Reconstruction Of AMS60 Rail AC Flash Butt Weiding Machine

Laying of continuous rail is very important in railway exploding development, the rail welding is the key step of high-speed railway laying project, and the high quality and efficiency welding machine has become absolutely necessarily element of rail welding. The AMS60 movable rail flash butt welding machine is used widely in Europe because it is of the characteristics of side automatic centering, good smooth-going, easy to adjust the welding joint arch, and it is especially fit to be used in the construction of passenger dedicated line and high speed railway. The first AMS60 weld machine in China was imported from Schlatter Switzerland by China Railway First Group Co in 2001. Because of it's high fault rate, it can't work normally from being used in rail construction, and so the reconstruction project was put forward to solve the high fault rate and halt.The head of machine was reserved as it has many advantages. The new control system has been designed and manufactured, the main circuit was designed through adopting double sets of thyristors to accomplish the voltage of high voltage stage and low voltage stage being controlled separately, and the experiment of rail welding is easy to be finished; Adopting PLC to control the welding progress and computer to monitor and control the welding parameters, the equipment reliability was improved; The energy control circuit and timing controlled circuit were designed, meanwhile the signal detection was improved, and by using the control method of reducing discontinuity the system's high fault rate was greatly decreased.The AMS60 movable AC flash butt welding machine has a long circuit and high circuit resistance, it is of small output welding current and slow di/dt, therefore it's difficult to adjust the welding procedure as comparing to Kseries ac flash butt welding machine. Aiming at behavior of AMS60, the research was finished based on U71Mn rail, It is found that through increasing the welding voltage and adopting double sets of thyristors the problem of small output welding current can be prevent.The appropriate welding process parameter has been found to past the technological test of TB and has been used in Beijing subway.