MIG welding (metal welding with inert gases) is a so-called arc welding process.
The welding wire (2) is continuously and automatically unwound from a coil by means of a motor at a variably adjustable speed. The wire is led directly and directly to the welding point using the contact sleeve (1). The welding wire melts off immediately. During the MIG welding process, shielding gas (3) is fed through a nozzle. This prevents the penetration of oxygen into the weld pool (4) and thus protects against oxidation. This would weaken the weld seam and consequently lead to inferior quality. The finished weld seam is also called a weld bead (5).
While MIG welding works with active gases and steel is primarily connected, MIG welding uses non-ferrous metals to weld inert gases. Argon is used as the inert gas, in rare cases also helium (which is more expensive) or their mixtures. Since the gases used do not react with the base and filler materials, MIG welding is mainly used to connect copper, aluminum or aluminum alloys and other non-ferrous metals.
The inert gases allow welding at much higher temperatures. The possibility of oxidation of the weld seam occurring is thus excluded, which in turn has a very advantageous effect. Because of weather influences such as If the shielding gas is driven away, MIG welding can only take place in closed rooms. The welding process outdoors would therefore take place without the useful oxidation protection and thus a weld seam of inferior quality would result, which would be much more sensitive to rust and not as stable.
This type of welding is used to manufacture tanks and pipes, in mechanical engineering, in precision engineering or in nuclear technology.
Differentiation between different arcs in MIG welding
The welding wire (2) is continuously and automatically unwound from a coil by means of a motor at a variably adjustable speed. The wire is led directly and directly to the welding point using the contact sleeve (1). The welding wire melts off immediately. During the MIG welding process, shielding gas (3) is fed through a nozzle. This prevents the penetration of oxygen into the weld pool (4) and thus protects against oxidation. This would weaken the weld seam and consequently lead to inferior quality. The finished weld seam is also called a weld bead (5).
While MIG welding works with active gases and steel is primarily connected, MIG welding uses non-ferrous metals to weld inert gases. Argon is used as the inert gas, in rare cases also helium (which is more expensive) or their mixtures. Since the gases used do not react with the base and filler materials, MIG welding is mainly used to connect copper, aluminum or aluminum alloys and other non-ferrous metals.
The inert gases allow welding at much higher temperatures. The possibility of oxidation of the weld seam occurring is thus excluded, which in turn has a very advantageous effect. Because of weather influences such as If the shielding gas is driven away, MIG welding can only take place in closed rooms. The welding process outdoors would therefore take place without the useful oxidation protection and thus a weld seam of inferior quality would result, which would be much more sensitive to rust and not as stable.
This type of welding is used to manufacture tanks and pipes, in mechanical engineering, in precision engineering or in nuclear technology.
Differentiation between different arcs in MIG welding
- Short arc welding
- Spray arc welding
Rather thicker sheets are connected here. The low-splash, fine-droplet and short-circuit-free material transfer results from the large melting and high speeds when welding with argon mixed gases.
- Pulse arc welding
This type of arc welding is used for all sheet thicknesses. It is welded with argon-rich mixed gases. This welding process is used in the medium performance range. Here, a pulse current is placed over the base current. It is possible to regulate the thickness of the droplets generated during welding as required. This results in a short-circuit-free, with minimal formation of splashes and even, fine-droplet transition of the materials.
Advantages of MIG welding:
No slag is produced in MIG welding. The shielding gas shields the weld seam from the influence of oxygen and therefore prevents the risk of oxidation. Due to the high pace of work, the materials to be welded have less heat. Only slight deformations are to be expected. This welding process is also the best method because of the possibility of welding in constrained positions. It became the most widely used welding process. The high strength of the weld seam reduces the intensity of the rework.
Disadvantages of this welding process:
If MIG welding were used outdoors, it would inevitably lead to the inert gases being blown away. Therefore, this gas metal arc welding can only be carried out in closed rooms. It is not easy to master and requires a lot of experience. Particular attention must be paid to thorough weld preparation.
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