Argon arc welding operation method
Argon arc is an operation in which the left and right hands move at the same time, which is the same as drawing circles with the left hand and drawing squares with the right hand in our daily life. Therefore, it is recommended that those who have just started to learn argon arc welding have similar training, which will be helpful to learn argon arc welding.
(1) Wire feeding: divided into inner wire filling and outer wire filling.
The outer filler wire can be used for priming and filling. It uses a large current. The welding wire head is on the front of the groove. The left hand pinches the welding wire and continuously sends it into the molten pool for welding. The groove gap requires small or no gap.
Its advantages are high production efficiency and easy operation skills due to the large current and small gap. Its disadvantage is that if it is used for bottoming, because the operator cannot see the melting of the blunt edge and the reinforcement of the reverse side, it is easy to produce unfused and not get the ideal reverse forming.
The inner filler wire can only be used for backing welding. Use the thumb, index finger or middle finger of your left hand to coordinate the wire feeding action. The little finger and ring finger clamp the welding wire to control the direction. The welding wire is close to the blunt edge inside the groove and melts together with the blunt edge For welding, the groove gap is required to be larger than the diameter of the welding wire. If it is a plate, the welding wire can be bent into an arc.
Its advantage is that because the welding wire is on the opposite side of the groove, the blunt edge and the melting condition of the welding wire can be clearly seen, and the reverse reinforcement can be seen from the peripheral vision of the eyes, so the weld fusion is good, and the reverse reinforcement and non-fusion can be obtained good control. The disadvantage is that the operation is difficult, and the welder is required to have more skilled operation skills. Because the gap is large, the welding volume will increase accordingly. The gap is large, so the current is low, and the work efficiency is slower than that of external filler wire.
(2) Welding handles are divided into crank handles and mops.
The shaking handle is to press the welding nozzle slightly on the welding seam, and shake the arm greatly to weld. Its advantages are because the welding nozzle is pressed on the weld seam, and the welding handle is very stable during operation, so the weld seam is well protected, the quality is good, the appearance is very beautiful, and the product qualification rate is high. Gets a very nice looking color. The disadvantage is that it is difficult to learn, because the arm shakes a lot, so it is impossible to weld at obstacles.
The mop means that the welding tip leans lightly on or does not lean on the weld seam, the little finger or ring finger of the right hand also leans on or does not lean on the workpiece, the arm swings small, and drags the welding handle for welding. Its advantage is that it is easy to learn and has good adaptability. Its disadvantage is that the shape and quality are not shaken well, especially for overhead welding without a shaker to facilitate welding. It is difficult to obtain ideal color and shape when welding stainless steel.
(3) Arc ignition: Arc ignition is generally used (high-frequency oscillator or high-frequency pulse generator), and the tungsten electrode and the weldment do not contact to ignite the arc. When there is no arc ignition, contact arc ignition is used (mostly used in construction sites) installation, especially high-altitude installation), copper or graphite can be placed on the groove of the weldment to strike the arc, but this method is more troublesome and less used. Generally, a light stroke with a welding wire makes the weldment and the tungsten electrode directly short-circuited and quickly disconnected. And ignite the arc.
(4) Welding: After the arc is ignited, it is necessary to preheat for 3-5 seconds at the beginning of the weldment, and start wire feeding after the molten pool is formed. When welding, the angle of the welding wire torch should be appropriate, and the welding wire should be fed evenly. The welding torch should move forward smoothly, swing left and right slightly slower on both sides, and slightly faster in the middle. Pay close attention to the changes of the molten pool. When the molten pool becomes larger, the weld seam becomes wider, or the welding seam becomes concave, the welding speed should be increased or the welding current should be reduced again. When the fusion of the molten pool is not good and the wire cannot be fed, it is necessary to reduce the welding speed or increase the welding current. If it is bottom welding, the eyes should focus on the blunt edges on both sides of the groove, and the corners of the eyes. Peripheral light is on the opposite side of the slit, and pay attention to the change of other heights.
5) Arc extinguishing: If the arc is extinguished directly, it is easy to produce shrinkage cavity. If the welding torch has an arc starter, the arc should be closed intermittently or adjusted to an appropriate arc crater current. The arc is led to one side of the groove, and no shrinkage hole is formed. If the shrinkage hole occurs, it must be polished before welding.
If the arc is at the joint, the joint should be ground into a bevel first, and then welded forward 10-20mm after the joint is fully melted, and then the arc is closed slowly, and no shrinkage cavity can occur. In production, it is often seen that the joints are not polished into bevels, and the welding time of the joints is directly lengthened for joints. This is a very bad habit. In this way, the joints are prone to concave, joints that are not fused and the reverse side is out of joint, which will affect the appearance of the shape. If it is a high alloy The material is also prone to cracks.
Post time: Mar-15-2023
