First- Material selection
Welding wire: TWLQ3501 φ1.6
Second. Preparation before welding
- Remove oil, rust, water and defects (such as cracks, pits, etc.) on the surface of the material.
- Preheating before welding: heat preservation at 250-300°C for 8 hours (the principle is to fully preheat the material. Preheating can be carried out according to the power of the electric furnace and the quality of the material).
Third-Welding process parameters
- Welding current: I=260-320A Voltage: U=30-33V
- Dry elongation: 15-20mm
- Welding speed: swing welding 100-130mm/min
- Overlapping amount: 3-5mm
- interval temperature: 250-300°C
- Gas flow rate: 15-25L/min
- Torch angle: 70-90 degrees
- Left and right retention: 0.1-0.5s
- Welding gas: mixed gas (80%Ar+20%CO2)
Single layer thickness 2.5-3.0mm. Weldable thickness can be selected according to the welding thickness.
Fifth- Post-welding treatment
- Put it into the furnace at 250-300℃ after welding, and cool slowly in the furnace.
- Lower the temperature below 100°C and take out the oven.
- Process the required thickness.
Sixth-Other matters needing attention
- Ensure sufficient preheating before welding.
- Pay attention to the control of the interval temperature during the welding process.
- The stem length is between 15-20mm.
- Check whether the gas protection cover is blocked, and clean it in time. If the protection is not good, it will cause air holes.
- The angle between the welding torch and the welding surface is 70-90 degrees. If the angle is too low, the gas will be blown away, the protection will be poor, and air holes will be generated.
- Store the welding wire in a cool and dry place and use it up within three days after opening the package.
- Avoid the welding wire from getting wet. After getting wet, it needs to be baked at 250°C for more than 2 hours.
- When the gas flow rate is 15-25L/min and the air pressure is lower than 1Mpa, it is no longer used, and it is easy to vent.