6400 bearing: complete specifications & equivalents
The 6400 is a ISO 15 radial bearing sized 10 x 40 x 12 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Bore diameter d | 10 mm |
| Outer diameter D | 40 mm |
| Width B | 12 mm |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Mass (geometry estimate) | 72 g |
| Standard | ISO 15 |
| Catalog version | iso15-ed4-geometry |
| Last verified | 2026-09-24 |
Source: ISO 15 boundary-dimensions standard · extracted 2026-09-24
Standard-interchange bearing: dimensions per ISO 15; CN clearance, P0 tolerance and a stamped-steel cage are catalogue defaults unless the supplier states otherwise, and mass is a geometry-derived estimate. Brand catalogue load ratings and limiting speeds for 6400 are being backfilled — use the inquiry form for certified values.
Dimensions in inches & 6400-series range
| Bore d | 0.394 in |
|---|---|
| Outer diameter D | 1.575 in |
| Width B | 0.472 in |
| ISO bore code | 00 |
| Radial section height (D−d)/2 | 15 mm |
| Smallest bore in 6400-series | 10 mm |
| Largest outer diameter in 6400-series | 250 mm |
| Width range across 6400-series | 12–58 mm |
| Bore position in 6400-series (smallest first) | 1 of 21 |
| Bore above smallest 6400-series size | 0 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 6400 | ISO 15 | full Dimensions and internal design equivalent — standard interchange. | ISO 15 boundary-dimension envelope; brand-specific OEM equivalents (NSK/FAG/NTN) pending multi-source data. |
Interchange levels: full standard interchange · partial verify parameters · verify manual confirmation required. Links resolve to the equivalent model's specification page where available.
How the 6400 model number is decoded
In the 6400-series (ISO 15 diameter series 4) the last two digits encode the bore: 6400 carries bore code 00 = 10 mm. Codes 00–03 follow the 10/12/15/17 mm exception table rather than code × 5. Outside diameter 40 mm and width 12 mm come from the ISO 15 boundary-dimensions general plan. With no seal suffix the bearing is open: no shields or seals are fitted and lubrication is supplied by the application. For normal-load mounting with a rotating inner ring on a 10 mm shaft, typical catalogue practice is a j5 shaft seat with an H7 housing bore — verify against the actual load direction and magnitude.
Typical equipment & failure modes
Common applications
- fractional-horsepower electric motors
- domestic appliances
- power tools
- small fans and blowers
Known failure patterns
- contamination wear from dust and dirt ingress through the open arrangement
- lubricant starvation when no regreasing interval is maintained
- fretting corrosion on a loose shaft seat
- cage damage from operation beyond the limiting speed
Selection pitfalls — read before you substitute
- Bore codes 00–03 use the exception table: 6400 fits a 10 mm shaft — the code × 5 mnemonic does not apply below code 04 (it would imply 0 mm for code 00).
- The 64xx heavy section at 10 mm bore (40 mm OD) is built for high-load, lower-speed duty; specifying it in a high-rpm motor gives excess heat and short grease life — use 62/63 there.
- The open 6400 has no lubricant retention: grease escapes and contaminants migrate straight into the 10×40×12 mm raceway, so specify a sealed arrangement for dusty or washdown duty.
- Open bearings tolerate the highest speeds in the 6400-series but need a defined regreasing interval; run-to-failure lubrication is the dominant cause of early failure in open 6400 units.
- Do not quieten a noisy bearing by preloading it: the 6400-series is a deep-groove design, not angular-contact; axial preload raises temperature and shortens grease life.
Frequently asked questions
What are the dimensions of a 6400 bearing?
A 6400 deep-groove ball bearing has a 10 mm bore, 40 mm outer diameter and 12 mm width (0.394 × 1.575 × 0.472 in), per ISO 15 boundary dimensions. It is an open bearing with no seals or shields. Geometry-based estimated mass is about 72 g for a steel-cage unit; catalogue masses vary slightly with seal and cage design.
Why does 6400 not follow the bore-code × 5 rule?
Codes 00–03 use the exception table (10, 12, 15 and 17 mm): 6400 with code 00 has a 10 mm bore. The code × 5 convention starts at code 04 (20 mm).
What does no suffix on 6400 mean?
A bare 6400 designation means open: no shields or seals, normal CN radial clearance and P0 normal tolerance unless further suffixes are ordered. The application must supply and retain the lubrication.
How does the 6400 compare with other series at the same 10 mm bore?
The '4' is the heavy diameter series: 40×12 mm, 15.0 mm radial section at 10 mm bore — the highest-capacity single-row 6xx option here, aimed at lower-speed, high-load shafts.
Are 6400 bearings from different brands interchangeable?
For boundary dimensions, yes: every brand's 6400 uses the same ISO 15 envelope (10×40×12 mm). Load ratings, limiting speeds, clearance, precision class and sealing design can differ, so verify those in the supplier catalogue when substituting.
Reviewed & verified by the MPN Base engineering desk against source catalog iso15-ed4-geometry on 2026-09-24. Read our editorial & correction policy.