The heat released in the cutting process is generated by a chemical reaction by the oxygen that flows through a metal rod and the metal of the rod itself. The fuel of the chemical reaction is the carbon contained in the high-carbon grade alloy of the metal rod, with the entire chemical process being maintained by the most common of the oxidants, pure oxygen.
The most common ways to start the chemical reaction of the carbon in the metal rod (the fuel) and oxygen (the oxidant) stored in a nearby tank, are through an electric arc generated by a 10V battery or by a standard welding machine. The battery is used mainly in construction sites or locations that are remote and lack a proper supply of electricity. Once the rod lit, the electric power (either battery or welding machine) is discontinued because the metal continues to burn as the oxygen flow is maintained.
The exothermic reaction that takes place between the metal and the oxygen burns, melts and vaporises metal, non-ferrous alloys, aluminium, stainless steel, copper, nickel, brass, as well as concrete. Given the high temperature associated to this chemical reaction, the exothermic lance may also be used underwater.
The main fields of application of the exothermic lance are:
- construction sites
- cutting the metal bar reinforcements (e.g. in non-destructive demolition works)
- cutting very thick pipes (e.g. heat exchangers)
- post-earthquake victim extrication
- cutting concrete debris without causing vibrations
- cutting without vibrations any metal that blocks access to victims
- cutting the ship’s entire metal structure, both above and under water
- fire fighters and first aid units
- cutting a car’s body after a crash
- metal recycling