SGM Magnetics has been designing and supplying EPRs for industrial applications since 1974 and is not only the pioneer but also the world market leader in this technology.
Electro Permanent Magnets are lifting magnets made of two different types of permanent magnet blocks. These blocks either combine their respective magnetic fields (forces) into the load during the operating mode (lifting phase) or short-circuit them into each other during the resting mode.
The functioning of Electro Permanent Lifting Magnets
The transition from the resting mode to the operating one and vice versa is achieved by applying a short current impulse to one of the two permanent magnets, which changes its polarity (direction of its magnetic field).
Therefore, there is no use or need to supply the magnet with electrical current during the operating mode.
Electro Permanent Lifting Magnets [EPR] benefits
Safety: The lifting force of an EPR is exclusively based on the intrinsic force of its permanent magnets and is independent from any external source of energy. In the event of an accidental power failure or cable interruption, the load remains stable and there is no need for battery backup.
Duty cycle: The lifting force of EPRs remains constant and independent of the duty cycle (except for hot material applications), even after activation through a short current impulse.
Limits
Shallow magnetic field: EPRs are more suitable for applications where contact between magnet pole shoes and the load has limited air gaps because of their shallower magnetic field.
Temperature. Standard EPRs are suitable for hot material applications up to 250°C (480 °F), and special EPRs are suitable for material applications up to 450°C (840°F).
