Induction brazing can solve many problems caused by flame torch or furnace oven, but the beauty of a good braze is just as great as the process itself.
Radyne had the privilege to work on an induction brazing project involving six steel rods brazed together with six rings on a steel platform at the same time. When presented with the project, we referred back to past brazing jobs when we heated multiple items at the same time with similar shapes. The IPEC (Induction Process Engineering Center) team decided to execute the project using Radyne’s Flexscan with a movable heat station. Like all projects, challenges present themselves when you least expected. One challenge the team faced was positioning the heat station in the right spot. Positing the heat station too high or too low would cause the braze rings to melt unevenly.
The first solution we approached was observing the client heating their parts and we measured the gap from the steel platform to the last turn of the coil. Learning the spacing in between the platform and coil gave even heating for each ring, but the rods were still uneven. The team ran multiple tests to learn why the rods were uneven, including watching the test through a thermal camera. The team concluded the rods were not made the same. The differences in the metal property were causing a magnetic distortion within the rods. Learning the parts themselves are unique, we decided to add Teflon under the steel platform. During the heat cycles, the Teflon provided an electric insulator to the steel platform, causing the steel rods to heat evenly.
The Teflon helped controlled the distortion within the rods and locating the right spot for the heat station almost solved every problem. The next challenge was controlling how fast the metal heats up. Controlling the rate of heat is just as important as the position of the heat. After many iterations, we decided to approach the challenge like driving a car. A driver will drive 70mph on the highway but will go 3mph going into a garage. The part will reach ideal temperatures and stay there for X minutes. After maintaining the temperatures, it will drop at a slow rate until the parts are cool off with water.
This induction brazing project was unique because of the magnetic distortion within each rod. When handling client’s induction problems the IPEC team and leadership are transparent with updates, issues, and success.