SM 18x250 [2xM5] / N42 - magnetic separator

Advantages as well as disadvantages of rare earth magnets.

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

• They virtually do not lose strength, because even after 10 years the performance loss is only ~1% (in laboratory conditions),
• Magnets perfectly resist against demagnetization caused by ambient magnetic noise,
• A magnet with a smooth silver surface has better aesthetics,
• Neodymium magnets generate maximum magnetic induction on a small area, which allows for strong attraction,
• Thanks to resistance to high temperature, they are capable of working (depending on the shape) even at temperatures up to 230°C and higher...
• Considering the option of precise shaping and customization to custom needs, NdFeB magnets can be produced in a variety of shapes and sizes, which expands the range of possible applications,
• Universal use in innovative solutions – they are utilized in data components, electromotive mechanisms, precision medical tools, and technologically advanced constructions.
• Compactness – despite small sizes they generate large force, making them ideal for precision applications

Disadvantages of NdFeB magnets:

• To avoid cracks upon strong impacts, we suggest using special steel holders. Such a solution secures the magnet and simultaneously improves its durability.
• We warn that neodymium magnets can reduce their strength at high temperatures. To prevent this, we suggest our specialized [AH] magnets, which work effectively even at 230°C.
• Due to the susceptibility of magnets to corrosion in a humid environment, we suggest using waterproof magnets made of rubber, plastic or other material immune to moisture, when using outdoors
• Due to limitations in producing nuts and complex shapes in magnets, we propose using cover - magnetic holder.
• Potential hazard related to microscopic parts of magnets are risky, if swallowed, which becomes key in the aspect of protecting the youngest. It is also worth noting that small elements of these magnets are able to be problematic in diagnostics medical when they are in the body.
• Due to complex production process, their price is relatively high,

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

The declared magnet strength concerns the maximum value, obtained under ideal test conditions, meaning:

• using a base made of low-carbon steel, serving as a magnetic yoke
• whose transverse dimension equals approx. 10 mm
• characterized by lack of roughness
• under conditions of ideal adhesion (surface-to-surface)
• under vertical force direction (90-degree angle)
• at ambient temperature room level

Practical aspects of lifting capacity – factors

It is worth knowing that the application force will differ depending on the following factors, in order of importance:

• Air gap (between the magnet and the plate), as even a tiny clearance (e.g. 0.5 mm) can cause a decrease in force by up to 50% (this also applies to varnish, corrosion or dirt).
• Force direction – catalog parameter refers to pulling vertically. When applying parallel force, the magnet holds significantly lower power (often approx. 20-30% of maximum force).
• Plate thickness – insufficiently thick steel does not close the flux, causing part of the power to be wasted into the air.
• Material composition – not every steel reacts the same. High carbon content worsen the interaction with the magnet.
• Surface structure – the more even the plate, the larger the contact zone and stronger the hold. Roughness acts like micro-gaps.
• Thermal environment – temperature increase causes a temporary drop of force. It is worth remembering the maximum operating temperature for a given model.

* Lifting capacity was determined by applying a smooth steel plate of suitable thickness (min. 20 mm), under perpendicular pulling force, whereas under shearing force the load capacity is reduced by as much as fivefold. Additionally, even a slight gap {between} the magnet and the plate decreases the lifting capacity.