How to Adjust the Parameters in CO2 Welding

Adjustment of process parameters for carbon dioxide gas shielded welding: There are many process parameters that affect carbon dioxide gas shielded welding, but the only ones that welders can adjust themselves are welding voltage, welding current, wire diameter, gas flow rate, and wire extension length; Reference values for welding process parameters: The commonly used wire diameters are 1.2mm and 1.0mm, in addition to 1.6mm and 0.8mm. It is difficult to encounter welding wires of other diameters. Carbon dioxide gas shielded welding adopts short-circuit transition, so the welding specification zone for each diameter of welding wire is wide. In this zone, the welding current and welding voltage must be matched。

    The operating procedure for adjusting welding specifications: Adjust the current and voltage of the welding machine according to the following procedure;

1. Open the protective gas cylinder valve and confirm that the gas cylinder pressure is normal; Turn on the welding machine power and confirm that the heating and pressure reducing flowmeter is working; Heat for 5 minutes;
2. Open the packaging of the welding wire, install the welding wire reel on the reel shaft of the wire feeding mechanism, open the clamping handle, and use pliers to cut the welding wire head into a flat head. The welding wire head should be horizontally inserted into the groove wheel of the wire feeding roller from below the welding wire reel; Insert the wire feeding hose;
3. Close the clamping handle, lay the welding gun flat on the ground and fully extend it. Press the white quick wire feeding button on the remote control box to feed the welding wire until it is exposed from the conductive nozzle. If it is an old welding gun, you can first remove the conductive nozzle, then press the micro switch to feed the wire, expose it, and then reinstall it; Use pliers to cut the end of the welding wire into a 45 degree sharp angle;

    4.Prepare the test steel plate, visually check the voltmeter and ammeter of the welding machine, consciously lower the           voltage on the remote control box with your left hand, hold the welding gun with your right hand, and initiate arc              welding on the test steel plate; If the voltage is indeed low, the right hand holding the gun will feel the strong      vibration of the welding gun head and hear the sound of the arc popping. This is the sound made when the voltage is too low, the wire feeding speed is much faster than the melting speed, and the arc is ignited and then extinguished by the welding wire; If the voltage is actually too high, the arc can ignite, but if the arc length is too long, a huge molten ball will form at the end of the welding wire. If the melting speed exceeds the wire feeding speed too much, the arc will continue to burn back to the conductive nozzle, melting the welding wire and the conductive nozzle together, terminating the wire feeding, and extinguishing the arc. This will cause damage to both the conductive nozzle and the wire feeding mechanism, so it should be confirmed that the voltage is not too high when starting the arc;

5. Adjust the welding voltage knob, gradually increase the welding voltage, accelerate the melting speed of thewelding wire, and the cracking sound of the breakage gradually becomes a smooth rustling sound;
6. Observe the voltmeter and ammeter. If the current is lower than the predetermined value, increase the welding current first and then increase the welding voltage; If the current is higher than the predetermined value, first reduce the welding voltage, and then reduce the welding current;
7. Extension length of welding wire: also known as dry extension length of welding wire. For gas shielded welding, it is a very important parameter. The appropriate extension length of the welding wire can provide sufficient resistance heating, making it easier to form and transition molten droplets at the end of the welding wire. When the extension length of the welding wire is too short, there is often a lot of splashing. Being too long not only easily produces splashing of large droplets, but also leads to poor protection.
8. Phenomenon when welding voltage and welding current are matched: the arc burns steadily, making a fine rustling sound, the welding gun head vibrates slightly, the hardness is moderate, the voltmeter swing does not exceed 5V, the ammeter swing does not exceed 30A, and there should be no vibration at the grip of the hand; If the head of the welding gun feels too soft and there is almost no vibration, the welding gun can be moved freely. Through the face mask observation, the welding wire floats above the molten pool, forming a large molten ball at the end, and sometimes large droplets splash, indicating that the voltage is too high; If the head of the welding gun feels hard and vibrates significantly, a popping sound can be heard, and there is resistance when moving the welding gun. Through the face mask observation, if the welding wire is inserted into the molten pool and splashes more, it indicates that the voltage is low; It is advantageous to have a slightly higher voltage to prevent incomplete fusion.
9. Gas shielded welding with melting electrode, the adjustment of welding current is to adjust the wire feeding speed of the welding wire, and the adjustment of welding voltage is to adjust the melting speed of the welding wire. When the wire feeding speed and melting speed are equal, the arc burns stably.