The Difference Between Medium Frequency Induction Heating Machine and High Frequency Induction Heating Machine

The induction heating power supply originated in the 1950s and has now become a more popular heating power supply in industrial production. Its heating products are green and environmentally friendly, without waste smoke, exhaust gas, noise, or dust. So what is the difference between medium frequency induction heating machine and high frequency induction heating machine?

1. Medium frequency induction heating power supply

The frequency is relatively low, the projection depth of the induced current is large, and the heat transmission depth is relatively high. For large-size workpieces, the penetration is good. The frequency range of the medium frequency induction heating machine is generally between 1kHz and 10kHz, most of which are used for large tempering, quenching, tempering, heating, annealing of modular gears, large diameter thick wall pipes, large workpieces and large diameter shafts, and hot forging, smelting, and quenching of large layer depths.

2. Super audio frequency induction heating power supply

The working frequency band is mainly concentrated between 6KHz~60KHz. Compared with the equipment of 1~10KHz, this frequency band works without operating noise, and the current transmission depth is above 2mm. It is suitable for brazing and small size (typically such as round rods below 35mm)hot forging, hardening operation with a layer depth of about 2~4mm.

3. High frequency induction heating machine

The working frequency of high frequency induction heating machine is mainly concentrated between 60KHz~200KHz, and the current penetration depth is less than 2mm. It is suitable for brazing, hot forging of small size (typically round bars below 15mm), and quenching operations with a layer depth of about 1~2mm.

In fact, there is no standard answer to which frequency band is used in the selection of equipment. It mainly needs to be based on comprehensive considerations such as the customer's purchase cost, workpiece material, and process requirements. For example, low-power high-frequency equipment and higher-power ultra-audio equipment may have the same heating effect for certain workpieces.

Types of Induction Heating: How to Choose And Buy

Choosing the right induction heating power supply depends on several factors, including the material type, the thickness of the workpiece, the specific heating process, and the required heating speed. 

Medium frequency induction heating is versatile and works well for general heating applications where deeper heat penetration is needed, such as hardening and tempering of thicker metals. It provides a good balance between speed and depth, making it suitable for large-scale industrial operations. 

On the other hand, super audio frequency induction heating is best for applications requiring fine control, such as brazing, surface hardening, and smaller or intricate parts. Its high-frequency capabilities allow for faster and more precise heating of thin materials without over-heating the surrounding areas. 

High-frequency induction heating is ideal for tasks demanding rapid and shallow heating, such as soldering or processing delicate components. It’s perfect when minimal heat penetration is required, but fast, localized heating is essential. Ultimately, the choice of power supply will depend on your specific heating needs, material properties, and the desired efficiency of your process.