SM 18x125 [2xM5] / N42 - magnetic separator

Strengths as well as weaknesses of neodymium magnets.

Besides their tremendous strength, neodymium magnets offer the following advantages:

• They retain full power for almost 10 years – the loss is just ~1% (based on simulations),
• They retain their magnetic properties even under strong external field,
• By applying a decorative coating of nickel, the element presents an nice look,
• Magnets possess impressive magnetic induction on the active area,
• Due to their durability and thermal resistance, neodymium magnets are capable of operate (depending on the shape) even at high temperatures reaching 230°C or more...
• Possibility of custom shaping and adjusting to complex applications,
• Universal use in innovative solutions – they find application in data components, electric drive systems, precision medical tools, also multitasking production systems.
• Relatively small size with high pulling force – neodymium magnets offer high power in small dimensions, which makes them useful in compact constructions

Disadvantages of neodymium magnets:

• At very strong impacts they can crack, therefore we advise placing them in special holders. 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 strength (a factor is the shape and 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
• Due to the susceptibility of magnets to corrosion in a humid environment, we recommend using waterproof magnets made of rubber, plastic or other material immune to moisture, when using outdoors
• We suggest cover - magnetic holder, due to difficulties in realizing nuts inside the magnet and complex shapes.
• Potential hazard to health – tiny shards of magnets can be dangerous, when accidentally swallowed, which becomes key in the aspect of protecting the youngest. Additionally, small components of these products can complicate diagnosis medical in case of swallowing.
• High unit price – neodymium magnets cost more than other types of magnets (e.g. ferrite), which hinders application in large quantities

Maximum lifting capacity of the magnet – what it depends on?

The load parameter shown refers to the limit force, obtained under ideal test conditions, specifically:

• using a sheet made of low-carbon steel, serving as a ideal flux conductor
• possessing a thickness of minimum 10 mm to ensure full flux closure
• with a plane cleaned and smooth
• without the slightest insulating layer between the magnet and steel
• under perpendicular force vector (90-degree angle)
• at room temperature

What influences lifting capacity in practice

Holding efficiency is influenced by specific conditions, including (from most important):

• Distance – the presence of any layer (rust, 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 exhibits significantly lower power (often approx. 20-30% of nominal force).
• Metal thickness – the thinner the sheet, the weaker the hold. Part of the magnetic field passes through the material instead of generating force.
• Steel grade – ideal substrate is high-permeability steel. Stainless steels may generate lower lifting capacity.
• Smoothness – full 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 induction. Check the maximum operating temperature for a given model.

* Lifting capacity testing was conducted on plates with a smooth surface of suitable thickness, under perpendicular forces, whereas under shearing force the holding force is lower. In addition, even a small distance {between} the magnet and the plate lowers the load capacity.