The nomenclature of NSK miniature ball bearings are part of NSK bearing nomenclature, that be alphanumeric combinations that indicate the NSK bearing type, boundary dimensions, dimensional and running accuracies, internal clearance, and other related specifications.
Examples of NSK miniature ball bearings
NSK basic number nomenclature
| NSK bearing series symbols | Bore number or size number | Contact angle symbol | |||
|---|---|---|---|---|---|
| Symbol | Meaning | Number | Meaning | Symbol | Meaning |
| 68 | Single-row deep groove ball bearings | 1 | Bearing bore 1mm | Angular contact ball bearings | |
| 69 | 2 | Bearing bore 2mm | A | Standard contact angle of 30° | |
| 60 |
3 ... |
Bearing bore 3mm | A5 | Standard contact angle of 25° | |
| 62 | 1X | Bearing bore 1.5mm | B | Standard contact angle of 40° | |
| 63 |
2X ... |
Bearing bore 2.5mm | C | Standard contact angle of 15° | |
| F68 | Deep groove ball bearings with flanged outer rings | 1 | Bearing bore 1mm | ||
| F69 | 2 | Bearing bore 2mm | |||
| F60 |
3 ... |
Bearing bore 3mm | |||
| F62 | 1X | Bearing bore 1.5mm | |||
| F63 |
2X ... |
Bearing bore 2.5mm | |||
| 70 | Single-row angular contact ball bearings | ||||
| 72 | |||||
| Special metric design | |||||
| MR | Single row deep groove ball bearings | 84 |
Brg O.D. 8mm Brg bore 4mm |
||
| MF | Deep groove ball bearings with flanged out rings |
148 ... |
Brg O.D. 14mm Brg bore 8mm |
||
| SMT | Thin-section deep groove ball bearings | 41X |
Brg O.D. 4mm Brg bore 1.2mm |
||
|
82X ... |
Brg O.D. 8mm Brg bore 2.5mm |
||||
| Inch disign | |||||
| R | single row deep groove ball bearings | 133 |
Brg O.D. 4.762mm(3/16 inch) Brg bore 2.38mm(3/32 inch) |
||
| SR..X | Ball bearings for synchros | 155 |
Brg O.D. 7.938mm(5/16 inch) Brg bore 3.967(5/32 inch) |
||
| RW | Deep groove ball bearings with extended inner rings |
2 ... |
Brg O.D. 9.525mm(3/8 inch) Brg bore 3.175mm(1/8 inch) |
||
| FRW | Deep groove ball bearings with extended inner rings, flanged | ||||
NSK supplementary number (suffixes)
Internal design symbol
- A: Internal design differs
- B: From standard one
Material symbol
- Omitted: high carbon chromium bearing steel SUJ 2 Equivalent to ASTM A295 52100
- h: Stainless steel Equivalent to SAE J405 51440C
- s: Stainless steel for special metric and inch designs "S" is prefix to series symbol
Cage symbol
- J: Pressed steel ribbon cage
- W: pressed steel snap cage
- T12 / T1X: Plastic snap cage
Seals, shields symbol
- Z / Z1: Shield on one side only
- ZZ/ZZ1: shields on both sides
- D: contact rubber seal on one side only
- DD: contact rubber seal on both side
- V: non-contact rubber seal on one side only
- VV: non-contact rubber seal on both side
Internal clearance symbol
- MC1: clearance less than MC2
- MC2: clearance less than MC3
- MC3: upgrade normal clearance
- MC4: clearance greater than MC3
- MC5: clearance greater than MC4
- MC6: clearance greater than MC5
Noise level symbol
- Omitted: standard
- E: Quieter than standard
- ER: Quieter than E
Accuracy class symbol
- Omitted: Normal
- P6: class 6
- P5: class 5
- P4: class 4
- Omitted: ANSI / ABMA ABEC 1
- 3: ANSI / ABMA ABEC 3
- 5P: ANSI / ABMA instrument ball bearings inch design CLASS 5P
- 7P: ANSI / ABMA instrument ball bearings design CLASS 7P
- 9P: ANSI / ABMA instrument ball bearings inch design 9P
Torque symbol
- Omitted: Standard
- L: low torque
Special specification symbol
- U1: special specification
- U2...
- UC1: Bore diameter is sorted into two groups
- UC2: outside diameter is sorted into two groups
- UC3: both bore and outside diameters are sorted into two groups
Lubricant symbol
- AF2: AEROSHELL FLUID 12
- NS7: NS HI-LUBE
- PS2: MULTEMP PS No.2
Lubricant quantity symbol
- Q: oil soaking
- K: grease packed less than L
- L: standard grease packing quantity
- S: grease packed more than L
- H: grease packed more than S
- M: grease packed more than H
