ADVANTAGES:
1.The heat necessary for welding is obtained from a chemical reaction and thus no costly power supply is required. Therefore broken parts (rails etc.) can be welded on the site itself.
2.For welding large fractured crankshafts.
3.For welding broken frames of machines.
4.For building up worn wobblers.
5.For welding sections of castings where size prevents there being cast in one piece.
6.For replacing broken teeth on large gears.
7.Forgings and flame cut sections may be welded together to make huge parts.
8.For welding new necks to rolling mill rolls and pinions.
9.For welding cables for electrical conductors.
10.For end welding of reinforcing bars to be used in concrete (building) construction.
LIMITATIONS:
1.Thermit welding is applicable only to ferrous metal parts of heavy sections, i.e., mill housings and heavy rail sections.
2.The process is uneconomical if used to weld cheap metals or light parts.