SM 32x425 [2xM8] / N42 - magnetic separator

Pros as well as cons of NdFeB magnets.

Besides their high retention, neodymium magnets are valued for these benefits:

• They do not lose strength, even during around 10 years – the drop in lifting capacity is only ~1% (based on measurements),
• Magnets effectively protect themselves against demagnetization caused by foreign field sources,
• A magnet with a smooth silver surface looks better,
• Magnets are distinguished by very 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 shape) at temperatures up to 230°C and above...
• In view of the ability of accurate shaping and adaptation to unique requirements, magnetic components can be produced in a variety of forms and dimensions, which expands the range of possible applications,
• Huge importance in modern industrial fields – they are commonly used in magnetic memories, electric motors, medical equipment, also complex engineering applications.
• Thanks to concentrated force, small magnets offer high operating force, with minimal size,

Disadvantages of neodymium magnets:

• Susceptibility to cracking is one of their disadvantages. Upon intense impact they can fracture. We advise keeping them in a strong case, which not only secures them against impacts but also raises their 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.
• Magnets exposed to a humid environment can rust. Therefore when using outdoors, we suggest using waterproof magnets made of rubber, plastic or other material protecting against moisture
• Due to limitations in producing nuts and complicated forms in magnets, we recommend using a housing - magnetic mount.
• Potential hazard resulting from small fragments of magnets pose a threat, if swallowed, which becomes key in the context of child health protection. It is also worth noting that small components of these magnets are able to complicate diagnosis medical when they are in the body.
• Higher cost of purchase is one of the disadvantages compared to ceramic magnets, especially in budget applications

Highest magnetic holding force – what it depends on?

The force parameter is a measurement result performed under standard conditions:

• on a block made of structural steel, optimally conducting the magnetic field
• with a cross-section minimum 10 mm
• with an ideally smooth contact surface
• without the slightest insulating layer between the magnet and steel
• for force acting at a right angle (pull-off, not shear)
• at ambient temperature room level

Lifting capacity in real conditions – factors

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

• Distance (betwixt the magnet and the plate), because even a very small clearance (e.g. 0.5 mm) results in a reduction in force by up to 50% (this also applies to varnish, corrosion or debris).
• Force direction – catalog parameter refers to detachment 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 passes through the material instead of generating force.
• Steel type – low-carbon steel gives the best results. Alloy steels decrease magnetic permeability and lifting capacity.
• Base smoothness – the more even the plate, the larger the contact zone and stronger the hold. Unevenness acts like micro-gaps.
• Temperature influence – high temperature reduces magnetic field. Too high temperature can permanently damage the magnet.

* Lifting capacity was assessed with the use of a polished steel plate of suitable thickness (min. 20 mm), under perpendicular pulling force, whereas under shearing force the holding force is lower. Additionally, even a slight gap {between} the magnet’s surface and the plate reduces the load capacity.