Traditionally, (manually operated) permanent lift magnets generate an external magnetic force through the rotation of a central rotor. The orientation of the internal magnets will determine whether the magnetic flux is directed through the poles into the load or away from the poles at “OFF”. Most designs involve a balancing of multiple magnets to avoid unwanted residual magnetism at the pole surface, but until now, harder materials are more likely to remain partially magnetized following release.
The design of DocMagnet’s lift magnets http://www.docmagnet.com/
Designed for performance and longevity, these units are also very distinctive in style. Four standard sizes are available—250, 500, 1000 and 2000 Lb safe working loads—to best fit your light and heavy lifting needs. Each lift magnet features a smooth lever action that rotates just 90° from “off” to “on” to make the switching process easy.
Each and every lift magnet is tested to exceed a 3-times safety factor (above industry standard), and each must undergo a high reluctant air-gap test. All lift magnets have a unique lever locking system that permits single-hand operation allowing the operator to support the load properly.
DocMagnet designs magnetic workholding http://www.docmagnet.com/