Measurement and analysis of arc pressure in two-TIG welding

Abstract

The distributions of the arc pressure at the anode surface along the directions of the tungsten electrode alignment (x-axis) and that perpendicular to the x-axis (y-axis) in two-TIG welding were measured and analyzed with the aid of the numerical results. The influences of the electrode spacing, the proportion of the current through the electrodes with the same total current, the total current and the arc length on the arc pressure were investigated. The results showed that the two-TIG arc pressure is significantly lower than the single-TIG arc under the same conditions, and the distribution range is noticeably reduced. As the tungsten electrode spacing increases, the arc pressure decreases, and the direction in which the arc pressure distribution extends changes from the x-axis to the y-axis. When the currents through the two tungsten electrodes are different, the arc pressure distribution in the x-axis is not symmetrical but symmetrical in the y-axis. As the current ratio or the total current increases, the maximum arc pressure increases and the deviation of the maximum arc pressure from the central point becomes more pronounced. The arc pressure decreases as the arc length increases, and its distribution range extends more along the y-axis.