SM 32x200 [2xM8] / N52 - magnetic separator

Advantages as well as disadvantages of rare earth magnets.

In addition to their magnetic efficiency, neodymium magnets provide the following advantages:

• They virtually do not lose strength, because even after 10 years the performance loss is only ~1% (based on calculations),
• They show high resistance to demagnetization induced by external disturbances,
• In other words, due to the aesthetic finish of silver, the element gains visual value,
• They are known for high magnetic induction at the operating surface, which increases their power,
• Thanks to resistance to high temperature, they can operate (depending on the form) even at temperatures up to 230°C and higher...
• Thanks to modularity in shaping and the ability to modify to specific needs,
• Fundamental importance in innovative solutions – they are commonly used in data components, motor assemblies, precision medical tools, as well as technologically advanced constructions.
• Relatively small size with high pulling force – neodymium magnets offer high power in tiny dimensions, which makes them useful in miniature devices

Disadvantages of neodymium magnets:

• Susceptibility to cracking is one of their disadvantages. Upon strong impact they can fracture. We recommend keeping them in a special holder, which not only secures them against impacts but also increases their durability
• Neodymium magnets demagnetize when exposed to high temperatures. After reaching 80°C, many of them experience permanent drop of power (a factor is the shape as well as dimensions of the magnet). We offer magnets specially adapted to work at temperatures up to 230°C marked [AH], which are extremely resistant to heat
• When exposed to humidity, magnets start to rust. To use them in conditions outside, it is recommended to use protective magnets, such as magnets in rubber or plastics, which secure oxidation as well as corrosion.
• Limited possibility of making nuts in the magnet and complex shapes - recommended is cover - magnet mounting.
• Potential hazard resulting from small fragments of magnets can be dangerous, if swallowed, which becomes key in the context of child health protection. Furthermore, small elements of these magnets are able to complicate diagnosis medical when they are in the body.
• With large orders the cost of neodymium magnets is a challenge,

Best holding force of the magnet in ideal parameters – what it depends on?

Holding force of 0 kg is a measurement result conducted under the following configuration:

• on a base made of structural steel, optimally conducting the magnetic flux
• whose thickness reaches at least 10 mm
• with an ground contact surface
• under conditions of gap-free contact (metal-to-metal)
• for force acting at a right angle (in the magnet axis)
• at standard ambient temperature

Lifting capacity in real conditions – factors

Effective lifting capacity is influenced by working environment parameters, mainly (from most important):

• Space between surfaces – even a fraction of a millimeter of separation (caused e.g. by veneer or dirt) drastically reduces the pulling force, often by half at just 0.5 mm.
• Direction of force – highest force is reached only during perpendicular pulling. The resistance to sliding of the magnet along the plate is typically many times lower (approx. 1/5 of the lifting capacity).
• Base massiveness – insufficiently thick plate does not accept the full field, causing part of the flux to be wasted to the other side.
• Material type – ideal substrate is high-permeability steel. Cast iron may generate lower lifting capacity.
• Surface condition – smooth surfaces ensure maximum contact, which increases force. Rough surfaces reduce efficiency.
• Thermal factor – hot environment weakens pulling force. Too high temperature can permanently demagnetize the magnet.

* Lifting capacity was measured with the use of a polished steel plate of suitable thickness (min. 20 mm), under perpendicular pulling force, whereas under attempts to slide the magnet the holding force is lower. Moreover, even a minimal clearance {between} the magnet’s surface and the plate lowers the load capacity.