SM 32x150 [2xM8] / N52 - magnetic separator

Strengths and weaknesses of NdFeB magnets.

Besides their exceptional pulling force, neodymium magnets offer the following advantages:

• Their magnetic field is maintained, and after approximately ten years it decreases only by ~1% (according to research),
• Neodymium magnets are distinguished by remarkably resistant to magnetic field loss caused by magnetic disturbances,
• In other words, due to the glossy surface of gold, the element gains a professional look,
• The surface of neodymium magnets generates a intense magnetic field – this is a key feature,
• Due to their durability and thermal resistance, neodymium magnets can operate (depending on the form) even at high temperatures reaching 230°C or more...
• Considering the option of flexible forming and customization to unique requirements, neodymium magnets can be manufactured in a broad palette of geometric configurations, which increases their versatility,
• Versatile presence in innovative solutions – they serve a role in data components, electric motors, diagnostic systems, as well as complex engineering applications.
• Thanks to concentrated force, small magnets offer high operating force, with minimal size,

Disadvantages of NdFeB magnets:

• Brittleness is one of their disadvantages. Upon intense impact they can fracture. We recommend keeping them in a steel housing, which not only secures them against impacts but also increases their 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 recommend using waterproof magnets e.g. in rubber, plastic
• Limited ability of creating threads in the magnet and complicated forms - recommended is cover - magnet mounting.
• Potential hazard resulting from small fragments of magnets are risky, in case of ingestion, which gains importance in the aspect of protecting the youngest. It is also worth noting that small components of these products are able to complicate diagnosis medical in case of swallowing.
• Higher cost of purchase is a significant factor to consider compared to ceramic magnets, especially in budget applications

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

The declared magnet strength represents the peak performance, obtained under laboratory conditions, specifically:

• using a base made of low-carbon steel, serving as a circuit closing element
• possessing a thickness of at least 10 mm to ensure full flux closure
• with a surface cleaned and smooth
• with total lack of distance (no paint)
• during pulling in a direction vertical to the plane
• at temperature room level

Magnet lifting force in use – key factors

Please note that the application force will differ depending on elements below, starting with the most relevant:

• Clearance – existence of any layer (rust, dirt, gap) acts as an insulator, which reduces capacity steeply (even by 50% at 0.5 mm).
• Pull-off angle – remember that the magnet has greatest strength perpendicularly. Under sliding down, the capacity drops significantly, often to levels of 20-30% of the nominal value.
• Wall thickness – the thinner the sheet, the weaker the hold. Part of the magnetic field passes through the material instead of generating force.
• Steel grade – the best choice is high-permeability steel. Cast iron may have worse magnetic properties.
• Surface finish – ideal contact is obtained only on smooth steel. Rough texture reduce the real contact area, reducing force.
• Thermal conditions – NdFeB sinters have a negative temperature coefficient. At higher temperatures they lose power, and in frost they can be stronger (up to a certain limit).

* Lifting capacity was assessed with the use of a steel plate with a smooth surface of suitable thickness (min. 20 mm), under perpendicular detachment force, however under attempts to slide the magnet the lifting capacity is smaller. Moreover, even a slight gap {between} the magnet and the plate lowers the holding force.