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neodymium magnets

We offer blue color magnets Nd2Fe14B - our offer. Practically all "neodymium magnets" in our store are available for immediate delivery (check the list). Check out the magnet price list for more details check the magnet price list

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SM 25x375 [2xM8] / N42 - magnetic roller

magnetic separator

catalog number 130351

GTIN: 5906301812999

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diameter Ø

25 mm [±0,1 mm]

height

375 mm [±0,1 mm]

max. temperature

≤ 80 °C

1057.80 gross price (including VAT) / pcs +

860.00 ZŁ net price + 23% VAT / pcs

bulk discounts:

need more quantity?

price from 1 pcs
860.00 ZŁ
1057.80 ZŁ
price from 3 pcs
817.00 ZŁ
1004.91 ZŁ
price from 6 pcs
774.00 ZŁ
952.02 ZŁ

Want to bargain?

Give us a call tel: +48 888 99 98 98 or write through form on the contact page. You can check the lifting capacity and the shape of neodymium magnet in our power calculator force calculator

Orders placed by 2:00 PM will be shipped on the same business day.

Specification: magnetic separator 25x375 [2xM8] / N42

Characteristics: magnetic separator 25x375 [2xM8] / N42
Properties
Values
catalog number
130351
production / distribution
Dhit sp. z o.o.
country of origin
Poland / China / Germany
customs code
85059029
diameter Ø
25 mm [±0,1 mm]
height
375 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 - 14 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, placed in a construction made of stainless steel usually AISI304. As a result, it is possible to precisely separate ferromagnetic particles from the mixture. A key aspect of its operation is the use of repulsion of N and S poles of neodymium magnets, which enables magnetic substances to be collected. The thickness of the embedded magnet and its structure pitch determine the power and range of the separator's operation.
Generally speaking, magnetic separators are used to separate ferromagnetic particles. 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 food production for the elimination of metallic contaminants, including iron fragments or iron dust. Our rods are made from acid-resistant steel, AISI 304, intended for contact with food.
Magnetic rollers, often called cylindrical magnets, are employed in metal separation, food production as well as waste processing. They help in extracting iron dust in the course of the process of separating metals from other wastes.
Our magnetic rollers are composed of neodymium magnets embedded in a stainless steel tube casing of stainless steel with a wall thickness of 1mm.
Both ends of the magnetic bar can be with M8 threaded holes - 18 mm, enabling simple mounting in machines or magnetic filter drawers. A "blind" version is also possible in manual separators.
In terms of forces, magnetic bars differ in terms of magnetic force lines, flux density and the area of operation of the magnetic field. We produce them in two materials, N42 as well as N52.
Generally it is believed that the greater the magnet's power, the more efficient it is. But, the value of the magnet's power depends on the height of the used magnet and the quality of the material [N42] or [N52], as well as on the area of application and expected needs. The standard operating temperature of a magnetic bar is 80°C.
If the magnet is thin, the magnetic force lines will be more compressed. Otherwise, when the magnet is thick, the force lines will be extended and reach further.
For constructing the casings of magnetic separators - rollers, usually stainless steel is utilized, especially types AISI 304, AISI 316, and AISI 316L.
In a salt water contact, AISI 316 steel exhibits the best resistance thanks to its excellent anti-corrosion properties.
Magnetic rollers are characterized by their unique configuration of poles and their capability to attract magnetic particles directly onto their surface, in contrast to other separators that often use complex filtration systems.
Technical designations and terms pertaining to magnetic separators include amongst others magnet pitch, polarity, and magnetic induction, 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, seeking the highest magnetic field value close to the magnetic pole. The outcome is checked in a value table - the lowest is N30. All designations below N27 or N25 indicate recycling that falls below the standard - they are not suitable.
Neodymium magnetic rollers offer many advantages, including higher attracting power, longer lifespan, and effectiveness in separating fine metal particles. Disadvantages may include higher cost compared to other types of magnets and the need for regular maintenance.
By ensuring proper maintenance of neodymium magnetic rollers, it is recommended cleaning regularly, avoiding temperatures up to 80°C. The rollers feature waterproofing IP67, so if they are not sealed, the magnets inside can oxidize and lose their power. Testing of the rollers is recommended be carried out once every 24 months. Caution should be taken during use, as it’s possible of finger injury. If the protective tube is only 0.5 mm thick, it may wear out, which in turn could lead to problems with the magnetic rod seal and product contamination. The effective range of the roller corresponds to its diameter: fi25mm gives an active range of about 25mm, while fi32 gives an active range of about 40mm.
A magnetic roller is a magnetic separator made from a neodymium magnet enclosed in a cylindrical stainless steel housing, used for separating ferromagnetic contaminants from raw materials. They are used in the food industry, recycling, and plastic processing, where the removal of iron metals and iron filings is essential.

Find suggested articles

Advantages as well as disadvantages of neodymium magnets NdFeB.

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

  • They do not lose their strength (of the magnet). After about 10 years, their power decreases by only ~1% (theoretically),
  • They are highly resistant to demagnetization by external magnetic field,
  • In other words, thanks to the shiny nickel, gold, or silver finish, the element gains an aesthetic appearance,
  • They exhibit very high magnetic induction on the surface of the magnet,
  • Thanks to their high temperature resistance, they can operate (depending on the shape) even at temperatures up to 230°C and above...
  • Due to the option of accurate forming or adaptation to individual needs – neodymium magnets can be produced in many variants of shapes or sizes, which amplifies their universality in usage.
  • Key role in modern technologies – are used in computer drives, electric motors, medical equipment or other advanced devices.

Disadvantages of neodymium magnets:

  • They are fragile when subjected to a strong impact. If the magnets are exposed to impacts, we recommend using magnets in a protective case. The steel housing in the form of a holder protects the magnet from impacts, and at the same time increases its overall strength,
  • They lose strength at high temperatures. Most neodymium magnets experience permanent loss of strength when heated above 80°C (depending on the shape and height). However, we also offer special magnets with high temperature resistance, up to 230°C,
  • Due to their susceptibility to corrosion in a humid environment, we suggest using waterproof magnets made of rubber, plastic, or other moisture-resistant materials when using them outdoors,
  • The use of a cover - a magnetic holder is recommended due to the limited production capabilities of creating threads or complex shapes in the magnet
  • Potential hazard associated with microscopic parts of magnets are risky, if swallowed, which becomes significant in the aspect of protecting young children. It's also worth noting that small elements of these products are able to complicate diagnosis after entering the body.

Exercise Caution with Neodymium Magnets

Do not bring neodymium magnets close to GPS and smartphones.

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

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

Studies clearly indicate a small percentage of people who suffer from metal allergies such as 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.

People with pacemakers are advised to avoid neodymium magnets.

Neodymium magnets generate very strong magnetic fields that can interfere with the operation of a pacemaker. This is because many of these devices are equipped with a function that deactivates the device in a magnetic field.

Magnets made of neodymium are incredibly delicate, they easily fall apart and can become damaged.

In the event of a collision between two neodymium magnets, it can result in them getting chipped. Despite being made of metal and 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 placed near a computer HDD, TV, and wallet.

Strong fields generated by neodymium magnets can damage magnetic storage media such as floppy disks, credit cards, magnetic ID cards, cassette tapes, video tapes, or other similar devices. In addition, they can damage televisions, VCRs, computer monitors, and CRT displays. Avoid placing neodymium magnets in close proximity to electronic devices.

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

Magnets may crack or crumble with careless joining to each other. You can't approach them to each other. At a distance less than 10 cm you should have them very strongly.

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.

  Magnets are not toys, children should not play with them.

Remember that neodymium magnets are not toys. Do not allow children to play with them. In the case of swallowing multiple magnets simultaneously, they can attract to each other through the intestinal walls. In the worst case scenario, this can lead to death.

Comparing neodymium magnets to ferrite magnets (found in speakers), they are 10 times more powerful, and their power 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 damage to the magnets.

Dust and powder from neodymium magnets are highly 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.

So you are aware of why neodymium magnets are so dangerous, see the article titled How very dangerous are very powerful neodymium magnets?.

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e-mail: bok@dhit.pl

tel: +48 888 99 98 98