SM 32x400 [2xM8] / N42 - magnetic separator

Advantages and disadvantages of neodymium magnets.

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

• They do not lose strength, even after nearly ten years – the decrease in power is only ~1% (theoretically),
• They are noted for resistance to demagnetization induced by external field influence,
• A magnet with a shiny gold surface looks better,
• Magnets exhibit very high magnetic induction on the active area,
• Due to their durability and thermal resistance, neodymium magnets are capable of operate (depending on the form) even at high temperatures reaching 230°C or more...
• Thanks to modularity in constructing and the capacity to customize to complex applications,
• Key role in modern industrial fields – they serve a role in mass storage devices, motor assemblies, advanced medical instruments, as well as multitasking production systems.
• Thanks to concentrated force, small magnets offer high operating force, in miniature format,

Disadvantages of NdFeB magnets:

• Susceptibility to cracking is one of their disadvantages. Upon intense impact they can break. We advise keeping them in a steel housing, which not only protects them against impacts but also raises their durability
• Neodymium magnets demagnetize when exposed to high temperatures. After reaching 80°C, many of them experience permanent weakening of strength (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 - during use outdoors we advise using waterproof magnets e.g. in rubber, plastic
• We recommend a housing - magnetic mount, due to difficulties in realizing nuts inside the magnet and complicated shapes.
• Possible danger to health – tiny shards of magnets pose a threat, when accidentally swallowed, which becomes key in the context of child health protection. It is also worth noting that small elements of these devices are able to disrupt the diagnostic process medical when they are in the body.
• High unit price – neodymium magnets have a higher price than other types of magnets (e.g. ferrite), which increases costs of application in large quantities

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

Magnet power was determined for optimal configuration, including:

• using a sheet made of high-permeability steel, acting as a ideal flux conductor
• possessing a massiveness of at least 10 mm to avoid saturation
• characterized by even structure
• without the slightest air gap between the magnet and steel
• during pulling in a direction perpendicular to the plane
• at ambient temperature approx. 20 degrees Celsius

Magnet lifting force in use – key factors

It is worth knowing that the working load will differ influenced by the following factors, starting with the most relevant:

• Gap (between the magnet and the metal), because even a very small clearance (e.g. 0.5 mm) leads to a decrease in force by up to 50% (this also applies to varnish, rust or dirt).
• Force direction – catalog parameter refers to pulling vertically. When attempting to slide, the magnet exhibits much less (often approx. 20-30% of maximum force).
• Metal thickness – thin material does not allow full use of the magnet. Magnetic flux penetrates through instead of generating force.
• Metal type – different alloys attracts identically. Alloy additives weaken the attraction effect.
• Surface finish – ideal contact is possible only on polished steel. Any scratches and bumps reduce the real contact area, reducing force.
• Temperature – heating the magnet causes a temporary drop of force. It is worth remembering the maximum operating temperature for a given model.

* Lifting capacity testing was conducted on plates with a smooth surface of suitable thickness, under a perpendicular pulling force, whereas under parallel forces the lifting capacity is smaller. Additionally, even a small distance {between} the magnet and the plate reduces the load capacity.