1209-EKTN9 bearing: complete specifications & equivalents
The 1209-EKTN9 is a ISO 15 radial bearing sized 45 x 85 x 19 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 | 19 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | polymer (PA66 glass-fibre reinforced) |
| Basic dynamic load rating C | 22.9 kN |
| Basic static load rating C0 | 7.8 kN |
| Fatigue load limit Pu | 0.4 kN |
| Reference speed (thermal) | 17000 rpm |
| Limiting speed (mechanical) | 11000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 470 g |
| Manufacturer designation | 1209 EKTN9 |
| 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 & 1200-series range
| Bore d | 1.772 in |
|---|---|
| Outer diameter D | 3.346 in |
| Width B | 0.748 in |
| ISO bore code | 09 |
| Radial section height (D−d)/2 | 20 mm |
| Smallest bore in 1200-series | 6 mm |
| Largest outer diameter in 1200-series | 230 mm |
| Width range across 1200-series | 6–154 mm |
| Bore position in 1200-series (smallest first) | 14 of 32 |
| Bore above smallest 1200-series size | 39 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 1209 | 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. |
| 1209-ETN9 | SKF | full Dimensions and internal design equivalent — standard interchange. | Same 45×85×19 mm envelope with catalogue ratings within 10 %; 1209 ETN9 is the glass-fibre PA66 cage, open arrangement execution of this size — boundary dimensions interchangeable, only the seal/cage/bore execution differs. |
| 11209-TN9 | SKF | full Dimensions and internal design equivalent — standard interchange. | Same 45×85×19 mm envelope with catalogue ratings within 10 %; 11209 TN9 is the glass-fibre PA66 cage, open arrangement execution of this size — boundary dimensions interchangeable, only the seal/cage/bore 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 1209-EKTN9 model number is decoded
The 12xx series is the light/normal-section self-aligning ball bearing (ISO dimension series 02). the last two digits encode the bore: 1209 carries code 09 = 45 mm (code × 5). Envelope 45×85×19 mm (1.772×3.346×0.748 in) with a 20.0 mm radial section height, C 22.9 kN, C0 7.8 kN and Pu 0.4 kN. The open 1209 EKTN9 carries no shields or seals and relies on application lubrication and external sealing. The EKTN9 suffix identifies the glass-fibre-reinforced polyamide 66 cage execution. The K suffix marks a 1:12 tapered bore for direct mounting on a tapered shaft or with an adapter sleeve. Reference (thermal) speed 17000 r/min, limiting speed 11000 r/min, catalogue mass 470 g.
Typical equipment & failure modes
Common applications
- pump shafts with mild misalignment
- material-handling equipment
- industrial electric motors
- conveyor drum and pulley shafts
Known failure patterns
- lubricant starvation where no regreasing interval is maintained
- contamination wear when the open arrangement is used without adequate external sealing
- incorrect sleeve tightening that leaves the tapered bore loose or over-expanded, changing internal clearance
- adapter-sleeve fretting when the sleeve is not locked against the shaft shoulder
- false brinelling from vibration while the shaft stands idle
- fretting corrosion on a creeping shaft or housing seat
Selection pitfalls — read before you substitute
- Fillet radii must clear the 1209-EKTN9 chamfer so the 19 mm-wide ring seats square; an oversized shaft radius creates point contact on the ring face.
- Assign interference to the rotating ring: on a 45 mm rotating shaft use a k5 seat with an H7 housing; reverse the logic if the outer ring rotates.
- The K suffix means a 1:12 tapered bore: 1209-EKTN9 is not a drop-in for the straight-bore version — it needs a tapered shaft or an H-series adapter sleeve.
- The EKTN9 suffix on 1209-EKTN9 denotes a glass-fibre-reinforced polyamide 66 cage: quiet and light at the 11000 r/min limiting speed, but it softens above roughly 120 °C — check the oil temperature in hot drives.
- At 45 mm bore, C3 clearance is the safe choice when interference fits plus temperature rise consume the CN clearance; a hot tight bearing with no residual clearance fails fast.
- The spherical outer raceway lets 1209-EKTN9 tolerate shaft deflection, but it does not increase thrust capacity — combined loads still need an angular-contact or deep-groove bearing.
Frequently asked questions
What are the dimensions of 1209-EKTN9?
SKF 1209 EKTN9 measures 45 mm bore × 85 mm OD × 19 mm width (1.772 × 3.346 × 0.748 in), mass about 470 g. It is open, with no shields or seals.
How does the bore code in 1209 work?
The final two digits of 1209 are bore code 09, multiplied by 5 to give 45 mm.
How much misalignment can 1209-EKTN9 tolerate?
Self-aligning ball bearings tolerate roughly 2–3° of static misalignment for open executions; sealed 2RS1 variants like 1209-EKTN9 allow less (about 1°) because the seal lip binds first.
Can 1209-EKTN9 take axial load?
A self-aligning ball bearing can carry some axial load in addition to radial load, but its axial capacity is lower than an angular-contact bearing of the same envelope. Use it where misalignment, not thrust, is the main requirement.
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.