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SM 25x400 [2xM8] / N42 - magnetic roller

magnetic separator

catalog number 130365

GTIN: 5906301813392

no reviews

diameter Ø

25 mm [±0,1 mm]

height

400 mm [±0,1 mm]

max. temperature

≤ 80 °C

1131.60 ZŁ gross price (including VAT) / pcs +

920.00 ZŁ net price + 23% VAT / pcs

bulk discounts:

need more quantity?
price from 1 pcs
920.00 ZŁ
1131.60 ZŁ
price from 3 pcs
874.00 ZŁ
1075.02 ZŁ
price from 5 pcs
828.00 ZŁ
1018.44 ZŁ

Do you have questions?

Give us a call tel: +48 888 99 98 98 or write through form on the contact page. You can check the mass and the appearance of neodymium magnets in our force calculator magnetic calculator

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

Specification: magnetic separator 25x400 [2xM8] / N42

Characteristics: magnetic separator 25x400 [2xM8] / N42
Properties
Values
catalog number
130365
GTIN
5906301813392
production / distribution
Dhit sp. z o.o.
country of origin
Poland / China / Germany
customs code
85059029
diameter Ø
25 mm [±0,1 mm]
height
400 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 - 15 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 magnetic separator, namely the magnetic roller, uses the force of neodymium magnets, which are embedded in a casing made of stainless steel mostly AISI304. In this way, it is possible to efficiently separate ferromagnetic particles from other materials. 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 collected. The thickness of the embedded magnet and its structure's pitch affect the power and range of the separator's operation.
Generally speaking, magnetic separators are used to segregate ferromagnetic particles. If the cans are made of ferromagnetic materials, the separator will effectively segregate them. However, if the cans are made of non-ferromagnetic materials, such as aluminum, the separator will not be able to separate them.
Yes, magnetic rollers find application in food production for the elimination of metallic contaminants, such as iron fragments or iron dust. Our rollers are made from durable acid-resistant steel, EN 1.4301, intended for contact with food.
Magnetic rollers, otherwise magnetic separators, are used in food production, metal separation as well as recycling. They help in removing iron dust in the course of the process of separating metals from other materials.
Our magnetic rollers consist of neodymium magnets anchored in a stainless steel tube cylinder made of stainless steel with a wall thickness of 1mm.
Both ends of the magnetic bar can 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 forces, magnetic bars stand out in terms of magnetic force lines, flux density and the field of the magnetic field. We produce them in materials, N42 and N52.
Usually it is believed that the stronger the magnet, the better. However, 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 will be short. On the other hand, in the case of a thicker magnet, the force lines will be extended and reach further.
For creating the casings of magnetic separators - rollers, most often stainless steel is employed, especially types AISI 316, AISI 316L, and AISI 304.
In a salt water contact, AISI 316 steel is highly recommended due to its excellent anti-corrosion properties.
Magnetic bars 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 often use 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 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 result 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 rollers offer a range of benefits such as a very strong magnetic field, the ability to capture even the tiniest metal particles, and durability. On the other hand, among the drawbacks, one can mention higher cost compared to other types of magnets and the need for regular maintenance.
For proper maintenance of neodymium magnetic rollers, it is recommended they should be regularly cleaned, avoiding temperatures up to 80°C. The rollers feature waterproofing IP67, so if they are not sealed, the magnets inside can rust and weaken. Magnetic field measurements is recommended be carried out every two years. 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 cause problems with the magnetic rod seal and product contamination. The effective range of the roller is equal 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, which are used to remove metal contaminants from bulk and granular materials. They are used in the food industry, recycling, and plastic processing, where metal separation is crucial.

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Advantages and disadvantages of neodymium magnets NdFeB.

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

  • They do not lose strength over time - after 10 years, their power decreases by only ~1% (theoretically),
  • They are exceptionally resistant to demagnetization caused by an external magnetic field,
  • In other words, thanks to the shiny nickel, gold, or silver finish, the element gains an aesthetic appearance,
  • They possess very high magnetic induction on the surface of the magnet,
  • Magnetic neodymium magnets are characterized by very high magnetic induction on the surface of the magnet and can operate (depending on the form) even at temperatures of 230°C or higher...
  • The ability for precise shaping or customization to specific needs – neodymium magnets can be produced in many variants of shapes or sizes, which amplifies their universality in usage.
  • Key role in advanced technologically fields – find application in hard drives, electric drive mechanisms, medical equipment and other modern machines.

Disadvantages of neodymium magnets:

  • They are fragile when subjected to a powerful 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 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 form and height). However, we also offer special magnets with high temperature resistance, up to 230°C,
  • 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 - a magnetic holder is recommended due to the limited production capabilities of creating threads or complex shapes in the magnet
  • Health risk associated with microscopic parts of magnets pose a threat, when accidentally ingested, which is crucial in the context of children's health. Furthermore, miniscule components of these magnets can hinder the diagnostic process when they are in the body.

Safety Precautions

Neodymium magnets are over 10 times more powerful than ferrite magnets (the ones in speakers), and their power can shock you.

Familiarize yourself with our information to properly handle these magnets and avoid significant injuries to your body and prevent damage to the magnets.

Neodymium magnets can demagnetize at high temperatures.

Under specific conditions, Neodymium magnets can lose their magnetism when subjected to high temperatures.

Keep neodymium magnets away from GPS and smartphones.

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

Neodymium magnets are not recommended for people with pacemakers.

In the case of neodymium magnets, there is a strong magnetic field. As a result, it interferes 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.

Neodymium magnets are primarily characterized by their significant internal force. They attract to each other, and any object that comes in their way will be affected.

Magnets will jump and also contact together within a radius of several to almost 10 cm from each other.

  Neodymium magnets should not be in the vicinity 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.

Neodymium magnetic are incredibly fragile, they easily fall apart as well as can become damaged.

Magnets made of neodymium are extremely delicate, and by joining them in an uncontrolled manner, they will crumble. Neodymium magnetic are made of metal and coated with a shiny nickel, but they are not as durable as steel. At the moment of collision between the magnets, small metal fragments can be dispersed in different directions.

Keep neodymium magnets away from the wallet, computer, and TV.

Neodymium magnets produce intense magnetic fields that can destroy magnetic media such as floppy disks, video tapes, HDDs, credit cards, magnetic ID cards, cassette tapes, etc. devices. They can also damage devices like video players, televisions, CRT computer monitors. Do not forget to keep neodymium magnets at a safe distance from these electronic devices.

Dust and powder from neodymium magnets are highly flammable.

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

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 you are aware of why neodymium magnets are so dangerous, read the article titled How dangerous are strong neodymium magnets?.
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tel: +48 888 99 98 98