SM 32x150 [2xM8] / N52 - magnetic separator

Strengths and weaknesses of rare earth magnets.

Besides their high retention, neodymium magnets are valued for these benefits:

• Their strength is maintained, and after around ten years it decreases only by ~1% (according to research),
• Magnets very well resist against loss of magnetization caused by external fields,
• A magnet with a shiny nickel surface has an effective appearance,
• Magnets are distinguished by excellent magnetic induction on the active area,
• Made from properly selected components, these magnets show impressive resistance to high heat, enabling them to function (depending on their form) at temperatures up to 230°C and above...
• Possibility of accurate modeling and adapting to individual needs,
• Universal use in advanced technology sectors – they find application in hard drives, electromotive mechanisms, advanced medical instruments, and multitasking production systems.
• Relatively small size with high pulling force – neodymium magnets offer strong magnetic field in small dimensions, which enables their usage in compact constructions

Disadvantages of neodymium magnets:

• Susceptibility to cracking is one of their disadvantages. Upon strong impact they can break. We advise keeping them in a special holder, which not only secures them against impacts but also increases their durability
• NdFeB magnets lose power when exposed to high temperatures. After reaching 80°C, many of them experience permanent drop 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 very resistant to heat
• Due to the susceptibility of magnets to corrosion in a humid environment, we suggest using waterproof magnets made of rubber, plastic or other material stable to moisture, in case of application outdoors
• Limited ability of producing nuts in the magnet and complex forms - recommended is cover - magnetic holder.
• Potential hazard resulting from small fragments of magnets are risky, in case of ingestion, which is particularly important in the context of child safety. It is also worth noting that tiny parts of these devices are able to disrupt the diagnostic process medical when they are in the body.
• High unit price – neodymium magnets are more expensive than other types of magnets (e.g. ferrite), which can limit application in large quantities

Maximum lifting force for a neodymium magnet – what it depends on?

Magnet power is the result of a measurement for optimal configuration, taking into account:

• using a plate made of mild steel, functioning as a ideal flux conductor
• with a thickness no less than 10 mm
• with an polished touching surface
• with total lack of distance (without paint)
• for force acting at a right angle (in the magnet axis)
• in stable room temperature

Practical aspects of lifting capacity – factors

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

• Air gap (betwixt the magnet and the plate), as even a very small clearance (e.g. 0.5 mm) leads to a decrease in lifting capacity by up to 50% (this also applies to paint, corrosion or debris).
• Force direction – catalog parameter refers to detachment vertically. When attempting to slide, the magnet holds significantly lower power (typically approx. 20-30% of nominal force).
• Element thickness – for full efficiency, the steel must be adequately massive. Paper-thin metal limits the lifting capacity (the magnet "punches through" it).
• Steel type – low-carbon steel attracts best. Alloy admixtures lower magnetic properties and lifting capacity.
• Surface condition – ground elements ensure maximum contact, which improves field saturation. Uneven metal reduce efficiency.
• Temperature – temperature increase causes a temporary drop of force. Check the thermal limit for a given model.

* Lifting capacity was assessed by applying a steel plate with a smooth surface of optimal thickness (min. 20 mm), under perpendicular pulling force, in contrast under attempts to slide the magnet the holding force is lower. In addition, even a minimal clearance {between} the magnet and the plate lowers the lifting capacity.