SM 32x200 [2xM8] / N42 - magnetic separator

Pros as well as cons of NdFeB magnets.

Besides their durability, neodymium magnets are valued for these benefits:

• They virtually do not lose power, because even after 10 years the performance loss is only ~1% (in laboratory conditions),
• They are extremely resistant to demagnetization induced by external field influence,
• In other words, due to the smooth surface of gold, the element gains visual value,
• Neodymium magnets achieve maximum magnetic induction on a small area, which ensures high operational effectiveness,
• Made from properly selected components, these magnets show impressive resistance to high heat, enabling them to function (depending on their form) at temperatures up to 230°C and above...
• Possibility of custom modeling as well as adjusting to atypical needs,
• Versatile presence in modern industrial fields – they are utilized in HDD drives, electric drive systems, medical equipment, and technologically advanced constructions.
• Compactness – despite small sizes they provide effective action, making them ideal for precision applications

Problematic aspects of neodymium magnets and proposals for their use:

• To avoid cracks under impact, we recommend using special steel holders. Such a solution secures the magnet and simultaneously increases its durability.
• When exposed to high temperature, neodymium magnets suffer a drop in strength. Often, when the temperature exceeds 80°C, their strength decreases (depending on the size and shape of the magnet). For those who need magnets for extreme conditions, we offer [AH] versions withstanding up to 230°C
• Due to the susceptibility of magnets to corrosion in a humid environment, we recommend using waterproof magnets made of rubber, plastic or other material stable to moisture, in case of application outdoors
• We recommend a housing - magnetic holder, due to difficulties in realizing nuts inside the magnet and complex shapes.
• Health risk resulting from small fragments of magnets are risky, in case of ingestion, which is particularly important in the context of child safety. Furthermore, small components of these devices can disrupt the diagnostic process medical when they are in the body.
• With large orders the cost of neodymium magnets is a challenge,

Maximum lifting capacity of the magnet – what contributes to it?

The declared magnet strength concerns the peak performance, measured under laboratory conditions, specifically:

• with the contact of a yoke made of low-carbon steel, guaranteeing maximum field concentration
• with a cross-section minimum 10 mm
• with an ground touching surface
• under conditions of gap-free contact (metal-to-metal)
• for force applied at a right angle (pull-off, not shear)
• in temp. approx. 20°C

Lifting capacity in real conditions – factors

Holding efficiency is influenced by working environment parameters, including (from priority):

• Clearance – the presence of any layer (paint, dirt, gap) interrupts the magnetic circuit, which reduces capacity rapidly (even by 50% at 0.5 mm).
• Force direction – catalog parameter refers to detachment vertically. When applying parallel force, the magnet holds much less (typically approx. 20-30% of nominal force).
• Metal thickness – the thinner the sheet, the weaker the hold. Magnetic flux passes through the material instead of generating force.
• Plate material – mild steel gives the best results. Higher carbon content lower magnetic permeability and holding force.
• Plate texture – ground elements guarantee perfect abutment, which improves force. Uneven metal reduce efficiency.
• Thermal environment – temperature increase causes a temporary drop of induction. Check the thermal limit for a given model.

* Holding force was measured on a smooth steel plate of 20 mm thickness, when the force acted perpendicularly, in contrast under parallel forces the load capacity is reduced by as much as 5 times. Moreover, even a slight gap {between} the magnet’s surface and the plate decreases the lifting capacity.