UMGGW 29x8 [M4] GW / N38 - magnetic holder rubber internal thread

Pros and cons of rare earth magnets.

Apart from their consistent magnetism, neodymium magnets have these key benefits:

• They do not lose strength, even over around ten years – the decrease in strength is only ~1% (theoretically),
• They have excellent resistance to weakening of magnetic properties due to opposing magnetic fields,
• By using a decorative layer of gold, the element acquires an modern look,
• The surface of neodymium magnets generates a powerful magnetic field – this is a key feature,
• Due to their durability and thermal resistance, neodymium magnets can operate (depending on the form) even at high temperatures reaching 230°C or more...
• Possibility of individual forming and adapting to concrete conditions,
• Huge importance in high-tech industry – they find application in magnetic memories, electric motors, diagnostic systems, also multitasking production systems.
• Relatively small size with high pulling force – neodymium magnets offer impressive pulling force in compact dimensions, which allows their use in miniature devices

Drawbacks and weaknesses of neodymium magnets and ways of using them

• At strong impacts they can break, therefore we recommend placing them in steel cases. A metal housing provides additional protection against damage and increases the magnet's durability.
• NdFeB 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 extremely resistant to heat
• They rust in a humid environment. For use outdoors we suggest using waterproof magnets e.g. in rubber, plastic
• Due to limitations in creating threads and complicated shapes in magnets, we propose using cover - magnetic holder.
• Health risk resulting from small fragments of magnets can be dangerous, in case of ingestion, which gains importance in the context of child safety. Furthermore, tiny parts of these devices are able to disrupt the diagnostic process medical in case of swallowing.
• High unit price – neodymium magnets cost more than other types of magnets (e.g. ferrite), which can limit application in large quantities

Breakaway strength of the magnet in ideal conditions – what contributes to it?

Holding force of 6.4 kg is a measurement result performed under the following configuration:

• with the application of a yoke made of special test steel, guaranteeing maximum field concentration
• possessing a thickness of at least 10 mm to avoid saturation
• with an ideally smooth touching surface
• with direct contact (without coatings)
• during pulling in a direction vertical to the mounting surface
• in neutral thermal conditions

Determinants of practical lifting force of a magnet

Effective lifting capacity is affected by specific conditions, including (from priority):

• Space between magnet and steel – every millimeter of separation (caused e.g. by veneer or dirt) significantly weakens the pulling force, often by half at just 0.5 mm.
• Load vector – highest force is obtained only during perpendicular pulling. The shear force of the magnet along the plate is usually several times smaller (approx. 1/5 of the lifting capacity).
• Metal thickness – the thinner the sheet, the weaker the hold. Magnetic flux penetrates through instead of converting into lifting capacity.
• Material type – ideal substrate is high-permeability steel. Hardened steels may have worse magnetic properties.
• Surface structure – the smoother and more polished the plate, the larger the contact zone and stronger the hold. Unevenness creates an air distance.
• Temperature influence – hot environment weakens magnetic field. Too high temperature can permanently damage the magnet.

* Lifting capacity testing was performed on a smooth plate of optimal thickness, under a perpendicular pulling force, in contrast under parallel forces the lifting capacity is smaller. In addition, even a slight gap {between} the magnet and the plate reduces the holding force.