During the welding process, the melting depth exceeds the thickness of the pipeline, and the melting metal flows out of the back of the weld to form perforation.
(1) Harm
It destroys the denseness of the weld and the loss of the connection and bearing capacity of the welding joint is a defect that does not allow existence on the pressure pipeline.
(2) Cause analysis
The welding current is too large, the speed is too slow, and the arc stays at the weld for too long, which will cause burning flaws;
The space between the weld is too large, and the blunt side is too small and it is prone to burning.
(3) Control measures
When welding, select the instrument diameter according to the thickness of the pipeline wall, and then select the welding current according to the instrument diameter, and be equipped with the appropriate speed of the tank;
Prioritize the cutting of the pipeline by cutting. If the oxygen one acetomo flame is cut and cut off, the incision should be polished to eliminate the bumps;
When the pipe is opposed, the gap between the connector is uniform, and not too large or too small;
Pay attention to the stop time on both sides of the slopes.
