How to avoid slag inclusion during steel structure welding process？

During the welding process of steel structures, slag inclusion is caused by the slag not floating to the surface of the molten pool and remaining in the weld seam. To minimize the generation of slag inclusions, the following measures can be taken:

1 Choose the appropriate welding current and welding speed. The welding current should not be too small and the speed should not be too fast, so that the slag has enough time to float to the surface.

2 Remove any surface impurities on the weld, such as rust, oxide scale, paint, or any coatings, to avoid the generation of slag inclusions.

3 During the welding process, pay attention to the direction of slag flow, adjust the angle of the welding rod and the transportation method at any time, so that the slag can float smoothly to the surface of the molten pool.

4 For multi-layer welding, the interlayer coating must be cleaned thoroughly to prevent debris from entering the melt pool.

5 Try to use short arc welding to avoid excessive arc length that may cause slag to float to the surface. At the same time, it is necessary to strictly control the current parameters and welding speed.

6 For acidic welding rods, appropriate electrode diameter and welding current should be selected to avoid too thick or too thin slag; For alkaline welding rods, appropriate coating or flux should be selected to reduce the melting point and viscosity of the slag, which is conducive to preventing the generation of slag inclusions.

7 During the welding process, frequent stops and restarts should be avoided as much as possible to prevent impurities from floating out of the molten pool.

8 For difficult to operate parts such as vertical welding or overhead welding, welding rods that can be welded in all positions should be selected to ensure welding quality.

In summary, in order to avoid slag inclusion during the welding process of steel structures, it is necessary to start from multiple aspects, including selecting appropriate welding parameters, removing surface impurities, adjusting the direction of slag flow, controlling interlayer cleaning of multi-layer welding, and using appropriate types of welding rods. The reasonable application of these measures can effectively reduce the generation of slag inclusions and improve the quality of steel structure welding.