Ordinary steel, pure iron, stainless steel, red copper, brass, bronze, copper-clad steel, zinc-clad steel and so on.
RT-type exothermic welding: It is applied to the connection among earthing body, earthing wire, downward-drawn and overhead earthing wire. It is also called “maintenance-free connection”.
Exothermic welding is the welding method completed by utilizing the super heat generated during chemical reaction (combustion). For such welding method, the chemical reaction speed is very fast (only several seconds), extremely high heat is generated and dissolving part can be effectively transmitted; moreover, no other external thermal energy is required; so that exothermic welding is the best method for the connection of metallic conductors.
a The connection point is composed of atoms so that it has no contact surface and no mechanical pressure; therefore, loose weld or corrosion is avoided.
b Relatively large heat dissipation area and equal current flow ability with the conductor (temperature rise is lower than the conductor itself)
c It has the same melting point with the conductor so that it is able to bear the high current impact during repetitive fault. (the same fusing current with the conductor)
d The tension stress is stronger than the annealed copper wire.
e It will not be loosened or corroded. With the same current flow ability with the conductor, it will not be influenced by over-current and surge.
a No external heat source (for example, electricity) is required and the equipment is portable and mostly suitable for any on-site welding operation.
b The welding speed is fast and the portable and cheap equipment can be easily operated and used conveniently, so as to save manpower.
c The operation method is so simple that no welder or external welding machine is required.
d Since the casting weld mold is adopted, the joints have the same shape and quality is easily controlled (simple inspection is required).
e The total heat produced is greatly less than other welding methods and maintenance is not needed.