Railhead repair by gas metal arc robotic slot welding: An evaluation of newly-developed technology

摘要

Several hundred thousand thermite and flash-butt welds are installed in North American railway systems each year. These welds provide a suitable joint through the cross section of the rail. However, neither type possesses mechanical performance equal to the parent rail. Thus, to optimize the performance of the continuously welded rail, these welds should be kept to a minimum. An alternative repair weld, called a slot weld, has been developed by The Holland Company. This process, which can be used for field repairs of the railhead, uses robotic gas metal arc welding, GMAW, and can repair head defects to a reported maximum depth of 0.75 inch, without cutting all the way through the rail; thereby replacing two regular welds that would normally be necessary to repair a railhead defect.