Design of induction coil for Forever billet induction heating furnace
Low frequency heating
Low frequency billet induction heating furnace is generally suitable for metal diathermy, especially those with large and relatively simple cross section. Typical applications are used for forging or extrusion of round or square billets with rounded corners and hot rolling of flat billets. In these cases, the coil design is generally simple, usually consisting of a helical tube or a deformed helical tube (such as a square, rectangular, irregular quadrilateral) that matches the cross-section shape of the basic workpiece. Low-frequency coils often have many turns, so a barrel-shaped inductor is usually formed. An auto-transformer can be used to match the high coil impedance with the inductor. In any case, the inductance of the coil or transformer must be high in order to reduce the number of oscillating capacitors needed to tune the resonant circuit frequency to the operating frequency. In general, the lower the frequency, the larger the coil or the greater the number of turns. When coupled with low inductance coils, it can be quite rare at low frequencies. In practice, this coil is often bought as part of the whole system and the whole operation is handled by the system supplier.
Intermediate and high frequency coils
Simple spiral pipes and deformed coils are commonly used in medium frequency and high frequency heat treatment applications. It includes single turn and multi turn coil, and the number of turns, oscillator circuit capacitance,the transformer ratio used for load matching and circuit modulation of transformer ratio need to be calculated by the computer software. Usually, in the application of intermediate and high frequency heating, especially the coil should have a special shape to ensure the coupling effect, so that the heating is uniform.
Inner surface heating coil
A major problem is often encountered for quenching, tempering or thermal assembly of inner holes. According to the actual needs, the inner diameter of 1.1cm inner hole is a small bore which can be heated by the 450kHZ power supply. When using 10kHz, the actual small inner diameter is 2.5cm. The inner coil should be as thin as possible, and the inner hole should be placed as close as possible to the surface of the coil. Because the current in the coil is flowing in the inductor, the distance for the large electromagnetic coupling components should be close to 0.16 cm. More coil or finer pitch in the inner ring can also increase the magnetic flux density. Therefore, the distance between turns should not exceed one time than the diameter of the coil, and the whole height of the coil should not exceed twice than its diameter.
More details about induction coils of induction heating equipment, welcome to contact with us.
Overseas manager: Tom Wang
Phone: 0086-13303078975(whatsapp, wechat,line)
Specialist of induction heating equipment is glad to be your partner in the field of induction heating.
Post time: 08-24-2018