The heat generated by arc discharge (commonly known as […]
The heat generated by arc discharge (commonly known as arc burning) melts the electrode and the workpiece and forms a weld after condensation to obtain a welding process of a strong joint. The electric arc is used as a heat source, and the physical phenomenon of air discharge is used to convert electrical energy into heat energy and mechanical energy required for welding, so as to achieve the purpose of connecting metals.
The strongest self-sustained discharge in gas discharge. When the power supply provides more power, if the voltage between the poles is not high (about tens of volts), the gas or metal vapor between the poles can continue to pass a strong current (several amperes to tens of amperes) and emit a strong Brilliant, produce high temperature (thousands to tens of thousands of degrees), this is the arc discharge. Arc is a common thermal plasma (see plasma applications).
Because the voltage of the welding machine is relatively low, the voltage of the welding machine is about 50 volts when no-load, and the voltage of the welding machine is about 25 volts when welding. Compared with the voltage of more than 50 volts, the resistance of the dry skin of the human body is relatively large, and the voltage will not penetrate the skin, so it will not charge people.
“A group of welding processes producing coalescence of work pieces by melting them with an arc. The processes are used with or without the application of pressure and with or without filler metal” - Definition given by American Welding society (AWS).
As by the definition arc which is terminated by electrode is used to melt the work pieces. It is possible by excess heat generation.
Arc is nothing but the intense heat which is generated when the electric current passes through the high resistance air gap .
Arc Welding includes
1. AC or DC bare welding
3. TIG welding
The below figure shows the DC arc welding set-up in which Work piece(-) is connected to the negative terminal & Electrode(+) to the positive electrode .