闪光焊最佳参数的自动建立——一种新型的高效率闪光焊过程

THE SELF-ESTABLISHMENT OF THE OPTIMUM TECHNICAL PARAMETERS OF FLASH BUTT WELDING

摘要:

闪光对焊加热过程的特点与电阻对焊相比较是不连续的。闪光焊机的动板运动如能适应这一不连续性,即应与触点的瞬时过程相一致,闪光过程的稳定性和加热效率就会进一步提高。本文对闪光加热的这种不连续性进行了分析对比,提出了以触点实际过程为基础的瞬时调节方案。根据这一方案设计了相应的闭环电液伺服控制系统。这一系统的试验结果表明,闪光过程的稳定性大为提高,实现了动板宏观送进自动适应工件闪光烧化速度的增长,焊机不再需要预先给定运动方式和送进曲线。由于加热效率大幅度提高,闪光比功率可降低至常规送进法所需比功率的十分之一,对节能有重要意义,已经用这一方法为工厂生产了成批刀具,使用情况良好。

Abstract:

One of the essential characteristics of flash butt welding is the discontinuity of the flash heating process caused by the contact bridges.If this characteristic is adopted as the principle of the platen movement control,the stability and the heating efficiency of flashing proceess Can be increased drastically.A closed loop electro-hydraulic servo control system has been designed and applied to a conventional general purpose welding machine.With this system the control of platen motion according to the instantaneous process of the individual contact bridges can be achieved.By means of instantaneous regulation of the platen movement the macro velocity of the moving platen can be self-adjusted to suit the changes of the melting speed of the workpieces and the required specific power can be reduced down to only one tenth of that with conventional predetermined platen movement control.