Superconductors are materials with very special properties. If cooled below a characteristic "critical temperature", their electrical resistance immediately drops to zero, and they can freeze the field of a permanent magnet at a defined distance – so that either the superconductor itself or the magnet hovers. These properties mean superconductors have vast potential for future industrial use. They can be used to support objects without needing any feedback control systems, or as part of a contactless, low-energy system for moving objects – even on the far side of walls. At the same time, this dust- and abrasion-free method is perfect for carefully transporting hovering objects in ultra-clean environments. As a leading global supplier of automation technology, FESTO has long devoted itself to researching and developing potential applications for superconductors and is revealing its latest results at HANNOVER MESSE.
One potential application is the contactless cleaning of an object encased in a SupraTube – a sealed vertical tube glass tube filled with liquid. A cryostat at the top helps superconductors keep a magnetic puck hovering at a distance of about five millimeters. When made to spin and released from the upper cryostat, the magnetic disc spirals downward through the tube until it is caught again and centered by the superconductor in the other cryostat at the bottom.