Submerged arc welding defects

Common defects and their causes in submerged arc welding are as follows:

1. Porosity
Causes: Damp flux, oil/rust on the groove, excessive welding speed, excessive wire extension, excessive arc voltage.
Solutions: Dry the flux, clean the groove, adjust speed and voltage, control wire extension length.
2. Lack of Fusion/Lack of Penetration
Causes: Insufficient current, excessive speed, small groove angle, improper wire position, excessive flux layer thickness.
Solutions: Increase current, decrease speed, correct groove angle, adjust wire position.
3. Undercut
Causes: Excessive current, excessive voltage, excessive speed, improper wire angle.
Solutions: Reduce current and voltage, adjust speed, correct wire angle.
4. Slag Inclusion
Causes: Insufficient current, excessive speed, incomplete inter-layer slag removal, high flux viscosity.
Solutions: Increase current, thoroughly remove slag, adjust flux viscosity.
5. Cracks
Causes: High sulfur and phosphorus impurities in base metal/welding rod, high welding stress, high hydrogen content.
Solutions: Control impurity content, preheat/post-heat treatment, select low-hydrogen welding rods.
6. Weld Size Problems
Causes: Inconsistent groove angle/width, improper electrode diameter, uneven current/speed.
Solutions: Standardize groove dimensions, adjust parameters, improve welding technique.