在国内铁路高速发展的背景下，钢轨焊接质量显得尤为重要。钢轨气压焊以其焊接方便、成本低，且能保证焊接质量的特点成为最具有竞争优势的焊接方法之一。目前，在中国铁路行业应用广泛的移动式气压焊轨机焊接接头质量影响因素多，特别是受人为因素影响大的缺点。针对这种情况，西南交通大学焊接研究所成功研制了基于PLC的数控式小型气压焊轨机，焊接接头质量的合格率高而稳定，得到了很好的评价。但是由于现场焊接设备移动频繁，系统各部件之间的连接电缆在使用过程中常出现破断现象，造成设备故障率高，由于电缆芯数多，设备维护困难，推广使用形成阻碍，因此，立题进行研究。
目前应用的移动式数控气压焊，故障率最高的是高压泵站和控制箱之间的连接电缆，由于铁路沿线强电磁场的干扰，本课题仍基于有线通讯来实现高压泵站和控制箱之间的信息交换，通过减少信息交换的电缆芯数来降低设备故障和维护难度。采用CAN总线实现高压泵站和控制箱之间的通讯控制，CAN总线为两线制串行通信总线，具有高位速率和高抗干扰性的特点，大大减少了电缆芯数。
采用主节点加下位机数据采集、控制模块的主从结构设计了基于CAN总线的控制系统的软件和硬件。硬件主节点由单片机AT89S52、CAN独立控制器SJA1000与CAN收发器82C250构成；下位机模块则是采用周立功公司的ICAN系列工业模块；采用C语言编写了相关软件，主要包括初始化CAN控制器、发送命令帧、接收并处理返回帧数据等几大功能模块。
对制作好的硬件和软件进行了模拟调试，结果表明：软硬件能实现油压、顶锻量的恒值控制，以及钢轨焊接过程的时序控制。

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.