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SM 18x250 [2xM5] / N42 - magnetic separator

magnetic separator

Catalog no 130275

GTIN: 5906301812777

0

Diameter Ø [±0,1 mm]

18 mm

Height [±0,1 mm]

250 mm

Weight

0.01 g

553.50 with VAT / pcs + price for transport

450.00 ZŁ net + 23% VAT / pcs

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SM 18x250 [2xM5] / N42 - magnetic separator

Specification/characteristics SM 18x250 [2xM5] / N42 - magnetic separator
properties
values
Cat. no.
130275
GTIN
5906301812777
Production/Distribution
Dhit sp. z o.o.
Country of origin
Poland / China / Germany
Customs code
85059029
Diameter Ø
18 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
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 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 power of neodymium magnets, which are welded in a casing made of stainless steel usually AISI304. In this way, it is possible to precisely separate ferromagnetic particles from the mixture. An important element of its operation is the use of repulsion of magnetic poles N and S, which enables magnetic substances to be collected. The thickness of the embedded magnet and its structure pitch affect the range and strength of the separator's operation.
Generally speaking, magnetic separators serve to extract ferromagnetic particles. If the cans are made of ferromagnetic materials, the separator will be able to separate them. However, if the cans are made of non-ferromagnetic materials, such as aluminum, the magnetic separator will not be effective.
Yes, magnetic rollers find application in food production to clear metallic contaminants, including iron fragments or iron dust. Our rollers are constructed from acid-resistant steel, AISI 304, suitable for use in food.
Magnetic rollers, otherwise 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 built with a neodymium magnet embedded in a stainless steel tube casing made of stainless steel with a wall thickness of 1mm.
From both sides of the magnetic bar will be with M8 threaded openings, which enables quick installation in machines or magnetic filter drawers. A "blind" version is also possible in manual separators.
In terms of magnetic properties, magnetic bars differ in terms of flux density, magnetic force lines and the area of operation of the magnetic field. We produce them in two materials, N42 and N52.
Usually it is believed that the stronger the magnet, the more effective. 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 application and specific needs. The standard operating temperature of a magnetic bar is 80°C.
In the case where the magnet is thin, the magnetic force lines are short. On the other hand, when the magnet is thick, the force lines are longer and reach further.
For making the casings of magnetic separators - rollers, most often stainless steel is employed, particularly types AISI 304, AISI 316, and AISI 316L.
In a saltwater environment, type AISI 316 steel is highly recommended due to its outstanding anti-corrosion properties.
Magnetic bars stand out for their specific arrangement of poles and their capability to attract magnetic particles directly onto their surface, in contrast to other separators that may utilize complex filtration systems.
Technical designations and terms pertaining to magnetic separators comprise among 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, 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 suggest recycling that falls below the standard - they are not suitable.
Neodymium magnetic bars offer a range of benefits such as excellent separation efficiency, strong magnetic field, and durability. Disadvantages may include 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 above 80 degrees. The rollers our rollers have 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 every two years. 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, used for separating ferromagnetic contaminants from raw materials. They are applied in industries such as food processing, ceramics, and recycling, where the removal of iron metals and iron filings is essential.

Advantages and disadvantages of neodymium magnets NdFeB.

Besides their durability, neodymium magnets are valued for these benefits:

  • Their magnetic field is durable, and after around ten years, it drops only by ~1% (theoretically),
  • Their ability to resist magnetic interference from external fields is impressive,
  • In other words, due to the glossy nickel coating, the magnet obtains an stylish appearance,
  • They have very high magnetic induction on the surface of the magnet,
  • These magnets tolerate elevated temperatures, often exceeding 230°C, when properly designed (in relation to build),
  • Thanks to the flexibility in shaping and the capability to adapt to individual requirements, neodymium magnets can be created in various configurations, which broadens their application range,
  • Key role in cutting-edge sectors – they serve a purpose in hard drives, rotating machines, healthcare devices or even sophisticated instruments,
  • Compactness – despite their small size, they generate strong force, making them ideal for precision applications

Disadvantages of neodymium magnets:

  • They may fracture when subjected to a sudden impact. If the magnets are exposed to shocks, it is suggested to place them in a protective case. The steel housing, in the form of a holder, protects the magnet from damage , and at the same time enhances its overall robustness,
  • They lose power at extreme temperatures. Most neodymium magnets experience permanent degradation in strength when heated above 80°C (depending on the form and height). However, we offer special variants with high temperature resistance that can operate up to 230°C or higher,
  • They rust in a damp environment – during outdoor use, we recommend using moisture-resistant magnets, such as those made of plastic,
  • Limited ability to create internal holes in the magnet – the use of a housing is recommended,
  • Potential hazard due to small fragments may arise, if ingested accidentally, which is significant in the protection of children. It should also be noted that minuscule fragments from these assemblies have the potential to complicate medical imaging when ingested,
  • Due to the price of neodymium, their cost is above average,

Maximum lifting capacity of the magnetwhat it depends on?

The given pulling force of the magnet represents the maximum force, determined in ideal conditions, that is:

  • using a steel plate with low carbon content, acting as a magnetic circuit closure
  • of a thickness of at least 10 mm
  • with a refined outer layer
  • with zero air gap
  • with vertical force applied
  • under standard ambient temperature

Practical aspects of lifting capacity – factors

The lifting capacity of a magnet is determined by in practice the following factors, from primary to secondary:

  • Air gap between the magnet and the plate, as even a very small distance (e.g. 0.5 mm) causes a drop in lifting force of up to 50%.
  • Direction of applied force, because the maximum lifting capacity is achieved under perpendicular application. The force required to slide the magnet along the plate is usually several times lower.
  • Thickness of the plate, as a plate that is too thin causes part of the magnetic flux not to be used and to remain wasted in the air.
  • Material of the plate, because higher carbon content lowers holding force, while higher iron content increases it. The best choice is steel with high magnetic permeability and high saturation induction.
  • Surface of the plate, because the more smooth and polished it is, the better the contact and consequently the greater the magnetic saturation.
  • Operating temperature, since all permanent magnets have a negative temperature coefficient. This means that at high temperatures they are weaker, while at sub-zero temperatures they become slightly stronger.

* Lifting capacity was measured using a smooth steel plate of suitable thickness (min. 20 mm), under vertically applied force, however under shearing force the holding force is lower. Additionally, even a slight gap {between} the magnet’s surface and the plate reduces the lifting capacity.

Precautions

Avoid contact with neodymium magnets if you have a nickel 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.

Dust and powder from neodymium magnets are flammable.

Do not attempt to drill into neodymium magnets. Mechanical processing is also not recommended. If the magnet is crushed into fine powder or dust, it becomes highly flammable.

Neodymium magnets can demagnetize at high temperatures.

Despite the fact that magnets have been found to maintain their efficacy up to temperatures of 80°C or 175°F, it's essential to consider that this threshold may fluctuate depending on the magnet's type, configuration, and intended usage.

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 is because many of these devices are equipped with a function that deactivates the device in a magnetic field.

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 have a finger between or on the path of attracting magnets, there may be a severe cut or even a fracture.

 Maintain neodymium magnets far 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.

Neodymium magnets are the most powerful magnets ever created, and their strength can shock you.

Make sure to review all the information we have provided. This will help you avoid harm to your body and damage to the magnets.

Neodymium magnets are extremely fragile, resulting in breaking.

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

Do not place neodymium magnets near a computer HDD, TV, and wallet.

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, or other devices. They can also damage videos, televisions, CRT computer monitors. Do not forget to keep neodymium magnets away from these electronic devices.

Do not bring neodymium magnets close to GPS and smartphones.

Magnetic fields interfere with compasses and magnetometers used in navigation for air and sea transport, as well as internal compasses of smartphones and GPS devices.

Safety rules!

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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e-mail: bok@dhit.pl

tel: +48 888 99 98 98