Double-sided submerged arc welding direct welded steel pipe welding area

Introduction of welded pipe welding of submerged arc welding:
1, bubbles occur in the middle of the weld, the main reason is that hydrogen is still hidden in the weld metal in the form of bubbles, so eliminating the defects is the first step to remove the wire and weld corrosion, oil, moisture and humidity, followed by the need to dry the flux to remove water. In addition, increasing the current, reducing the welding speed and slowing down the melting speed of molten metal are also very effective.


2, a sulfur crack (sulfur caused by a crack). The weld zone segregation of sulfur separation zone crack, especially mild steel. The reason is that hydrogen exists in the sulfur separation zone containing iron and steel with low melting point. Therefore, in order to prevent this situation, it is also effective to use a small number of semi killed steel or seizing steel for sulfur separation. Secondly, it is necessary to clean and dry the welding surface and flux.