SM 32x100 [2xM8] / N42 - magnetic separator

Advantages as well as disadvantages of rare earth magnets.

In addition to their pulling strength, neodymium magnets provide the following advantages:

• They have constant strength, and over around ten years their attraction force decreases symbolically – ~1% (in testing),
• Neodymium magnets are highly resistant to loss of magnetic properties caused by magnetic disturbances,
• A magnet with a metallic gold surface has better aesthetics,
• Magnets are characterized by extremely high magnetic induction on the active area,
• 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...
• Thanks to the ability of accurate shaping and adaptation to unique needs, neodymium magnets can be produced in a variety of shapes and sizes, which increases their versatility,
• Wide application in modern industrial fields – they are used in mass storage devices, electric motors, precision medical tools, also technologically advanced constructions.
• Relatively small size with high pulling force – neodymium magnets offer high power in compact dimensions, which makes them useful in small systems

Disadvantages of neodymium magnets:

• To avoid cracks upon strong impacts, we recommend using special steel housings. Such a solution secures the magnet and simultaneously increases its durability.
• We warn that neodymium magnets can lose their strength at high temperatures. To prevent this, we suggest our specialized [AH] magnets, which work effectively even at 230°C.
• They rust in a humid environment. For use outdoors we advise using waterproof magnets e.g. in rubber, plastic
• Due to limitations in creating threads and complex shapes in magnets, we propose using a housing - magnetic holder.
• Potential hazard to health – tiny shards of magnets are risky, in case of ingestion, which becomes key in the context of child safety. Additionally, tiny parts of these products are able to disrupt the diagnostic process medical in case of swallowing.
• High unit price – neodymium magnets cost more than other types of magnets (e.g. ferrite), which increases costs of application in large quantities

Maximum holding power of the magnet – what it depends on?

The declared magnet strength represents the limit force, obtained under ideal test conditions, meaning:

• using a sheet made of high-permeability steel, functioning as a circuit closing element
• whose transverse dimension equals approx. 10 mm
• characterized by smoothness
• without any insulating layer between the magnet and steel
• under vertical force vector (90-degree angle)
• at temperature approx. 20 degrees Celsius

Practical aspects of lifting capacity – factors

Bear in mind that the magnet holding will differ influenced by elements below, in order of importance:

• Clearance – the presence of any layer (paint, tape, gap) interrupts the magnetic circuit, which lowers capacity steeply (even by 50% at 0.5 mm).
• Loading method – declared lifting capacity refers to detachment vertically. When attempting to slide, the magnet holds much less (often approx. 20-30% of nominal force).
• Substrate thickness – to utilize 100% power, the steel must be adequately massive. Thin sheet restricts the lifting capacity (the magnet "punches through" it).
• Material type – the best choice is high-permeability steel. Cast iron may attract less.
• Surface condition – smooth surfaces guarantee perfect abutment, which improves force. Rough surfaces reduce efficiency.
• Temperature influence – high temperature weakens magnetic field. Too high temperature can permanently demagnetize the magnet.

* Lifting capacity was determined with the use of a smooth steel plate of optimal thickness (min. 20 mm), under perpendicular detachment force, whereas under parallel forces the lifting capacity is smaller. In addition, even a slight gap {between} the magnet and the plate reduces the lifting capacity.