← previous
next →
Product available Ships today (order by 14:00) CO2 GPSR PPWR REACH

UMS 20x8.6x4.5x7 / N38 - conical magnetic holder

conical magnetic holder

Catalog no 220327

GTIN/EAN: 5906301814177

5.00
Load capacity 6.00 kg / 58.84 N
Diameter Ø
20 mm [±1 mm]
cone dimension Ø
8.6x4.5 mm [±1 mm]
Height
7 mm [±1 mm]
Weight
12 g
Magnetization Direction
↑ axial
Coating
[NiCuNi] Nickel

How we measure these parameters — certificates and measurements

technical specifications »

5.25 zł net / pcs

6.46 zł with VAT (23% VAT) / pcs

price for transport

bulk discounts:

Need more?
Quantity
Net
Gross
price from 1 pcs
5.25 zł
6.46 zł
price from 100 pcs
4.46 zł
5.49 zł
price from 200 pcs
3.41 zł
4.20 zł

Frequently asked questions

How much will a magnetic holder hold in practice?
The catalogue value assumes full contact with smooth steel at least 10 mm thick and a perpendicular pull. Thinner sheet, paint, rust and surface irregularities reduce it considerably: on 1 mm sheet about half remains. Lifting and vertical mounting call for an additional safety margin.
Will a holder work on stainless steel?
Not on austenitic grades 304 and 316 — they are effectively non-magnetic. It will not work on aluminium, copper or brass either. Those materials need a mechanical gripper.
Which coating for which conditions?
Nickel-copper-nickel (NiCuNi) is the standard and covers most applications. Epoxy is used for damp environments and outdoor work, zinc is sufficient for dry interiors. Holders in a steel housing or in rubber also protect the magnet against impact.

Guides from the knowledge base

Want to talk magnets?

Call us now +48 888 99 98 98 alternatively let us know using contact form the contact section.
Specifications and structure of a neodymium magnet can be estimated using our power calculator.

Order by 14:00 and we’ll ship today!

Technical of the product - UMS 20x8.6x4.5x7 / N38 - conical magnetic holder

Specification / characteristics - UMS 20x8.6x4.5x7 / N38 - conical magnetic holder

properties
properties values
Cat. no. 220327
GTIN/EAN 5906301814177
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 20 mm [±1 mm]
cone dimension Ø 8.6x4.5 mm [±1 mm]
Height 7 mm [±1 mm]
Weight 12 g
Magnetization Direction ↑ axial
Load capacity ~ ? 6.00 kg / 58.84 N
Coating [NiCuNi] Nickel
Manufacturing Tolerance ±1 mm

Magnetic properties of material N38

Specification / characteristics UMS 20x8.6x4.5x7 / N38 - conical magnetic holder
properties values units
Remanence Br ? 12.2-12.6 kGs
Remanence Br ? 1220-1260 mT
Coercivity bHc ? 10.8-11.5 kOe
Coercivity bHc ? 860-915 kA/m
Intrinsic coercivity iHc ≥ 12 kOe
Intrinsic coercivity iHc ≥ 955 kA/m
Energy product BHmax ? 36-38 BH max MGOe
Energy product BHmax ? 287-303 BH max KJ/m
Maximum working 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 310 °C
Curie Temperature TF 590 °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
Technical and environmental data

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: 220327-2026
Magnet Unit Converter

Force (pull)

Magnetic Field

Simply populate a single box, to let the tool fill in the rest automatically.

Other offers

NC kulka fi 2 cale / N52 - neocube
Product available Ships today (order by 14:00)

NC kulka fi 2 cale / N52 - neocube

1200.00 zł brutto / pcs
MW 33x10 / N38 - cylindrical magnet
Product available Ships today (order by 14:00)

MW 33x10 / N38 - cylindrical magnet

26.52 zł brutto / pcs
SM 25x200 [2xM8] / N42 - magnetic separator
Product available Ships today (order by 14:00)

SM 25x200 [2xM8] / N42 - magnetic separator

541.20 zł brutto / pcs
SM 28x400 [2xM8] / N52 - magnetic separator
Product available Ships today (order by 14:00)

SM 28x400 [2xM8] / N52 - magnetic separator

1242.30 zł brutto / pcs
Countersunk magnets are indispensable in carpentry, furniture making, and modeling as hidden closures. Thanks to the hole with a chamfer (conical), the screw head hides in the magnet, ensuring a flat contact surface. The steel cup strengthens the magnet force and protects it from cracking upon impact.
Neodymium magnets are sintered ceramics, which means they are very hard but also brittle. It is best to use a screw with a countersunk head perfectly matched to the hole. The screw head should not protrude above the magnet surface, but it cannot burst it either.
For two magnets screwed with cones facing each other (faces) to attract, they must have different polarity. Often a more convenient and cheaper solution is using one magnet and a steel washer (plate) as an armature. Mounting a magnet to a plate eliminates the problem of matching poles and is easier.
This value is the maximum achievement a magnet can obtain on a thick sheet. To increase friction and prevent sliding, it is worth sticking a piece of rubber or anti-slip tape on the magnet. When selecting a magnet for a cabinet, remember that the air gap (e.g., bumpers, seals) weakens the grip.
The steel housing (cup/pot) acts as a magnetic shield, directing all power to the front of the holder. Furthermore, steel protects the brittle neodymium from mechanical damage when closing cabinets (impacts). The countersunk holder is a professional mounting solution with increased durability.

Pros as well as cons of neodymium magnets.

Pros

In addition to their pulling strength, neodymium magnets provide the following advantages:
  • They have constant strength, and over around ten years their performance decreases symbolically – ~1% (in testing),
  • Magnets perfectly resist against loss of magnetization caused by external fields,
  • In other words, due to the reflective finish of silver, the element gains visual value,
  • Magnetic induction on the surface of the magnet is strong,
  • Through (appropriate) combination of ingredients, they can achieve high thermal resistance, enabling operation at temperatures reaching 230°C and above...
  • Possibility of accurate forming and optimizing to atypical needs,
  • Versatile presence in modern industrial fields – they find application in data components, electric drive systems, precision medical tools, also multitasking production systems.
  • Thanks to their power density, small magnets offer high operating force, in miniature format,

Disadvantages

What to avoid - cons of neodymium magnets and proposals for their use:
  • They are fragile upon too strong impacts. To avoid cracks, it is worth securing magnets using a steel holder. Such protection not only shields the magnet but also increases its resistance to damage
  • We warn that neodymium magnets can reduce their power at high temperatures. To prevent this, we suggest our specialized [AH] magnets, which work effectively even at 230°C.
  • Due to the susceptibility of magnets to corrosion in a humid environment, we suggest using waterproof magnets made of rubber, plastic or other material stable to moisture, in case of application outdoors
  • Limited possibility of producing threads in the magnet and complex shapes - preferred is a housing - magnet mounting.
  • Potential hazard resulting from small fragments of magnets can be dangerous, in case of ingestion, which becomes key in the aspect of protecting the youngest. It is also worth noting that small elements of these magnets can disrupt the diagnostic process medical when they are in the body.
  • With budget limitations the cost of neodymium magnets can be a barrier,

Pull force analysis

Best holding force of the magnet in ideal parameters – what it depends on?

The lifting capacity listed is a measurement result executed under the following configuration:
  • using a plate made of high-permeability steel, serving as a ideal flux conductor
  • whose transverse dimension equals approx. 10 mm
  • with a plane perfectly flat
  • under conditions of ideal adhesion (metal-to-metal)
  • during pulling in a direction perpendicular to the mounting surface
  • at conditions approx. 20°C

Determinants of lifting force in real conditions

During everyday use, the actual holding force depends on a number of factors, ranked from the most important:
  • Space between surfaces – every millimeter of distance (caused e.g. by veneer or dirt) drastically reduces the pulling force, often by half at just 0.5 mm.
  • Pull-off angle – remember that the magnet has greatest strength perpendicularly. Under sliding down, the holding force drops significantly, often to levels of 20-30% of the nominal value.
  • Wall thickness – thin material does not allow full use of the magnet. Magnetic flux penetrates through instead of converting into lifting capacity.
  • Plate material – mild steel attracts best. Alloy admixtures lower magnetic permeability and holding force.
  • Smoothness – full contact is obtained only on polished steel. Any scratches and bumps create air cushions, reducing force.
  • Thermal factor – high temperature weakens pulling force. Too high temperature can permanently demagnetize the magnet.

Lifting capacity testing was performed 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 fivefold. Moreover, even a minimal clearance between the magnet and the plate reduces the holding force.

Safety rules for work with NdFeB magnets
Fire warning

Machining of neodymium magnets carries a risk of fire hazard. Neodymium dust reacts violently with oxygen and is difficult to extinguish.

Magnets are brittle

Neodymium magnets are sintered ceramics, which means they are prone to chipping. Collision of two magnets will cause them shattering into shards.

Heat sensitivity

Monitor thermal conditions. Exposing the magnet to high heat will destroy its properties and strength.

Do not give to children

Only for adults. Tiny parts pose a choking risk, leading to serious injuries. Store away from children and animals.

Magnetic media

Do not bring magnets close to a purse, laptop, or screen. The magnetic field can irreversibly ruin these devices and wipe information from cards.

ICD Warning

Warning for patients: Strong magnetic fields affect medical devices. Keep at least 30 cm distance or ask another person to work with the magnets.

Bodily injuries

Watch your fingers. Two large magnets will join immediately with a force of massive weight, crushing anything in their path. Be careful!

Avoid contact if allergic

Medical facts indicate that the nickel plating (the usual finish) is a potent allergen. If your skin reacts to metals, refrain from touching magnets with bare hands or opt for coated magnets.

Magnetic interference

An intense magnetic field negatively affects the functioning of compasses in phones and navigation systems. Maintain magnets close to a device to avoid breaking the sensors.

Caution required

Before starting, check safety instructions. Sudden snapping can destroy the magnet or injure your hand. Be predictive.

Caution! Learn more about hazards in the article: Magnet Safety Guide.