SKF Applies Its Magnetic Expertise to Design Portable Induction Heater

A portable induction heater from SKF demonstrates that the Swedish manufacturer applies its magnetics expertise in product development for more than magnetic bearings. A leading manufacturer of magnetic bearings as well as other types, SKF designed the heater to be make the hot-mounting of bearings a fast and safe operation. 

“All the operator has to do is to place the bearing in the center of the heater and connect a temperature probe to the top of inner ring or workpiece bore. With the push of a button, the TWIM 15 will heat the bearing to the target temperature for hot-mounting,” says Alberto Herrera, product development manager.  

Induction heaters introduce heat into a component using alternating magnetic fields. These fields create currents in the bearing or workpiece, which heats up owing to its natural resistance to electric currents, a process known as the Joule effect. The resulting increase in temperature causes the material to expand, allowing the bearing to be mounted without any friction or force. As soon as the bearing is correctly positioned and the temperature decreases, it contracts to its original form and creates the right interference fit on the shaft. 

This process reduces risks of damage to the bearing, shaft and operator compared with other methods for heating bearings such as oil baths or open flame. However, some induction heaters can cause overheating, which can damage the bearing. The TWIM 15 is fitted with a temperature probe, smart electronics and an advanced operating software, enabling the heater to optimize the heating process accordingly, ensuring that the bearing is heated safely and reliably. 

The temperature probe is a magnetic K-type 400 mm. The unit features a flat induction plate that does not require the use of a support yoke and it can heat a wide variety of bearings and components, including sensitive parts such as bearings with reduced clearance. For more info see