UMGGW 22x6 [M4] GW / N38 - magnetic holder rubber internal thread

Strengths and weaknesses of rare earth magnets.

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

• They retain attractive force for around ten years – the loss is just ~1% (according to analyses),
• They possess excellent resistance to magnetism drop due to opposing magnetic fields,
• Thanks to the shiny finish, the layer of nickel, gold, or silver gives an elegant appearance,
• Magnets exhibit huge magnetic induction on the active area,
• Thanks to resistance to high temperature, they can operate (depending on the shape) even at temperatures up to 230°C and higher...
• Thanks to flexibility in designing and the ability to customize to complex applications,
• Versatile presence in modern industrial fields – they are used in hard drives, electromotive mechanisms, medical devices, and industrial machines.
• Compactness – despite small sizes they generate large force, making them ideal for precision applications

Disadvantages of neodymium magnets:

• To avoid cracks upon strong impacts, we suggest using special steel holders. Such a solution protects the magnet and simultaneously improves its durability.
• Neodymium magnets demagnetize when exposed to high temperatures. After reaching 80°C, many of them experience permanent drop of power (a factor is the shape as well as dimensions of the magnet). We offer magnets specially adapted to work at temperatures up to 230°C marked [AH], which are very 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, in case of application outdoors
• Due to limitations in realizing threads and complex shapes in magnets, we recommend using cover - magnetic mechanism.
• Health risk resulting from small fragments of magnets pose a threat, in case of ingestion, which becomes key in the context of child health protection. It is also worth noting that small elements of these magnets can complicate diagnosis medical in case of swallowing.
• With mass production the cost of neodymium magnets can be a barrier,

Maximum magnetic pulling force – what contributes to it?

The specified lifting capacity represents the peak performance, obtained under laboratory conditions, namely:

• using a base made of mild steel, functioning as a ideal flux conductor
• possessing a massiveness of at least 10 mm to avoid saturation
• with a plane perfectly flat
• without any clearance between the magnet and steel
• during pulling in a direction perpendicular to the plane
• at ambient temperature approx. 20 degrees Celsius

Determinants of lifting force in real conditions

During everyday use, the actual holding force results from a number of factors, presented from most significant:

• Space between magnet and steel – even a fraction of a millimeter of separation (caused e.g. by veneer or unevenness) significantly weakens the pulling force, often by half at just 0.5 mm.
• Angle of force application – highest force is obtained only during perpendicular pulling. The force required to slide of the magnet along the plate is standardly many times smaller (approx. 1/5 of the lifting capacity).
• Metal thickness – thin material does not allow full use of the magnet. Part of the magnetic field passes through the material instead of generating force.
• Material type – the best choice is pure iron steel. Hardened steels may attract less.
• Surface quality – the more even the plate, the larger the contact zone and stronger the hold. Roughness acts like micro-gaps.
• Thermal factor – high temperature weakens pulling force. Too high temperature can permanently damage the magnet.

* Holding force was tested on the plate surface of 20 mm thickness, when a perpendicular force was applied, however under attempts to slide the magnet the lifting capacity is smaller. Moreover, even a minimal clearance {between} the magnet’s surface and the plate decreases the lifting capacity.