Loose pieces of metal in a fiber system can be destructive. They can cause sparks which in turn can cause fires. They can also tear up the wire on a card. It is imperative that metal is prevented from going through a fiber system. One of the primary defenses in the battle against this is the hump magnet. Magnets will attract ferrous metal, that is any metal containing iron or steel. Magnets will not attract aluminum or bronze.
Hump magnets are located between the balefeeds and the next piece of machinery which is usually some type of reserve. Fiber is blown through the hump magnet. The hump magnet actually contains two powerful magnets. Because of the magnet’s shape, the fiber is first blown against one magnet and then the other. Pieces of ferrous metal will stick to the magnets if they are not imbedded too deeply in the fiber.
The magnets are on hinges allowing them to be opened and cleaned when the fiber system is shut off. They should be cleaned daily to prevent a buildup of trash that would make the magnets ineffective. The magnets are very powerful so be careful not to get your watch or cell phone near them. The magnets can destroy a watch or phone.