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neodymium magnets

We offer blue color magnetic Nd2Fe14B - our proposal. Practically all magnesy neodymowe in our store are available for immediate delivery (check the list). See the magnet pricing for more details see the magnet price list

Magnet for treasure hunters F200 GOLD

Where to buy very strong neodymium magnet? Holders with magnets in solid and airtight steel enclosure are excellent for use in difficult weather, including snow and rain more information...

magnets with holders

Holders with magnets can be used to improve production, underwater exploration, or searching for meteorites made of metal read...

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SM 25x250 [2xM8] / N42 - magnetic roller

magnetic separator

catalog number 130293

5.0

diameter Ø

25 mm [±0,1 mm]

height

250 mm [±0,1 mm]

max. temperature

≤ 80 °C

688.80 PLN gross price (including VAT) / pcs +

560.00 PLN net price + 23% VAT / pcs

bulk discounts:

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Call us tel: +48 888 99 98 98 or contact us through contact form on our website. You can check the strength as well as the shape of magnet in our magnetic calculator magnetic mass calculator

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Specification: magnetic separator 25x250 [2xM8] / N42

Characteristics: magnetic separator 25x250 [2xM8] / N42
Properties
Values
catalog number
130293
production / distribution
Dhit sp. z o.o.
country of origin
Poland / China / Germany
customs code
85059029
diameter Ø
25 mm [±0,1 mm]
height
250 mm [±0,1 mm]
max. temperature ?
≤ 80 °C
weight
0.01 g
execution tolerance
± 0.1 mm
rodzaj materiału
AISI 304 - bezpieczna dla żywności
rodzaj magnesów
NdFeB N42
ilość gwintów
2x [M8] wewnętrzne
biegunowość
obwodowa - 9 nabiegunników
indukcja magnetyczna
~ 6 500 Gauss [±5%]
max. temp. pracy
poniżej ≤ 80°C
grubość rury osłonowej
1 mm

Magnetic properties of the material N42

material characteristics N42
Properties
Values
units
remenance Br [Min. - Max.] ?
12.9-13.2
kGs
remenance Br [Min. - Max.] ?
1290-1320
T
coercivity bHc ?
10.8-12.0
kOe
coercivity bHc ?
860-955
kA/m
actual internal force iHc
≥ 12
kOe
actual internal force iHc
≥ 955
kA/m
energy density [Min. - Max.]
40-42
BH max MGOe
energy density [Min. - Max.]
318-334
BH max KJ/m
max. temperature
≤ 80
°C

Physical properties of sintered neodymium magnets Nd2Fe14B

Physical properties of sintered neodymium magnets Nd2Fe14B
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 106
°C-1
Thermal expansion perpendicular (⊥) to orientation (M)
-(1-3) x 10-6
°C-1
Young's modulus
1.7 x 104
kg/mm²
The main mechanism of the magnetic separator is the use of neodymium magnets, which are embedded in a construction made of stainless steel mostly AISI304. As a result, it is possible to effectively segregate ferromagnetic particles from the mixture. An important element of its operation is the use of repulsion of N and S poles of neodymium magnets, which enables magnetic substances to be targeted. The thickness of the embedded magnet and its structure's pitch affect the range and strength of the separator's operation.
Generally speaking, magnetic separators serve to segregate ferromagnetic elements. If the cans are made of ferromagnetic materials, the separator will be able to separate them. However, if the cans are made of non-ferromagnetic materials, such as aluminum, the separator will not effectively segregate them.
Yes, magnetic rollers are employed in the food industry for the elimination of metallic contaminants, such as iron fragments or iron dust. Our rollers are made from acid-resistant steel, EN 1.4301, suitable for use in food.
Magnetic rollers, otherwise magnetic separators, are employed in food production, metal separation as well as recycling. They help in eliminating iron dust in the course of the process of separating metals from other wastes.
Our magnetic rollers are built with neodymium magnets anchored in a stainless steel tube casing of stainless steel with a wall thickness of 1mm.
Both ends of the magnetic bar will be with M8 threaded holes - 18 mm, which enables quick installation in machines or magnetic filter drawers. A "blind" version is also possible in manual separators.
In terms of features, magnetic bars differ in terms of flux density, magnetic force lines and the area of operation of the magnetic field. We produce them in two materials, N42 and N52.
Often it is believed that the greater the magnet's power, the better. Nevertheless, the value of the magnet's power is dependent on the height of the used magnet and the quality of the material [N42] or [N52], as well as on the area of use and specific needs. The standard operating temperature of a magnetic bar is 80°C.
When the magnet is more flat, the magnetic force lines are more compressed. On the other hand, in the case of a thicker magnet, the force lines are longer and reach further.
For constructing the casings of magnetic separators - rollers, frequently stainless steel is utilized, particularly types AISI 304, AISI 316, and AISI 316L.
In a salt water environment, AISI 316 steel is highly recommended due to its excellent corrosion resistance.
Magnetic bars stand out for their specific arrangement of poles and their capability to attract magnetic substances directly onto their surface, in contrast to other devices that often use more complicated filtration systems.
Technical designations and terms related to magnetic separators comprise amongst others polarity, magnetic induction, magnet pitch, as well as the steel type applied.
Magnetic induction for a magnet on a roller is determined using a teslameter or a gaussmeter with a flat Hall-effect probe, aiming to find the highest magnetic field value close to the magnetic pole. The outcome is verified in a value table - the lowest is N30. All designations less than N27 or N25 indicate recycling that falls below the standard - they are not suitable.
Neodymium magnetic bars offer a range of benefits such as excellent separation efficiency, strong magnetic field, and durability. Disadvantages may include higher cost compared to other types of magnets and the need for regular maintenance.
For proper maintenance of neodymium magnetic rollers, it is recommended {to clean them regularly from contaminants, avoid extreme temperatures above 80 degrees, and cleaning regularly, avoiding temperatures up to 80°C. The rollers have an IP67 waterproof rating, so if they are not sealed, the magnets inside may oxidize and weaken. Roller inspections are recommended to be conducted every two years. Caution should be exercised during use as there is a possibility of finger injury. If the protective tube is only 0.5 mm thick, it can be worn down, which, in turn, can result in issues with the magnetic rod becoming unsealed and product contamination. The effective operating range of the roller equals its diameter, fi25mm is approximately 25mm active range, while fi32 is about 40mm.

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Advantages as well as disadvantages of neodymium magnets NdFeB.

Apart from immense power, neodymium magnets have the following advantages:

  • They do not lose their power (of the magnet). After approximately 10 years, their power decreases by only ~1% (theoretically),
  • They protect against demagnetization caused by external magnetic field very well,
  • By applying a shiny coating of nickel, gold, or silver, the element gains an aesthetic appearance,
  • They have very high magnetic induction on the surface of the magnet,
  • Thanks to their high temperature resistance, they can operate (depending on the form) even at temperatures up to 230°C and above...
  • Thanks to the flexibility in shaping and the ability to adapt to specific requirements – neodymium magnets can be produced in a wide range of shapes and sizes, which expands the range of their possible uses.
  • Significant importance in advanced technologically fields – are utilized in HDD drives, electric drive mechanisms, medical apparatus and various technologically advanced devices.

Disadvantages of neodymium magnets:

  • They are prone to breaking as they are extremely fragile when subjected to a strong impact. If the magnets are exposed to impacts, we recommend using magnets in a steel housing. The steel housing in the form of a holder protects the magnet from impacts and also increases its overall strength,
  • High temperatures can reduce the power of neodymium magnets. Typically, after heating above 80°C, most of them experience a permanent reduction in strength (although it is dependent on the shape and size). To prevent this, we offer special magnets marked with the symbol [AH], which are highly resistant to high temperatures. They can operate even at temperatures up to 230°C, making them an ideal solution for applications requiring high-temperature operation,
  • They rust in a humid environment. For outdoor use, we recommend using waterproof magnets, such as those made of rubber or plastic,
  • The use of a cover or a magnetic holder is recommended due to the limited possibilities of manufacturing threads or complex shapes in the magnet
  • Potential hazard arising from small pieces of magnets can be dangerous, when accidentally ingested, which is particularly important in the aspect of protecting young children. Furthermore, small elements of these devices can be problematic in medical diagnosis when they are in the body.

Safety Precautions

Magnets made of neodymium are extremely delicate, they easily crack and can crumble.

Magnets made of neodymium are fragile and will shatter if allowed to collide with each other, even from a distance of a few centimeters. Despite being made of metal as well as coated with a shiny nickel plating, they are not as hard as steel. In the case of a collision between two magnets, there can be a scattering of small sharp metal fragments in different directions. Protecting your eyes is essential.

Under no circumstances should neodymium magnets be brought close to GPS and smartphones.

Intense magnetic fields generated by neodymium magnets interfere with compasses and magnetometers used in navigation, as well as internal compasses of smartphones and GPS devices.

Neodymium magnets are not recommended for people with pacemakers.

Neodymium magnets produce strong magnetic fields that can interfere with the operation of a heart pacemaker. Even if the magnetic field does not affect the device, it can damage its components or deactivate the entire device.

Dust and powder from neodymium magnets are flammable.

Do not attempt to drill into neodymium magnets. Mechanical processing is also not recommended. Once crushed into fine powder or dust, this material becomes highly flammable.

Magnets will attract to each other, so remember not to allow them to pinch together without control or place your fingers in their path.

Neodymium magnets jump and also clash mutually within a radius of several to around 10 cm from each other.

 Maintain neodymium magnets away from youngest children.

Not all neodymium magnets are toys, so do not let children play with them. In such a situation, surgery is necessary to remove them. In the worst case scenario, it can result in death.

Do not place neodymium magnets near a computer HDD, TV, and wallet.

Neodymium magnets generate intense magnetic fields that can destroy magnetic media such as floppy disks, video tapes, HDDs, credit cards, magnetic ID cards, cassette tapes, or other devices. They can also destroy videos, televisions, CRT computer monitors. Remember not to place neodymium magnets close to these electronic devices.

Neodymium magnets are among the strongest magnets on Earth. The astonishing force they generate between each other can shock you.

Read the information on our website on how to properly utilize neodymium magnets and avoid significant harm to your body and unintentional disruption to the magnets.

If you have a nickel allergy, avoid contact with neodymium magnets.

Studies show a small percentage of people have allergies to certain metals, including nickel. An allergic reaction often manifests as skin redness and rash. If you have a nickel allergy, you can try wearing gloves or simply avoid direct contact with nickel-plated neodymium magnets.

Neodymium magnets can demagnetize at high temperatures.

Although magnets have demonstrated their effectiveness up to 80°C or 175°F, the temperature can vary depending on the type, shape, and intended use of the specific magnet.

Please read the article - What danger lies in neodymium magnets? You will learn how to handle them properly.

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e-mail: bok@dhit.pl

tel: +48 888 99 98 98