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SM 25x300 [2xM8] / N42 - magnetic separator

magnetic separator

Catalog no 130295

GTIN: 5906301812883

5

Diameter Ø [±0,1 mm]

25 mm

Height [±0,1 mm]

300 mm

Weight

0.01 g

836.40 with VAT / pcs + price for transport

680.00 ZŁ net + 23% VAT / pcs

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SM 25x300 [2xM8] / N42 - magnetic separator

Specification/characteristics SM 25x300 [2xM8] / N42 - magnetic separator
properties
values
Cat. no.
130295
GTIN
5906301812883
Production/Distribution
Dhit sp. z o.o.
Country of origin
Poland / China / Germany
Customs code
85059029
Diameter Ø
25 mm [±0,1 mm]
Height
300 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 main mechanism of the magnetic separator is the use of neodymium magnets, placed in a casing made of stainless steel mostly AISI304. Due to this, it is possible to precisely segregate ferromagnetic elements 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 magnet and its structure's pitch determine the power and range of the separator's operation.
Generally speaking, magnetic separators are used to segregate ferromagnetic elements. 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 separator will not effectively segregate them.
Yes, magnetic rollers are employed in the food industry to clear metallic contaminants, for example iron fragments or iron dust. Our rods are made from durable acid-resistant steel, EN 1.4301, suitable for use in food.
Magnetic rollers, often called cylindrical magnets, are employed in food production, metal separation as well as waste processing. They help in removing iron dust during the process of separating metals from other wastes.
Our magnetic rollers are composed of neodymium magnets anchored in a tube of stainless steel with a wall thickness of 1mm.
Both ends of the magnetic bar will be with M8 threaded openings, which enables simple mounting 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 two materials, N42 as well as N52.
Often it is believed that the greater the magnet's power, the more effective. Nevertheless, the effectiveness 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 short. By contrast, in the case of a thicker magnet, the force lines are longer and reach further.
For making the casings of magnetic separators - rollers, most often stainless steel is utilized, especially types AISI 316, AISI 316L, and AISI 304.
In a saltwater contact, AISI 316 steel exhibits the best resistance due to its outstanding corrosion resistance.
Magnetic bars are characterized by their specific arrangement of poles and their ability to attract magnetic substances directly onto their surface, as opposed to other separators that may utilize complex filtration systems.
Technical designations and terms related to magnetic separators include amongst others polarity, magnetic induction, magnet pitch, as well as the steel type applied.
Magnetic induction for a roller is measured 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 outcome is verified 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 a very strong magnetic field, the ability to capture even the tiniest metal particles, and durability. However, some of the downsides may involve the need for regular cleaning, higher cost, and potential installation challenges.
By ensuring proper maintenance of neodymium magnetic rollers, you should regularly cleaning them from contaminants, avoiding high temperatures up to 80°C, and protecting them from moisture if the threads are not sealed – in ours, they are. The rollers our rollers have waterproofing IP67, so if they are not sealed, the magnets inside can oxidize and lose their power. Magnetic field measurements should be carried out every two years. Care should be taken, as there is a risk getting pinched. 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 is equal 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 the removal of iron metals and iron filings is essential.

Advantages and disadvantages of neodymium magnets NdFeB.

In addition to their remarkable strength, neodymium magnets offer the following advantages:

  • Their power is maintained, and after approximately ten years, it drops only by ~1% (theoretically),
  • They show exceptional resistance to demagnetization from external field exposure,
  • Thanks to the polished finish and gold coating, they have an elegant appearance,
  • The outer field strength of the magnet shows elevated magnetic properties,
  • Thanks to their high temperature resistance, they can operate (depending on the form) even at temperatures up to 230°C or more,
  • Thanks to the freedom in shaping and the capability to adapt to specific requirements, neodymium magnets can be created in diverse shapes and sizes, which expands their usage potential,
  • Wide application in advanced technical fields – they find application in hard drives, electric drives, healthcare devices or even sophisticated instruments,
  • Compactness – despite their small size, they deliver powerful magnetism, making them ideal for precision applications

Disadvantages of rare earth magnets:

  • They can break when subjected to a heavy 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 , and at the same time increases its overall robustness,
  • High temperatures may significantly reduce the strength of neodymium magnets. Typically, above 80°C, they experience permanent loss in performance (depending on size). To prevent this, we offer heat-resistant magnets marked [AH], capable of working up to 230°C, which makes them perfect for high-temperature use,
  • Magnets exposed to wet conditions can oxidize. Therefore, for outdoor applications, we advise waterproof types made of coated materials,
  • Limited ability to create complex details in the magnet – the use of a external casing is recommended,
  • Possible threat linked to microscopic shards may arise, especially if swallowed, which is significant in the family environments. Furthermore, tiny components from these products can hinder health screening if inside the body,
  • Higher purchase price is an important factor to consider compared to ceramic magnets, especially in budget-sensitive applications

Best holding force of the magnet in ideal parameterswhat contributes to it?

The given strength of the magnet means the optimal strength, measured in the best circumstances, that is:

  • using a steel plate with low carbon content, acting as a magnetic circuit closure
  • with a thickness of minimum 10 mm
  • with a smooth surface
  • in conditions of no clearance
  • under perpendicular detachment force
  • at room temperature

Practical lifting capacity: influencing factors

The lifting capacity of a magnet depends on in practice the following factors, ordered from most important to least significant:

  • Air gap between the magnet and the plate, since 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.

* Holding force was measured on the plate surface of 20 mm thickness, when a perpendicular force was applied, whereas under attempts to slide the magnet the lifting capacity is smaller. Moreover, even a small distance {between} the magnet and the plate lowers the load capacity.

Handle Neodymium Magnets Carefully

Comparing neodymium magnets to ferrite magnets (found in speakers), they are 10 times more powerful, and their power can surprise 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.

Magnets will attract to each other, so remember not to allow them to pinch together without control or place your fingers in their path.

Magnets attract each other within a distance of several to around 10 cm from each other. Don't put your fingers in the path of magnet attraction, as a major injury may occur. Magnets, depending on their size, can even cut off a finger or there can be a serious pressure or even a fracture.

Neodymium magnets are not recommended for people with pacemakers.

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.

Avoid bringing neodymium magnets close to a phone or GPS.

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.

Neodymium magnets can become demagnetized at high temperatures.

Although magnets are generally resilient, their ability to maintain their magnetic potency can be influenced by factors like the type of material used, the magnet's shape, and the intended purpose for which it is employed.

  Magnets are not toys, children should not play with them.

Neodymium magnets are not toys. Be cautious and make sure no child plays 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 severe injuries, and even death.

Dust and powder from neodymium magnets are flammable.

Avoid drilling or mechanical processing of neodymium magnets. Once crushed into fine powder or dust, this material becomes highly flammable.

The magnet is coated with nickel - be careful 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, try wearing gloves or avoid direct contact with nickel-plated neodymium magnets.

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

Strong magnetic fields emitted by neodymium magnets can destroy magnetic storage media such as floppy disks, credit cards, magnetic ID cards, cassette tapes, video tapes, or other devices. They can also damage televisions, VCRs, computer monitors, and CRT displays. Avoid placing neodymium magnets in close proximity to electronic devices.

Neodymium magnets are fragile as well as can easily crack and get damaged.

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

Be careful!

To illustrate why neodymium magnets are so dangerous, see the article - How dangerous are strong neodymium magnets?.

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e-mail: bok@dhit.pl

tel: +48 888 99 98 98