Plasma Arc Welding:
Plasma Arc Welding (PAW) is a modification of TIG(GTAW) Welding Process. As Plasma is an intense source of heat, it is used to fuse metals in this process and increase productivity.
In PAW, as the electrode is placed within the body of the torch, plasma arc can be separated from the shielding gas. The plasma is then forced through a fine-bore copper nozzle, that compresses the arc and the plasma exits at very high velocity (approximately at the speed of sound) and a temperature approaching 28,000 °C (50,000 °F) or higher. Plasma is the temporary state of a gas. The gas gets ionized after passage of electric current through it and it becomes a conductor of electricity. In ionized state atoms break into electrons(-) and ions(+) and the system contains a mixture of ions, electrons and highly excited atoms. This high velocity of atoms and heat melts the metal and helps to fuse two metals.
Plasma being intense source of heat is used for joining metals. The shape of Plasma arc makes the process immune to variation of gap between the Plasma welding torch and the job. It is possible to weld 0.05mm thick materials with programmable micro plasma welding systems. Keyhole welding up to 6mm thick materials is quite common. Plasma-TIG process enhances productivity several folds. Plasma welding process is generally used with automation.
Types of Plasma Arc Welding Machine
Micro Plasma Welding Machines
Machines Capable to weld metal sheets of as thin as 100 microns to 1 mm.
Plasma Welding Machines
Machines capable to weld a wide range of very thin sheets ranging from 100 microns to 5 mm.