Brazing offers many benefits to every user, including: low heat input, good electric conductivity and permanently leak-tight connections. However, the method of choice is critical. For example, if ovens or gas flames are used, heat transfers into the material relatively slowly. Induction brazing, on the other hand, has many advantages over flame soldering or furnace soldering.
Induction brazing: Energy-efficient and fast
The induction brazing process by EMAG subsidiary eldec, based in Dornstetten, Germany offers major benefits in this regard. The process is very energy-efficient and fast because induction delivers the heat directly into the workpiece. However, the applied technology is critical. Inductors and generators must be very specifically adapted to each application. They are built at eldec using elaborate production processes.
Induction brazing example: shading ring
The full efficiency of the inductive process is illustrated by an application example from wind power generator construction. Here the so-called shading rings are connected to the 2.5-ton rotor of the machine. For this purpose, the inductor is placed below the shading ring, which is then heated to 680 to 720 degrees Celsius. The inserted phosphorus brazing alloy melts and brazes the shading ring together with all the copper bars. The brazing process takes only three to four minutes. The temperature is controlled by pyrometer. The power supply is guaranteed by a medium-frequency model from the eldec CUSTOM LINE Series with 250 kW power.
Distortions ruled out
The greatest benefit of the application becomes evident by a look at the brazed joint. It shows little oxide formation and is of very high quality. In addition, only small amounts of heat dissipate into the bars during induction brazing. Therefore, distortions in the part are virtually ruled out.
Please see here for more information on induction brazing.
Brazing processes on a wind power generator: The inductor is placed below the shading ring and heats it to 680 to 720 degrees Celsius.
