SM 32x250 [2xM8] / N52 - magnetic separator

Advantages as well as disadvantages of neodymium magnets.

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

• They retain full power for around 10 years – the drop is just ~1% (according to analyses),
• Neodymium magnets are distinguished by exceptionally resistant to demagnetization caused by external interference,
• By using a decorative coating of nickel, the element has an aesthetic look,
• They feature high magnetic induction at the operating surface, which improves attraction properties,
• Through (adequate) combination of ingredients, they can achieve high thermal strength, enabling operation at temperatures approaching 230°C and above...
• Thanks to flexibility in shaping and the ability to modify to client solutions,
• Universal use in advanced technology sectors – they serve a role in data components, electric motors, advanced medical instruments, as well as multitasking production systems.
• Thanks to efficiency per cm³, small magnets offer high operating force, occupying minimum space,

Disadvantages of neodymium magnets:

• They are prone to damage upon heavy impacts. To avoid cracks, it is worth securing magnets in a protective case. Such protection not only protects the magnet but also increases its resistance to damage
• We warn that neodymium magnets can lose their power at high temperatures. To prevent this, we advise our specialized [AH] magnets, which work effectively even at 230°C.
• When exposed to humidity, magnets usually rust. For applications outside, it is recommended to use protective magnets, such as those in rubber or plastics, which secure oxidation as well as corrosion.
• Limited ability of producing threads in the magnet and complicated shapes - preferred is casing - mounting mechanism.
• Possible danger resulting from small fragments of magnets can be dangerous, if swallowed, which is particularly important in the context of child safety. Additionally, small components of these products can disrupt the diagnostic process medical after entering the body.
• Higher cost of purchase is one of the disadvantages compared to ceramic magnets, especially in budget applications

Maximum holding power of the magnet – what affects it?

The declared magnet strength represents the maximum value, measured under laboratory conditions, meaning:

• using a plate made of high-permeability steel, functioning as a ideal flux conductor
• whose thickness is min. 10 mm
• with an polished touching surface
• under conditions of ideal adhesion (surface-to-surface)
• under axial force vector (90-degree angle)
• in neutral thermal conditions

Lifting capacity in real conditions – factors

In practice, the real power is determined by a number of factors, listed from crucial:

• Distance (between the magnet and the plate), as even a microscopic distance (e.g. 0.5 mm) results in a drastic drop in force by up to 50% (this also applies to varnish, corrosion or debris).
• Angle of force application – highest force is obtained only during pulling at a 90° angle. The force required to slide of the magnet along the surface is usually several times lower (approx. 1/5 of the lifting capacity).
• Substrate thickness – for full efficiency, the steel must be sufficiently thick. Thin sheet limits the attraction force (the magnet "punches through" it).
• Steel grade – ideal substrate is pure iron steel. Cast iron may generate lower lifting capacity.
• Surface finish – ideal contact is possible only on smooth steel. Any scratches and bumps reduce the real contact area, reducing force.
• Thermal environment – temperature increase results in weakening of force. Check the thermal limit for a given model.

* Lifting capacity testing was performed on a smooth plate of suitable thickness, under a perpendicular pulling force, in contrast under shearing force the holding force is lower. In addition, even a small distance {between} the magnet’s surface and the plate reduces the load capacity.