Role of Coil
The work coil, also known as the inductor, is the component in the induction heating system that defines how effective and how efficiently the work piece is heated.
The work coil is used to transfer the energy from the induction heating power supply and workhead to the work piece by generating an alternating electromagnetic field. The electromagnetic field generates a current that flows in the work piece as a mirror image to the current flowing in the work coil. As the current flows through the resistivity of the work piece it generates the heat within the work piece from I²R losses.
Importance of coil shape
Work coils range in complexity from a simple helical (or solenoid) wound coil consisting of a number of turns of copper tube wound around a mandrel to a coil precision machined from solid copper and brazed together.
Coils are made of copper tubing and are usually water cooled.
Coil size, shape (helical, round, square, etc.) and number of turns vary depending on the requirements at the time, such as the characteristics and shape of the heated object (work piece), the range to be heated, etc., and are related as shown in the table below.
| heated object (work piece) | Coil |
|---|---|
| Characteristics | Diameter |
| Size and shape | Shape |
| Position in the coil | Number of turns |
Coil design is essential to the effectiveness and efficiency of an induction heating process.
In addition to the heating process, consideration of ease of insertion and removal of the work piece to be heated maximizes the efficiency of the induction heating equipment.
Examples of coil shape
- Multi-turn Helical Coil
- Single-Turn Coil
- Multi-Position Helical Coil
- Channel Coil
- Curved Channel Coil
- Pancake Coil
- Split Helical Coil
- Internal Coil
EASYCOIL
The flexible EASYCOIL is a coil that is ideal for large, irregularly shaped work pieces that cannot be heated with a traditional copper coil. It is used with Ambrell EASYHEAT and EKOHEAT induction heating systems – up to the 250 kW model.
EASYCOIL Features and Benefits
- Works with EKOHEAT systems of up to 250 kW within a frequency range of 5-45 kHz
- Five 25’ (7.6 m) EASYCOILs can be coupled in series
- Most small and large parts can be coupled with equal effectiveness; it can be used for numerous applications
EASYCOIL is easy to wind and can be used on large and smaller parts. While the coil is 25’ (7.6 m) in length, it can be wound around a smaller part and couple just as effectively.
For heating large parts, up to five EASYCOILs can be used in series. Steel can be heated up to 816 ºC (1500 ºF ), and the power supply delivers full power.
The EASYCOIL has a glass fiber sleeve. While this coil is most popular for lower temperature applications, it can be used for through-Curie heating. When the surface temperature of the part is above 427 ºC (800 ºF), ceramic insulation, which we can supply, should be used.
Please ask us for coil shape
Alonics has designed and manufactured coils for induction heating adapted to a wide variety of applications, and has accumulated heating know-how. Our simulation software enables you to design coils more precisely.
The shape of the coil is important for an efficient heating process. Please feel free to contact us.