About steel pipe of welding operation

As the molten pool is located below the weldment, the higher the temperature, the gravity of the molten metal of the electrode will hinder the excessive falling. The larger the volume of the molten pool, the smaller the surface tension of the molten pool, and the molten pool metal will fall under its own gravity. Therefore, during overhead welding, the back of the weld is easy to sag, and there will be weld beading on the front, which is difficult to form a weld bead

What are the key points of overhead welding operation?

1. During overhead welding, attention must be paid to maintaining correct operation posture. The welding point shall not be directly above the person, but in front of the upper part, and the weld shall be on the right side of the operator.

2. Small diameter electrode and small current welding are adopted.Generally speaking, the welding current of overhead welding is between that of horizontal welding and vertical welding.

3. Short arc welding to promote droplet transfer.

4. Maintain correct  mode.

5. If the molten pool temperature is too high, the arc can be raised slightly, which can reduce the molten pool temperature.

6. During overhead welding, due to the action of welding gun and gravity, the welding personnel are prone to gun instability. At this time, they need to hold the gun with both hands for welding.

7. During inclined round bar transportation, the welding rod head shall be upward first to make the molten drop fuse with the upper plate first. Due to the action of the conveyor belt, part of the molten metal will naturally be dragged onto the steel plate of the facade,so that it can be fused twice evenly.

8. Short arc welding of 0.5 ~ 1mm shall be maintained during . Do not drag the covered electrode head onto the weld to avoid narrowing and convexity of the weld

9. Keep uniform welding speed and correct electrode angle, keep short arc, and the upward feeding speed shall be consistent with the combustion speed of electrode

10. It is best when the molten pool surface is flat or slightly concave.When the temperature is high, the molten pool will bulge or bulge outside the surface, and flash will appear in severe cases.