SM 32x375 [2xM8] / N52 - magnetic separator

Pros as well as cons of NdFeB magnets.

Besides their immense field intensity, neodymium magnets offer the following advantages:

• They retain magnetic properties for nearly ten years – the drop is just ~1% (in theory),
• Neodymium magnets are highly resistant to magnetic field loss caused by magnetic disturbances,
• In other words, due to the shiny finish of silver, the element looks attractive,
• Magnetic induction on the surface of the magnet turns out to be impressive,
• Neodymium magnets are characterized by very high magnetic induction on the magnet surface and can work (depending on the shape) even at a temperature of 230°C or more...
• Thanks to freedom in constructing and the ability to adapt to complex applications,
• Significant place in modern industrial fields – they are utilized in magnetic memories, motor assemblies, precision medical tools, and modern systems.
• Relatively small size with high pulling force – neodymium magnets offer high power in tiny dimensions, which allows their use in compact constructions

Disadvantages of neodymium magnets:

• At very strong impacts they can crack, therefore we recommend placing them in steel cases. A metal housing provides additional protection against damage and increases the magnet's 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
• They rust in a humid environment. For use outdoors we advise using waterproof magnets e.g. in rubber, plastic
• Due to limitations in producing threads and complex shapes in magnets, we recommend using cover - magnetic mechanism.
• Possible danger related to microscopic parts of magnets pose a threat, when accidentally swallowed, which becomes key in the context of child health protection. Furthermore, small elements of these devices are able to complicate diagnosis medical when they are in the body.
• Due to neodymium price, their price is relatively high,

Best holding force of the magnet in ideal parameters – what contributes to it?

The load parameter shown concerns the peak performance, recorded under laboratory conditions, meaning:

• with the contact of a sheet made of special test steel, ensuring maximum field concentration
• possessing a thickness of at least 10 mm to ensure full flux closure
• with a surface free of scratches
• without any clearance between the magnet and steel
• for force acting at a right angle (in the magnet axis)
• at ambient temperature approx. 20 degrees Celsius

Practical aspects of lifting capacity – factors

In real-world applications, the actual holding force results from several key aspects, listed from crucial:

• Space between magnet and steel – every millimeter of distance (caused e.g. by veneer or dirt) significantly weakens the magnet efficiency, often by half at just 0.5 mm.
• Force direction – declared lifting capacity refers to detachment vertically. When attempting to slide, the magnet exhibits much less (often approx. 20-30% of maximum force).
• Plate thickness – too thin plate causes magnetic saturation, causing part of the flux to be wasted to the other side.
• Material type – the best choice is pure iron steel. Hardened steels may generate lower lifting capacity.
• Surface condition – ground elements guarantee perfect abutment, which increases field saturation. Rough surfaces reduce efficiency.
• Temperature influence – hot environment weakens magnetic field. Exceeding the limit temperature can permanently damage the magnet.

* Lifting capacity testing was conducted on plates with a smooth surface of suitable thickness, under a perpendicular pulling force, however under attempts to slide the magnet the load capacity is reduced by as much as 5 times. Moreover, even a minimal clearance {between} the magnet’s surface and the plate decreases the load capacity.