1. use vertical external characteristic power supply, DC adopts positive polarity (wire to negative electrode).

2. generally suitable for welding below 6mm thin plate, with beautiful weld appearance and small welding deformation.

3. the protective gas is argon and the purity is 99.99%. When the welding current is 50-50A, the argon flow rate is 8-0L/min, and when the welding current is 50-250A, the argon flow rate is 2-5L/min.

4. The length of the tungsten pole protruding from the gas nozzle is 4-5mm, 2-3mm in the poor shielding areas such as fillet welding, 5-6mm in the depth of grooving, and the distance between the nozzle and the work is generally not more than 5mm.

5. in order to prevent the appearance of welding porosity, rust and oil stains must be cleaned up.

6. Welding arc length, welding ordinary steel, 2-4 mm is better, and welding stainless steel, 3 mm is better, too long is not good protection effect.

7. when the bottom is butted, the backside also needs gas protection to prevent the oxidation of the back side of the bottom bead.

8. In order to protect the weld pool well by argon gas and facilitate welding operation, the angle between the center line of tungsten electrode and the workpiece should be kept between 80 and 85 degrees, and the angle between the filler wire and the workpiece surface should be as small as possible, generally about 0 degrees.

9. windbreak and ventilation. In the windy area, please take the measures of blocking the net, while indoors, it is necessary to take appropriate ventilation measures.