What is plasma welding?
To understand this term, you need to understand what plasma is. Ionized gas, which consists of neutral atoms and electrically charged nuclei and electrons, is called plasma. To date, this type of welding is considered to be the most qualitative and progressive. It is widely used in all spheres of industry.
This method can be used for soldering, for welding refractory sheet metals up to 1 mm thick, for welding metals with non-metals, for cutting. Since a welding machine is used, the plasma of which has a very high temperature and a wide range of technological properties, this type of welding has a number of advantages over other technologies.
Plasma welding equipment
Plasma welding is characterized by increased productivity, higher stability of arc burning, small zone of thermal influence, lower deformation during welding, and lowered consumption of shielding gases. Equipment for plasma welding is much more compact, which significantly increases the mobility and speed of welding. The presence of hydrogen in the plasma jet improves the quality of the weld, but at the same time, hydrogen is extremely explosive.
The welding torch has a reduced nozzle life due to the high thermal conductivity of the arc. This, perhaps, all the shortcomings. The device for plasma welding can be of two types: with an arc of direct action and indirect. Since the plasma arc of the direct-acting device has a cylindrical shape and is combined with the jet column, such devices are characterized by increased thermal power and arc temperature, as well as a more efficient cooling system.
The efficiency of such plasmatrons is much higher than for devices with an arc of indirect action, by attracting additional heat during welding by means of an electric current. Because of this, such devices should be used for cutting, welding, surfacing, and devices with an arc of indirect effect - for heating or spraying.
Modern view on welding
The research on the use of low-amperage arcs for welding has led to the development of microplasma welding technology. It uses low-amperage currents that burn in the pulsed mode and is used to weld thin-sheet materials. The microplasma welding machine uses a tungsten electrode, which is designed for low-current currents, which is characterized by low heat release, and the metal is not burnt. In this way, you can weld sheets of copper, titanium, tantalum, molybdenum and even gold with a thickness of 0.03-0.8 mm.
Such welding technology is used in nuclear, gas, medical, electronic and other industries. Apparently, this technology and will be almost the only way to join sheet metal in the next few decades.
The technology of the welding described is associated with a special risk of electric shock to high voltage, which can lead to muscle spasms and cardiac arrest. To avoid this, you should wear protective clothing and observe safety rules. The welding machine must not have any insulation defects. During welding, very bright light appears, therefore, to protect the eyes, a protective shield must be worn.