UMC 25x6/4x8 / N38 - cylindrical magnetic holder
cylindrical magnetic holder
Catalog no 320408
GTIN/EAN: 5906301814641
Diameter
25 mm [±1 mm]
internal diameter Ø
6/4 mm [±1 mm]
Height
8 mm [±1 mm]
Weight
21 g
Load capacity
14.00 kg / 137.29 N
Coating
[NiCuNi] Nickel
11.70 ZŁ with VAT / pcs + price for transport
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Technical parameters - UMC 25x6/4x8 / N38 - cylindrical magnetic holder
Specification / characteristics - UMC 25x6/4x8 / N38 - cylindrical magnetic holder
| properties | values |
|---|---|
| Cat. no. | 320408 |
| GTIN/EAN | 5906301814641 |
| Production/Distribution | Dhit sp. z o.o. |
| Country of origin | Poland / China / Germany |
| Customs code | 85059029 |
| Diameter | 25 mm [±1 mm] |
| internal diameter Ø | 6/4 mm [±1 mm] |
| Height | 8 mm [±1 mm] |
| Weight | 21 g |
| Load capacity ~ ? | 14.00 kg / 137.29 N |
| Coating | [NiCuNi] Nickel |
| Manufacturing Tolerance | ±1 mm |
Magnetic properties of material N38
| properties | values | units |
|---|---|---|
| remenance Br [min. - max.] ? | 12.2-12.6 | kGs |
| remenance Br [min. - max.] ? | 1220-1260 | mT |
| coercivity bHc ? | 10.8-11.5 | kOe |
| coercivity bHc ? | 860-915 | kA/m |
| actual internal force iHc | ≥ 12 | kOe |
| actual internal force iHc | ≥ 955 | kA/m |
| energy density [min. - max.] ? | 36-38 | BH max MGOe |
| energy density [min. - max.] ? | 287-303 | BH max KJ/m |
| max. temperature ? | ≤ 80 | °C |
Physical properties of sintered neodymium magnets Nd2Fe14B at 20°C
| properties | values | units |
|---|---|---|
| Vickers hardness | ≥550 | Hv |
| Density | ≥7.4 | g/cm3 |
| Curie Temperature TC | 312 - 380 | °C |
| Curie Temperature TF | 593 - 716 | °F |
| Specific resistance | 150 | μΩ⋅cm |
| Bending strength | 250 | MPa |
| Compressive strength | 1000~1100 | MPa |
| Thermal expansion parallel (∥) to orientation (M) | (3-4) x 10-6 | °C-1 |
| Thermal expansion perpendicular (⊥) to orientation (M) | -(1-3) x 10-6 | °C-1 |
| Young's modulus | 1.7 x 104 | kg/mm² |
Chemical composition
| iron (Fe) | 64% – 68% |
| neodymium (Nd) | 29% – 32% |
| boron (B) | 1.1% – 1.2% |
| dysprosium (Dy) | 0.5% – 2.0% |
| coating (Ni-Cu-Ni) | < 0.05% |
Ecology and recycling (GPSR)
| recyclability (EoL) | 100% |
| recycled raw materials | ~10% (pre-cons) |
| carbon footprint | low / zredukowany |
| waste code (EWC) | 16 02 16 |
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Strengths as well as weaknesses of Nd2Fe14B magnets.
Strengths
- They do not lose strength, even over approximately ten years – the drop in lifting capacity is only ~1% (based on measurements),
- They maintain their magnetic properties even under close interference source,
- Thanks to the metallic finish, the coating of Ni-Cu-Ni, gold-plated, or silver gives an aesthetic appearance,
- Magnetic induction on the working layer of the magnet remains maximum,
- 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 precise forming as well as adapting to individual applications,
- Huge importance in electronics industry – they are utilized in magnetic memories, motor assemblies, diagnostic systems, and industrial machines.
- Compactness – despite small sizes they provide effective action, making them ideal for precision applications
Cons
- To avoid cracks upon strong impacts, we recommend using special steel holders. Such a solution secures the magnet and simultaneously increases its durability.
- Neodymium magnets demagnetize 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 extremely resistant to heat
- When exposed to humidity, magnets start to rust. For applications outside, it is recommended to use protective magnets, such as those in rubber or plastics, which prevent oxidation as well as corrosion.
- We recommend a housing - magnetic mechanism, due to difficulties in producing threads inside the magnet and complex forms.
- Health risk related to microscopic parts of magnets can be dangerous, in case of ingestion, which becomes key in the context of child health protection. Furthermore, small elements of these devices can be problematic in diagnostics medical after entering the body.
- With mass production the cost of neodymium magnets is a challenge,
Pull force analysis
Maximum magnetic pulling force – what affects it?
- on a plate made of mild steel, effectively closing the magnetic field
- whose thickness equals approx. 10 mm
- with a plane free of scratches
- with direct contact (without paint)
- during pulling in a direction vertical to the mounting surface
- at temperature approx. 20 degrees Celsius
Practical lifting capacity: influencing factors
- Clearance – the presence of any layer (paint, tape, air) interrupts the magnetic circuit, which lowers power steeply (even by 50% at 0.5 mm).
- Force direction – remember that the magnet has greatest strength perpendicularly. Under sliding down, the capacity drops significantly, often to levels of 20-30% of the nominal value.
- Substrate thickness – for full efficiency, the steel must be sufficiently thick. Thin sheet restricts the attraction force (the magnet "punches through" it).
- Metal type – different alloys reacts the same. High carbon content weaken the interaction with the magnet.
- Base smoothness – the more even the plate, the larger the contact zone and stronger the hold. Roughness acts like micro-gaps.
- Temperature – temperature increase results in weakening of induction. It is worth remembering the maximum operating temperature for a given model.
Holding force was checked on a smooth steel plate of 20 mm thickness, when the force acted perpendicularly, whereas under attempts to slide the magnet the holding force is lower. Additionally, even a slight gap between the magnet’s surface and the plate lowers the holding force.
H&S for magnets
Avoid contact if allergic
Some people have a sensitization to Ni, which is the typical protective layer for NdFeB magnets. Extended handling can result in dermatitis. We recommend use protective gloves.
Medical interference
For implant holders: Strong magnetic fields affect medical devices. Maintain at least 30 cm distance or request help to handle the magnets.
Crushing force
Watch your fingers. Two large magnets will snap together immediately with a force of several hundred kilograms, crushing anything in their path. Be careful!
Maximum temperature
Regular neodymium magnets (N-type) lose power when the temperature exceeds 80°C. The loss of strength is permanent.
Handling rules
Exercise caution. Rare earth magnets act from a long distance and snap with massive power, often faster than you can react.
Cards and drives
Intense magnetic fields can erase data on payment cards, HDDs, and storage devices. Keep a distance of at least 10 cm.
Phone sensors
Navigation devices and mobile phones are extremely susceptible to magnetic fields. Direct contact with a powerful NdFeB magnet can permanently damage the internal compass in your phone.
Combustion hazard
Powder generated during machining of magnets is combustible. Do not drill into magnets unless you are an expert.
Product not for children
Absolutely store magnets away from children. Ingestion danger is significant, and the consequences of magnets connecting inside the body are tragic.
Fragile material
NdFeB magnets are sintered ceramics, which means they are fragile like glass. Clashing of two magnets leads to them cracking into shards.
Tabela kosztu i czasu dostawy
Płatność przed wysyłką:
GLS kurier
Przesyłka będzie u Ciebie za 2-3 dni
14.99 ZŁ
InPost Paczkomaty 24/7
Przesyłka będzie u Ciebie za 1-2 dni
12.30 ZŁ
Płatność przy odbiorze (pobranie):
GLS kurier
Przesyłka będzie u Ciebie za 1-2 dni
23.00 ZŁ
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