UMP 75x25 [M10x3] GW F200 GOLD DUAL / N42 - search holder

Strengths and weaknesses of rare earth magnets.

Besides their tremendous field intensity, neodymium magnets offer the following advantages:

• They have unchanged lifting capacity, and over nearly ten years their performance decreases symbolically – ~1% (according to theory),
• Magnets effectively defend themselves against loss of magnetization caused by ambient magnetic noise,
• A magnet with a shiny silver surface looks better,
• Neodymium magnets deliver maximum magnetic induction on a contact point, which allows for strong attraction,
• Thanks to resistance to high temperature, they are capable of working (depending on the form) even at temperatures up to 230°C and higher...
• Possibility of detailed machining and optimizing to concrete requirements,
• Significant place in innovative solutions – they are commonly used in hard drives, drive modules, medical equipment, also technologically advanced constructions.
• Thanks to their power density, small magnets offer high operating force, occupying minimum space,

Disadvantages of neodymium magnets:

• To avoid cracks under impact, we suggest using special steel holders. Such a solution secures the magnet and simultaneously improves its durability.
• Neodymium magnets lose power when exposed to high temperatures. After reaching 80°C, many of them experience permanent drop of strength (a factor is the shape and 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
• Magnets exposed to a humid environment can corrode. 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 complex forms in magnets, we propose using cover - magnetic mechanism.
• Health risk resulting from small fragments of magnets can be dangerous, if swallowed, which becomes key in the context of child health protection. Furthermore, small components of these products can complicate diagnosis medical after entering the body.
• High unit price – neodymium magnets cost more than other types of magnets (e.g. ferrite), which increases costs of application in large quantities

Best holding force of the magnet in ideal parameters – what it depends on?

Holding force of 601 kg is a theoretical maximum value conducted under the following configuration:

• on a base made of mild steel, optimally conducting the magnetic field
• with a thickness minimum 10 mm
• with an ideally smooth touching surface
• with direct contact (without paint)
• under vertical force vector (90-degree angle)
• at standard ambient temperature

What influences lifting capacity in practice

Bear in mind that the working load will differ depending on elements below, starting with the most relevant:

• Distance – existence of any layer (rust, tape, air) interrupts the magnetic circuit, which lowers capacity rapidly (even by 50% at 0.5 mm).
• Load vector – highest force is available only during perpendicular pulling. The resistance to sliding of the magnet along the surface is typically several times smaller (approx. 1/5 of the lifting capacity).
• Wall thickness – thin material does not allow full use of the magnet. Part of the magnetic field penetrates through instead of generating force.
• Steel grade – ideal substrate is pure iron steel. Cast iron may attract less.
• Surface quality – the more even the plate, the larger the contact zone and stronger the hold. Roughness acts like micro-gaps.
• Heat – NdFeB sinters have a sensitivity to temperature. When it is hot they lose power, and in frost they can be stronger (up to a certain limit).

* Lifting capacity was measured with the use of a steel plate with a smooth surface of optimal thickness (min. 20 mm), under vertically applied force, in contrast under parallel forces the load capacity is reduced by as much as fivefold. Additionally, even a small distance {between} the magnet and the plate lowers the load capacity.