SM 32x425 [2xM8] / N52 - magnetic separator

Pros and cons of NdFeB magnets.

Besides their high retention, neodymium magnets are valued for these benefits:

• Their magnetic field is durable, and after approximately ten years it decreases only by ~1% (theoretically),
• Neodymium magnets remain remarkably resistant to magnetic field loss caused by magnetic disturbances,
• Thanks to the shiny finish, the plating of Ni-Cu-Ni, gold, or silver gives an professional appearance,
• Magnets are distinguished by exceptionally strong magnetic induction on the outer side,
• Thanks to resistance to high temperature, they are capable of working (depending on the form) even at temperatures up to 230°C and higher...
• Thanks to modularity in shaping and the capacity to customize to client solutions,
• Fundamental importance in future technologies – they are used in hard drives, electromotive mechanisms, diagnostic systems, also other advanced devices.
• Compactness – despite small sizes they offer powerful magnetic field, making them ideal for precision applications

Disadvantages of neodymium magnets:

• At strong impacts they can break, therefore we recommend placing them in special holders. A metal housing provides additional protection against damage and increases the magnet's durability.
• When exposed to high temperature, neodymium magnets experience a drop in strength. Often, when the temperature exceeds 80°C, their power 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
• They oxidize in a humid environment - during use outdoors we suggest using waterproof magnets e.g. in rubber, plastic
• Due to limitations in creating nuts and complex forms in magnets, we recommend using a housing - magnetic holder.
• Health risk resulting from small fragments of magnets can be dangerous, when accidentally swallowed, which gains importance in the aspect of protecting the youngest. Furthermore, small elements of these magnets can be problematic in diagnostics medical after entering the body.
• Higher cost of purchase is a significant factor to consider compared to ceramic magnets, especially in budget applications

Magnetic strength at its maximum – what contributes to it?

Information about lifting capacity was determined for the most favorable conditions, assuming:

• with the application of a yoke made of special test steel, ensuring maximum field concentration
• whose thickness reaches at least 10 mm
• with a surface perfectly flat
• without any air gap between the magnet and steel
• under axial force direction (90-degree angle)
• at temperature approx. 20 degrees Celsius

Lifting capacity in real conditions – factors

During everyday use, the real power depends on several key aspects, presented from most significant:

• Space between surfaces – every millimeter of separation (caused e.g. by varnish or dirt) diminishes the magnet efficiency, often by half at just 0.5 mm.
• Loading method – catalog parameter refers to detachment vertically. When applying parallel force, the magnet exhibits much less (typically approx. 20-30% of nominal force).
• Metal thickness – thin material does not allow full use of the magnet. Part of the magnetic field penetrates through instead of converting into lifting capacity.
• Material type – ideal substrate is pure iron steel. Cast iron may generate lower lifting capacity.
• Base smoothness – the smoother and more polished the surface, the better the adhesion and higher the lifting capacity. Roughness creates an air distance.
• Temperature influence – hot environment weakens pulling force. Too high temperature can permanently damage the magnet.

* Holding force was checked on the plate surface of 20 mm thickness, when a perpendicular force was applied, in contrast under parallel forces the holding force is lower. Moreover, even a small distance {between} the magnet’s surface and the plate decreases the load capacity.