The induction preheating machine is generally used before hardening or welding conditions. For the quenching process preheating, the part that does the induction quenching process after the preheat treatment, can solve the heated parts deformation problem during the service process.

  Moreover, it can reduce the workpiece distortion during the hardening process, improve the hardening layer distribution, increase the hardening layer thickness, obtain the workpiece’s ideal metallographic structure and residual compressive stress, and eliminate the quenching cracks. Preheating for the welding process can slow down the cooling rate of the key weld cooling temperature range, prevent over-hardening, and reduce the ductility of the weld and heat-affected zone. It can reduce the shrinkage stress of weld and adjacent base metal, especially for high-stress welding joints.