6208-RSR bearing: complete specifications & equivalents
The 6208-RSR is a ISO 15 radial bearing sized 40 x 80 x 18 mm (bore x OD x width) with RSR sealing. Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 40 mm |
| Outer diameter D | 80 mm |
| Width B | 18 mm |
| Material | GCr15 |
| Seal / shield | RSR |
| Internal clearance | CN / C3 available |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 32.5 kN |
| Basic static load rating C0 | 19 kN |
| Fatigue load limit Pu | 0.8 kN |
| Reference speed (thermal) | 18000 rpm |
| Limiting speed (mechanical) | 9000 rpm |
| Operating temperature | -30 to +120 °C |
| Mass | 380 g |
| Manufacturer designation | SKF 6208-2RZ |
| Standard | ISO 15 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018) |
| Last verified | 2026-09-25 |
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 & 6200-series range
| Bore d | 1.575 in |
|---|---|
| Outer diameter D | 3.15 in |
| Width B | 0.709 in |
| ISO bore code | 08 |
| Radial section height (D−d)/2 | 20 mm |
| Smallest bore in 6200-series | 3 mm |
| Largest outer diameter in 6200-series | 540 mm |
| Width range across 6200-series | 2.5–85 mm |
| Bore position in 6200-series (smallest first) | 17 of 45 |
| Bore above smallest 6200-series size | 37 mm |
Mounting, lubrication & life for 6208-RSR
Recommended fits & mounting
- Rotating inner ring on a 40 mm shaft: k5; housing bore H7 for normal stationary-load outer rings. Reverse the logic if the outer ring rotates.
- Fit by induction heating (max 120 °C) where practical — never drive the ring home through the rolling elements.
- Keep shaft and housing fillet radii below the bearing chamfer so the 18 mm-wide ring seats square on its shoulder.
Lubrication strategy
Non-contact low-drag seal lips retain the factory grease but are not liquid-tight. Treat as grease-for-life in light, dry duty; in dirty or wet positions plan replacement around contamination rather than fatigue.
Worked L10 life example (illustrative duty)
For ball bearings, L10h = (C/P)3 · 106 / (60·n). Taking an example radial equivalent load P = 3 kN at n = 1,500 r/min (a small belted motor duty — substitute the real equivalent load from the application calculation):
C = 32.5 kN → L10h ≈ 14,127 hours
Choosing a section at the same 40 mm bore
| Series | Open execution | OD × width | C (kN) | Limiting speed (r/min) |
|---|---|---|---|---|
| 60xx | 6008-FAG | 68 × 15 | 17.8 | 14,600 |
| 62xx | 6208-FAG | 80 × 18 | 31.5 | 13,600 |
| 63xx | 6308-FAG | 90 × 23 | 47.0 | 11,800 |
| 64xx | 6408-FAG | 110 × 27 | 68.0 | 9,500 |
| 618xx | 61808-FAG | 52 × 7 | 4.9 | 19,300 |
| 619xx | 61908-FAG | 62 × 12 | 14.5 | 15,800 |
| 160xx | 16008 | 68 × 9 | 12.6 | 15,200 |
A larger section is not a drop-in swap — OD and width change — and same-envelope seal variants are compared on the 40×80×18 envelope page. Match meaning, not the size chart alone: see what the cross-reference levels mean.
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 6208-2RS-FAG | FAG | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 40×80×18 mm envelope per ISO 15; seal variant differs (RSR vs 2RS) — confirm sealing suits the duty. |
| 6208-FAG | FAG | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 40×80×18 mm envelope per ISO 15; seal variant differs (RSR vs OPEN) — confirm sealing suits the duty. |
| 6208-ZZ-FAG | FAG | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 40×80×18 mm envelope per ISO 15; seal variant differs (RSR vs ZZ) — confirm sealing suits the duty. |
| 6208 | ISO 15 | verify Commonly quoted cross reference; confirm against the target catalog before ordering. | ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting. |
| 6208-2RS-NSK | NSK | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 40×80×18 mm envelope per ISO 15; seal variant differs (RSR vs 2RS) — confirm sealing suits the duty. |
| 6208-NSK | NSK | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 40×80×18 mm envelope per ISO 15; seal variant differs (RSR vs OPEN) — confirm sealing suits the duty. |
| 6208-RSR-NSK | NSK | full Dimensions and internal design equivalent — standard interchange. | Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier. |
| 6208-ZZ-NSK | NSK | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 40×80×18 mm envelope per ISO 15; seal variant differs (RSR vs ZZ) — confirm sealing suits the duty. |
| 6208-2RS-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 40×80×18 mm envelope per ISO 15; seal variant differs (RSR vs 2RS) — confirm sealing suits the duty. |
| 6208-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 40×80×18 mm envelope per ISO 15; seal variant differs (RSR vs OPEN) — confirm sealing suits the duty. |
| 6208-RSR-NTN | NTN | full Dimensions and internal design equivalent — standard interchange. | Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier. |
| 6208-ZZ-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 40×80×18 mm envelope per ISO 15; seal variant differs (RSR vs ZZ) — confirm sealing suits the duty. |
| 7208 | SKF | verify Commonly quoted cross reference; confirm against the target catalog before ordering. | — |
| NU208 | SKF | verify Commonly quoted cross reference; confirm against the target catalog before ordering. | — |
| W6208-2RS | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | SKF stainless execution W 6208-2RS1 shares the 40×80×18 mm envelope but rates differently (32.5/19 kN vs 25.1/17.6 kN) — not a load-rating equivalent. |
| W6208-ZZ | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | SKF stainless execution W 6208-2Z shares the 40×80×18 mm envelope but rates differently (32.5/19 kN vs 25.1/17.6 kN) — not a load-rating equivalent. |
| W6208 | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | SKF stainless execution W 6208 shares the 40×80×18 mm envelope but rates differently (32.5/19 kN vs 25.1/17.6 kN) — not a load-rating equivalent. |
| 208 | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | SKF 208 shares the 40×80×18 mm envelope but catalogue C/C0 differ — envelope match only after a load check. |
| 208-ZZ | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | SKF 208-2Z shares the 40×80×18 mm envelope but catalogue C/C0 differ — envelope match only after a load check. |
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 6208-RSR model number is decoded
6208-RSR uses two non-contact elastomer lips with very low drag; coarse debris stays out, but the bearing is not liquid-tight. Within the light 62xx section (diameter series 2 of ISO 15), multiplying bore code 08 by five gives the 40 mm bore; the 80 mm outside diameter and 18 mm width follow the same boundary-dimension plan. For a rotating inner ring on a 40 mm shaft under normal load, catalogue practice seats it on a k5 shaft fit with an H7 housing bore — confirm against the actual load direction and magnitude before committing. SKF's low-friction seal suffix is 2RSL/2RZ (this page's industry-neutral spelling is -RSR); catalogue number 6208-2RZ.
Typical equipment & failure modes
Common applications
- fans and blowers
- electric motors
- centrifugal pumps
- small gearboxes
Known failure patterns
- ingress of fine dust or moisture past the non-contact lip in dirty or wet duty (RSR is not liquid-tight)
- lip-lubricant starvation if the bearing runs dry for extended periods
- 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 40 mm bore, a shaft-seat burr or an overtight setscrew can score the thin inner ring of 6208-RSR; check shaft finish and runout (target Ra ≤ 1.6 µm) before pressing it home.
- At 40 mm bore the 62xx light series is the workhorse section; its 80×18 mm envelope is what most motor and gearbox seats are machined for, so any alternative section must be checked against both this OD and this width, not the bore alone.
- RSR low-friction seals on 6208-RSR run faster than contact-seal 6208-2RS but let fine dust and moisture past the non-contact lip; in dirty or wet duty specify 6208-2RS instead.
- The low-drag lip of 6208-RSR barely touches the inner ring; after long shelf storage the grease can separate, so rotate the rings by hand and confirm smooth, silent running before fitting.
- Grease compatibility is not guaranteed between fills: mixing lithium and polyurea thickeners in a 6200-series position can soften the mixture and leak — clean out the old fill before switching grease types.
- Vibration during standstill brinells the raceways of a 40 mm bearing at ball spacing; if the machine sits idle next to running equipment, turn the shaft over periodically or isolate the arrangement.
- SKF catalogues the low-friction seal as 6208-2RZ (suffix -2RSL or -2RZ): a non-contact elastomer lip that runs near the open 9000 r/min limiting speed, closer to the open bearing's 18000 r/min reference than the contact-seal version. It keeps coarse debris out without the drag of a contact seal, but is not liquid-tight — use 2RSH for wet or fine-dust positions.
- The 32.5/19 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 6208-RSR bearing?
A 6208-RSR deep-groove ball bearing has a 40 mm bore, 80 mm outer diameter and 18 mm width (1.575 × 3.15 × 0.709 in), per ISO 15 boundary dimensions. It is fitted with two low-friction non-contact rubber seals.
What internal clearance does 6208-RSR have?
Unless a clearance suffix says otherwise, 6208-RSR 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 6208 and verify the residual clearance after mounting.
How should 6208-RSR be mounted?
Apply the mounting force to the ring being fitted: on a 40 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 lubrication does 6208-RSR need?
6208-RSR is supplied pre-greased for life and is not designed to be opened for relubrication; where a relubrication path is required, specify the open 6208 with a housing grease fitting instead.
What is the SKF designation and catalogue data for 6208-RSR?
In the SKF Rolling Bearings catalogue this size is listed as 6208-2RZ — two low-friction non-contact elastomer seals, 40×80×18 mm per ISO 15. Quoted values: C 32.5 kN, C0 19 kN, Pu 0.8 kN, limiting speed 9000 r/min, mass 380 g. Brand suffixes (2Z, 2RSH, 2RSL) differ from the industry-neutral spelling 6208-RSR.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018) on 2026-09-25. Read our editorial & correction policy.