A lifting magnet is an electromagnet designed to pick up or lift metal objects. These magnets vary widely in size and can be as small as a credit card or as large as a twin-sized bed. Usually, the larger lifting magnets are operated hung from a chain on a crane that is able to dangle the magnet into the location necessary to retrieve the desired object. This type of magnet can be used for a wide variety of purposes, including automobile junking, construction, and demolition and cleanup.
Many kinds of lifting magnets exist. The most common ones are designed to lift heavy metal objects weighing several tons. Others, sometimes called magnetic sweepers, help collect debris like nails, screws, and small metal shards from construction site rubble. Using a magnet to retrieve metal shards from a construction site can help prevent injury and damage to vehicle tires.
A lifting magnet can also be called a retrieving magnet. They are most beneficial in situations in which another method of moving the metal object would be difficult, dangerous, or expensive. These magnets can be dropped into obscure locations to collect metal objects and debris from otherwise difficult-to-reach places. These magnets are also used in underwater situations in which retrieval of metal is required. These underwater magnets can be used to retrieve metal from a damaged submerged vessel like a sunken ship or wrecked oil well.
Larger, heavy-duty lifting magnets are often called scrap magnets. They can be used to lift large objects like scrapped vehicles. Specially designed scrap magnets have the ability to lift large coils of wire without risking the coil unwinding or telescoping. Telescoping is when the middle parts of the wire fall out of the center of the coil. When a wire coil telescopes, the heavy wire puts nearby people and objects at risk, and the wire is often difficult to re-coil after it telescopes.
If it is not used properly be trained individuals, a powerful lifting magnet can be dangerous. For safety, a high-powered lifting magnet is always placed on the intended lifting object before it is powered on. Placing the magnet on the correct object before powering it on reduces the chances of damaging other nearby objects with an out-of-control lifting magnet.