The hazards of the welding spatter of the rectangular steel pipe: reducing the welding deposition efficiency and reducing the welding productivity; the spatter is easy to adhere to the weldment and the nozzle, which affects the welding quality, makes the welding labor conditions worse and increases the cleaning time; the welding pool unstable, leading to defects such as rough weld shape. How to prevent splashing from happening? In the following words, we will introduce you five measures.
1. In rectangular steel pipe arc welding, there is a rule between the spatter rate of each diameter welding wire and the welding current: the spatter rate in the small current area is small, and the spatter rate in the high current area is also small, and the middle area has the largest splash rate. Therefore, when selecting welding current, avoid current areas with high spatter rate as much as possible.
2. The extension length of the welding wire should be short, which can reduce the welding spatter of the rectangular steel pipe effectively.
3. When the gas shielded welding machine adopts positive polarity, because the arc is affected by the anode spot pressure, the spatter increases sharply and the particles are large, so use the DC reverse polarity connection method.
4. Connect a large inductance in series in the welding circuit. When using medium current standard gas shielded welding, because the arc length is short, and the molten droplet and molten pool are constantly moving, the molten droplet and the molten pool are prone to short-circuit process, so the gas shielded welding except for the large droplet rejection transition , There is still a part of the molten droplet is a short-circuit transfer, a larger inductance is connected in series in the welding circuit, so that the short-circuit current rises slower, which can appropriately reduce the welding spatter of the rectangular steel pipe.
5. The spatter is the least when the welding torch is welding the rectangular steel pipe vertically. The larger the tilt angle, the more spatter. Practice has proved that the forward or backward tilt of the welding torch should not exceed 20°, and the maximum should not exceed 25°.