Design And Manufacture Of Actuating Mechanism For Rail Ultra-narrow Gap Welding

As of the end of 2020,my country’s high-speed railway mileage reached 37,900 kilometers.Rails are an important part of high-speed railways.In recent years,with the continuous increase of railway operating mileage,passenger transport speeds,freight heavy loads,and traffic density continue to increase,various railway damages continue,and on-site maintenance tasks are becoming more and more onerous.The problem of in-situ welding repair is particularly serious.Traditional rail welding methods have been difficult to meet the requirements of in-situ welding and repair of rails.Flux band constrained arc ultranarrow gap technology is a new type of welding technology,which can realize the connection of thickwalled parts through single-layer multi-pass welding,and has the advantages of low welding heat input,high welding efficiency,and strong joint toughness.As long as the design is suitable Convenient equipment for on-site welding of rails can solve the problem of in-situ repair of rails.The harsh environment of the rail repair site places high requirements on the portability and ease of use of the rail ultra-narrow gap welding device.At present,the welding equipment designed by the research group still has problems such as inconvenient installation,low accuracy of welding gun neutralization,and unstable clamping of the cooling block.In this paper,focusing on the above problems,firstly,the overall layout of the steel rail ultra-narrow gap welding actuator and the overall design of the adjustment mechanism are proposed,and the design plan of the welding torch walking mechanism is proposed;secondly,a new generation of flux band constrained arc ultra-narrow gap welding torch system is designed and manufactured.The high-degreeof-freedom welding torch walking mechanism and the GM’s simulated welding machine can adjust the position of the welding torch;in addition,the clamping of the cooling block is also an important issue to be considered for the welding of rails with ultra-narrow gap constrained by the flux band.Compare in the design process A variety of cooling block clamping schemes are used to find a suitable cooling block fixture structure through mechanical analysis.Finally,the designed and manufactured ultra-narrow-gap welding gun actuator is used to conduct rail butt welding experiments on the basis of the arc ultra-narrowgap welding constrained by the flux band.The ultra-narrow gap welding actuator designed according to the welding result appraisal can meet the requirements of ultra-narrow gap welding.Obtained an ultranarrow seam welding device suitable for rail butt joints,which lays a solid foundation for futher optimizing the ultra-narrow seam welding process of steel rails.