61804-2RS bearing: complete specifications & equivalents
The 61804-2RS is a ISO 15 radial bearing sized 20 x 32 x 7 mm (bore x OD x width) with 2RS sealing. Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Bore diameter d | 20 mm |
| Outer diameter D | 32 mm |
| Width B | 7 mm |
| Material | GCr15 |
| Seal / shield | 2RS |
| Internal clearance | CN / C3 available |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 4.03 kN |
| Basic static load rating C0 | 2.32 kN |
| Fatigue load limit Pu | 0.104 kN |
| Limiting speed (mechanical) | 13000 rpm |
| Operating temperature | -30 to +110 °C |
| Mass | 18 g |
| Manufacturer designation | SKF 61804-2RS1 |
| 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 & 61800-series range
| Bore d | 0.787 in |
|---|---|
| Outer diameter D | 1.26 in |
| Width B | 0.276 in |
| ISO bore code | 04 |
| Radial section height (D−d)/2 | 6 mm |
| Smallest bore in 61800-series | 10 mm |
| Largest outer diameter in 61800-series | 420 mm |
| Width range across 61800-series | 5–38 mm |
| Bore position in 61800-series (smallest first) | 5 of 39 |
| Bore above smallest 61800-series size | 10 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 61804-ZZ | GENERIC-ISO | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 20×32×7 mm envelope per ISO 15; seal variant differs (2RS vs ZZ) — confirm sealing suits the duty. |
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 61804-2RS model number is decoded
In the 61800-series (ISO 15 diameter series 8) the last two digits encode the bore: 61804 carries bore code 04 = 20 mm. Outside diameter 32 mm and width 7 mm come from the ISO 15 boundary-dimensions general plan. Suffix -2RS denotes two contact-type elastomer seals over a lifetime grease fill; the sealing lips add drag compared with open or shielded versions. 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. SKF's contact-seal catalogue number is 61804-2RS1 (older text: -2RS1), mapped here from the industry-neutral -2RS spelling.
Typical equipment & failure modes
Common applications
- space-constrained gearboxes
- clutch and transmission assemblies
- robotics and automation joints
- lay shafts and idler shafts
Known failure patterns
- seal-lip hardening and loss of pre-grease in sustained high-temperature service
- grease-life expiry in the sealed-for-life cavity (no relubrication path)
- raceway smearing under marginal lubrication at start-up
- edge loading from shaft deflection or housing misalignment
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 61804-2RS; check shaft finish and runout (target Ra ≤ 1.6 µm) before pressing it home.
- The 618xx thin section at 20 mm bore has only a 6.0 mm radial section height: it saves space but is highly sensitive to misalignment, shaft deflection and shock loads — verify shaft stiffness before choosing it over a 6204.
- Contact seals add drag and heat: 61804-2RS runs slower and cooler-limited than the open 61804; rubber lips are generally limited to roughly 80–110 °C continuous depending on grease, and C3 clearance is the common hot-duty choice.
- Never wash a sealed 61804-2RS in solvent or press it home via the outer ring; solvent destroys the grease thickener and mounting force through the seal deforms the lip.
- Shaft and housing fillets must clear the bearing chamfer so the 7 mm-wide ring seats square; provide an undercut or withdrawal groove instead of relying on an oversized radius.
- SKF catalogues the contact-sealed version as 61804-2RS1 (older printings may read -2RS1); it is shipped pre-greased and its 13000 r/min limiting speed is set by seal-lip drag and grease life versus the open bearing's 45000 r/min thermal reference speed.
- The 4.03/2.32 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 61804-2RS bearing?
A 61804-2RS deep-groove ball bearing has a 20 mm bore, 32 mm outer diameter and 7 mm width (0.787 × 1.26 × 0.276 in), per ISO 15 boundary dimensions. It is fitted with two contact rubber seals and is normally pre-greased. Geometry-based estimated mass is about 18 g for a steel-cage unit; catalogue masses vary slightly with seal and cage design.
How does the 61804 bore code work?
The last two digits of 61804 are bore code 04, giving 04 × 5 = 20 mm bore. The 32 mm outside diameter and 7 mm width follow the ISO 15 diameter series, not the bore code alone.
What does the 2RS suffix on 61804-2RS mean?
2RS means two contact elastomer seals, one each side, usually over a lifetime grease fill. Sealing against dust and moisture is better than ZZ shields, but the lip drag lowers the speed and temperature ceiling.
How does the 61800 compare with other series at the same 20 mm bore?
618 is an extra-thin section: 32×7 mm, only 6.0 mm radial section at 20 mm bore, far smaller than a 6204, for space-limited layouts at the cost of load rating and misalignment tolerance.
What is the SKF designation and catalogue data for 61804-2RS?
In the SKF Rolling Bearings catalogue this size is listed as 61804-2RS1 — two contact elastomer seals over a lifetime grease fill, 20×32×7 mm per ISO 15. Quoted values: C 4.03 kN, C0 2.32 kN, Pu 0.104 kN, limiting speed 13000 r/min, mass 18 g. Brand suffixes (2Z, 2RSH) differ from the industry-neutral spelling 61804-2RS.
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.