3209-ATN9 bearing: complete specifications & equivalents
The 3209-ATN9 is a ISO 15 radial bearing sized 45 x 85 x 30.2 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 45 mm |
| Outer diameter D | 85 mm |
| Width B | 30.2 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | polymer (PA66 glass-fibre reinforced) |
| Basic dynamic load rating C | 51 kN |
| Basic static load rating C0 | 39 kN |
| Fatigue load limit Pu | 1.63 kN |
| Reference speed (thermal) | 8500 rpm |
| Limiting speed (mechanical) | 7500 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 630 g |
| Manufacturer designation | 3209 ATN9 |
| 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 & 3200-series range
| Bore d | 1.772 in |
|---|---|
| Outer diameter D | 3.346 in |
| Width B | 1.189 in |
| ISO bore code | 09 |
| Radial section height (D−d)/2 | 20 mm |
| Smallest bore in 3200-series | 10 mm |
| Largest outer diameter in 3200-series | 200 mm |
| Width range across 3200-series | 14–69.8 mm |
| Bore position in 3200-series (smallest first) | 10 of 22 |
| Bore above smallest 3200-series size | 35 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 3209-A | SKF | full Dimensions and internal design equivalent — standard interchange. | Same 45×85×30.2 mm envelope with catalogue ratings within 10 %; 3209 A is the stamped steel cage, open arrangement execution of this size — boundary dimensions interchangeable, execution differs. |
| 3209-A-2Z | SKF | full Dimensions and internal design equivalent — standard interchange. | Same 45×85×30.2 mm envelope with catalogue ratings within 10 %; 3209 A-2Z is the stamped steel cage, shields (-2Z) execution of this size — boundary dimensions interchangeable, execution differs. |
| 3209-A-2RS1 | SKF | full Dimensions and internal design equivalent — standard interchange. | Same 45×85×30.2 mm envelope with catalogue ratings within 10 %; 3209 A-2RS1 is the stamped steel cage, contact NBR seals (-2RS1) 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 3209-ATN9 model number is decoded
3209 ATN9 is SKF's 45 mm-bore double-row angular-contact ball bearing of the 3200 series — two ball rows back-to-back for two-direction axial location in one unit, 45×85×30.2 mm. A on a double-row bearing means no filling slots, so both rows carry their full ball complement in both directions. glass-fibre reinforced PA66 cage, ball-centred (suffix TN9), with a 120 °C continuous-temperature ceiling. Envelope 45×85×30.2 mm (1.772×3.346×1.189 in), 20.0 mm radial section height, C 51 kN, C0 39 kN, Pu 1.63 kN.reference speed 8,500 r/min (thermal) and limiting speed 7,500 r/min (mechanical), catalogue mass 630 g. Selection figures for 3209 ATN9: the static-to-dynamic ratio C0/C is 0.76, Pu 1.63 kN is about 3 % of C, and catalogue mass works out to roughly 14 g per millimetre of bore. At the printed limiting speed of 7,500 r/min the mean pitch diameter dm ≈ 65.0 mm implies a dn value around 488k mm·r/min; the 8,500 r/min reference speed is the thermal-planning figure under catalogue load. Bore-to-OD planning: OD 85 over bore 45 is a 1.89× step for this size, and the 30.2 mm width gives a bore/width ratio of 1.49; use these ratios when housing space around the 45 mm shaft is the first constraint.
Typical equipment & failure modes
Common applications
- centrifugal pump shafts
- elevator and hoist machinery
- printing and converting machinery
Known failure patterns
- tilted mounting that loads one double row more heavily than the other
- false brinelling on the loaded row while the shaft stands idle under vibration
- TN9 cage embrittlement in a hot gearbox position beyond the 120 °C polymer ceiling
- brinelling from pressing the ring home through the balls or from static overload
- edge loading from shaft deflection or housing misalignment
Selection pitfalls — read before you substitute
- The double-row 3209 takes thrust in both directions by itself — that is the reason to choose it over two single-row bearings: one housing bore, one fit, built-in set geometry.
- Controlled axial clearance is the heart of the design: the A execution is produced to the standard double-row axial clearance; check residual clearance after mounting and at operating temperature.
- Catalogue ratings of 51/39 kN apply to the ATN9 execution; the D and DNRCBM two-piece-ring executions carry their own figures on their own pages.
- The double-row 3209 takes thrust in both directions by itself — that is the reason to choose it over two single-row bearings: one housing bore, one fit, built-in set geometry.
- Catalogue ratings are SKF PUB BU/P1 17000 figures for 3209 ATN9 as the double atn9 execution; the other order numbers of the 3209 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 3209-ATN9?
3209 ATN9 measures 45 mm bore × 85 mm OD × 30.2 mm width (1.772 × 3.346 × 1.189 in), mass about 630 g. SKF 17000 ratings: C 51 kN, C0 39 kN, Pu 1.63 kN, reference speed 8,500 r/min (thermal) and limiting speed 7,500 r/min (mechanical).
What does the ATN9 suffix mean?
A on a double-row bearing means no filling slots, so both rows carry their full ball complement in both directions. glass-fibre reinforced PA66 cage, ball-centred (suffix TN9), with a 120 °C continuous-temperature ceiling.
Which fits should I use?
With a rotating inner ring use roughly k5 on the 45 mm shaft and H7 in the 85 mm housing; check the wide ring seats square because the 30.2 mm width is sensitive to tilt.
Why choose the double-row 3209 instead of two single-row bearings?
The double-row bearing locates the shaft in both axial directions in one unit, in one housing bore and with factory-controlled axial clearance — a more compact arrangement than a pair, with no field matching of ground faces. A single-row pair offers adjustable preload instead.
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.