There are different types of welding processes in the world. Among them, MIG welding is a process that produces perfect weld without any damage to the material. The MIG welding is also known as metal inert gas welding or metal active gas welding. The other name of MIG welding is gas metal arc welding. In this welding, the electric arc is formed between a consumable wire electrode and the base metal. This electric arc heats and melts the base metal and joins it. To safeguard the metal from the atmospheric oxygen and nitrogen, gasses such as carbon dioxide is used in this method. This article explains the process of MIG welding.
What are the types of equipment used?
Before explaining the process, it is necessary to learn about the equipment in MIG welding. The various equipment used in MIG welding are as follows.
Welding gun and wire feed unit
The welding gun used in the MIG welding process consists of many key parts; they are, control switch, power cable, contact tip, gas nozzle and a gas hose. The control switch is used to trigger the operation. The contact tip is made up of copper and is connected to the welding power source through the welding cable. The gas nozzle is used to direct the shielding gas.
The most common power supply used in the type of welding process is the constant DC voltage power supply. This power supply will maintain a constant power when the electric arc is placed near the base metal. The alternating current power supply can also be used in this process but it is less preferred.
The main feature of MIG welding process is the use of the solid electrode. This method uses all commercial electrodes, that contain deoxidizing agents such as silicon, aluminum etc. are used because it does not have oxygen polarity.
The shielding gas is used to protect the weld from the oxides of nitrogen and oxygen in the atmosphere. The commonly used shielding gas in this type is the carbon dioxide. Various other shielding gasses such as argon and argon helium gasses can be used in this. The shielding gasses are preferred based on the type of electrode used.
The process of MIG welding is very simple. The electrode is fed automatically with the torch. The operation by the welder is very less compared to the TIC welding. In this process, the job of the operator is to handle the welding gun in the proper position to obtain a fine weld. The electric spark arises from the gun and melts the electrode and the base metal and unites them. To obtain perfect welding the gun should be placed in the correct angle position. This method is also referred as the semi-automatic welding process since the electrode is fed automatically.
- All position capability.
- Higher deposition rate.
- Less post welding cleaning.
- A Long weld can be made.
- Used in thin metals.
- Used in pipe joints.
- Commonly used in industries.
The only drawback is the cost, other than that this technique is the best technique used to form a good weld.