The amount of argon gas required for MIG welding depends on the specific process being used and the type of metal being welded. In general, MIG welding typically requires a gas flow rate of 25 to 35 cubic feet per hour (cfh). This range is recommended for the commonly used short-circuit transfer mode in MIG welding.
The short-circuit transfer mode is characterized by the wire electrode making contact with the base metal, causing a short circuit and creating a small droplet of molten metal. This transfer mode is commonly used for welding thinner materials, such as sheet metal, and produces a relatively low heat input. The recommended gas flow rate of 25 to 35 cfh is sufficient to protect the weld pool from oxidation and ensure proper shielding.
TIG (Tungsten Inert Gas) welding, on the other hand, typically requires a lower gas flow rate compared to MIG welding. This is because TIG welding uses a non-consumable tungsten electrode and a separate filler material, if needed. The gas, usually pure argon, is used primarily to shield the weld area from atmospheric contamination. A flow rate of around 10 to 20 cfh is commonly used for TIG welding.
It’s important to note that the gas flow rate may vary depending on the specific welding equipment and settings being used, as well as the welding technique and personal preference of the welder. It is always recommended to consult the equipment manufacturer’s guidelines and adjust the gas flow rate accordingly.
In my personal experience as a welder, I have found that using the recommended gas flow rate for MIG welding ensures good weld quality and prevents issues such as porosity and lack of fusion. However, I have also encountered situations where higher gas flow rates were necessary, particularly when welding thicker materials or using a spray transfer mode. In such cases, gas flow rates slightly higher than 35 cfh may be used to provide adequate shielding and cooling.
To summarize, for MIG welding using the short-circuit transfer mode, a gas flow rate of 25 to 35 cfh is generally recommended. TIG welding typically requires a lower flow rate, usually around 10 to 20 cfh. It is important to consider the specific welding process, equipment, and materials being used when determining the appropriate gas flow rate. Always consult equipment guidelines and adjust the flow rate as needed to ensure proper shielding and weld quality.