BM 380x180x70 [4x M8] - magnetic beam

Strengths as well as weaknesses of rare earth magnets.

Besides their exceptional pulling force, neodymium magnets offer the following advantages:

• Their magnetic field remains stable, and after around ten years it drops only by ~1% (according to research),
• They do not lose their magnetic properties even under close interference source,
• Thanks to the smooth finish, the coating of nickel, gold-plated, or silver gives an visually attractive appearance,
• The surface of neodymium magnets generates a powerful magnetic field – this is one of their assets,
• Through (appropriate) combination of ingredients, they can achieve high thermal strength, allowing for operation at temperatures approaching 230°C and above...
• Possibility of precise forming and adjusting to individual applications,
• Fundamental importance in modern technologies – they are utilized in magnetic memories, electromotive mechanisms, medical devices, as well as technologically advanced constructions.
• Thanks to concentrated force, small magnets offer high operating force, with minimal size,

Disadvantages of neodymium magnets:

• They are fragile upon too strong impacts. To avoid cracks, it is worth protecting magnets using a steel holder. Such protection not only protects the magnet but also improves its resistance to damage
• We warn that neodymium magnets can lose their strength at high temperatures. To prevent this, we suggest our specialized [AH] magnets, which work effectively even at 230°C.
• When exposed to humidity, magnets usually rust. For applications outside, it is recommended to use protective magnets, such as magnets in rubber or plastics, which secure oxidation and corrosion.
• We recommend cover - magnetic holder, due to difficulties in creating threads inside the magnet and complex forms.
• Possible danger resulting from small fragments of magnets pose a threat, in case of ingestion, which becomes key in the context of child safety. Furthermore, small elements of these products can be problematic in diagnostics medical after entering the body.
• Due to complex production process, their price is relatively high,

Maximum lifting capacity of the magnet – what contributes to it?

The declared magnet strength represents the limit force, measured under optimal environment, specifically:

• on a plate made of mild steel, effectively closing the magnetic field
• with a thickness no less than 10 mm
• characterized by smoothness
• under conditions of gap-free contact (metal-to-metal)
• under axial force vector (90-degree angle)
• in temp. approx. 20°C

Determinants of lifting force in real conditions

Bear in mind that the working load may be lower depending on elements below, starting with the most relevant:

• Distance – existence of any layer (paint, tape, gap) acts as an insulator, which lowers capacity rapidly (even by 50% at 0.5 mm).
• Loading method – catalog parameter refers to detachment vertically. When applying parallel force, the magnet holds much less (often approx. 20-30% of maximum force).
• Plate thickness – too thin sheet does not close the flux, causing part of the flux to be lost into the air.
• Plate material – mild steel attracts best. Alloy admixtures lower magnetic properties and holding force.
• Plate texture – ground elements ensure maximum contact, which increases field saturation. Uneven metal reduce efficiency.
• Temperature influence – high temperature reduces magnetic field. Exceeding the limit temperature can permanently damage the magnet.

* Lifting capacity testing was performed on plates with a smooth surface of optimal thickness, under a perpendicular pulling force, however under attempts to slide the magnet the holding force is lower. In addition, even a slight gap {between} the magnet and the plate reduces the lifting capacity.