Numerical Simulation Of Induction Heating Of Bars Before Forging And Analysis Of Electrothermal Properties

The induction heating generates heat by means of Joule effect resulting from an eddy current. It is widely used in billet forging production due to its high efficiency, precise control and low pollution. If the temperature difference between the center and surface of the blank is too large, the adjunctive stress and organization inside the blank will be asymmetry, and even lead to crack, which is harmful to the forming process and product quality. On the basis of heating performance requirements, in order to improve the product quality, heating efficiency and save resources, how to accurately control the input power, heating time and reasonable optimization the equipment structure, operating parameters are of great significance.In this paper, basing on the principle of induction heating, according to the characteristics of intermediate frequency induction forging furnaces, using the ANSYS FEM software, the mathematical models of electromagnetic field and temperature field are determined, as well as the solution of the boundary conditions. According to the simulation results, we can analysis the distribution of electromagnetic and temperature fields over the heating time, variation of eddy current power density during the heating temperature and heating time. Then according to the metal heating theory, it can be calculated that the function relation of the heating time and surface temperature when the metal heating enters a regular period. It can be used to verify that the model is correct.Using the established model and selecting different specifications of the bars, simulated and studied the heating performance. First of all, this paper studied the influence of the electric efficiency, the thermal efficiency and the electrothermal efficiency with the change of diameter and the input frequency. It obtained the optimum frequency that should be chosen in the same inductor heating the different specifications of bars. Second, this paper studied the influence of the electric efficiency, the thermal efficiency and the electrothermal efficiency with the change of diameter and the input power. It obtained the maximum power should be input under the condition of meeting the section temperature difference. Third, this paper studied how the electric efficiency, the thermal efficiency and the electrothermal efficiency change over time under the condition of meeting the section temperature difference and got the basis which could establish the heating schedule reasonably.This paper provides a mathematical model of bars induction heating equipment with furnace lining. Through the simulation method, analysis the electrothermal properties of the induction heating and provides reference for precisely controlling the section temperature distribution of forgings, improving product quality, reducing power consumption in practical production.