SOME CONCEPTS ABOUT WELDING TECHNOLOGY

Distinguishing Between MIG Welding and TIG Welding

MIG Weling

TIG Welding

Concept

MIG (MAG) Welding is a welding method that belongs to the GMAW (Gas Metal Arc Welding) group. It utilizes heat generated from an arc burning between a continuously fed solid electrode wire and the workpiece, with a constant wire feed speed provided by a wire feeder. The molten pool is protected by an inert gas (MIG) or an active gas (MAG).

This method is also referred to as semi-automatic welding, though this term is not entirely accurate. In industrial applications, MAG welding with CO₂ shielding gas is commonly known as wire welding or CO₂ welding.

TIG Welding (Tungsten Inert Gas Welding) is also known as non-consumable tungsten electrode arc welding in a shielding gas environment – GTAW (Gas Tungsten Arc Welding). It is commonly referred to as Argon welding or WIG (Wolfram Inert Gas Welding).

This method uses shielding gases such as Argon, Helium, Argon + Helium, Argon + Hydrogen, or Argon + Oxygen.

Character

- The electrode does not melt. No slag due to the absence of solder. Arcs, puddles are easy to observe and control. The centralized power supply has a high temperature. Thin or thick metals can be welded due to the wide range of welding parameters (from a few amperes to several hundred amperes).
- Welds most metals and alloys with high quality. The weld is clean and beautiful, without slag and splatter. Easy control of swallowing and welding pool shape.
- Use of Argon gas

Technique

- This method uses heat from an arc burning between a continuously fed solid electrode wire, supplied by a wire feeder at a constant speed. The molten pool is protected by an inert gas flow (MIG). This method is also called semi-automatic welding, but that name is not entirely accurate.

- To fill the welding arc into the area to be welded, we use a TIG welding setup consisting of a welding machine, shielding gas, power source, and welding torch… all connected in a standardized system. Once the system has been checked and is functioning properly, welding begins.The principle is as follows: Under the effect of electric current, a key component in the welding torch called the non-consumable electrode (tungsten electrode) generates an extremely high amount of heat. When the filler rod is added, it melts under the high heat and forms an arc that fills the weld joint.

Advantages

- CO2 is an easily obtainable gas, simple to produce, and low-cost. Welding productivity with CO2 is high, more than 2.5 times that of manual arc welding. The technological advantage of CO2 welding is greater than submerged arc welding because it can be performed in any spatial position.
- High welding quality. Welded products experience minimal distortion due to high welding speed, concentrated heat source, high thermal efficiency, and a narrow heat-affected zone. MIG welds are usually deep and aesthetically pleasing; if performed by a skilled welder, they can produce very clean and beautiful welds.
- Can weld various metals such as steel, stainless steel, and aluminum. Working conditions are better compared to manual arc welding, and no toxic gases are released during the welding process.

It can weld both thin and thick metals due to a wide adjustable welding parameter range (from a few amps to several hundred amps). It can weld metals and alloys with high quality. The weld is clean and aesthetically pleasing, without slag inclusion or spatter. The penetration depth and weld pool shape can be easily controlled. It can be performed with or without a filler rod to create the weld.

Disadvantages

- Low productivity.
- Requires highly skilled workers.
- Relatively high cost due to low productivity, expensive equipment and raw materials.

When to use MIG welding and when to use TIG welding?