61805-2RS bearing: complete specifications & equivalents
The 61805-2RS is a ISO 15 radial bearing sized 25 x 37 x 7 mm (bore x OD x width) with 2RS sealing. Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 25 mm |
| Outer diameter D | 37 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 | 4.36 kN |
| Basic static load rating C0 | 2.6 kN |
| Fatigue load limit Pu | 0.125 kN |
| Limiting speed (mechanical) | 11000 rpm |
| Operating temperature | -30 to +110 °C |
| Mass | 22 g |
| Manufacturer designation | SKF 61805-2RS1 |
| 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 | 0.984 in |
|---|---|
| Outer diameter D | 1.457 in |
| Width B | 0.276 in |
| ISO bore code | 05 |
| Radial section height (D−d)/2 | 6 mm |
| Smallest bore in 61800-series | 1 mm |
| Largest outer diameter in 61800-series | 1820 mm |
| Width range across 61800-series | 1–140 mm |
| Bore position in 61800-series (smallest first) | 16 of 74 |
| Bore above smallest 61800-series size | 24 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 61805-2RS-FAG | FAG | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 25×37×7 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting. |
| 61805-FAG | FAG | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 25×37×7 mm envelope per ISO 15; seal variant (2RS vs OPEN) and load ratings differ — confirm sealing and rating before substituting. |
| 61805-ZZ-FAG | FAG | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 25×37×7 mm envelope per ISO 15; seal variant (2RS vs ZZ) and load ratings differ — confirm sealing and rating before substituting. |
| 61805-2RS-NSK | NSK | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 25×37×7 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting. |
| 61805-NSK | NSK | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 25×37×7 mm envelope per ISO 15; seal variant (2RS vs OPEN) and load ratings differ — confirm sealing and rating before substituting. |
| 61805-RSR-NSK | NSK | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 25×37×7 mm envelope per ISO 15; seal variant (2RS vs RSR) and load ratings differ — confirm sealing and rating before substituting. |
| 61805-ZZ | NSK | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 25×37×7 mm envelope per ISO 15; seal variant (2RS vs ZZ) and load ratings differ — confirm sealing and rating before substituting. |
| 61805-2RS-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 25×37×7 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting. |
| 61805-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 25×37×7 mm envelope per ISO 15; seal variant (2RS vs OPEN) and load ratings differ — confirm sealing and rating before substituting. |
| 61805-RSR-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 25×37×7 mm envelope per ISO 15; seal variant (2RS vs RSR) and load ratings differ — confirm sealing and rating before substituting. |
| 61805-ZZ-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 25×37×7 mm envelope per ISO 15; seal variant (2RS vs ZZ) and load ratings differ — confirm sealing and rating before substituting. |
| W61805-2RS | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | SKF stainless execution W 61805-2RS1 shares the 25×37×7 mm envelope but rates differently (4.36/2.6 kN vs 3.38/2.5 kN) — not a load-rating equivalent. |
| W61805-ZZ | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | SKF stainless execution W 61805-2Z shares the 25×37×7 mm envelope but rates differently (4.36/2.6 kN vs 3.38/2.5 kN) — not a load-rating equivalent. |
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 61805-2RS model number is decoded
In the 61800-series (diameter series 8 of ISO 15) the last two digits encode the bore: 61805 carries bore code 05 = 25 mm. Outside diameter 37 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 25 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 61805-2RS1 (older text: -2RS1), mapped here from the industry-neutral -2RS spelling.
Typical equipment & failure modes
Common applications
- robotics and automation joints
- lay shafts and idler shafts
- textile machinery
- packaging machinery
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)
- brinelling from static overload or hammering during mounting
- false brinelling from vibration while the shaft is stationary
Selection pitfalls — read before you substitute
- Sizes around 25 mm bore are normally pressed on cold with a sleeve against the inner-ring face; the press force must never route through the outer ring or the balls of 61805-2RS.
- The 618xx thin section at 25 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 6205.
- Contact seals add drag and heat: 61805-2RS runs slower and cooler-limited than the open 61805; rubber lips are generally limited to roughly 80–110 °C continuous depending on grease, and C3 clearance is the common hot-duty choice.
- Heat is the enemy of the sealed 61805-2RS: sustained running near the lip temperature limit hardens the rubber, after which grease escapes and dirt tracks in — watch the housing temperature in hot drives.
- Never mix components between two 61805-2RS units: rings, cage and balls are factory-matched and are not field-interchangeable, even between identical designations.
- 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 61805-2RS1 (older printings may read -2RS1); it is shipped pre-greased and its 11000 r/min limiting speed is set by seal-lip drag and grease life versus the open bearing's 38000 r/min thermal reference speed.
- The 4.36/2.6 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 61805-2RS bearing?
A 61805-2RS deep-groove ball bearing has a 25 mm bore, 37 mm outer diameter and 7 mm width (0.984 × 1.457 × 0.276 in), per ISO 15 boundary dimensions. It is fitted with two contact rubber seals and is normally pre-greased.
Are 61805 bearings from different brands interchangeable?
For boundary dimensions, yes: every brand's 61805 uses the same ISO 15 envelope (25×37×7 mm). Load ratings, limiting speeds, clearance, precision class and sealing design can differ, so verify those in the supplier catalogue when substituting. Seal suffixes also differ by brand (2RS, DDU, LLU, 2RSL and similar).
What internal clearance does 61805-2RS have?
Unless a clearance suffix says otherwise, 61805-2RS is manufactured to normal (CN) radial internal clearance. Tight fits and hot shafts consume clearance in service — for those conditions order the C3 execution of 61805 and verify the residual clearance after mounting.
How should 61805-2RS be mounted?
Apply the mounting force to the ring being fitted: on a 25 mm shaft seat the press load must pass through the inner-ring face only. A fitting sleeve and an arbor press are normally sufficient at this size. Never strike the outer ring, the cage or the seals.
What is the SKF designation and catalogue data for 61805-2RS?
In the SKF Rolling Bearings catalogue this size is listed as 61805-2RS1 — two contact elastomer seals over a lifetime grease fill, 25×37×7 mm per ISO 15. Quoted values: C 4.36 kN, C0 2.6 kN, Pu 0.125 kN, limiting speed 11000 r/min, mass 22 g. Brand suffixes (2Z, 2RSH, 2RSL) differ from the industry-neutral spelling 61805-2RS.
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.