Robotic arc welding has grown as an industry only recently, but is quickly catching up to spot welding as the most popular robotic welding method. The process uses a power supply to generate an electric arc between a torch-mounted electrode and metal. This arc produces a temperature of about 6,500 degrees Fahrenheit at the tip of the torch. This heats up the metal, producing a pool of molten metal beneath the torch that solidifies upon cooling. Upon cooling, the parts permanently fuse together.
Because of the extremely high temperatures produced, the metals involved in this process will often react chemically with the oxygen and nitrogen in the surrounding air. This can compromise the integrity of the weld joint. For this reason, many arc-welding processes involve a process called arc shielding. This process covers the arc and the molten metal with a protective shield of gas or vapor, minimizing the contact between the molten metal and the surrounding air.
The extreme heat and chemical reactions involved in arc welding make it a perfect application for robotics, as this reduces the exposure of workers and operators to these risks.