樊世平

【摘 要】钢轨闪光接触焊是一种生产效率高，质量稳定可靠，自动化程度高的钢轨焊接方式。随着我国铁路建设的飞速发展，施工单位在现场都普遍采用移动式闪光焊接，既保证了建设工期，又提高了焊接接头的质量。如何获得一个高质量的焊头，首先要从闪光焊的工艺参数做起，参数设置多，调整思路广泛，落锤结果往往很难把控。热处理轨由于强度好，耐磨性高，越来越多地被铺设到高速铁路中，但是淬火轨的焊接难度普遍认为较高，型检落锤要耗费大量的钢轨，所以我们对热处理轨的焊接工艺来进行详细的分析。

【关键词】闪光接触焊;工艺参数;热处理钢轨

Study on Flash Welding Technology of Heat Treated Rails

Fan Shi-ping

（China Railway First Bureau Group New Transportation Engineering Co.， Ltd Xianyang Shanxi 712000）

【Abstract】Rail flash contact welding is a kind of rail welding method with high production efficiency， stable and reliable quality and high degree of automation. With the rapid development of China's railway construction， the construction unit generally adopts mobile flash welding at the site， which not only ensures the construction period， but also improves the quality of welded joints. How to obtain a high-quality welding head， first of all from the process parameters of flash welding， parameter settings， adjustment ideas are wide， the drop hammer results are often difficult to control. Due to the good strength and high wear resistance of the heat-treated rails， more and more are laid into the high-speed railway. However， the welding difficulty of the quenching rails is generally considered to be high， and the type of check hammers consumes a large amount of rails， so we have to heat the rails. The welding process is used for detailed analysis.

【Key words】Flash contact welding;Process parameters;Heat treated rail

1. 脉动闪光焊接工艺

（1）钢轨闪光接触焊是一种以塑性变形再结晶过程。两个待焊轨存在接触电阻，当电流流经钢轨时就会产生电阻热量，所产生的热量和电阻大小成正比，与电流大小的平方成正比。在钢轨端部由于电流流经电阻产生热量，使钢轨端部迅速加热、被加热烧化，形成金属“过梁”进一步加热，“过梁”加速，“爆炸” 形成金属火花从钢轨间隙中射出，这就是闪光，随着钢轨端部温度的提高，闪光就会愈来愈激烈，在闪光加热过程中，钢轨端部逐渐达到溶化温度，在高温下，迅速施加相当大的挤压力，在钢轨相接触的界面上，就会产生塑性变形再结晶过程，使两根钢轨连接成为一个整体，形成焊接接头。焊接接头质量是与钢轨材料的化学成分、轨种、生产厂家有密切联系，并不是所有的钢轨材料都具有同样的良性。……