The nomenclature of NTN bearing numbers indicate bearing type, dimensions, tolerances, internal construction, and other related specifications. NTN bearing numbers are compreised of a "basic number" followed by "supplementary codes."
The nomenclature of NTN basic number indicates general information about a bearing, such as its fundamental type, boundary dimensions, series number, bore diameter code and contact angle. The supplementary codes derive from prefixes and suffixes which indicate a bearing's tolerances, internal clearances, and related specifications.
NTN bearing number examples
NTN Angular contact ball bearing
NTN Cylindrical roller bearings
NTN Tapered roller bearings
NTN Spherical roller bearings
NTN Thrust bearings
NTN bearing number nomenclature
Supplementary prefix code
- 4T: 4T tapered roller bearings
- ET: ET tapered roller bearings
- ETA: ET+special heat treatment
- E: Bearing using case hardened steel
- EA: Bearing made of nitride-treated case hardened steel
- TA: Bearing made of nitride-treated bearing steel (SUJ3)
- TM: Bearing made of special heat-treated bearing steel (SUJ3)
- F: Stainless steel bearings
- N: High speed steel bearings
- M: Plated bearings
- 5S: Ceramic rolling element bearings
- HL: HL roller bearings
- ECO: ECO-Top tapered roller bearings
- LH: Bearing made of bearing steel that provides long life at high temperatures (STJ2), which is treated to stabilize dimensions at temperatures up to 250°C
- TS3: Dimension stabilized bearing for high temperature use (to 200°C)
- TS4: Dimension stabilized bearing for high temperature use (to 250°C)
NTN bearing series
| Bearing series code | width/height series | diameter series |
|---|---|---|
| Deep groove ball bearings (type code 6) | ||
|
68 69 60 62 63 |
(1) (1) (1) (0) (0) |
8 9 0 2 3 |
| Angular contact ball bearings (type code 7) | ||
|
78 79 70 72 73 |
(1) (1) (1) (0) (0) |
8 9 0 2 3 |
| Self-aligning ball bearings (type code 1,2) | ||
|
12 13 22 23 |
(0) (0) (2) (2) |
2 3 2 3 |
| Cylindrical roller bearings (type code NU, N, NF, NNU, NN, etc.) | ||
|
NU10 NU2 NU22 NU3 NU23 NU4 NNU49 NN30 |
1 (0) 2 (0) 2 (0) 4 3 |
0 2 2 3 3 4 9 0 |
| Tapered roller bearings (type code 3) | ||
|
329X 320X 302 322 303 303D 313X 323 |
2 2 0 2 0 0 1 2 |
9 0 2 2 3 3 3 3 |
| Spherical roller bearings (type code 2) | ||
|
239 230 240 231 241 222 232 213 223 |
3 3 4 3 4 2 3 1 2 |
9 0 0 1 1 2 2 3 3 |
| Single direction thrust ball bearings (type code 5) | ||
|
511 512 513 514 |
1 1 1 1 |
1 2 3 4 |
| Cylindrical roller thrust bearings (type code 8) | ||
|
811 812 893 |
1 1 9 |
1 2 3 |
| Spherical thrust roller bearings (type code 2) | ||
|
292 293 294 |
9 |
2 3 4 |
Contact angle code
NTN angular contact ball bearings:
- (A): Standard contact angle 30°
- B: Standard contact angle 40°
- C: Standard contact angle 15°
NTN tapered roller bearings
- (B): Contact angle over 10° to/including 17°
- C: Contact angle over 17° to/including 24°
- D: Contact angle over 24° to/including 32°
Internal modifications code
- U: Internationally interchangeable tapered roller bearings
- R: Noninternationally interchangeable tapered roller bearings
- ST: Low torque tapered roller bearings
- HT: High axial load use cylindrical roller bearings
Cage code
- L1: High strength, machined brass cage
- F1: Machined carbon steel cage
- G1: High strength machined brass rivetless cage with square holes,
- G2: Pin type cage
- J: Pressed steel cage
- T2: Plastic mold cage
Seal / Shield code
- LLB: Synthetic rubber seal (noncontact type)
- LLU: Synthetic rubber seal (contact type)
- LLH: Synthetic rubber seal (low-torque type)
- ZZ: Steel shield
External configuration code
- K: Tapered inner ring bore, standard taper ratio 1:12
- K30: Tapered inner ring bore, standard taper ratio 1:30
- N: With snap ring groove
- NR: With snap ring
- D: With oil hole
- D1: Lubrication hole/lubrication groove
Duplex arrangement code
- DB: Back-to-back arrangement
- DF: Face-to-face arrangement
- DT: Tandem arrangement
- D2: Two matched, paired bearings
- G: Flush ground
Internal clearance / preload code
- C2: Internal clearance less than normal
- (CN): Normal clearance
- C3: Internal clearance greater than normal
- C4: Internal clearance greater than C3
- C5: Internal clearance greater than C4
- CM: Radial internal clearance for electric motor use
- /GL: Light preload
- /GN: Normal preload
- /GM: Medium preload
- /GH: Heavy preload
Tolerance code
- P6: JIS Class 6
- P5: JIS Class 5
- P4: JIS Class 4
- P2: JIS Class 2
- 2: ABMA Class 2
- 3: ABMA Class 3
- 0: ABMA Class 0
- 00: ABMA Class 00
Lubrication code
- /2AS: Shell Alvania S2 grease
- /3AS: Shell Alvania S3 grease
- /8A: Shell Alvania EP2 grease
- /5K: MULTEMP SRL
- /LX11: Barierta JFE552
- /LP03: Thermosetting grease (grease for poly-lube bearings)