UMGGZ 88x8.5 [M8] GZ / N38 - rubber magnetic holder external thread

Strengths as well as weaknesses of NdFeB magnets.

Besides their tremendous magnetic power, neodymium magnets offer the following advantages:

• They have stable power, and over nearly ten years their performance decreases symbolically – ~1% (according to theory),
• Neodymium magnets are remarkably resistant to magnetic field loss caused by external field sources,
• The use of an metallic finish of noble metals (nickel, gold, silver) causes the element to look better,
• The surface of neodymium magnets generates a intense magnetic field – this is one of their assets,
• Thanks to resistance to high temperature, they are able to function (depending on the form) even at temperatures up to 230°C and higher...
• Possibility of accurate forming as well as modifying to precise requirements,
• Huge importance in high-tech industry – they find application in magnetic memories, electromotive mechanisms, diagnostic systems, and multitasking production systems.
• Compactness – despite small sizes they generate large force, making them ideal for precision applications

Disadvantages of NdFeB magnets:

• They are fragile upon too strong impacts. To avoid cracks, it is worth securing magnets using a steel holder. Such protection not only protects the magnet but also increases its resistance to damage
• We warn that neodymium magnets can reduce their power 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 corrode. Therefore during using outdoors, we recommend using waterproof magnets made of rubber, plastic or other material protecting against moisture
• Limited ability of producing threads in the magnet and complicated forms - preferred is a housing - mounting mechanism.
• Possible danger resulting from small fragments of magnets pose a threat, when accidentally swallowed, which is particularly important in the aspect of protecting the youngest. Furthermore, small elements of these magnets can complicate diagnosis medical after entering the body.
• With large orders the cost of neodymium magnets is a challenge,

Maximum magnetic pulling force – what contributes to it?

Holding force of 42.9 kg is a theoretical maximum value performed under specific, ideal conditions:

• using a sheet made of low-carbon steel, acting as a magnetic yoke
• with a thickness of at least 10 mm
• characterized by lack of roughness
• with zero gap (without impurities)
• for force applied at a right angle (in the magnet axis)
• in neutral thermal conditions

Magnet lifting force in use – key factors

Bear in mind that the magnet holding will differ subject to the following factors, in order of importance:

• Gap between magnet and steel – every millimeter of distance (caused e.g. by veneer or unevenness) significantly weakens the magnet efficiency, often by half at just 0.5 mm.
• Force direction – declared lifting capacity refers to detachment vertically. When applying parallel force, the magnet holds much less (often approx. 20-30% of maximum force).
• Element thickness – for full efficiency, the steel must be adequately massive. Paper-thin metal limits the lifting capacity (the magnet "punches through" it).
• Steel type – low-carbon steel attracts best. Alloy steels reduce magnetic properties and lifting capacity.
• Surface quality – the smoother and more polished the plate, the larger the contact zone and stronger the hold. Unevenness acts like micro-gaps.
• Thermal factor – high temperature reduces pulling force. Too high temperature can permanently demagnetize the magnet.

* Lifting capacity was measured with the use of a polished steel plate of optimal thickness (min. 20 mm), under perpendicular pulling force, in contrast under parallel forces the lifting capacity is smaller. Moreover, even a small distance {between} the magnet’s surface and the plate reduces the load capacity.