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SM 25x350 [2xM8] / N42 - magnetic separator

magnetic separator

Catalog no 130350

GTIN/EAN: 5906301812982

Diameter Ø

25 mm [±1 mm]

Height

350 mm [±1 mm]

Weight

1360 g

Magnetic Flux

~ 6 500 Gauss [±5%]

984.00 with VAT / pcs + price for transport

800.00 ZŁ net + 23% VAT / pcs

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Technical specification of the product - SM 25x350 [2xM8] / N42 - magnetic separator

Specification / characteristics - SM 25x350 [2xM8] / N42 - magnetic separator

properties
properties values
Cat. no. 130350
GTIN/EAN 5906301812982
Production/Distribution Dhit sp. z o.o.
ul. Zielona 14 05-850 Ożarów Mazowiecki PL
Country of origin Poland / China / Germany
Customs code 85059029
Diameter Ø 25 mm [±1 mm]
Height 350 mm [±1 mm]
Weight 1360 g
Material Type Stainless steel AISI 304 / A2
Magnetic Flux ~ 6 500 Gauss [±5%]
Size/Mount Quantity 2xM8
Polarity circumferential - 13 poles
Casing Tube Thickness 1 mm
Manufacturing Tolerance ±1 mm

Magnetic properties of material N42

Specification / characteristics SM 25x350 [2xM8] / N42 - magnetic separator
properties values units
remenance Br [min. - max.] ? 12.9-13.2 kGs
remenance Br [min. - max.] ? 1290-1320 mT
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 at 20°C

Physical properties of sintered neodymium magnets Nd2Fe14B at 20°C
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 10-6 °C-1
Thermal expansion perpendicular (⊥) to orientation (M) -(1-3) x 10-6 °C-1
Young's modulus 1.7 x 104 kg/mm²

Table 1: Rod construction
SM 25x350 [2xM8] / N42

Parameter Value Description / Unit
Diameter (Ø) 25 mm
Total length 350 mm (L)
Active length 314 mm
Section count 13 modules
Dead zone 36 mm (2x 18mm starter)
Weight (est.) ~1306 g
Active area 247 cm² (Area)
Housing material AISI 304 1.4301 (Inox)
Surface finish Ra < 0.8 µm Polished
Temp. class 80°C Standard (N)
Force loss (at max °C) -12.8% Reversible loss (physics)
Force (calculated) 10.6 kg (theor.)
Induction (surface) ~6 500 Gauss (Max)

Chart 2: Field profile (13 sections)

Chart 3: Temperature performance

Technical specification and ecology
Material specification
iron (Fe) 64% – 68%
neodymium (Nd) 29% – 32%
boron (B) 1.1% – 1.2%
dysprosium (Dy) 0.5% – 2.0%
coating (Ni-Cu-Ni) < 0.05%
Environmental data
recyclability (EoL) 100%
recycled raw materials ~10% (pre-cons)
carbon footprint low / zredukowany
waste code (EWC) 16 02 16
Safety card (GPSR)
responsible entity
Dhit sp. z o.o.
ul. Kościuszki 6A, 05-850 Ożarów Mazowiecki
tel: +48 22 499 98 98 | e-mail: bok@dhit.pl
batch number/type
id: 130350-2026
Measurement Calculator
Magnet pull force

Field Strength

Other products

This product serves to effectively catch ferromagnetic contaminants from bulk and liquid products. Its task is separation (separation) of metal filings from the transported material. Thanks to the use of strong neodymium magnets, the rod catches even metallic dust.
The construction relies on a sealed, welded stainless steel housing, polished smooth. Inside there is a stack of strong neodymium magnets arranged in a special configuration (magnetic circuit). Such construction ensures full resistance to corrosion, water, oils, and acids.
Due to the high power of the magnet, direct removal of filings can be troublesome and time-consuming. You can use compressed air or special non-magnetic strippers (rings). For easier operation, it is worth considering ordering a rod in a version with a cleaning sleeve.
Magnetic induction measured in Gauss (Gs) determines the density of magnetic flux on the rod surface. For basic machine protection against pieces of iron, standard power is sufficient. For the food and precision industry, we recommend the highest induction parameters.
Yes, as a manufacturer, we make rods of any length and diameter (standard is dia 25mm and 32mm). You can choose a mounting method consistent with your technical design. Contact us for a quote on a non-standard dimension.

Strengths and weaknesses of rare earth magnets.

Advantages

Besides their high retention, neodymium magnets are valued for these benefits:
  • They have constant strength, and over nearly 10 years their performance decreases symbolically – ~1% (according to theory),
  • They maintain their magnetic properties even under close interference source,
  • By covering with a reflective coating of gold, the element acquires an modern look,
  • Magnetic induction on the working part of the magnet turns out to be maximum,
  • Made from properly selected components, these magnets show impressive resistance to high heat, enabling them to function (depending on their form) at temperatures up to 230°C and above...
  • Possibility of exact creating as well as adjusting to precise conditions,
  • Huge importance in advanced technology sectors – they are commonly used in mass storage devices, electric drive systems, advanced medical instruments, and multitasking production systems.
  • Relatively small size with high pulling force – neodymium magnets offer impressive pulling force in tiny dimensions, which enables their usage in compact constructions

Weaknesses

Disadvantages of neodymium magnets:
  • They are fragile upon heavy impacts. To avoid cracks, it is worth protecting magnets in special housings. Such protection not only shields the magnet but also improves its resistance to damage
  • Neodymium magnets decrease their power under the influence of heating. As soon as 80°C is exceeded, many of them start losing their power. Therefore, we recommend our special magnets marked [AH], which maintain durability even at temperatures up to 230°C
  • Due to the susceptibility of magnets to corrosion in a humid environment, we advise using waterproof magnets made of rubber, plastic or other material resistant to moisture, when using outdoors
  • Due to limitations in producing threads and complex shapes in magnets, we propose using cover - magnetic holder.
  • Possible danger resulting from small fragments of magnets pose a threat, when accidentally swallowed, which becomes key in the aspect of protecting the youngest. It is also worth noting that small elements of these devices can disrupt the diagnostic process medical when they are in the body.
  • Due to complex production process, their price is higher than average,

Holding force characteristics

Magnetic strength at its maximum – what affects it?

The lifting capacity listed is a result of laboratory testing conducted under standard conditions:
  • on a plate made of structural steel, effectively closing the magnetic field
  • whose transverse dimension is min. 10 mm
  • with an ideally smooth touching surface
  • with direct contact (without coatings)
  • for force applied at a right angle (in the magnet axis)
  • in stable room temperature

Determinants of practical lifting force of a magnet

Bear in mind that the working load will differ influenced by the following factors, starting with the most relevant:
  • Clearance – existence of foreign body (rust, dirt, gap) acts as an insulator, which lowers power rapidly (even by 50% at 0.5 mm).
  • Direction of force – maximum parameter is reached only during pulling at a 90° angle. The resistance to sliding of the magnet along the plate is typically several times smaller (approx. 1/5 of the lifting capacity).
  • Steel thickness – too thin steel causes magnetic saturation, causing part of the flux to be wasted to the other side.
  • Material type – ideal substrate is pure iron steel. Cast iron may generate lower lifting capacity.
  • Smoothness – full contact is possible only on polished steel. Rough texture create air cushions, reducing force.
  • Heat – NdFeB sinters have a negative temperature coefficient. At higher temperatures they lose power, and at low temperatures they can be stronger (up to a certain limit).

Lifting capacity testing was carried out on plates with a smooth surface of suitable thickness, under perpendicular forces, however under attempts to slide the magnet the load capacity is reduced by as much as 5 times. In addition, even a small distance between the magnet’s surface and the plate reduces the holding force.

Precautions when working with neodymium magnets
Safe operation

Before use, read the rules. Sudden snapping can destroy the magnet or injure your hand. Think ahead.

Power loss in heat

Control the heat. Exposing the magnet above 80 degrees Celsius will ruin its properties and strength.

ICD Warning

People with a heart stimulator have to maintain an safe separation from magnets. The magnetism can stop the functioning of the implant.

Electronic devices

Avoid bringing magnets close to a purse, laptop, or TV. The magnetic field can destroy these devices and erase data from cards.

Risk of cracking

Watch out for shards. Magnets can fracture upon violent connection, launching sharp fragments into the air. Wear goggles.

Phone sensors

Note: neodymium magnets produce a field that disrupts sensitive sensors. Keep a separation from your mobile, tablet, and navigation systems.

Adults only

Neodymium magnets are not suitable for play. Swallowing a few magnets may result in them attracting across intestines, which constitutes a critical condition and necessitates urgent medical intervention.

Nickel coating and allergies

Allergy Notice: The Ni-Cu-Ni coating contains nickel. If skin irritation happens, cease handling magnets and wear gloves.

Crushing risk

Large magnets can break fingers instantly. Under no circumstances put your hand between two attracting surfaces.

Fire risk

Fire hazard: Rare earth powder is explosive. Do not process magnets without safety gear as this risks ignition.

Warning! Details about hazards in the article: Magnet Safety Guide.
Dhit sp. z o.o.

e-mail: bok@dhit.pl

tel: +48 888 99 98 98