UMGW 48x24x11.5 [M8] GW / N38 - magnetic holder internal thread

Pros and cons of NdFeB magnets.

Apart from their notable holding force, neodymium magnets have these key benefits:

• They do not lose magnetism, even over around ten years – the decrease in power is only ~1% (according to tests),
• They are noted for resistance to demagnetization induced by external disturbances,
• The use of an aesthetic layer of noble metals (nickel, gold, silver) causes the element to have aesthetics,
• The surface of neodymium magnets generates a strong magnetic field – this is one of their assets,
• Made from properly selected components, these magnets show impressive resistance to high heat, enabling them to function (depending on their form) at temperatures up to 230°C and above...
• Thanks to freedom in shaping and the ability to modify to unusual requirements,
• Versatile presence in modern industrial fields – they are used in HDD drives, motor assemblies, medical devices, and multitasking production systems.
• Relatively small size with high pulling force – neodymium magnets offer impressive pulling force in tiny dimensions, which allows their use in miniature devices

Disadvantages of neodymium magnets:

• To avoid cracks upon strong impacts, we recommend using special steel housings. Such a solution protects the magnet and simultaneously increases its durability.
• Neodymium magnets lose power when exposed to high temperatures. After reaching 80°C, many of them experience permanent drop of power (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 extremely resistant to heat
• When exposed to humidity, magnets usually rust. For applications outside, it is recommended to use protective magnets, such as those in rubber or plastics, which prevent oxidation as well as corrosion.
• Limited possibility of creating threads in the magnet and complicated forms - preferred is casing - magnetic holder.
• Possible danger related to microscopic parts of magnets pose a threat, in case of ingestion, which gains importance in the context of child health protection. Furthermore, small components of these devices are able to disrupt the diagnostic process medical after entering the body.
• High unit price – neodymium magnets have a higher price than other types of magnets (e.g. ferrite), which can limit application in large quantities

Maximum magnetic pulling force – what it depends on?

The force parameter is a result of laboratory testing performed under the following configuration:

• using a base made of mild steel, acting as a ideal flux conductor
• whose transverse dimension equals approx. 10 mm
• with a surface free of scratches
• without any insulating layer between the magnet and steel
• under vertical application of breakaway force (90-degree angle)
• at room temperature

Determinants of lifting force in real conditions

Effective lifting capacity is affected by working environment parameters, such as (from most important):

• Distance (betwixt the magnet and the plate), because even a tiny clearance (e.g. 0.5 mm) can cause a reduction in force by up to 50% (this also applies to varnish, corrosion or dirt).
• Force direction – catalog parameter refers to pulling vertically. When applying parallel force, the magnet holds significantly lower power (typically approx. 20-30% of maximum force).
• Element thickness – for full efficiency, the steel must be sufficiently thick. Thin sheet restricts the attraction force (the magnet "punches through" it).
• Material type – the best choice is high-permeability steel. Cast iron may generate lower lifting capacity.
• Surface finish – ideal contact is possible only on smooth steel. Any scratches and bumps reduce the real contact area, reducing force.
• Temperature influence – hot environment reduces magnetic field. Exceeding the limit temperature can permanently demagnetize the magnet.

* Lifting capacity was measured by applying a polished steel plate of optimal thickness (min. 20 mm), under perpendicular detachment force, however under attempts to slide the magnet the load capacity is reduced by as much as fivefold. Moreover, even a small distance {between} the magnet’s surface and the plate lowers the load capacity.