3203-ATN9 bearing: complete specifications & equivalents
The 3203-ATN9 is a ISO 15 radial bearing sized 17 x 40 x 17.5 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 17 mm |
| Outer diameter D | 40 mm |
| Width B | 17.5 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | polymer (PA66 glass-fibre reinforced) |
| Basic dynamic load rating C | 14.3 kN |
| Basic static load rating C0 | 8.8 kN |
| Fatigue load limit Pu | 0.365 kN |
| Reference speed (thermal) | 19000 rpm |
| Limiting speed (mechanical) | 16000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 96 g |
| Manufacturer designation | 3203 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 | 0.669 in |
|---|---|
| Outer diameter D | 1.575 in |
| Width B | 0.689 in |
| ISO bore code | 03 |
| Radial section height (D−d)/2 | 11.5 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) | 4 of 22 |
| Bore above smallest 3200-series size | 7 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 3203-A-2Z | SKF | full Dimensions and internal design equivalent — standard interchange. | Same 17×40×17.5 mm envelope with catalogue ratings within 10 %; 3203 A-2Z is the stamped steel cage, shields (-2Z) execution of this size — boundary dimensions interchangeable, execution differs. |
| 3203-A-2RS1 | SKF | full Dimensions and internal design equivalent — standard interchange. | Same 17×40×17.5 mm envelope with catalogue ratings within 10 %; 3203 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 3203-ATN9 model number is decoded
3203 ATN9 is SKF's 17 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, 17×40×17.5 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 17×40×17.5 mm (0.669×1.575×0.689 in), 11.5 mm radial section height, C 14.3 kN, C0 8.8 kN, Pu 0.365 kN.reference speed 19,000 r/min (thermal) and limiting speed 16,000 r/min (mechanical), catalogue mass 96 g. Speed planning distinguishes the two published ceilings mechanically: the cage and balls tolerate 16,000 r/min while thermal balance under catalogue load sets the 19,000 r/min reference; at dm ≈ 28.5 mm the corresponding dn is approximately 456k mm·r/min. Selection figures for 3203 ATN9: the static-to-dynamic ratio C0/C is 0.62, Pu 0.365 kN is about 3 % of C, and catalogue mass works out to roughly 6 g per millimetre of bore. Speed-ratio note for this exact unit: the reference speed is 19,000 r/min against a 16,000 r/min limiting speed, i.e. a reference-to-limit ratio of 1.19.
Typical equipment & failure modes
Common applications
- small two-bearing-housing arrangements
- small double-supported gear shafts needing two-direction location in one bearing
- compact pump and compressor drives
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
- mounting score marks when the bearing is cocked over a burr or keyway
- brinelling from pressing the ring home through the balls or from static overload
Selection pitfalls — read before you substitute
- The double-row 3203 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 of 14.3/8.8 kN apply to the ATN9 execution; the D and DNRCBM two-piece-ring executions carry their own figures on their own pages.
- 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.
- Compared with a single-row pair of the same bore, the double-row 3203 occupies less axial space but offers less freedom to adjust preload — do not substitute without re-checking the arrangement.
- Catalogue ratings are SKF PUB BU/P1 17000 figures for 3203 ATN9 as the double atn9 execution; the other order numbers of the 3203 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 3203-ATN9?
3203 ATN9 measures 17 mm bore × 40 mm OD × 17.5 mm width (0.669 × 1.575 × 0.689 in), mass about 96 g. SKF 17000 ratings: C 14.3 kN, C0 8.8 kN, Pu 0.365 kN, reference speed 19,000 r/min (thermal) and limiting speed 16,000 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.
What does the D mean in ATN9?
D marks a two-piece inner ring, used on the heavy 33-series executions to simplify mounting; the rest of the suffix identifies the cage (MA brass outer-ring-centred, M brass ball-centred, J1 stamped steel, TN9 PA66) and snap-ring/clearance options (NR, CB).
Does the 3203 double-row bearing need pairing?
No — both ball rows are built into one bearing, so bidirectional location does not require a second unit. Controlled axial clearance is part of the design rather than a field adjustment.
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.