UMGGW 34x8 [M4] GW / N38 - magnetic holder rubber internal thread

Pros and cons of neodymium magnets.

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

• They virtually do not lose strength, because even after ten years the decline in efficiency is only ~1% (according to literature),
• They show high resistance to demagnetization induced by external disturbances,
• By covering with a shiny coating of silver, the element presents an elegant look,
• Magnetic induction on the working part of the magnet is exceptional,
• Thanks to resistance to high temperature, they are capable of working (depending on the shape) even at temperatures up to 230°C and higher...
• Possibility of detailed machining and optimizing to specific applications,
• Fundamental importance in innovative solutions – they are commonly used in computer drives, brushless drives, medical devices, as well as other advanced devices.
• Relatively small size with high pulling force – neodymium magnets offer impressive pulling force in tiny dimensions, which enables their usage in miniature devices

Disadvantages of neodymium magnets:

• At very strong impacts they can break, therefore we advise placing them in steel cases. A metal housing provides additional protection against damage, as well as increases the magnet's durability.
• When exposed to high temperature, neodymium magnets suffer a drop in force. Often, when the temperature exceeds 80°C, their power decreases (depending on the size, as well as shape of the magnet). For those who need magnets for extreme conditions, we offer [AH] versions withstanding up to 230°C
• Due to the susceptibility of magnets to corrosion in a humid environment, we recommend using waterproof magnets made of rubber, plastic or other material stable to moisture, when using outdoors
• Limited ability of producing nuts in the magnet and complicated shapes - recommended is cover - magnetic holder.
• Health risk resulting from small fragments of magnets can be dangerous, when accidentally swallowed, which gains importance in the context of child health protection. Furthermore, tiny parts of these devices can disrupt the diagnostic process medical when they are in the body.
• Higher cost of purchase is one of the disadvantages compared to ceramic magnets, especially in budget applications

Maximum magnetic pulling force – what affects it?

The specified lifting capacity represents the peak performance, recorded under optimal environment, specifically:

• on a base made of structural steel, effectively closing the magnetic field
• possessing a thickness of at least 10 mm to ensure full flux closure
• with an ground contact surface
• under conditions of ideal adhesion (metal-to-metal)
• for force acting at a right angle (pull-off, not shear)
• at temperature approx. 20 degrees Celsius

Practical lifting capacity: influencing factors

Bear in mind that the working load may be lower depending on the following factors, in order of importance:

• Clearance – existence of foreign body (paint, dirt, air) interrupts the magnetic circuit, which reduces power steeply (even by 50% at 0.5 mm).
• Pull-off angle – note that the magnet has greatest strength perpendicularly. Under sliding down, the holding force drops drastically, often to levels of 20-30% of the maximum value.
• Wall thickness – thin material does not allow full use of the magnet. Part of the magnetic field penetrates through instead of generating force.
• Material composition – different alloys attracts identically. High carbon content weaken the interaction with the magnet.
• Base smoothness – the more even the surface, the larger the contact zone and stronger the hold. Roughness acts like micro-gaps.
• Thermal environment – temperature increase causes a temporary drop of induction. It is worth remembering the maximum operating temperature for a given model.

* Holding force was checked on the plate surface of 20 mm thickness, when a perpendicular force was applied, whereas under parallel forces the holding force is lower. Additionally, even a minimal clearance {between} the magnet and the plate reduces the holding force.