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sales@tujinmagnet.com
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+86-18858010843
Convex Cylinder NdFeB Magnets with Hole is a high-performance, high-strength permanent magnet material product. It is made of advanced NdFeB magnetic material, with good magnetic properties, high energy density and good corrosion resistance. The uniqueness of this magnet lies in its convex cylindrical appearance design and the through-hole design in the middle, which enables it to play an excellent role in various application scenarios.
Appearance description:
Convex Cylinder NdFeB Magnets with Hole is in the shape of a convex cylinder, that is, the upper part is a larger ring-shaped protrusion, and the lower part is a smaller cylinder. This design is not only beautiful and generous, but also increases the strength and stability of the magnet. In terms of size, it can be customized according to customer needs to meet the needs of different application scenarios. The color of the magnet is silver or gray, showing a metallic texture. The surface looks smooth and shiny, thanks to its fine manufacturing process and high-quality material selection. There is a hole in the middle of the bottom of the magnet. This design allows the magnet to be fixed and installed by bolts, screws or other connectors. The size and position of the hole can be customized according to customer needs to meet specific installation needs.
Application scenarios
Mechanical parts: used to manufacture magnetic components in various mechanical parts, such as sensors, actuators, etc. Through the convex cylindrical appearance design and the design of the middle through hole, it can be easily connected and fixed with other mechanical parts.
Electronic equipment: used to manufacture magnetic components in electronic equipment, such as speakers, microphones, etc. The convex cylindrical appearance design and strong magnetic force enable magnets to play an excellent role in these devices.
Automobile manufacturing: used to manufacture magnetic components in automotive parts, such as door locks, window lifters, etc. Through the design of the middle through hole, it can be easily installed in automotive parts and connected with other components.
Other fields: It can also be used for magnetic components in renewable energy equipment such as wind power generation and hydropower generation, as well as magnetic components in daily life such as toys, stationery, and crafts.
Products show

Surface Coating & Corrosoin Resistance
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| Nickel(Ni-Cu-Ni) | Zinc(Zn) | Black Epoxy | Gold |
| Type | Color | Plating Thickness | Working Temperature |
Advantage & Suitable | Salt Spray Resistance | |||||
| Nickel(NiCuNi) | silver | 20-30 um | ≤200 | high oxidation resistance, good glossiness, stable performance, long service life | > 72 hrs | |||||
| Zinc (Zn) | blue white | 10-20 um | ≤160 | suitable for low requirements for surface appearance & oxidation resistance | > 48 hrs | |||||
| Epoxy | black | 10-30 um | ≤120 | suitable for high anti-corrosion and strict atmospheric environment | > 96 hrs | |||||
| Gold | Gold | 5-30 um | ≤200 | suitable for decoration accessories, gift box etc. | > 24 hrs | |||||
Tolerance

| Standard Product | D.OD | ID | L | W | H |
| <5mm | ±0.1mm | ±0.1mm | ±0.1mm | ±0.1mm | ±0.1mm |
| <10mm | ±0.1mm | ±0.1mm | ±0.1mm | ±0.1mm | ±0.1mm |
| <20mm | ±0.1mm | ±0.1mm | ±0.1mm | ±0.1mm | ±0.1mm |
| <50mm | ±0.1mm | ±0.1mm | ±0.1mm | ±0.1mm | ±0.1mm |
| <100mm | ±0.15mm | ±0.15mm | ±0.15mm | ±0.15mm | ±0.15mm |
| >100mm | ±0.2mm | ±0.2mm | ±0.2mm | ±0.2mm | ±0.2mm |
Magnetization Direction
| Disc&Cylinder-through Thickness | Disc&Cylinder-through Diameter | Spheres- through Diameter |
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Poles on the flat surfaces
|
Poles on the side surfaces |
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| Block- through Thickness | Block- through Length | Arc- through Diamter |
|
Poles on the larger flat surfaces |
Poles on the smaller flat surfaces |
Poles on outside&inside faces |
| Arc- through Length | Ring- through Surfaces | Ring- through Surfaces |
|
Poles on outside&inside faces |
Planar octupole magnetization |
Planar quadrupole magnetization |
Sintered NdFeB Magnetic Properties
| Grade | Remanence | Coercive Force | Intrinsic Coercivity | Maximum Energy | Working≤ | |||||||
| Br(KG) | Br(T) | Hcb (KOe) |
Hcb (KA/m) |
Hcj (KOe) |
Hcj (KA/m) |
(BH)max(MGOe) | (BH)max (KJ/ m) |
℃ | ||||
| Max | Min | Max | Min | |||||||||
| N35 | ≥11.8 | ≥1.18 | ≥10.8 | ≥860 | ≥12 | ≥960 | 37 | 33 | 295 | 263 | N | ≤80 |
| N38 | ≥12.3 | ≥1.23 | ≥10.8 | ≥860 | ≥12 | ≥960 | 39 | 36 | 310 | 287 | ||
| N40 | ≥12.7 | ≥1.27 | ≥11.0 | ≥876 | ≥12 | ≥960 | 41 | 38 | 327 | 302 | ||
| N42 | ≥13.0 | ≥1.30 | ≥11.0 | ≥876 | ≥12 | ≥960 | 43 | 40 | 343 | 320 | ||
| N45 | ≥13.3 | ≥1.33 | ≥11.0 | ≥876 | ≥12 | ≥960 | 46 | 42 | 366 | 335 | ||
| N48 | ≥13.7 | ≥1.37 | ≥10.5 | ≥836 | ≥12 | ≥960 | 49 | 45 | 390 | 358 | ||
| N50 | ≥14.0 | ≥1.40 | ≥10.5 | ≥836 | ≥12 | ≥960 | 51 | 47 | 406 | 374 | ||
| N52 | ≥14.2 | ≥1.42 | ≥10.5 | ≥836 | ≥12 | ≥960 | 53 | 49 | 422 | 390 | ||
| N54 | ≥14.4 | ≥1.44 | ≥10.5 | ≥836 | ≥11 | ≥876 | 55 | 51 | 438 | 406 | ||
| N35M | ≥11.8 | ≥1.18 | ≥10.8 | ≥860 | ≥14 | ≥1114 | 37 | 33 | 295 | 263 | M | ≤100 |
| N38M | ≥12.3 | ≥1.23 | ≥11.0 | ≥876 | ≥14 | ≥1114 | 39 | 36 | 310 | 287 | ||
| N40M | ≥12.7 | ≥1.27 | ≥11.5 | ≥915 | ≥14 | ≥1114 | 41 | 38 | 327 | 302 | ||
| N42M | ≥13.0 | ≥1.30 | ≥11.8 | ≥939 | ≥14 | ≥1114 | 43 | 40 | 343 | 320 | ||
| N45M | ≥13.3 | ≥1.33 | ≥12.0 | ≥956 | ≥14 | ≥1114 | 46 | 42 | 366 | 335 | ||
| N48M | ≥13.7 | ≥1.37 | ≥12.2 | ≥972 | ≥14 | ≥1114 | 49 | 45 | 390 | 358 | ||
| N50M | ≥14.0 | ≥1.40 | ≥12.5 | ≥995 | ≥14 | ≥1114 | 51 | 47 | 406 | 374 | ||
| N52M | ≥14.2 | ≥1.42 | ≥12.5 | ≥995 | ≥14 | ≥1114 | 53 | 49 | 422 | 390 | ||
| N33H | ≥11.4 | ≥1.14 | ≥10.6 | ≥844 | ≥17 | ≥1350 | 35 | 31 | 279 | 247 | H | ≤120 |
| N35H | ≥11.8 | ≥1.18 | ≥10.8 | ≥860 | ≥17 | ≥1350 | 37 | 33 | 295 | 263 | ||
| N38H | ≥12.3 | ≥1.23 | ≥11.0 | ≥876 | ≥17 | ≥1350 | 39 | 36 | 310 | 287 | ||
| N40H | ≥12.7 | ≥1.27 | ≥11.5 | ≥916 | ≥17 | ≥1350 | 41 | 38 | 327 | 302 | ||
| N42H | ≥13.0 | ≥1.30 | ≥11.8 | ≥940 | ≥17 | ≥1350 | 43 | 40 | 343 | 320 | ||
| N45H | ≥13.3 | ≥1.33 | ≥12.0 | ≥955 | ≥17 | ≥1350 | 46 | 42 | 366 | 335 | ||
| N48H | ≥13.6 | ≥1.36 | ≥12.2 | ≥971 | ≥17 | ≥1350 | 49 | 45 | 390 | 358 | ||
| N50H | ≥14 | ≥1.4 | ≥12.5 | ≥995 | ≥17 | ≥1350 | 51 | 47 | 406 | 374 | ||
| N52H | ≥14.3 | ≥1.43 | ≥12.5 | ≥995 | ≥17 | ≥1350 | 53 | 49 | 422 | 390 | ||
| N33SH | ≥11.4 | ≥1.14 | ≥10.6 | ≥844 | ≥20 | ≥1592 | 35 | 31 | 279 | 247 | SH | ≤150 |
| N35SH | ≥11.8 | ≥1.18 | ≥10.8 | ≥860 | ≥20 | ≥1592 | 37 | 33 | 295 | 263 | ||
| N38SH | ≥12.3 | ≥1.23 | ≥11.0 | ≥876 | ≥20 | ≥1592 | 39 | 36 | 310 | 287 | ||
| N40SH | ≥12.6 | ≥1.26 | ≥11.5 | ≥916 | ≥20 | ≥1592 | 41 | 38 | 327 | 302 | ||
| N42SH | ≥12.9 | ≥1.29 | ≥11.8 | ≥940 | ≥20 | ≥1592 | 43 | 40 | 343 | 320 | ||
| N45SH | ≥13.2 | ≥1.32 | ≥12.0 | ≥955 | ≥20 | ≥1592 | 46 | 42 | 366 | 335 | ||
| N48SH | ≥13.6 | ≥1.36 | ≥12.2 | ≥971 | ≥20 | ≥1592 | 49 | 45 | 390 | 358 | ||
| N50SH | ≥14 | ≥1.4 | ≥12.5 | ≥995 | ≥20 | ≥1592 | 51 | 47 | 406 | 374 | ||
| N33UH | ≥11.4 | ≥1.14 | ≥10.6 | ≥844 | ≥25 | ≥1990 | 35 | 31 | 279 | 247 | UH | ≤180 |
| N35UH | ≥11.8 | ≥1.18 | ≥10.8 | ≥860 | ≥25 | ≥1990 | 37 | 33 | 295 | 263 | ||
| N38UH | ≥12.3 | ≥1.23 | ≥11.0 | ≥876 | ≥25 | ≥1990 | 39 | 36 | 310 | 287 | ||
| N40UH | ≥12.6 | ≥1.26 | ≥11.5 | ≥916 | ≥25 | ≥1990 | 41 | 38 | 327 | 302 | ||
| N42UH | ≥12.9 | ≥1.29 | ≥11.8 | ≥940 | ≥25 | ≥1990 | 43 | 40 | 343 | 320 | ||
| N45UH | ≥13.2 | ≥1.32 | ≥12.0 | ≥955 | ≥25 | ≥1990 | 46 | 42 | 366 | 335 | ||
| N48UH | ≥13.6 | ≥1.36 | ≥12.2 | ≥971 | ≥25 | ≥1990 | 49 | 45 | 390 | 358 | ||
| N28EH | ≥10.4 | ≥1.04 | ≥9.50 | ≥756 | ≥30 | ≥2388 | 30 | 26 | 239 | 207 | EH | ≤200 |
| N30EH | ≥10.8 | ≥1.08 | ≥9.50 | ≥756 | ≥30 | ≥2388 | 32 | 28 | 255 | 223 | ||
| N33EH | ≥11.4 | ≥1.14 | ≥10.6 | ≥844 | ≥30 | ≥2388 | 35 | 31 | 279 | 247 | ||
| N35EH | ≥11.8 | ≥1.18 | ≥10.8 | ≥860 | ≥30 | ≥2388 | 37 | 33 | 295 | 263 | ||
| N38EH | ≥12.3 | ≥1.23 | ≥11.0 | ≥876 | ≥30 | ≥2388 | 39 | 36 | 310 | 287 | ||
| N40EH | ≥12.6 | ≥1.26 | ≥11.5 | ≥916 | ≥30 | ≥2388 | 41 | 38 | 327 | 302 | ||
| N42EH | ≥12.9 | ≥1.29 | ≥11.8 | ≥940 | ≥30 | ≥2388 | 43 | 41 | 343 | 320 | ||
| N45EH | ≥13.2 | ≥1.32 | ≥12.0 | ≥955 | ≥30 | ≥2388 | 46 | 42 | 366 | 335 | ||
| N30TH | ≥10.8 | ≥1.08 | ≥9.50 | ≥756 | ≥35 | ≥2786 | 32 | 28 | 255 | 223 | TH | ≤220 |
| N33TH | ≥11.4 | ≥1.14 | ≥10.6 | ≥844 | ≥35 | ≥2786 | 35 | 31 | 279 | 247 | ||
| N35TH | ≥11.8 | ≥1.18 | ≥11.0 | ≥876 | ≥35 | ≥2786 | 37 | 33 | 295 | 263 | ||
| N38TH | ≥12.2 | ≥1.22 | ≥11.0 | ≥876 | ≥33 | ≥2627 | 39 | 36 | 310 | 287 | ||
| Remarks: The maximum working temperature depends on the shape, size, and coating of the magnet, the highest working temperature in the table is the test data for standard sample. | ||||||||||||
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