To demonstrate the time and energy efficiency of induction heating for a variety of manufacturing applications, UltraFlex Power Technologies has recently set up tests aimed at timing the induction-ba sed brazing process for several steel assemblies.
In the tests, copper rings were used as alloy. The heating was done using an UltraFlex proprietary 5-15 kW induction heater from the W series, featuring operation in a wide frequency range (10 kHz – 400 kHz) and variable ratio output isolation transformer for load matching of a wide range of loads and coils.
5 different steel assemblies had been used in the test, with tubing outside diameter ranging from 0.19” (4.82mm) to 0.5”(12.7mm), fitting outside diameter ranging between 0.3”(7.62mm) and 0.6”(15.24mm) and overall length assembled between 7.75”(196.8mm) and 3.5”(88.9mm).
Part of the assemblies had tail fitting on both sides, others had banjo fitting applied. For all assemblies the same temperature of 1600°F (871°C) had been targeted.
For the assembly with the smallest, 0.19” (4.82mm) outside diameter of the tubing, at 7.75”(196.8mm) length assembled, it took as little as 40 seconds to achieve complete, reliable brazing. The power applied was 2.32 kW on average (after curie).
To cut the brazing time even more, for those tubes having bigger outside diameter increased power of up to 9.46 kW had been applied, which fit the entire brazing process into mere 10-15 seconds. Increasing the power was easy and fast, thanks to the induction heater's ability to release up to 15 kW of power, with power control from 10 to 100% in 1% increments.
For commercial brazing, it is recommended to use an IR system and temperature controller, to keep the parts from overheating and maintain a temperature letting the alloy to flow evenly around the braze joint. This would considerably improve the braze quality and time cycles. To prevent oxidation, it is also recommended to carry out the brazing process in a nitrogen or argon atmosphere.
The tests proved that the induction-ba sed brazing process is not only energy- and time-efficient, but it may also be swiftly tuned for optimum performance and results, for any type of brazing, melting or casting application. And, since no flame is involved in the process, it is completely safe and does not require a specific environment.
About UltraFlex Power Technologies:
UltraFlex Power Technologies (ultraflexpower.com) offers the most advanced and innovative digitally controlled induction heaters in the industry. Its compact modular and flexible systems are suitable for a wide variety of induction heating, casting and melting applications.