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neodymium magnets

We provide blue color magnets Nd2Fe14B - our proposal. Practically all "neodymium magnets" on our website are available for immediate purchase (see the list). Check out the magnet pricing for more details see the magnet price list

Magnets for water searching F400 GOLD

Where to buy strong neodymium magnet? Magnetic holders in airtight and durable enclosure are perfect for use in variable and difficult weather conditions, including in the rain and snow see more...

magnets with holders

Magnetic holders can be used to improve manufacturing, exploring underwater areas, or searching for meteorites made of ore see more...

Enjoy delivery of your order if the order is placed before 2:00 PM on weekdays.

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SM 25x300 [2xM8] / N42 - magnetic roller

magnetic separator

catalog number 130295


diameter Ø

25 mm


300 mm

max. temperature

≤ 80 °C

836.40 PLN gross price (including VAT) / pcs +

680.00 PLN net price + 23% VAT / pcs

bulk discounts:

need more quantity?

price from 1 pcs
680.00 PLN
836.40 PLN
price from 4 pcs
646.00 PLN
794.58 PLN
price from 7 pcs
612.00 PLN
752.76 PLN

Want a better price?

Give us a call tel: +48 22 499 98 98 or get in touch via form on our website. You can check the strength as well as the appearance of neodymium magnets in our power calculator magnetic mass calculator

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

Specification: magnetic separator 25x300 [2xM8] / N42

Characteristics: magnetic separator 25x300 [2xM8] / N42
production / distribution
Dhit sp. z o.o.
country of origin
Poland / China / Germany
customs code
diameter Ø ?
25 mm
height ?
300 mm
max. temperature ?
≤ 80 °C
0.01 g
execution tolerance
± 0.1 mm
rodzaj materiału
AISI 304 - bezpieczna dla żywności
rodzaj magnesów
NdFeB N42
ilość gwintów
2x [M8] wewnętrzne
obwodowa - 11 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
remenance Br [Min. - Max.] ?
remenance Br [Min. - Max.] ?
coercivity bHc ?
coercivity bHc ?
actual internal force iHc
≥ 12
actual internal force iHc
≥ 955
energy density [Min. - Max.]
BH max MGOe
energy density [Min. - Max.]
BH max KJ/m
max. temperature
≤ 80

Physical properties of sintered neodymium magnets Nd2Fe14B

Physical properties of sintered neodymium magnets Nd2Fe14B
Vickers hardness
Curie Temperature TC
312 - 380
Curie Temperature TF
593 - 716
Specific resistance
Bending strength
Compressive strength
Thermal expansion parallel (∥) to orientation (M)
(3-4) x 106
Thermal expansion perpendicular (⊥) to orientation (M)
-(1-3) x 10-6
Young's modulus
1.7 x 104
The device rod magnetic is based on the use of neodymium magnets, which are embedded in a construction made of stainless steel usually AISI304. Due to this, it is possible to efficiently separate ferromagnetic particles from other materials. A key aspect of its operation is the use of repulsion of magnetic poles N and S, which allows magnetic substances to be attracted. The thickness of the magnet and its structure pitch determine the power and range of the separator's operation.
Generally speaking, magnetic separators serve to separate ferromagnetic particles. If the cans are ferromagnetic, a magnetic separator will be effective. However, if the cans are made of non-ferromagnetic materials, such as aluminum, the separator will not effectively segregate them.
Yes, magnetic rollers are used in the food sector to clear metallic contaminants, including iron fragments or iron dust. Our rollers are constructed from durable acid-resistant steel, EN 1.4301, suitable for contact with food.
Magnetic rollers, otherwise cylindrical magnets, are used in food production, metal separation as well as recycling. They help in removing iron dust during the process of separating metals from other materials.
Our magnetic rollers consist of neodymium magnets placed in a tube of stainless steel with a wall thickness of 1mm.
From both sides of the magnetic bar can be with M8 threaded openings, enabling quick installation in machines or magnetic filter drawers. A "blind" version is also possible in manual separators.
In terms of magnetic properties, magnetic bars stand out in terms of flux density, magnetic force lines 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 better. But, the strength 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 use and expected needs. The standard operating temperature of a magnetic bar is 80°C.
In the case where the magnet is more flat, the magnetic force lines are short. On the other hand, when the magnet is thick, the force lines are extended and extend over a greater distance.
For constructing the casings of magnetic separators - rollers, frequently stainless steel is utilized, especially types AISI 316, AISI 316L, and AISI 304.
In a saltwater contact, AISI 316 steel exhibits the best resistance thanks to its outstanding anti-corrosion properties.
Magnetic rollers are characterized by their unique configuration of poles and their capability to attract magnetic substances directly onto their surface, as opposed to other separators that may utilize more complicated filtration systems.
Technical designations and terms related to magnetic separators include among others magnet pitch, polarity, and magnetic induction, as well as the steel type applied.
Magnetic induction for a magnet on a roller is measured 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 result is checked in a value table - the lowest is N30. All designations less than N27 or N25 suggest recycling that doesn't meet the standard - they are not suitable.
Neodymium magnetic rollers offer a range of benefits such as a very strong magnetic field, the ability to capture even the tiniest metal particles, and durability. However, some of the downsides may involve higher cost compared to other types of magnets and the need for regular maintenance.
To properly maintain of neodymium magnetic rollers, it is suggested {to clean them regularly from deposits, avoid extremal temperatures above 80 degrees, and cleaning after each use, avoiding temperatures above 80 degrees. The rollers our rollers have an IP67 waterproof rating, so if they are not sealed, the magnets inside may oxidize and lose their strength. Magnetic field measurements are recommended to be conducted once every 24 months. Caution should be exercised during use as there is a risk 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.

In addition to immense strength, neodymium magnets have the following advantages:

  • They do not lose power over time - after about 10 years, their strength decreases by only ~1% (theoretically),
  • They protect against demagnetization caused by external magnetic sources extremely well,
  • 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,
  • By using an appropriate combination of materials, they can achieve high thermal resistance, allowing them to operate at temperatures up to 230°C and above...
  • Due to the option of accurate forming and adaptation to individual needs – neodymium magnets can be produced in many variants of shapes and sizes, which expands the range of their possible uses.
  • Significant importance in the industry of new technologies – find application in HDD drives, electric motors, medical devices or very highly developed apparatuses.

Disadvantages of neodymium magnets:

  • They can break when subjected to a powerful 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,
  • Magnets lose their strength due to exposure to high temperatures. In most cases, when the temperature exceeds 80°C, these magnets experience permanent loss in strength (although it is worth noting that this is dependent on the form and size of the magnet). To avoid this problem, we offer special magnets marked with the [AH] symbol, which exhibit high temperature resistance. They can operate even at temperatures as high as 230°C or more,
  • Magnets exposed to a humid environment can corrode. Therefore, when using them outdoors, we suggest using waterproof magnets made of rubber, plastic, or other moisture-resistant materials,
  • 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
  • Health risk associated with microscopic parts of magnets pose a threat, when accidentally ingested, which is particularly important in the context of children's health. Additionally, miniscule components of these devices are able to complicate diagnosis after entering the body.

Exercise Caution with Neodymium Magnets

Neodymium magnets can demagnetize at high temperatures.

Despite the general resilience of magnets, their ability to retain their magnetic strength can be influenced by factors like the type of material used, the magnet's shape, and the intended purpose for which it is employed.

Comparing neodymium magnets to ferrite magnets (found in speakers), they are 10 times stronger, and their power can shock you.

To handle magnets properly, it is best to familiarize yourself with our information beforehand. This will help you avoid significant harm to your body and the magnets themselves.

 Keep neodymium magnets far from 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.

You should maintain neodymium magnets at a safe distance from the wallet, computer, and TV.

The strong magnetic field generated by neodymium magnets can damage magnetic media such as floppy disks, video tapes, HDDs, credit cards, magnetic ID cards, cassette tapes, or other devices. They can also damage devices like video players, televisions, CRT computer monitors. Remember not to place neodymium magnets close to these electronic devices.

Magnets made of neodymium are delicate and can easily crack as well as get damaged.

Neodymium magnetic are extremely delicate, and by joining them in an uncontrolled manner, they will crumble. Magnets made of neodymium are made of metal and coated with a shiny nickel, but they are not as durable as steel. In the event of a collision between two magnets, there may be a scattering of fragments in different directions. Protecting your eyes is crucial in such a situation.

Dust and powder from neodymium magnets are flammable.

Avoid drilling or mechanical processing of neodymium magnets. If the magnet is crushed into fine powder or dust, it becomes highly flammable.

It is crucial not to allow the magnets to pinch together uncontrollably or place your fingers in their path as they attract to each other.

Magnets will attract each other within a distance of several to around 10 cm from each other. Remember not to insert fingers between magnets or in their path when they attract. Depending on how massive the neodymium magnets are, they can lead to a cut or alternatively a fracture.

Keep neodymium magnets away from people with pacemakers.

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.

Keep neodymium magnets as far away as possible from GPS and smartphones.

Neodymium magnets produce strong magnetic fields that interfere with magnetometers and compasses used in navigation, as well as internal compasses of smartphones and GPS devices.

The magnet is coated with nickel. Therefore, exercise caution if you have an allergy.

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.

So that know how strong neodymium magnets are and why they are so dangerous, read the article - Dangerous very powerful neodymium magnets.

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tel: +48 888 99 98 98