Cover, the edge of the groove should be a little pause to ensure that the molten pool and groove better fusion, the welding process of the welding arm of the swing amplitude and frequency to adapt to ensure that the cover surface weld surface size and edge fusion neat. Welding, the torch angle to the vertical axis with the tube, because the tube is round, so the angle of the torch to change at any time, so as to ensure the quality of the weld to avoid the pores of the weld, slag and so on. When the cover is welded, pay attention to whether the nozzle and the contact nozzle are clean, the size of the gas flow is appropriate, clean the bottom surface, and control the inter-layer temperature.
Wire feed, remove the frequency faster than the solid wire. Due to filling, cover layer with gas shielded welding, wire length of the length of the welding process on the stability of the greater impact of the longer wire length, wire resistance increases, the wire overheating and melting, the results of the welding process unstable welding, metal splash serious, poor weld formation, the protection of the molten pool is not good; wire length is too short, the welding current increases, the distance between the nozzle and the workpiece to shorten the welding line of sight is unclear, while also causing the nozzle to overheat, causing the splash to stick or clog the nozzle, thereby affecting the gas flow. Such as found crater cracks, shrinkage and other defects, should be cleaned and then welded.In the process of MAG welding, the length of the welding wire is 8 ~ 9mm, the amplitude, frequency, speed and edge residence time of the welding torch are coordinated with the appropriate action, and the angle of the welding torch is adjusted at any time to make the edge of the weld surface neatly and beautifully to ensure the quality of filling and cover layer.