Un-Brazing and Re-Brazing Copper Angle Brackets to Copper Strips at 1400°F (760°C) in Less than a Minute Using UltraFlex Induction Heating
December 4th, 2017 - The efficiency of UltraFlex Power Technologies Induction Heating systems has recently been demonstrated by the company’s engineers in a series of controlled tests. The goal of the tests was to evaluate the unbrazing and rebrazing capabilities of UltraFlex High Power Induction System from the UltraHeat L Series.
Two sets of materials were used for the tests: a copper right angle bracket, 4.3mm (0.170”) thick and copper strips, 1.3mm (0.05”) thick were used for the first test and three 2.5mm (0.1″) thick copper plates, along with two 1.6mm (0.06″) thick copper plates were taken for the second test.
The goal in both tests was to represent the use of an UltraFlex 25 kW power supply and hence the output power was limited to 25 kW. A second goal was to compare the use of two types of custom-designed coils and assess their efficiency. Custom coils are designed to optimize the heating process for each specific application and hence are critical for the success and efficiency of the heating process.
A pancake split earmuff coil was used in the first case, with the assembly being positioned in between the two coils. Induction heating with a temperature of 1400° F (760° C) and frequency of 48 kHz was then applied until the existing brazed bond was reflowed, within less than 60 seconds.
In the second test, using the same heating temperature and frequency, a rectangular coil was used, with the braze sample being positioned below the coil. The coil was ensured to be properly centered above and around the bracket. With this setting, a non-conductive solid fixture had to be used to counteract the electromagnetic forces that act on the coil and keep it on place above the bracket. Again, a heat cycle of only 60 seconds ensured the reflow of the existing braze in the heated area.
The two tests proved that UltraFlex High Power Induction System, completing the unbrazing and rebrazing within less than 60 seconds, was truly efficient for this application, with the split earmuff coil providing a more efficient heat source. However, if such coil design is not appropriate for the specific application, the coil design used in test 2 would supply the needed heat for the speedy and successful rebrazing process.
About UltraFlex Power Technologies:
Ultraflex Power Technologies (ultraflexpower.com) manufactures and sells induction heating power supplies. Induction power supplies generate a precise, targeted electromagnetic field that induces heat in conductive materials without the need for a flame or any contact with the material.
An induction heating system consists of an induction power supply and a custom-designed inductor (also known as a coil). The induction power supplies are universal systems, with custom coils designed to optimize the heating process for the specific application. These systems can be used for heating conductive materials in variety of applications ranging from metal melting and heat-treating to medical and nanoparticle research.
