3306-A-2RS1 bearing: complete specifications & equivalents
The 3306-A-2RS1 is a ISO 15 radial bearing sized 30 x 72 x 30.2 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 | 30 mm |
| Outer diameter D | 72 mm |
| Width B | 30.2 mm |
| Material | GCr15 |
| Seal / shield | 2RS |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 42.5 kN |
| Basic static load rating C0 | 30 kN |
| Fatigue load limit Pu | 1.27 kN |
| Limiting speed (mechanical) | 6300 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 520 g |
| Manufacturer designation | 3306 A-2RS1 |
| Standard | ISO 15 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018) |
| Last verified | 2026-09-27 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018)) · extracted 2026-09-27
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 & 3300-series range
| Bore d | 1.181 in |
|---|---|
| Outer diameter D | 2.835 in |
| Width B | 1.189 in |
| ISO bore code | 06 |
| Radial section height (D−d)/2 | 21 mm |
| Smallest bore in 3300-series | 15 mm |
| Largest outer diameter in 3300-series | 240 mm |
| Width range across 3300-series | 19–92.1 mm |
| Bore position in 3300-series (smallest first) | 5 of 20 |
| Bore above smallest 3300-series size | 15 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 3306-A | SKF | full Dimensions and internal design equivalent — standard interchange. | Same 30×72×30.2 mm envelope with catalogue ratings within 10 %; 3306 A is the stamped steel cage, open arrangement execution of this size — boundary dimensions interchangeable, execution differs. |
| 3306-ATN9 | SKF | full Dimensions and internal design equivalent — standard interchange. | Same 30×72×30.2 mm envelope with catalogue ratings within 10 %; 3306 ATN9 is the glass-fibre PA66 cage, open arrangement execution of this size — boundary dimensions interchangeable, execution differs. |
| 3306-A-2Z | SKF | full Dimensions and internal design equivalent — standard interchange. | Same 30×72×30.2 mm envelope with catalogue ratings within 10 %; 3306 A-2Z is the stamped steel cage, shields (-2Z) execution of this size — boundary dimensions interchangeable, execution differs. |
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 3306-A-2RS1 model number is decoded
3306 A-2RS1 is the capped double-row angular-contact ball bearing for a 30 mm shaft, 30×72×30.2 mm, greased and sealed (or shielded) for life at the SKF works. A on this double-row bearing means no filling slots, so both ball rows retain their full complement. -2RS1 marks a contact NBR elastomer seal on each side, riding the inner ring: better fine-dust and moisture protection than a shield at the cost of seal drag and a lower speed ceiling. Envelope 30×72×30.2 mm (1.181×2.835×1.189 in), 21.0 mm radial section height, C 42.5 kN, C0 30 kN, Pu 1.27 kN.SKF publishes only the 6,300 r/min limiting speed for this execution, catalogue mass 520 g. Envelope economics: the 30.2 mm width over a 21.0 mm section yields 1.44 mm of ring width per section millimetre, and the bearing weighs 520 g for 42.5 kN of dynamic capacity — about 12 g per rated kN. Selection figures for 3306 A-2RS1: the static-to-dynamic ratio C0/C is 0.71, Pu 1.27 kN is about 3 % of C, and catalogue mass works out to roughly 17 g per millimetre of bore. Bore-to-OD planning: OD 72 over bore 30 is a 2.40× step for this size, and the 30.2 mm width gives a bore/width ratio of 0.99; use these ratios when housing space around the 30 mm shaft is the first constraint. Contact-seal execution note: the two NBR -2RS1 lips ride the inner-ring lands, sealing the factory grease against moisture and fine dust; the lips add running torque and set the lower limiting speed printed for this size, and the sealed cavity is maintenance-free by design (no relubrication path). The A-2Z shielded order number is the low-drag alternative for cleaner positions.
Typical equipment & failure modes
Common applications
- material-handling equipment
- lifetime-lubricated electric motor and gearbox positions
- agricultural machinery drives
Known failure patterns
- fine dust or moisture bypassing a worn 2RS1 lip in dirty or wet duty
- shield rubbing after misalignment or overheating of a 2Z execution
- seal-lip wear and grease loss after fine abrasive dust reaches the lip contact
- snap-ring groove or two-piece-ring damage when the D execution is pressed home through the wrong ring
- hard-particle indentation of the asymmetric raceway in unfiltered oil
- hard-particle indentation of the asymmetric raceway in unfiltered oil
Selection pitfalls — read before you substitute
- Never wash 3306-A-2RS1 in solvent: the lifetime grease fill cannot be replaced once flushed out.
- Open 3306 and capped 3306-A-2RS1 share the 30×72×30.2 mm envelope and 42.5/30 kN ratings — the choice is maintenance access and contamination, not capacity.
- Open 3306 and capped 3306-A-2RS1 share the 30×72×30.2 mm envelope and 42.5/30 kN ratings — the choice is maintenance access and contamination, not capacity.
- The contact NBR seals add drag and a lower speed ceiling: no relubrication is provided for, so mounting cleanliness decides much of the real grease life.
- Catalogue ratings are SKF PUB BU/P1 17000 figures for 3306 A-2RS1 as the double contactsealed execution; the other order numbers of the 3306 size are different products and may carry different ratings — always quote the full designation when purchasing.
Frequently asked questions
What are the dimensions and catalogue data of 3306-A-2RS1?
3306 A-2RS1 measures 30 mm bore × 72 mm OD × 30.2 mm width (1.181 × 2.835 × 1.189 in), mass about 520 g. SKF 17000 ratings: C 42.5 kN, C0 30 kN, Pu 1.27 kN, SKF publishes only the 6,300 r/min limiting speed for this execution.
What does the A-2RS1 suffix mean?
A on this double-row bearing means no filling slots, so both ball rows retain their full complement. -2RS1 marks a contact NBR elastomer seal on each side, riding the inner ring: better fine-dust and moisture protection than a shield at the cost of seal drag and a lower speed ceiling.
What is the difference between 3306 A-2Z and A-2RS1?
Both share the double-row A geometry, dimensions and ratings; A-2Z uses non-contact metal shields (lower drag, higher speed, dust protection), A-2RS1 uses contact NBR rubber seals (better moisture and fine-dust protection, lower speed ceiling and more drag).
Can I wash or repack a capped 3306?
No — solvent flushes the factory grease with no way to replace it fully; keep the original protection in place and mount the bearing with clean tools.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018) on 2026-09-27. Read our editorial & correction policy.