In this method, heat is generated by passing an electric current across a gap between two conductors. A metal electrode is energized by a voltage source and then brought close to another metal object, thereby producing an arc of electric current between the two objects. A lot of heat is generated by this electric arc, causing the two rail ends to fuse or weld. This type of welding can be done using any of the following methods.
(a) Insert plate technique
(b) Scheron process
(c) Enclosed space technique
Indian Railways has recently started welding rail joints using the metal arc process on a trial basis and the performance so far has been satisfactory.