MIG Wire Welding Precautions

When Ar+CO, or Ar+O2 mixed gas is used for welding, the change in gas ratio has a great impact on the welding process and the mechanical properties of the weld, and a stable gas ratio should be ensured.

 

1. The reduction of gas activity will lead to increased sensitivity to impurities such as oil, rust, and water, so the rust, oil, water and other impurities on the surface of the groove should be strictly removed before welding, otherwise it will be extremely unfavorable to the welding process performance and the mechanical properties of the weld, which is an important part of ensuring the excellent mechanical properties of the weld;

 

2. When Ar+CO, or Ar+O2 mixed gas is used for welding, the change in gas ratio has a great impact on the welding process and the mechanical properties of the weld, and a stable gas ratio should be ensured;

 

3. Although the increase of the length of the welding wire (dry elongation) can improve the welding deposition rate, it will deteriorate the welding process and weld performance, such as increased spatter, weld corrugation and rough forming, and increased porosity sensitivity. It is recommended that when the welding current is lower than 250A, the length of the welding wire is about 10~18mm; When the welding current is greater than 250A, the length of the welding wire is between 20~25mm.

 

High Quality Stainless Steel Welding Wire

 

4. The flow rate of shielding gas should be controlled between 15~20L/min; Too low will cause air to infiltrate, too high will create turbulence.

 

5. In order to make the arc pit not affect the safety and reliability of the whole weldment, the arc pit can be filled by using methods such as the welding torch pausing in place for a few seconds after arc extinguishing, intermittent arc ignition, and moving back arc;

 

6. The influence of wind should be avoided during the welding process, and wind blocking measures should be used when the wind speed ≥ 1.8m/s or high-rise welding; It should not be directly blown by the fan at the weld place;

 

7. The workplace should adopt ventilation measures, especially in the relatively closed and poor ventilation occasions, so as to minimize the personal injury to the welding personnel;

 

8. When Ar+CO, or Ar+0, mixed gas is used for welding, the current has a critical value, below this current, the metal is generally transitioned by coarse melt droplets larger than the diameter of the welding wire, and the spatter is larger; Above this current, a high droplet formation rate will occur suddenly, forming a jet transition; For this type of welding, the arc is unstable and AC welding is not recommended;

 

9. During the welding process, the welding torch is inclined to the side of the weld to reduce the penetration depth, which is beneficial to the welding of thin plates.