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

magnetic separator

Catalog no 130293

GTIN: 5906301812869

5

Diameter Ø [±0,1 mm]

25 mm

Height [±0,1 mm]

250 mm

Weight

0.01 g

688.80 with VAT / pcs + price for transport

560.00 ZŁ net + 23% VAT / pcs

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

Specification/characteristics SM 25x250 [2xM8] / N42 - magnetic separator
properties
values
Cat. no.
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]
Weight
0.01 g [±0,1 mm]
Manufacturing Tolerance
± 0.1 mm

Magnetic properties of material N42

properties
values
units
coercivity bHc ?
860-955
kA/m
coercivity bHc ?
10.8-12.0
kOe
energy density [Min. - Max.] ?
318-334
BH max KJ/m
energy density [Min. - Max.] ?
40-42
BH max MGOe
remenance Br [Min. - Max.] ?
12.9-13.2
kGs
remenance Br [Min. - Max.] ?
1290-1320
T
actual internal force iHc
≥ 955
kA/m
actual internal force iHc
≥ 12
kOe
max. temperature ?
≤ 80
°C

Physical properties of NdFeB

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

Shopping tips

The magnetic separator, namely the magnetic roller, uses the force of neodymium magnets, placed in a casing made of stainless steel usually AISI304. As a result, it is possible to effectively remove ferromagnetic particles from different substances. An important element of its operation is the repulsion of magnetic poles N and S, which causes magnetic substances to be attracted. The thickness of the magnet and its structure pitch affect the range and strength of the separator's operation.
Generally speaking, magnetic separators serve to separate ferromagnetic particles. If the cans are made from 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 used in the food industry to clear metallic contaminants, including iron fragments or iron dust. Our rods are constructed from durable acid-resistant steel, AISI 304, approved for use in food.
Magnetic rollers, otherwise cylindrical magnets, find application in food production, metal separation as well as waste processing. They help in eliminating iron dust in the course of the process of separating metals from other materials.
Our magnetic rollers consist of a neodymium magnet placed in a stainless steel tube cylinder made of stainless steel with a wall thickness of 1mm.
From both sides of the magnetic bar will be with M8 threaded holes - 18 mm, 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 flux density, magnetic force lines and the field of the magnetic field. We produce them in two materials, N42 as well as N52.
Usually it is believed that the stronger the magnet, the better. Nevertheless, the strength of the magnet's power is based 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.
When the magnet is thin, the magnetic force lines are more compressed. By contrast, in the case of a thicker magnet, the force lines will be longer and extend over a greater distance.
For making the casings of magnetic separators - rollers, frequently stainless steel is utilized, especially types AISI 304, AISI 316, and AISI 316L.
In a salt water contact, type AISI 316 steel is highly recommended thanks to its outstanding corrosion resistance.
Magnetic bars are characterized by their unique configuration of poles and their ability 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 amongst others polarity, magnetic induction, magnet pitch, as well as the type of steel used.
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 near the magnetic pole. The result is verified in a value table - the lowest is N30. All designations below N27 or N25 indicate 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.
By ensuring proper maintenance of neodymium magnetic rollers, it is recommended they should be regularly cleaned, avoiding temperatures up to 80°C. The rollers our rollers have waterproofing IP67, so if they are leaky, the magnets inside can rust and weaken. Testing of the rollers should be carried out once every 24 months. Care should be taken, as it’s possible getting pinched. 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 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, which are used to remove metal contaminants from bulk and granular materials. They are applied in industries such as food processing, ceramics, and recycling, where metal separation is crucial.

Advantages and disadvantages of neodymium magnets NdFeB.

In addition to their magnetic efficiency, neodymium magnets provide the following advantages:

  • They virtually do not lose power, because even after 10 years, the performance loss is only ~1% (according to literature),
  • They remain magnetized despite exposure to strong external fields,
  • Because of the lustrous layer of nickel, the component looks visually appealing,
  • The outer field strength of the magnet shows elevated magnetic properties,
  • They are suitable for high-temperature applications, operating effectively at 230°C+ due to advanced heat resistance and form-specific properties,
  • The ability for custom shaping as well as customization to specific needs – neodymium magnets can be manufactured in a wide range of shapes and sizes, which amplifies their functionality across industries,
  • Key role in new technology industries – they are utilized in HDDs, rotating machines, diagnostic apparatus or even other advanced devices,
  • Relatively small size with high magnetic force – neodymium magnets offer impressive pulling strength in small dimensions, which allows for use in compact constructions

Disadvantages of neodymium magnets:

  • They may fracture when subjected to a powerful impact. If the magnets are exposed to shocks, it is suggested to place them in a metal holder. The steel housing, in the form of a holder, protects the magnet from cracks while also reinforces its overall durability,
  • Magnets lose field strength when exposed to temperatures exceeding 80°C. In most cases, this leads to irreversible power drop (influenced by the magnet’s profile). To address this, we provide [AH] models with superior thermal resistance, able to operate even at 230°C or more,
  • Due to corrosion risk in humid conditions, it is advisable to use sealed magnets made of synthetic coating for outdoor use,
  • Using a cover – such as a magnetic holder – is advised due to the restrictions in manufacturing complex structures directly in the magnet,
  • Potential hazard due to small fragments may arise, if ingested accidentally, which is notable in the protection of children. Moreover, tiny components from these products have the potential to disrupt scanning if inside the body,
  • High unit cost – neodymium magnets are more expensive than other types of magnets (e.g., ferrite), which can restrict large-scale applications

Exercise Caution with Neodymium Magnets

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.

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

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.

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 magnetic are particularly delicate, resulting in damage.

Magnets made of neodymium are extremely fragile, and by joining them in an uncontrolled manner, they will crack. 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.

 It is important to keep neodymium magnets out of reach from children.

Remember that neodymium magnets are not toys. Be cautious and make sure no child plays with them. Small magnets can pose a serious choking hazard. If multiple magnets are swallowed, they can attract to each other through the intestinal walls, causing significant injuries, and even death.

Keep neodymium magnets away from 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. However, if the magnetic field does not affect the device, it can damage its components or deactivate the device when it is in a magnetic field.

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

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

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

Neodymium magnets are a source of intense magnetic fields that cause interference with magnetometers and compasses used in navigation, as well as internal compasses of smartphones and GPS devices.

Neodymium magnets are the strongest magnets ever invented. Their power can surprise you.

Familiarize yourself with our information to correctly handle these magnets and avoid significant swellings to your body and prevent disruption to the magnets.

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.

If the joining of neodymium magnets is not under control, then they may crumble and crack. Remember not to approach them to each other or have them firmly in hands at a distance less than 10 cm.

Caution!

In order for you to know how powerful neodymium magnets are and why they are so dangerous, see the article - Dangerous very powerful neodymium magnets.

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tel: +48 888 99 98 98