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SM 25x225 [2xM8] / N42 - magnetic roller

magnetic separator

catalog number 130292

GTIN: 5906301812852

no reviews

diameter Ø

25 mm [±0,1 mm]

height

225 mm [±0,1 mm]

max. temperature

≤ 80 °C

615.00 ZŁ gross price (including VAT) / pcs +

500.00 ZŁ net price + 23% VAT / pcs

bulk discounts:

need more quantity?
price from 1 pcs
500.00 ZŁ
615.00 ZŁ
price from 5 pcs
475.00 ZŁ
584.25 ZŁ
price from 9 pcs
450.00 ZŁ
553.50 ZŁ

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Call us tel: +48 888 99 98 98 or contact us via contact form on our website. You can check the strength and the appearance of neodymium magnet in our magnetic calculator power calculator

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

Specification: magnetic separator 25x225 [2xM8] / N42

Characteristics: magnetic separator 25x225 [2xM8] / N42
Properties
Values
catalog number
130292
GTIN
5906301812852
production / distribution
Dhit sp. z o.o.
country of origin
Poland / China / Germany
customs code
85059029
diameter Ø
25 mm [±0,1 mm]
height
225 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 - 8 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 embedded in a construction made of stainless steel usually AISI304. As a result, it is possible to precisely remove ferromagnetic elements from other materials. A key aspect of its operation is the repulsion of N and S poles of neodymium magnets, which causes magnetic substances to be targeted. 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 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 effectively segregate them.
Yes, magnetic rollers are employed in the food sector to clear metallic contaminants, for example iron fragments or iron dust. Our rollers are made from acid-resistant steel, EN 1.4301, intended for contact with food.
Magnetic rollers, otherwise cylindrical magnets, are used in metal separation, food production as well as waste processing. They help in eliminating iron dust during the process of separating metals from other wastes.
Our magnetic rollers are built with a neodymium magnet placed in a stainless steel tube cylinder made of stainless steel with a wall thickness of 1mm.
Both ends of the magnetic bar can be with M8 threaded openings, allowing for quick installation in machines or magnetic filter drawers. A "blind" version is also possible in manual separators.
In terms of magnetic properties, magnetic bars stand out in terms of magnetic force lines, flux density and the area of operation of the magnetic field. We produce them in materials, N42 and N52.
Often it is believed that the greater the magnet's power, the more effective. Nevertheless, the effectiveness 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 expected needs. The standard operating temperature of a magnetic bar is 80°C.
In the case where the magnet is thin, the magnetic force lines will be more compressed. By contrast, in the case of a thicker magnet, the force lines will be extended and reach further.
For creating the casings of magnetic separators - rollers, usually stainless steel is used, especially types AISI 304, AISI 316, and AISI 316L.
In a saltwater environment, AISI 316 steel exhibits the best resistance thanks to its outstanding anti-corrosion properties.
Magnetic bars 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 complex filtration systems.
Technical designations and terms pertaining to magnetic separators include among others polarity, magnetic induction, magnet pitch, 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 close to the magnetic pole. The outcome is verified in a value table - the lowest is N30. All designations below N27 or N25 indicate recycling that falls below the standard - they are not suitable.
Neodymium magnetic bars offer many advantages, including excellent separation efficiency, strong magnetic field, and durability. On the other hand, among the drawbacks, one can mention the requirement for frequent cleaning, greater weight, and potential installation difficulties.
To properly maintain of neodymium magnetic rollers, it is advised to clean them regularly from deposits, avoid extreme temperatures up to 80°C, and protect them from moisture if the threads are not sealed - in our case. The rollers our rollers have an IP67 waterproof rating, so if they are not sealed, the magnets inside may rust and weaken. Roller inspections are advised to be conducted every two years. Care should be taken as there is a possibility of finger injury. If the protective tube is only 0.5 mm thick, it can be worn down, 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 and disadvantages of neodymium magnets NdFeB.

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

  • They do not lose their strength (of the magnet). After about 10 years, their strength decreases by only ~1% (theoretically),
  • They protect against demagnetization caused by external magnetic sources very well,
  • In other words, thanks to the shiny coating of nickel, gold, or silver, the element acquires an aesthetic appearance,
  • They have exceptionally 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...
  • The ability for precise shaping or customization to specific needs – neodymium magnets can be produced in many variants of shapes and sizes, which enhances their versatility in applications.
  • Wide application in advanced technologically fields – are utilized in computer drives, electric motors, medical devices or very advanced devices.

Disadvantages of neodymium magnets:

  • They are prone to breaking as they are fragile when subjected to a powerful impact. If the magnets are exposed to impacts, we recommend 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,
  • Magnets lose their strength 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
  • Health risk to health from tiny fragments of magnets can be dangerous, in case of ingestion, which becomes significant in the aspect of protecting young children. Additionally, small elements of these magnets have the potential to hinder the diagnostic process in case of swallowing.

Handle with Care: Neodymium Magnets

Neodymium magnets are not recommended for 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.

Under no circumstances should neodymium magnets be placed near a computer HDD, TV, and wallet.

Neodymium magnets generate strong magnetic fields that can damage magnetic media such as floppy disks, video tapes, HDDs, credit cards, magnetic ID cards, cassette tapes, etc. devices. They can also destroy videos, televisions, CRT computer monitors. Remember not to place neodymium magnets close to these electronic devices.

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.

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.

Magnets will crack or crumble with uncontrolled connecting to each other. You can't move them to each other. At a distance less than 10 cm you should hold them very strongly.

Neodymium magnetic are fragile and can easily break and shatter.

Magnets made of neodymium are delicate and 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. In the case of a collision between two magnets, there can be a scattering of small sharp metal fragments in different directions. Protecting your eyes is essential.

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.

Dust and powder from neodymium magnets are highly 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 are the strongest, most remarkable magnets on the planet, and the surprising force between them can shock you at first.

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

Never bring neodymium magnets close to a phone and GPS.

Magnetic fields can interfere with compasses and magnetometers used in aviation and maritime navigation, as well as internal compasses of smartphones and GPS devices. There are neodymium magnets in every smartphone, for example, in the microphone and speakers.

  Do not give neodymium magnets to children.

Not all neodymium magnets are toys, so do not let children play with them. In the case of small magnets, they can be swallowed and cause choking. In such cases, the only solution is to undergo surgery to remove the magnets, and otherwise, it can even lead to death.

To raise awareness of why neodymium magnets are so dangerous, see the article titled How dangerous are strong neodymium magnets?.
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e-mail: bok@dhit.pl

tel: +48 888 99 98 98