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

Advantages as well as disadvantages of neodymium magnets.

Besides their stability, neodymium magnets are valued for these benefits:

• They virtually do not lose strength, because even after ten years the performance loss is only ~1% (in laboratory conditions),
• Magnets perfectly protect themselves against demagnetization caused by ambient magnetic noise,
• Thanks to the elegant finish, the surface of nickel, gold, or silver gives an professional appearance,
• The surface of neodymium magnets generates a concentrated magnetic field – this is a distinguishing feature,
• Neodymium magnets are characterized by very high magnetic induction on the magnet surface and are able to act (depending on the shape) even at a temperature of 230°C or more...
• In view of the possibility of accurate shaping and customization to specialized requirements, NdFeB magnets can be produced in a wide range of geometric configurations, which increases their versatility,
• Wide application in advanced technology sectors – they are commonly used in computer drives, motor assemblies, advanced medical instruments, and complex engineering applications.
• Compactness – despite small sizes they generate large force, making them ideal for precision applications

Cons of neodymium magnets: application proposals

• Susceptibility to cracking is one of their disadvantages. Upon strong impact they can fracture. We recommend keeping them in a steel housing, which not only protects them against impacts but also raises their durability
• Neodymium magnets lose force when exposed to high temperatures. After reaching 80°C, many of them experience permanent weakening 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
• Magnets exposed to a humid environment can rust. Therefore during using outdoors, we suggest using water-impermeable magnets made of rubber, plastic or other material resistant to moisture
• Due to limitations in realizing nuts and complex shapes in magnets, we recommend using casing - magnetic holder.
• Potential hazard resulting from small fragments of magnets are risky, in case of ingestion, which becomes key in the context of child safety. It is also worth noting that small components of these devices are able to disrupt the diagnostic process medical in case of swallowing.
• Due to neodymium price, their price is higher than average,

Maximum magnetic pulling force – what affects it?

Breakaway force is the result of a measurement for the most favorable conditions, assuming:

• with the application of a sheet made of low-carbon steel, guaranteeing maximum field concentration
• with a thickness no less than 10 mm
• characterized by smoothness
• without the slightest air gap between the magnet and steel
• under vertical force vector (90-degree angle)
• in neutral thermal conditions

Lifting capacity in practice – influencing factors

Bear in mind that the magnet holding may be lower influenced by the following factors, in order of importance:

• Air gap (between the magnet and the plate), because even a very small clearance (e.g. 0.5 mm) can cause a decrease in force by up to 50% (this also applies to paint, corrosion or debris).
• Force direction – note that the magnet has greatest strength perpendicularly. Under shear forces, the capacity drops significantly, often to levels of 20-30% of the maximum value.
• Steel thickness – insufficiently thick sheet does not accept the full field, causing part of the flux to be lost into the air.
• Material type – the best choice is high-permeability steel. Cast iron may generate lower lifting capacity.
• Surface quality – the smoother and more polished the plate, the larger the contact zone and higher the lifting capacity. Roughness creates an air distance.
• Heat – neodymium magnets have a negative temperature coefficient. At higher temperatures they are weaker, and at low temperatures they can be stronger (up to a certain limit).

* Lifting capacity was determined by applying a steel plate with a smooth surface of suitable thickness (min. 20 mm), under vertically applied force, in contrast under parallel forces the holding force is lower. In addition, even a slight gap {between} the magnet’s surface and the plate lowers the load capacity.