Local melting forms a molten pool. At the same time, CO2 gas sent from the gas cylinder is ejected from the nozzle of the welding torch at a certain pressure and flow rate, thus forming protection.
The operation of vertical fillet welding is the same as vertical butt welding. In order to master the operation skills of vertical angle welding, we should also pay attention to the following links.
(1) welding current. Under the same conditions as butt welding, the welding current can be slightly larger to ensure the penetration.
(2) The location of covered electrode. In order to make the two weldments heated evenly, ensure the penetration and improve the efficiency, attention should be paid to the position and inclination of covered electrode.
(3) Control of molten metal. In the welding process, when the first melting occurs after arc initiation, the arc should be raised quickly.
(4) covered electrode's swing. According to the requirements of plate thickness and weld leg size, choose the appropriate strip conveying mode. For welds with small butt weld legs, straight reciprocating belt feeding can be adopted; When the size of the welding leg is required, crescent, triangle, sawtooth and other methods can be used. In order to avoid defects such as undercut, in addition to selecting appropriate current, covered electrode should stay on both sides of the weld for a period of time to make molten metal fill the edge parts on both sides of the weld.
Extended data:
Flat welding, serrated bar transportation. Vertical welding, triangular transportation. Other cloud banding methods are rarely used. To know the size of the fillet to be welded, first burn a standard fillet according to the size of the fillet. Note that high quality welding must be from bottom to top!
Start the arc ignition at the standard welding angle, and be careful not to exceed the molten pool when the welding wire swings left and right.
When the welding wire is completely dissolved, both sides pause when swinging left and right, and the length of time depends on the welding angle. If the welding angle is too large, it is recommended to weld several times. Generally, it is easier to weld under small points for the first time. If it is too big at one time, it is easy to be ugly and ugly, and both sides are easy to bulge.
When swinging from side to side, it is necessary to control the rhythm, weld slowly upward, and pay attention to the stability of both hands, which is a necessary prerequisite for high-quality welding.
Baidu Encyclopedia -CO2 gas shielded welding