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neodymium magnets

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

magnetic separator

catalog number 130293

GTIN: 5906301812869

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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Want to talk about magnets?

Call us tel: +48 888 99 98 98 or contact us through contact form on the contact page. You can check the power as well as the appearance of neodymium magnets in our magnetic mass calculator magnetic mass calculator

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

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

Characteristics: magnetic separator 25x250 [2xM8] / N42
Properties
Values
catalog number
130293
GTIN
5906301812869
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 placed in a casing made of stainless steel usually AISI304. In this way, it is possible to precisely segregate ferromagnetic particles from different substances. 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 attracted. 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 are used to separate ferromagnetic particles. If the cans are made from ferromagnetic materials, a magnetic separator will be effective. 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 are employed in food production for the elimination of metallic contaminants, such as iron fragments or iron dust. Our rollers are built from durable acid-resistant steel, AISI 304, intended for use in food.
Magnetic rollers, often called cylindrical magnets, find application in metal separation, food production as well as waste processing. They help in extracting iron dust during the process of separating metals from other materials.
Our magnetic rollers are composed of neodymium magnets placed 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 holes - 18 mm, which enables simple mounting 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 materials, N42 and N52.
Often it is believed that the stronger the magnet, the more efficient it is. However, 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 use and anticipated 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 more compressed. On the other hand, when the magnet is thick, the force lines will be extended and extend over a greater distance.
For making 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 outstanding anti-corrosion properties.
Magnetic bars stand out for their unique configuration of poles and their ability to attract magnetic particles directly onto their surface, in contrast to other devices that may utilize more complicated filtration systems.
Technical designations and terms related to magnetic separators include among others polarity, magnetic induction, magnet pitch, as well as the type of steel used.
Magnetic induction for a roller is measured using a teslameter or a gaussmeter with a flat Hall-effect probe, seeking 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 suggest recycling that doesn't meet the standard - they are not suitable.
Neodymium magnetic rollers offer a range of benefits such as higher attracting power, longer lifespan, and effectiveness in separating fine metal particles. However, some of the downsides may involve the need for regular cleaning, higher cost, and potential installation challenges.
For proper maintenance of neodymium magnetic rollers, it is advised to clean them regularly from deposits, avoid extremal temperatures up to 80°C, and washing regularly, avoiding temperatures up to 80°C. The rollers our rollers have an IP67 waterproof rating, so if they are not sealed, the magnets inside may oxidize and lose their strength. Roller inspections are advised 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 wear out, which, in turn, may lead to 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 strength, neodymium magnets have the following advantages:

  • They do not lose strength over time. After 10 years, their strength decreases by only ~1% (theoretically),
  • They protect against demagnetization caused by external magnetic field extremely well,
  • In other words, thanks to the shiny coating of nickel, gold, or silver, the element acquires 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 various forms and dimensions, which enhances their versatility in applications.
  • Wide application in advanced technologically fields – are used in HDD drives, electric drive mechanisms, medical devices or other modern machines.

Disadvantages of neodymium magnets:

  • They can break as they are extremely fragile when subjected to a strong impact. If the magnets are exposed to impacts, it is suggested using magnets in a metal holder. The steel housing in the form of a holder protects the magnet from impacts and simultaneously increases its overall strength,
  • High temperatures can reduce the strength of neodymium magnets. Typically, after heating above 80°C, most of them experience a permanent loss 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,
  • 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,
  • Limited ability to create threads or complex shapes in the magnet - the use of a housing is recommended - magnetic holder
  • Potential hazard to health from tiny fragments of magnets are risky, if swallowed, which becomes significant in the context of child safety. Furthermore, small elements of these products have the potential to complicate diagnosis after entering the body.

Caution with Neodymium Magnets

  Neodymium magnets should not be around youngest children.

Neodymium magnets are not toys. Do not allow children to play with them. They can be a significant choking hazard. If multiple magnets are swallowed, they can attract to each other through the intestinal walls, causing significant injuries, and even death.

Neodymium magnets can demagnetize at high temperatures.

While Neodymium magnets can demagnetize at high temperatures, it's important to note that the extent of this effect can vary based on factors such as the magnet's material, shape, and intended application.

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.

People with pacemakers are advised to avoid neodymium magnets.

Neodymium magnets generate strong magnetic fields. As a result, they interfere with the operation of a pacemaker. This happens because such devices have a function to deactivate them in a magnetic field.

Neodymium magnets are extremely fragile, leading to breaking.

Neodymium magnets are fragile as well as will shatter if allowed to collide with each other, even from a distance of a few centimeters. Despite being made of metal and coated with a shiny nickel plating, they are not as hard as steel. At the moment of collision between the magnets, small sharp metal fragments can be propelled in various directions at high speed. Eye protection is recommended.

Under no circumstances should neodymium magnets be placed 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 devices like video players, televisions, CRT computer monitors. Remember not to place neodymium magnets close to these electronic devices.

Neodymium magnets are the most powerful magnets ever created, and their power can surprise 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.

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.

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.

If the joining of neodymium magnets is not controlled, then they may crumble and also crack. You can't move them to each other. At a distance less than 10 cm you should hold them extremely strongly.

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.

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