With the popularity of induction heating equipment, more and more workpiece shapes are used for intermediate frequency heating equipment, because the workpiece is generally put into the induction heater (that is, induction heating coil) for heating. Therefore, we should design the induction coil suitable for heating according to the workpiece with different cross sections. Induction heaters commonly used for induction heating can be made into spiral sensors, slit sensors, flat circular sensors, special-shaped sensors, sensors with magnetic conductors, etc. Because there is no perfect theoretical design method for the inductor used in intermediate frequency heating equipment at present, the traditional method usually adopts the “empirical method” or the existing calculation formula, and because of the large error of the traditional manufacturing method, It will lead to the heating of the workpiece can not achieve the desired heating effect, then the intermediate frequency heating equipment sensor will have to be remade, resulting in a waste of human and financial resources.
In view of the disadvantages of the present manufacturing methods of induction heaters, the guiding ideology of low cost, high efficiency, safety and reliability is adopted in the research method of combining theory and experiment. The theoretical calculation value is modified by the experimental measurement of inductance, so as to improve the heating efficiency of the inductor. The main contents are as follows: firstly, by establishing the mathematical model between the induction heater (spiral) of intermediate frequency heating equipment and the heated workpiece, the calculation formula of the impedance of the general inductor is derived. Combined with the experimental results, various factors affecting the inductance value of the sensor are analyzed. Secondly, the general relationship between “partial inductance value” and “whole inductance value” of single-layer spiral coil element is derived by using the auxiliary design method of “spiral coil element”. And the influence of different materials (magnetic and non-magnetic materials) on the relationship between “part” and “whole”. Finally, according to the principle of induction EMF, the formulas for calculating the series parallel inductance of n finite length multi-layer coil elements are obtained by increasing the number of induction coils. When the end of the spiral coil element of multiple sizes is connected with the same name, the direction of the magnetic field produced by the current inflow of the metal heat treatment equipment is the same, and the inductance is much larger than that of the single layer coil. Therefore, the existing coil elements can be used for multi-layer series parallel connection to combine the inductance values we need.
Overseas manager: Tom Wang
Phone: 0086-13303078975(whatsapp, wechat,line)
Specialist of bar heat treatment furnace in China; Glad to be your business partner in induction heating field.
Post time: 06-05-2019