10 factors to consider when choosing an induction heating system

For certain applications, induction heating has a significant advantage over other popular heating methods. Is yours one of them?

Induction heating offers many benefits to manufacturing processes because it is a fast, energy-efficient and flameless method of heating electrically conductive materials. A typical system consists of an induction power supply, a workhead with a copper coil and a chiller or cooling system. Current flows through the coil creating an alternating electromagnetic field. When a conductive part is placed inside the coil, eddy currents are produced inside the element. The flow of eddy currents combined with the resistive properties of the conductive part generates heat inside it.

It is very important to choose the right system for your application and its requirements. A system with too much power can mean you spend more than you need, while a system with too little power can prolong the heating process and slow down production.

Here are 10 factors to consider when choosing an induction heating system.

1. Workpiece material

Induction directly heats conductive materials such as metals. Non-conductive materials are sometimes heated with a conductive susceptor. Due to hysteresis, magnetic materials heat up more easily than non-magnetic materials. Consequently, non-magnetic materials often require more power. Metals with high resistivity, such as steel, heat up quickly, while metals with low resistivity, such as copper or aluminum, take longer to heat up.

2. Depth of thermal penetration

The induced current will be most intense at the surface of the part. In fact, over 80% of the heat generated in a part is generated through skin effect on the surface. Therefore, larger parts and parts that need through heating require more time to heat up than those that are thin or small.

3. Operating frequency

Systems with lower frequency and higher power are suitable for heating larger parts that need through heating. Systems with lower power and higher frequency are often the right choice for surface heating. As a general rule, the higher the frequency, the shallower the heating of the part.

4. Power applied

The power output of an induction heating power supply determines the relative speed at which the part is heated. The mass of the part, temperature rise, and heat loss due to convection and conduction must be considered. The induction equipment manufacturer can assist in making this assessment.

5. Increase in required temperature

Induction can generate significant temperature changes, but generally more power is required to accommodate these changes, which will affect power supply selection. The rate of change of these temperatures can also affect the choice of such a power supply. The faster the rate of change, the greater the power requirement.

6. Coil design

The coil, which is typically water-cooled and made of copper, must conform to the shape of the part and account for process variables. An optimum coil design will deliver the correct proportion of heat to the part in an efficient manner. A poorly designed coil will heat the part more slowly and less efficiently. Flexible coils are now available and work well for large and geometrically unique parts.

7. Coupling Efficiency

Coupling a part to a coil increases current flow, which also increases the amount of heat generated in the part. Coupling allows for faster and more efficient heating, which can increase production efficiency. Weak coupling has the opposite effect.

8. Facility and workstation

The induction heating workstation requires cooling with a chiller or refrigeration system. Lower power systems typically require a compact water-to-air heat exchanger, while a higher power system may require a larger water-to-water heat exchanger or chiller. Additionally, space is needed for the power supply for the induction heater and the operating workhead. Overall, an induction system will save a lot of space compared to a furnace, especially when you consider that the workhead can be located a considerable distance from the power supply. Of course, you also need to make sure that the facility can handle the amount of power the system requires.

9. Additional requirements

Will you need to measure and store heating data? Some induction solution providers can offer a full system that includes an optical pyrometer and temperature monitoring software so that such data can be recorded and stored. A complete solution can lead to a seamless installation and commissioning.

10. Industrial experience

Many manufacturers of induction equipment have experience in specific applications, and if they have worked with your application, this will provide peace of mind. In addition, some suppliers offer lab testing and customized system recommendations based on your heating requirements. These types of services take the guesswork out of system selection and help you consider the factors mentioned above.

In summary, induction heating has many advantages over other common heating methods. Purchasing the right system for your application and ensuring that it meets any needs that may arise in the future will help your business take full advantage of its benefits.

DACPOL SERVICE provides comprehensive services for, among others, applications based on induction heating. We are able to select for you a solution that meets your application and requirements.

For more information please visit our website: https://www.dacpol.eu/en/induction-heating-80358.