Technical Tips
How to choose welding gas – Coregas brand
How to choose the right welding gas for your application
Many common welding processes such as MIG, TIG and Metal-Core Arc Welding all require an external shielding gas to function correctly.
A shielding gas essentially protects a weld from exposure to nitrogen, oxygen and hydrogen present in the atmosphere.
These elements can react with the weld pool and cause issues such as porosity and excessive spatter.
The Shielding Gas Solutions Guide below offers a basic overview of the welding process, materials and the suitable shielding gases for each application
| Material | Shielding gas | Composition | Process | Features and Benefits |
| Carbon steel | Coregas 5/2 | Ar-CO2-O2 | GMAW | Up to 8mm. Dip transfer, minimal spatter, good control when positional welding. |
| Carbon steel | Coregas 07 | Ar-O2 | GMAW | Up to 6mm. Minimal spatter, good weld profile, reduced penetration. Smooth running. Not good for out of position. Good for galvanise |
| Carbon steel | Coregas 10 | Ar-CO2 | GMAW | All thicknesses. Good arc transfer, smooth appearance, little spatter. Good for robotic welding. |
| Carbon steel | Coregas 16/3 | Ar-CO2-O2 | GMAW | 12mm and above. Dip and spray transfer, good penetration profile and smooth running. |
| Carbon steel | Coregas 18 | Ar-CO2 | GMAW–FCAW | Heavy section material. Spray transfer. Also FCAW carbon and stainless steel. Improved working environment and easy to set the working point |
| Carbon steel | Coregas 25 | Ar-CO2 | GMAW–FCAW | Heavy section material. Mainly intended for short arc welding with less risk of porosity when plates are dirty, oily or having mill scale. Also spray transfer, FCAW carbon and stainless steel. |
| Carbon steel | Coregas He 30 | Ar-HE-CO | GMAW | High deposition rates. Good weld profile and penetration. Mainly for automation and good for heavier sections of galvanised material. |
| Carbon steel | Carbon Dioxide | CO2 | GMAW–FCAW | Up to 10mm. Dip transfer only. Increased spatter levels. Also for some FCAW applications. |
| Carbon steel | Argon | Ar | GTAW | All thicknesses. |
| Stainless steel | Shieldpro 20 | Ar-CO2 | GMAW | All thicknesses. Dip and spray transfer, minimal oxidation. Excellent for pulsed MAG. Good penetration and flat weld bead. Improved working environment. |
| Stainless steel | Shieldpro 21 | Ar-O2 | GMAW | Up to 3mm. Dip transfer. Reduced penetration and smooth running. |
| Stainless steel | Shieldpro 22 | Ar-H2 | GTAW | Hydrogen addition gives higher welding speed due to hotter and more constricted arc. 2mm and above. Austenitic stainless steels only. Increased deposition rates. Reduced oxides. Improved weld profile. |
| Stainless steel | Shieldpro 23 | Ar-N2 | GTAW | The Nitrogen addition reduces Nitrogen loss from the weld metal resulting in better corrosion properties compared to welding with pure Argon. Mainly for orbital TIG welding. Increased pitting corrosion resistance. |
| Stainless steel | Shieldpro 30 | Ar-HE-CO2 | GMAW | All-round gas for stainless steels and duplex. 3mm and above. Good deposition rates and weld profile. Increased penetration and fluidity of the weld pool. Higher welding speed compared to gases without Helium. |
| Stainless steel | Shieldpro 31 | Ar-HE-CO2 | GMAW | All thicknesses. Good deposition rates, weld profile and smooth surface appearance. |
| Stainless steel | Shieldpro 32 | Ar-HE-CO2 | GMAW | Over 6mm. Good deposition rates and weld profile. |
| Stainless steel | Shieldpro 33 | Ar-HE-O2 | GMAW | Over 3mm stainless steel and Duplex. Good deposition rates and weld profile. Reduced spatter. good edge wetting. |
| Stainless steel | Argon | Ar | GTAW | All thicknesses. Most commonly used. |
| Non-ferrous | Shieldpro He 25 | Ar-HE | GMAW–GTAW | Over 3mm. Good deposition rates and weld profile. |
| Non-ferrous | Shieldpro He 50 | Ar-HE | GMAW–GTAW | Over 3mm. Good deposition rates and weld profile. |
| Non-ferrous | Shieldpro He 75 | Ar-HE | GMAW | Above 6mm. Good deposition rates and weld profile. Smooth arc characteristics, rotate, clean, smooth surface appearance. |
| Non-ferrous | Argon | Ar | GMAW–GTAW | Below 3mm. Acceptable deposition rates and weld profile. |
| Copper and alloys | Shieldpro He 25 | Ar-HE | GMAW–GTAW | Above 3mm. Good deposition rates and weld profile. |
| Copper and alloys | Argon | Ar | GMAW–GTAW | Below 3mm. Acceptable deposition rates and weld profile. |
| Nickel and alloys | Shieldpro 22 | Ar-H2 | GTAW | 2mm and above. Increased deposition rates. Reduced oxides. Improved weld profile |
| Nickel and alloys | Argon | Ar | GMAW–GTAW | Below 3mm. Acceptable deposition rates and weld profile. |
The above recommendations are only a basic guide. For the most accurate recommendation several other aspects must be considered including wire diameter, the setting of parameters and welding position.
If you need to order gas, please order at COREGAS DEPOT – ALL WELDING & ELECTRICAL SUPPLIES
When you need more information, please contact All Welding & Electrical Supplies at email: info@allwelding.com.au or phone number: 1300 255 935.