUS In Gas Pressure Welding Of Rail

On the background of railway's high-speed development in China, the quality of rail weld is particularly important. The gas pressure welding is convenience, low cost and can guarantee the welding quality. It has become one of the most competitive methods of weld. At present, when the gas welding machine, with application of a wide range in Chinese railway industry, welded joints, its quality can be affected by many factors, especially by human. In view of this situation, the welding institute of Southwest Jiaotong University successfully developed the mini-type CNC gas pressure machine, which welded joints, with high pass rate and stable quality, and received a good evaluation. However, due to the frequent movement of the welding machine in field and a number of multi-core cable, the cable between system components is broken often. This causing a high rate of equipment failure and equipment maintenance difficulties. This phenomenon hampers the equipment's promotion and use, so this subject was established to research it.At present, the connecting cables between high pressure pumping station and control box alwayes break. Because to the strong electromagnetic interference along the railway, this subject still achieve the exchange of information on the basis of wired communication, and the equipment failure rate and maintenance difficulty will be reduced, through reducing the number of cable cores. High pressure pumping station will exchange the information with control box through CAN-BUS, which is two-wire serial communication bus, with a high rate and high anti-interference features. This greatly reduces the number of cable cores.The whole control system was designed on the basis of the CAN-BUS master-slave structure, which included main node and the data module. The main node's hardware includes single chip AT89S52, CAN controller SJA1000 and CAN transceiver 82C250. The ZhouLiGong Company's ICAN industry module is chosen. The software was developed by C language, including initializing CAN controller, sending the command frame, receiving frame and processing the frame's data.Through simulation debugging, the result indicated the finished hardware and software could control the gas pressure constantly and the gas welding sequence.