NACHI Bearings

NACHI (Nachi-Fujikoshi) is a full-line Japanese bearing manufacturer that produces standard single-row deep groove ball bearings (6000/6200/6300/6800/6900 series) in its own factories. Its distinguishing feature: according to its official catalog, the contact rubber seal (NSE/2NSE) is BROWN and the non-contact labyrinth rubber seal (NKE/2NKE) is BLUE; this is the easiest way to recognize NACHI in the field. The most common codes on the market are 6205ZZE (two metal shields) and 6205-2NSE9 (two brown contact NBR seals), and the CM clearance code (6205ZZE CM) is widely used in electric motor applications.

Japan

Code structure

Cage, seal and clearance codes are written one after another; the tolerance code is separated by a space. Example: 6205ZZE C3 P6. Because double shield/seal codes begin with 2, they take a hyphen: 6205-2NSE9 C3. In the official catalog the suffixes may also be written without spaces: 6204ZZEC3P6

Suffix	Meaning	Example
ZE	Pressed steel shield on one side (labyrinth gap, non-contact) – current E design	6205ZE
ZZE	Pressed steel shields on both sides – NACHI's current standard shielded type	6205ZZE
Z	Pressed steel shield on one side (basic/older series design)	6205Z
ZZ	Pressed steel shields on both sides (basic/older series design)	6205ZZ
NSE	Contact rubber seal on one side (contacts the inner ring), brown NBR	6205NSE
2NSE	Contact rubber seals on both sides, brown NBR – best dust/water sealing	6205-2NSE
2NSE9	High-performance NBR contact seals on both sides; full designation of the 2NSE type as sold on the market (6205-2NSE9)	6205-2NSE9
NSL	Contact rubber seal on one side (NSL seal design)	6205NSL
2NSL	Contact rubber seals on both sides (NSL seal design)	6205-2NSL
NKE	Non-contact (labyrinth) rubber seal on one side – blue colour, low friction	6205NKE
2NKE	Non-contact (labyrinth) rubber seals on both sides – blue colour, low friction, high speed	6205-2NKE
NK	Non-contact rubber seal on one side (basic series design)	6205NK
2NK	Non-contact rubber seals on both sides (basic series design)	6205-2NK
N	Snap ring groove in the outer ring, no snap ring	6205N
NR	Snap ring groove in the outer ring + fitted snap ring (marked only as 'N' on the bearing)	6205NR
G	Non-metallic (polyamide/plastic) cage; indicated by the G suffix on the packaging	6205G

Markings on the bearing: Laser marking on the outer ring side face: the "NACHI" brand name on the top line (the NACHI logo on some batches), the full bearing code below or beside it (e.g. 6205ZZE, 6205-2NSE9 C3) and the country of origin "JAPAN". On sealed types, the same brand and code information is repeated, embossed/printed, on the metal reinforcement of the brown seal. Catalog note: on bearings with the NR suffix, the ring is marked without the R, as "N" only; duplex, sleeve and grease codes (*) are never marked on the bearing. Normal clearance (CN) and normal precision (JIS 0) codes are not marked either.