The magnetic bias blowing during arc welding is due to the uneven distribution of magnetic field lines around the arc, which causes the arc to deviate from the welding axis. The appearance of this phenomenon makes the arc combustion unstable, the shielding gas protection is not good, and the droplet transition is irregular, resulting in welding defects such as poor weld formation, undercut, incomplete penetration, root or interlayer lack of fusion, pores, and even Some will suck the electrode (welding wire) or droplet to one side, which seriously affects the smooth progress of welding. Now some methods and measures to eliminate or reduce arc magnetic bias blowing are introduced as follows:
1. Try to use AC welding machine, small current, short arc welding and other methods to deal with this phenomenon.
2. Change the position of the ground wire.
(1) Connect the welding ground wire (bonding wire) to the middle of the weld.
(2) Connect the ground wires to both ends of the weld.
(3) Make the ground wire as close as possible to the welding position.
3. Welding torch cable winding method: After winding a part of the welding torch cable around any end of the welding port of the welded part (pipe) for a few turns, welding is performed. Weld the other end of the pipe mouth to see the effect such as, the purpose is to cancel the magnetic force produced by the magnetic field.
4. When the group is aligned, the multi-point solid welding method is used for tack welding, and the two nozzles are fixed in position, and then the normal welding of the electrode arc welding is carried out. Or bridging method positioning, can also play a role in degaussing.
5. It can be considered to use the electromagnetic control arc stabilization system for correction independently developed by Hangao Tech (SEKO Machinery) which obtained the invention patent for . In order to improve the efficiency of the production line and obtain good weld quality, the arc welding arc stabilizer developed by our company, in order to solve the above problems, adds a longitudinal electromagnetic field of adjustable size in the middle of the arc, and Stabilizes the arc in the middle by electromagnetic force. Or push forward, with electromagnetic stability, the arc will not swing backwards or left and right, the problem of undercut and "hump" will not appear. Therefore, the production efficiency is improved and the quality is ensured. The increase in speed of 20-30% has been verified in actual production. In order to adapt to different welding currents and production speeds, the electromagnetic force can be adjusted to suit different welding currents and speeds.
6. For butt welds with low requirements, oxyacetylene high temperature demagnetization method can be used on both sides.
7. Check the welding core of the electrode itself, and the eccentricity cannot be serious during manufacture, otherwise there will be eccentric blowing like the magnetic eccentric blowing.
8. When the arc blowing occurs during the welding of the electrode, the angle of the electrode can be adjusted appropriately, so that the electrode is inclined to the side of the blowing, and the length of the arc is shortened, which is practical and effective for the less serious blowing.
9. If partial blowing occurs during welding on the edge of the weldment, the arc strike plate and the lead-out plate can be fixed at both ends of the weldment, and then removed after welding, which can also play a role in reducing partial blowing.
10. Remove possible magnetic field generating objects around the weld.
11. In serious cases, use special degaussing equipment to degauss.
