CM PML-10 / N45 - magnetic gripper

Strengths and weaknesses of neodymium magnets.

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

• They do not lose magnetism, even over nearly ten years – the reduction in power is only ~1% (theoretically),
• They are noted for resistance to demagnetization induced by external magnetic fields,
• Thanks to the shiny finish, the coating of Ni-Cu-Ni, gold-plated, or silver-plated gives an visually attractive appearance,
• Neodymium magnets create maximum magnetic induction on a small surface, which allows for strong attraction,
• Through (adequate) combination of ingredients, they can achieve high thermal strength, allowing for action at temperatures reaching 230°C and above...
• Possibility of individual shaping and modifying to precise needs,
• Wide application in electronics industry – they are used in mass storage devices, electromotive mechanisms, medical equipment, and technologically advanced constructions.
• Compactness – despite small sizes they generate large force, making them ideal for precision applications

Drawbacks and weaknesses of neodymium magnets and proposals for their use:

• To avoid cracks upon strong impacts, we recommend using special steel holders. Such a solution protects the magnet and simultaneously increases its durability.
• We warn that neodymium magnets can lose their power at high temperatures. To prevent this, we advise our specialized [AH] magnets, which work effectively even at 230°C.
• They oxidize in a humid environment. For use outdoors we suggest using waterproof magnets e.g. in rubber, plastic
• Due to limitations in realizing threads and complex forms in magnets, we recommend using casing - magnetic mount.
• Possible danger resulting from small fragments of magnets pose a threat, when accidentally swallowed, which becomes key in the context of child health protection. Additionally, small elements of these devices can disrupt the diagnostic process medical in case of swallowing.
• With large orders the cost of neodymium magnets can be a barrier,

Highest magnetic holding force – what affects it?

Holding force of 1000 kg is a measurement result conducted under specific, ideal conditions:

• on a base made of structural steel, effectively closing the magnetic flux
• with a cross-section minimum 10 mm
• with an ideally smooth contact surface
• without any insulating layer between the magnet and steel
• during detachment in a direction vertical to the mounting surface
• in stable room temperature

What influences lifting capacity in practice

Effective lifting capacity impacted by working environment parameters, mainly (from most important):

• Air gap (between the magnet and the metal), as even a tiny clearance (e.g. 0.5 mm) can cause a reduction in lifting capacity by up to 50% (this also applies to paint, rust or dirt).
• Load vector – highest force is reached only during perpendicular pulling. The force required to slide of the magnet along the plate is standardly many times lower (approx. 1/5 of the lifting capacity).
• Wall thickness – thin material does not allow full use of the magnet. Part of the magnetic field passes through the material instead of converting into lifting capacity.
• Plate material – low-carbon steel attracts best. Alloy steels decrease magnetic properties and lifting capacity.
• Surface finish – full contact is possible only on polished steel. Any scratches and bumps reduce the real contact area, weakening the magnet.
• Temperature – heating the magnet causes a temporary drop of induction. Check the maximum operating temperature for a given model.

* Holding force was tested on a smooth steel plate of 20 mm thickness, when a perpendicular force was applied, however under shearing force the lifting capacity is smaller. In addition, even a small distance {between} the magnet and the plate lowers the lifting capacity.