What is arc pick welding?
When the first molten pool is formed, the electrode is picked up, but the arc is not extinguished. After the molten pool solidifies, the electrode is guided to the top of the first molten pool to spot weld the second molten pool. Then the electrode is picked up again, and so on. Arc pick welding is generally used for vertical welds with thinner welding materials or wider welds.
Technical features
The arc pick method has a relatively simple action, which is mainly to strengthen the control of the root gap during the positioning welding of the weldment. During the base welding process, the electrode does not swing, but only moves up and down, and the action is relatively simple.
Xinfa welding equipment has the characteristics of high quality and low price. For details, please visit: Welding & Cutting Manufacturers – China Welding & Cutting Factory & Suppliers (xinfatools.com)
Notes
(1) During the spot welding process of the welding test plate, the gap between the two ends should be strictly controlled. The size of the gap directly affects the quality of the back-side forming of the arc pick-up method.
(2) Spot welding should be performed within 20mm at both ends of the welding test plate. The gap should be 1mm larger than the gap at the other end than the starting end. Taking the 2.5mm electrode for base welding as an example, 3.5mm should be left on one side of the gap between the two ends of the welding test plate (the diameter of the 2.5mm electrode with the coating is 3.5mm), and 4.5mm should be left on the other side.
(3) After the positioning welds on both sides of the welding test plate are completed, the welding reinforcement should be performed within 20mm at both ends of the welding test plate to prevent the gap from being reduced due to the shrinkage of the positioning welds during the base welding process, which will affect the quality of the base welding.
(4) When making the base, pay attention to striking the arc at the positioning weld point. After striking the arc, preheat the positioning weld point and pull the arc to the edge of the positioning weld point for welding. Press down the arc to form a relatively uniform “melt hole” on both sides of the groove of the welding test plate. When the “melt hole” is formed, immediately lift the arc and break the arc. Then, according to this method, start and break the arc rhythmically to control the temperature of the molten pool and obtain a good reverse weld formation.
(5) Welding rod movement technique: no swing, only downward pressing and lifting movements. When the arc is struck at the first point, the angle of the welding rod is 15°~20° with the test plate. The angle of the welding rod for subsequent arcs is 30°~40° with the test plate. Note that the arc is broken by the wrist.
(6) During the welding process, the formation and size of the melt hole must be accurately controlled. The two sides of the melt hole must be consistent. The arc should completely melt the blunt edges on both sides of the groove and accurately penetrate 0.5~1.0mm into the parent material on each side.
(7) Pay attention to the rhythm and the overlap position of the welds. Each new weld should overlap the previous weld by 2/3. Keep 1/3 of the arc burning on the back of the test plate to heat and penetrate the blunt edge of the root of the groove to form a new weld.
Post time: Nov-04-2024
