SM 32x150 [2xM8] / N42 - magnetic separator

Pros and cons of NdFeB magnets.

Apart from their notable holding force, neodymium magnets have these key benefits:

• They virtually do not lose power, because even after ten years the performance loss is only ~1% (based on calculations),
• Magnets perfectly protect themselves against loss of magnetization caused by ambient magnetic noise,
• Thanks to the shimmering finish, the layer of nickel, gold-plated, or silver gives an aesthetic appearance,
• Neodymium magnets generate maximum magnetic induction on a small surface, which increases force concentration,
• Thanks to resistance to high temperature, they are able to function (depending on the form) even at temperatures up to 230°C and higher...
• In view of the option of accurate molding and customization to individualized needs, neodymium magnets can be produced in a variety of forms and dimensions, which amplifies use scope,
• Fundamental importance in modern technologies – they are used in computer drives, motor assemblies, diagnostic systems, as well as other advanced devices.
• Relatively small size with high pulling force – neodymium magnets offer high power in tiny dimensions, which allows their use in miniature devices

What to avoid - cons of neodymium magnets: tips and applications.

• They are fragile upon too strong impacts. To avoid cracks, it is worth securing magnets in special housings. Such protection not only shields the magnet but also improves its resistance to damage
• 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 very resistant to heat
• They rust in a humid environment. For use outdoors we advise using waterproof magnets e.g. in rubber, plastic
• We suggest casing - magnetic holder, due to difficulties in creating threads inside the magnet and complicated shapes.
• Health risk related to microscopic parts of magnets pose a threat, if swallowed, which is particularly important in the context of child safety. It is also worth noting that small elements of these magnets are able to be problematic in diagnostics medical in case of swallowing.
• Due to complex production process, their price is higher than average,

Maximum magnetic pulling force – what contributes to it?

The load parameter shown refers to the limit force, recorded under optimal environment, meaning:

• on a base made of structural steel, perfectly concentrating the magnetic flux
• possessing a thickness of at least 10 mm to ensure full flux closure
• with a surface cleaned and smooth
• without any clearance between the magnet and steel
• for force applied at a right angle (pull-off, not shear)
• at ambient temperature approx. 20 degrees Celsius

Determinants of practical lifting force of a magnet

During everyday use, the actual holding force results from a number of factors, presented from the most important:

• Distance – existence of foreign body (paint, dirt, gap) interrupts the magnetic circuit, which lowers capacity steeply (even by 50% at 0.5 mm).
• Force direction – note that the magnet has greatest strength perpendicularly. Under shear forces, the holding force drops significantly, often to levels of 20-30% of the maximum value.
• Substrate thickness – to utilize 100% power, the steel must be sufficiently thick. Thin sheet restricts the attraction force (the magnet "punches through" it).
• Steel grade – the best choice is pure iron steel. Cast iron may attract less.
• Surface finish – ideal contact is obtained only on smooth steel. Rough texture reduce the real contact area, reducing force.
• Temperature – heating the magnet results in weakening of induction. It is worth remembering the thermal limit for a given model.

* Lifting capacity was determined using a smooth steel plate of suitable thickness (min. 20 mm), under perpendicular detachment force, in contrast under parallel forces the lifting capacity is smaller. In addition, even a slight gap {between} the magnet and the plate reduces the load capacity.