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neodymium magnets

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SM 25x275 [2xM8] / N42 - magnetic roller

magnetic separator

catalog number 130294

GTIN: 5906301812876

5.0

diameter Ø

25 mm [±0,1 mm]

height

275 mm [±0,1 mm]

max. temperature

≤ 80 °C

762.60 ZŁ gross price (including VAT) / pcs +

620.00 ZŁ net price + 23% VAT / pcs

bulk discounts:

need more quantity?
price from 1 pcs
620.00 ZŁ
762.60 ZŁ
price from 4 pcs
589.00 ZŁ
724.47 ZŁ
price from 8 pcs
558.00 ZŁ
686.34 ZŁ

Do you have a dilemma in choosing?

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

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

Specification: magnetic separator 25x275 [2xM8] / N42

Characteristics: magnetic separator 25x275 [2xM8] / N42
Properties
Values
catalog number
130294
GTIN
5906301812876
production / distribution
Dhit sp. z o.o.
country of origin
Poland / China / Germany
customs code
85059029
diameter Ø
25 mm [±0,1 mm]
height
275 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 - 10 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 power of neodymium magnets, which are embedded in a casing made of stainless steel usually AISI304. Due to this, it is possible to precisely remove ferromagnetic particles from other materials. An important element of its operation is the use of repulsion of magnetic poles N and S, which enables magnetic substances to be targeted. The thickness of the magnet and its structure's pitch determine the range and strength of the separator's operation.
Generally speaking, magnetic separators serve to segregate ferromagnetic elements. If the cans are ferromagnetic, the separator will effectively segregate 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 sector to clear metallic contaminants, such as iron fragments or iron dust. Our rollers are made from acid-resistant steel, AISI 304, approved for use in food.
Magnetic rollers, often called magnetic separators, are employed 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 a neodymium magnet anchored in a stainless steel tube casing made of stainless steel with a wall thickness of 1mm.
Both ends of the magnetic bar will be with M8 threaded openings, allowing for 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 materials, N42 as well as N52.
Usually it is believed that the greater the magnet's power, the more effective. But, 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 thin, the magnetic force lines are more compressed. On the other hand, when the magnet is thick, the force lines are longer and extend over a greater distance.
For making the casings of magnetic separators - rollers, usually stainless steel is used, particularly types AISI 316, AISI 316L, and AISI 304.
In a saltwater contact, type AISI 316 steel exhibits the best resistance thanks to its excellent corrosion resistance.
Magnetic rollers are characterized by their unique configuration of poles and their capability to attract magnetic particles directly onto their surface, as opposed to other devices that often use more complicated filtration systems.
Technical designations and terms pertaining to magnetic separators comprise among others magnet pitch, polarity, and magnetic induction, as well as the steel type applied.
Magnetic induction for a roller is determined using a teslameter or a gaussmeter with a flat Hall-effect probe, aiming to find the highest magnetic field value near the magnetic pole. The outcome is checked in a value table - the lowest is N30. All designations less than N27 or N25 indicate recycling that doesn't meet 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. 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, you should cleaning after each use, avoiding temperatures above 80 degrees. The rollers feature waterproofing IP67, so if they are leaky, the magnets inside can rust and lose their power. Testing of the rollers is recommended be carried out once every 24 months. Care should be taken, 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 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.
Magnetic rollers are cylindrical neodymium magnets placed in a casing made of corrosion-resistant stainless steel, used for separating ferromagnetic contaminants from raw materials. They are used in the food industry, recycling, and plastic processing, where metal separation is crucial.

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Advantages as well as disadvantages of neodymium magnets NdFeB.

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

  • They do not lose their power (of the magnet). After about 10 years, their strength decreases by only ~1% (theoretically),
  • They are highly resistant to demagnetization by external magnetic sources,
  • In other words, thanks to the shiny coating of nickel, gold, or silver, the element acquires an aesthetic appearance,
  • They exhibit extremely high magnetic induction on the surface of the magnet,
  • Magnetic neodymium magnets are characterized by hugely high magnetic induction on the surface of the magnet and can operate (depending on the shape) even at temperatures of 230°C or higher...
  • The ability for precise shaping and customization to specific needs – neodymium magnets can be produced in various forms and dimensions, which enhances their versatility in applications.
  • Key role in modern technologies – are used in computer drives, electric drive mechanisms, medical equipment and other highly developed apparatuses.

Disadvantages of neodymium magnets:

  • They can break 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,
  • Magnets lose their power 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
  • Possible danger arising from small pieces of magnets are risky, when accidentally ingested, which is crucial in the context of child safety. Furthermore, small elements of these magnets are able to complicate diagnosis after entering the body.

Handle Neodymium Magnets with Caution

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. They can also damage televisions, VCRs, computer monitors, and CRT displays. Avoid placing neodymium magnets in close proximity to electronic devices.

The magnet is coated with nickel - be careful if you have an allergy.

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, try wearing gloves or avoid direct contact with nickel-plated neodymium magnets.

Keep neodymium magnets away from 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.

 It is essential to maintain neodymium magnets out of reach from children.

Neodymium magnets are not toys. Be cautious and make sure no child plays 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.

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.

Neodymium magnets can attract to each other, pinch the skin, and cause significant injuries.

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

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

On our website, you can find information on how to use neodymium magnets. This will help you avoid injuries and prevent damage to the magnets.

Neodymium magnetic are fragile and can easily break and get damaged.

Neodymium magnetic are highly fragile, and by joining them in an uncontrolled manner, they will break. Neodymium magnets are made of metal and coated with a shiny nickel surface, but they are not as hard 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.

Neodymium magnets can become demagnetized at high temperatures.

Although magnets have shown to retain their effectiveness up to 80°C or 175°F, this temperature may vary depending on the type of material, shape, and intended use of the magnet.

Keep neodymium magnets away from people with pacemakers.

Neodymium magnets generate strong magnetic fields. As a result, they 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.

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