Induction Annealing a Weld Seam

A company that manufactures venting solutions was looking to update their induction equipment, and they reached out to THE LAB at Ambrell to assess their process and take advantage of  complimentary applications testing. The process involved heating a weld seam for an annealing application. The client had stainless steel and galvanized steel tubes for this application. 

More Induction Annealing Application Notes

THE LAB at Ambrell determined that an Ambrell EASYHEAT^TM 4.2 kW, 150-400 kHz induction heating system was the right solution based on their application requirements. They also built a custom-designed single position coil. A piece of ceramic was secured to the bottom of the coil to ensure consistent positioning of the coil, and temperature indicating paint was applied to the part. 

Heating both the galvanized and stainless steel tubes took 6 seconds. However, testing revealed that the annealing temperature was 1300 °F (704 °C) for galvanized but 1000 °F (538 °C) for stainless. The galvanized tubes had very little discoloration from the heating, whereas the stainless steel tubes showed a bit more discoloration. 

Induction from Ambrell proved to be the right heating method for this application for a number of reasons. First off, the heating took just seconds, which can result in additional throughput for the client. In this case the system was being integrated into a material handling system and the EASYHEAT's modest footprint was very beneficial. Induction is consistent so the client will get the same result each time. Finally, the expertise of THE LAB with their free induction heating application testing was a key factor.