在详细分析换热器钛合金管板自动焊接工艺特点的基础上,利用自行研发的全数字管板焊接系统进行了换热器管板的全位置自动焊接工艺试验,探讨了换热器管板焊接中影响焊接质量的相关因素,获得了合理的工艺,即峰值电流80~100A、基值电流20~30A、电流脉冲频率5~10Hz、脉冲占空比50%、机头转速3~4 r/min、采用脉冲方式进行电流上升和下降,并在1GW超临界火电机组换热器管板的焊接生产中证明了所确定的焊接工艺能满足实际施工的需要.

In this paper,the characteristics of the all-position automatic welding procsss for the titanium alloy tube sheet of heat exchanger were analyzed in detail,and some experiments were carried out by using a self-developed full-digital tube sheet welding system.Then,the effects of the main process parameters on the welding quality were explored,and optimal conditions for the welding were determined,that is,a peak current of 80～100A,a base current of 20～30A,a pulse current frequency of 5～10Hz,a duty ratio of 50%,a rotating speed of 3～4r/min and a pulse mode for the current rising and falling.Finally,the correctness of the optimal conditions was verified by the on-site welding of tube sheet of heat exchanger for a 1GW supercritical thermal-power generating unit.