Single-Shot Induction Hardening: Improving Product Quality & Inductor Life

Single-shot induction hardening is a common method of hardening shaft-like components, particularly those featuring substantial geometric complexities (e.g. sharp external diameter transitions, wall thickness variations, lightening holes, slots, etc.) and requiring high production rates. Due to the inherent 3D electromagnetic nature of single-shot coils and the high power densities to which they are often subjected, designing coils that provide both quality hardening results and long coil life can be challenging. This paper illustrates the benefits of incorporating electromagnetic-thermal and thermo-mechanical computer simulation into the coil design process. A number of innovative single-shot coil design concepts and their practical quality and coil longevity advantages are also presented, including real-world hardening results and coil life data.