SMZR 32x125 / N52 - magnetic separator with handle

Pros as well as cons of rare earth magnets.

Besides their immense magnetic power, neodymium magnets offer the following advantages:

• They have stable power, and over more than 10 years their attraction force decreases symbolically – ~1% (in testing),
• Magnets effectively resist against loss of magnetization caused by ambient magnetic noise,
• A magnet with a metallic gold surface has an effective appearance,
• They feature high magnetic induction at the operating surface, making them more effective,
• Neodymium magnets are characterized by extremely high magnetic induction on the magnet surface and can function (depending on the form) even at a temperature of 230°C or more...
• Thanks to freedom in designing and the capacity to modify to client solutions,
• Significant place in future technologies – they are used in computer drives, electric drive systems, medical equipment, and technologically advanced constructions.
• Compactness – despite small sizes they generate large force, making them ideal for precision applications

Disadvantages of NdFeB magnets:

• They are fragile upon heavy impacts. To avoid cracks, it is worth protecting magnets in special housings. Such protection not only protects the magnet but also improves its resistance to damage
• We warn that neodymium magnets can lose their power at high temperatures. To prevent this, we recommend our specialized [AH] magnets, which work effectively even at 230°C.
• Magnets exposed to a humid environment can corrode. Therefore during using outdoors, we recommend using waterproof magnets made of rubber, plastic or other material protecting against moisture
• Due to limitations in creating threads and complicated forms in magnets, we propose using cover - magnetic holder.
• Possible danger to health – tiny shards of magnets are risky, in case of ingestion, which gains importance in the context of child safety. Additionally, small components of these products can complicate diagnosis medical in case of swallowing.
• With large orders the cost of neodymium magnets is economically unviable,

Magnetic strength at its maximum – what it depends on?

Magnet power is the result of a measurement for ideal contact conditions, taking into account:

• with the application of a sheet made of special test steel, ensuring full magnetic saturation
• whose transverse dimension reaches at least 10 mm
• with an ground touching surface
• without the slightest insulating layer between the magnet and steel
• during pulling in a direction perpendicular to the mounting surface
• at standard ambient temperature

Practical lifting capacity: influencing factors

During everyday use, the actual lifting capacity depends on many variables, ranked from the most important:

• Air gap (between the magnet and the plate), because even a tiny distance (e.g. 0.5 mm) leads to a drastic drop in lifting capacity by up to 50% (this also applies to varnish, rust or dirt).
• Load vector – maximum parameter is reached only during pulling at a 90° angle. The resistance to sliding of the magnet along the plate is standardly many times lower (approx. 1/5 of the lifting capacity).
• Plate thickness – too thin sheet does not close the flux, causing part of the power to be escaped into the air.
• Steel type – mild steel attracts best. Higher carbon content reduce magnetic permeability and lifting capacity.
• Surface condition – smooth surfaces guarantee perfect abutment, which improves force. Rough surfaces reduce efficiency.
• Thermal factor – hot environment reduces magnetic field. Too high temperature can permanently damage the magnet.

* Lifting capacity was determined with the use of a smooth steel plate of suitable thickness (min. 20 mm), under perpendicular detachment force, in contrast under parallel forces the holding force is lower. In addition, even a minimal clearance {between} the magnet’s surface and the plate lowers the load capacity.