Key Points And Precautions for Stainless Steel Welding

1. Use a power supply with vertical external characteristics, and use positive polarity for DC (welding wire is connected to the negative pole)
2. Generally suitable for welding thin plates below 6mm, with beautiful weld shape and small welding deformation characteristics.
3. The protective gas is argon with a purity of 99.99%. When the welding current is 50^150, the argon gas flow is 8.10L/min. When the current is 150^~250, the argon gas flow is 12.15L/min.
4. The length of the tungsten electrode protruding from the gas nozzle is preferably 4-5mm. In places with poor shielding such as fillet welding, it is 2-3m. In places with deep grooves, it is 5-6mm. The distance from the nozzle to the work is generally not more than 15mm.
5. To prevent the occurrence of welding pores, any rust, oil stains, etc. on the welding part must be cleaned.
6. The welding arc length is preferably 2~4mm when welding ordinary steel, and 1~3mm when welding stainless steel. If it is too long, the protection effect will be poor.
7. During butt bonding, to prevent the back side of the bottom weld bead from being oxidized, the back side also needs to be protected by gas.
8. For the argon gas to protect the weld pool well and facilitate the welding operation, the center line of the tungsten electrode and the workpiece at the welding location should generally maintain an angle of 80^85°, and the angle between the filler wire and the surface of the workpiece should be as small as possible. , generally around 10°.
9. Windproof and ventilated. In windy areas, be sure to take measures to block nets, and take appropriate ventilation measures indoors.

Key points and precautions for MIG welding of stainless steel
1. Use a flat characteristic welding power source, and use reverse polarity for DC (welding wire is connected to the positive electrode)
2. Generally, pure argon (purity 99. 99%) or Ar+2% 02 is used, and the flow rate is 20-25L/min.
3. Arc length. MIG welding of stainless steel is generally welded under spray transition conditions, and the voltage should be adjusted to an arc length of 46mm.
4. Windproof. MIG welding is easily affected by wind, and sometimes, the breeze can cause pores. Therefore, wind protection measures should be taken wherever the wind speed is above 0.5m/sec.
Key points and precautions for stainless steel flux cored wire welding
1. Use a flat characteristic welding power source, and use reverse polarity during DC welding. You can use an ordinary C02 welder to weld, but please loosen the pressure on the wire feed wheel slightly.
2. The protective gas is generally carbon dioxide, and the gas flow rate is 20-25L/min.
3. The appropriate distance between the welding tip and the workpiece is 15-25m.
4. Dry extension length, the general welding current is about 15mm when the welding current is below 250A, and about 20-25m when the welding current is above 250A is more suitable.