UMGZ 42x20x9 [M8] GZ / N38 - magnetic holder external thread

Pros as well as cons of NdFeB magnets.

Apart from their strong power, neodymium magnets have these key benefits:

• They do not lose magnetism, even after around 10 years – the decrease in power is only ~1% (theoretically),
• They have excellent resistance to magnetic field loss due to external fields,
• A magnet with a metallic gold surface has better aesthetics,
• Magnets possess extremely high magnetic induction on the active area,
• Neodymium magnets are characterized by very high magnetic induction on the magnet surface and can work (depending on the form) even at a temperature of 230°C or more...
• Possibility of precise modeling as well as adapting to concrete needs,
• Significant place in modern industrial fields – they are used in magnetic memories, electric drive systems, medical equipment, also technologically advanced constructions.
• Compactness – despite small sizes they offer powerful magnetic field, making them ideal for precision applications

What to avoid - cons of neodymium magnets and proposals for their use:

• To avoid cracks under impact, we recommend using special steel holders. Such a solution secures the magnet and simultaneously increases its durability.
• Neodymium magnets lose strength when exposed to high temperatures. After reaching 80°C, many of them experience permanent weakening 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 advise using water-impermeable magnets made of rubber, plastic or other material protecting against moisture
• Limited ability of making threads in the magnet and complex shapes - preferred is casing - magnetic holder.
• Potential hazard resulting from small fragments of magnets can be dangerous, when accidentally swallowed, which gains importance in the aspect of protecting the youngest. Additionally, tiny parts of these products are able to be problematic in diagnostics medical in case of swallowing.
• Due to expensive raw materials, their price is higher than average,

Maximum lifting capacity of the magnet – what contributes to it?

The declared magnet strength refers to the maximum value, obtained under laboratory conditions, specifically:

• on a block made of structural steel, perfectly concentrating the magnetic flux
• whose transverse dimension reaches at least 10 mm
• with an ground contact surface
• with total lack of distance (no impurities)
• for force acting at a right angle (in the magnet axis)
• in stable room temperature

Practical lifting capacity: influencing factors

Real force is affected by specific conditions, including (from most important):

• Space between surfaces – every millimeter of distance (caused e.g. by varnish or unevenness) drastically reduces the pulling force, often by half at just 0.5 mm.
• Direction of force – highest force is reached only during pulling at a 90° angle. The resistance to sliding of the magnet along the plate is usually many times smaller (approx. 1/5 of the lifting capacity).
• Plate thickness – too thin plate causes magnetic saturation, causing part of the flux to be escaped into the air.
• Metal type – different alloys attracts identically. Alloy additives worsen the attraction effect.
• Base smoothness – the smoother and more polished the plate, the larger the contact zone and higher the lifting capacity. Unevenness creates an air distance.
• Temperature – heating the magnet results in weakening of force. It is worth remembering the thermal limit for a given model.

* Holding force was tested on a smooth steel plate of 20 mm thickness, when a perpendicular force was applied, in contrast under parallel forces the load capacity is reduced by as much as 5 times. Additionally, even a slight gap {between} the magnet’s surface and the plate lowers the holding force.