1210-EKTN9 bearing: complete specifications & equivalents
The 1210-EKTN9 is a ISO 15 radial bearing sized 50 x 90 x 20 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 50 mm |
| Outer diameter D | 90 mm |
| Width B | 20 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | polymer (PA66 glass-fibre reinforced) |
| Basic dynamic load rating C | 26.5 kN |
| Basic static load rating C0 | 9.15 kN |
| Fatigue load limit Pu | 0.48 kN |
| Reference speed (thermal) | 16000 rpm |
| Limiting speed (mechanical) | 10000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 530 g |
| Manufacturer designation | 1210 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 | 1.969 in |
|---|---|
| Outer diameter D | 3.543 in |
| Width B | 0.787 in |
| ISO bore code | 10 |
| 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) | 15 of 32 |
| Bore above smallest 1200-series size | 44 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 1210 | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 50×90×20 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting. |
| 1210-ETN9 | SKF | full Dimensions and internal design equivalent — standard interchange. | Same 50×90×20 mm envelope with catalogue ratings within 10 %; 1210 ETN9 is the glass-fibre PA66 cage, open arrangement execution of this size — boundary dimensions interchangeable, only the seal/cage/bore execution differs. |
| 11210-TN9 | SKF | full Dimensions and internal design equivalent — standard interchange. | Same 50×90×20 mm envelope with catalogue ratings within 10 %; 11210 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 1210-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: 1210 carries code 10 = 50 mm (code × 5). Envelope 50×90×20 mm (1.969×3.543×0.787 in) with a 20.0 mm radial section height, C 26.5 kN, C0 9.15 kN and Pu 0.48 kN. The open 1210 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 16000 r/min, limiting speed 10000 r/min, catalogue mass 530 g.
Typical equipment & failure modes
Common applications
- industrial electric motors
- conveyor drum and pulley shafts
- agricultural gearboxes
- textile machinery drives
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
- rolling-contact fatigue spalling once the catalogue L10 life is exceeded
- brinelling from static overload or hammer blows during mounting
Selection pitfalls — read before you substitute
- At 50 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.
- Mount 1210-EKTN9 by heating the inner ring (max 120 °C) on a cylindrical bore — driving it home through the outer ring or balls brinells the raceways.
- Tighten the adapter sleeve to the SKF-recommended starting clearance, not to feel — an over-tightened sleeve expands the inner ring and removes all internal clearance.
- The EKTN9 suffix on 1210-EKTN9 denotes a glass-fibre-reinforced polyamide 66 cage: quiet and light at the 10000 r/min limiting speed, but it softens above roughly 120 °C — check the oil temperature in hot drives.
- Fillet radii must clear the 1210-EKTN9 chamfer so the 20 mm-wide ring seats square; an oversized shaft radius creates point contact on the ring face.
- Self-aligning ball bearings tolerate up to roughly 2–3° of static misalignment, but the sealed 1210-EKTN9 (2RS1) allows less — the lip seal binds before the spherical raceway does.
Frequently asked questions
What are the dimensions of 1210-EKTN9?
SKF 1210 EKTN9 measures 50 mm bore × 90 mm OD × 20 mm width (1.969 × 3.543 × 0.787 in), mass about 530 g. It is open, with no shields or seals.
How does the bore code in 1210 work?
The final two digits of 1210 are bore code 10, multiplied by 5 to give 50 mm.
What load can 1210-EKTN9 take?
Catalogue values for 1210 EKTN9: dynamic C 26.5 kN, static C0 9.15 kN, fatigue limit Pu 0.48 kN. Use C in life calculation and C0 for static checks at 50 mm bore.
What is the speed rating of 1210-EKTN9?
SKF lists a 16000 r/min thermal reference speed and a 10000 r/min mechanical limiting speed for 1210 EKTN9; real limits also depend on lubrication and fits.
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.