Exothermic weld - A perfect molecular weld
Exothermic welding connections are used widely in Earthing, Equipotential Bonding and Railway Applications. This weld process utilize the high temperature of the reaction between copper oxide and aluminium. The reaction happens in a graphite mould crucible, into which the pieces to be welded have been inserted. The molten metal from the exothermic reaction flows over the piece causing them to melt and fuse into a solid homogeneous mass.
The reaction in weld point so quick that the pieces to be welded get lower temperature on the zone around . The WELD connection is a perfect molecular weld and not just a me- chanical contact.
Connections are not affected by high current surges. Tests have shown that the electrical conductors will melt before the connection when subjected to high short-circuit current. Con- nection conductivity is at least equal or greater than the con- ductors welded. There is not possibility of corrosion at the point of the weld, since conductors become an integral part of the connection.
Exothermic Welding is possible between different metals
- Negligible contact resistance. Conductivity is equal or greater than welded conductors. Double cross section than welded material
- Highly Corrosion Resistant
- Withstand short-circuit and overload currents without affecting the connection. Conductors melts before the connection itself (Short-circuit current tests at CESI Lab. Italy)
- Conductors become an integral part of the welded material.
Exothermic Welding Models
Every model of exothermic welding need a graphite mould designed according to the Type of connection, conductor size and the surface area in which the bonding need to be done. The mould varies according to
Write a review