6004 bearing: complete specifications & equivalents
The 6004 is a ISO 15 radial bearing sized 20 x 42 x 12 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Bore diameter d | 20 mm |
| Outer diameter D | 42 mm |
| Width B | 12 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN / C3 available |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 9.95 kN |
| Basic static load rating C0 | 5 kN |
| Fatigue load limit Pu | 0.212 kN |
| Reference speed (thermal) | 38000 rpm |
| Limiting speed (mechanical) | 24000 rpm |
| Operating temperature | -40 to +150 °C |
| Mass | 67 g |
| Manufacturer designation | SKF 6004 |
| Standard | ISO 15 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018) |
| Last verified | 2026-09-24 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018)) · extracted 2026-09-24
Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018)); SKF® and SKF Explorer® are trademarks of AB SKF, used here for identification only — mpnbase is not an authorized SKF distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at skf.com.
Dimensions in inches & 6000-series range
| Bore d | 0.787 in |
|---|---|
| Outer diameter D | 1.654 in |
| Width B | 0.472 in |
| ISO bore code | 04 |
| Radial section height (D−d)/2 | 11 mm |
| Smallest bore in 6000-series | 10 mm |
| Largest outer diameter in 6000-series | 420 mm |
| Width range across 6000-series | 8–65 mm |
| Bore position in 6000-series (smallest first) | 5 of 35 |
| Bore above smallest 6000-series size | 10 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 6004 | 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 6004 model number is decoded
In the 6000-series (ISO 15 diameter series 0) the last two digits encode the bore: 6004 carries bore code 04 = 20 mm. Outside diameter 42 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 20 mm shaft, typical catalogue practice is a k5 shaft seat with an H7 housing bore — verify against the actual load direction and magnitude. In the SKF catalogue this open execution carries the bare designation; protected variants are ordered separately as -2Z and -2RSH.
Typical equipment & failure modes
Common applications
- agricultural equipment
- fans and blowers
- electric motors
- centrifugal pumps
Known failure patterns
- contamination wear from dust and dirt ingress through the open arrangement
- lubricant starvation when no regreasing interval is maintained
- cage damage from operation beyond the limiting speed
- electrical pitting in VFD-driven motors without grounding protection
Selection pitfalls — read before you substitute
- At a 20 mm bore, a shaft-seat burr or an overtight setscrew can score the thin inner ring of 6004; check shaft finish and runout (target Ra ≤ 1.6 µm) before pressing it home.
- The 60xx extra-light section at 20 mm bore uses a smaller 42 mm OD than a 6204; load ratings are lower, so do not replace a failed 62-series bearing with a 60-series without re-rating the load.
- The open 6004 has no lubricant retention: grease escapes and contaminants migrate straight into the 20×42×12 mm raceway, so specify a sealed arrangement for dusty or washdown duty.
- Open bearings tolerate the highest speeds in the 6000-series but need a defined regreasing interval; run-to-failure lubrication is the dominant cause of early failure in open 6004 units.
- Suffixes stack in a defined order — clearance follows the seal code, e.g. 6004-C3. No clearance suffix means normal CN clearance.
- The open 6004 needs external sealing and application-supplied lubrication; in the SKF catalogue the protected variants are separate order numbers 6004-2Z (shields) and 6004-2RSH (contact seals), not suffix-free 6004.
- The 9.95/5 kN ratings here are SKF Explorer-class figures from catalogue PUB BU/P1 17000/1 EN (Oct 2018); SKF can revise internal geometry and ratings without changing the designation, so treat the catalogue version and date as part of the specification and re-verify for critical drives.
Frequently asked questions
What are the dimensions of a 6004 bearing?
A 6004 deep-groove ball bearing has a 20 mm bore, 42 mm outer diameter and 12 mm width (0.787 × 1.654 × 0.472 in), per ISO 15 boundary dimensions. It is an open bearing with no seals or shields. Geometry-based estimated mass is about 66 g for a steel-cage unit; catalogue masses vary slightly with seal and cage design.
How does the 6004 bore code work?
The last two digits of 6004 are bore code 04, giving 04 × 5 = 20 mm bore. The 42 mm outside diameter and 12 mm width follow the ISO 15 diameter series, not the bore code alone.
What does no suffix on 6004 mean?
A bare 6004 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 6000 compare with other series at the same 20 mm bore?
The second digit is the diameter series: 60 is the smallest standard section (42×12 mm, 11.0 mm radial section) at 20 mm bore — below 62/63/64 in load capacity, for light loads in compact spaces.
What is the SKF designation and catalogue data for 6004?
In the SKF Rolling Bearings catalogue this size is listed as 6004 — the open (unsealed) execution, 20×42×12 mm per ISO 15. Quoted values: C 9.95 kN, C0 5 kN, Pu 0.212 kN, limiting speed 24000 r/min, mass 67 g. Brand suffixes (2Z, 2RSH) differ from the industry-neutral spelling 6004.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018) on 2026-09-24. Read our editorial & correction policy.