UMGW 36x18x8 [M8] GW / N38 - magnetic holder internal thread

Pros and cons of rare earth magnets.

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

• They have stable power, and over more than 10 years their performance decreases symbolically – ~1% (according to theory),
• Neodymium magnets prove to be highly resistant to magnetic field loss caused by external magnetic fields,
• A magnet with a smooth silver surface has better aesthetics,
• Magnets have very high magnetic induction on the outer side,
• Due to their durability and thermal resistance, neodymium magnets can operate (depending on the shape) even at high temperatures reaching 230°C or more...
• Possibility of accurate machining as well as adapting to concrete applications,
• Significant place in modern technologies – they are commonly used in HDD drives, electric drive systems, advanced medical instruments, also industrial machines.
• Compactness – despite small sizes they generate large force, making them ideal for precision applications

Disadvantages of neodymium magnets:

• At strong impacts they can crack, 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 weakening of strength (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 recommend using waterproof magnets made of rubber, plastic or other material protecting against moisture
• Due to limitations in realizing threads and complicated shapes in magnets, we recommend using a housing - magnetic mount.
• Potential hazard related to microscopic parts of magnets are risky, if swallowed, which is particularly important in the context of child safety. Additionally, small elements of these magnets are able to complicate diagnosis medical when they are in the body.
• Due to neodymium price, their price is relatively high,

Magnetic strength at its maximum – what contributes to it?

The load parameter shown represents the limit force, recorded under laboratory conditions, meaning:

• with the contact of a sheet made of special test steel, guaranteeing full magnetic saturation
• with a thickness minimum 10 mm
• with an polished touching surface
• with total lack of distance (no coatings)
• during detachment in a direction perpendicular to the plane
• at ambient temperature room level

Determinants of lifting force in real conditions

Please note that the magnet holding will differ subject to the following factors, starting with the most relevant:

• Clearance – the presence of any layer (rust, dirt, gap) acts as an insulator, which reduces power rapidly (even by 50% at 0.5 mm).
• Load vector – highest force is available only during perpendicular pulling. The resistance to sliding of the magnet along the plate is usually several times lower (approx. 1/5 of the lifting capacity).
• Metal thickness – the thinner the sheet, the weaker the hold. Part of the magnetic field penetrates through instead of converting into lifting capacity.
• Material type – ideal substrate is high-permeability steel. Hardened steels may generate lower lifting capacity.
• Smoothness – ideal contact is obtained only on polished steel. Rough texture create air cushions, reducing force.
• Thermal conditions – neodymium magnets have a negative temperature coefficient. At higher temperatures they are weaker, and at low temperatures gain strength (up to a certain limit).

* Lifting capacity was measured using a steel plate with a smooth surface of suitable thickness (min. 20 mm), under perpendicular pulling force, however under shearing force the lifting capacity is smaller. In addition, even a slight gap {between} the magnet’s surface and the plate reduces the lifting capacity.