Reduction of Heat Losses for the In-line Induction Heating System by Optimization of Thermal Insulation

Improving the electrical energy efficiency of the manufacturing process is the imperative task to resolve the cost-saving pressure and environmental legislations. This paper focuses on a study on the thermal efficiency of the in-line induction heating systems that are using in the hot forking applications. Besides optimizing the process parameters that increase the electromagnetic and thermal efficiency, reducing the heat losses to the surrounding air is one of the practical ways to save the operating energy. The weakness of the current in-line induction heating systems were pointed out, and we proposed an insulating system to reduce the heat losses caused by convection and radiation. The analytical model of the heat transfer and the simulation model were built to calculate and verify the thermal efficiency of the insulating covers. The results show that using insulating covers at the open spaces between adjacent heaters of an in-line induction heating for automotive crankshaft forging can approximately reduce 9% of heat losses compared with the energy stored in the workpiece. The best values of the geometrical design parameters of the insulating cover were determined by solving the constrained optimization that considers some technological aspects of the proposed insulating system. This work is intended as a contribution to make the hot forging industry become greener and more efficient in terns of saving operating energy.