2306-K bearing: complete specifications & equivalents
The 2306-K is a ISO 15 radial bearing sized 30 x 72 x 27 mm (bore x OD x width). 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 | 27 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | polymer (PA66 glass-fibre reinforced) |
| Basic dynamic load rating C | 31.2 kN |
| Basic static load rating C0 | 8.8 kN |
| Fatigue load limit Pu | 0.45 kN |
| Reference speed (thermal) | 18000 rpm |
| Limiting speed (mechanical) | 13000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 500 g |
| Manufacturer designation | 2306 K |
| 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 & 2300-series range
| Bore d | 1.181 in |
|---|---|
| Outer diameter D | 2.835 in |
| Width B | 1.063 in |
| ISO bore code | 06 |
| Radial section height (D−d)/2 | 21 mm |
| Smallest bore in 2300-series | 10 mm |
| Largest outer diameter in 2300-series | 215 mm |
| Width range across 2300-series | 17–73 mm |
| Bore position in 2300-series (smallest first) | 7 of 21 |
| Bore above smallest 2300-series size | 20 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 2306 | 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. |
| 2306-E-2RS1TN9 | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 30×72×27 mm envelope, but catalogue C/C0 differ between executions (31.2/8.8 kN vs 22.5/6.8 kN) — boundary dimensions match, not a load-rating equivalent. |
| 2306-E-2RS1KTN9 | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 30×72×27 mm envelope, but catalogue C/C0 differ between executions (31.2/8.8 kN vs 22.5/6.8 kN) — boundary dimensions match, not a load-rating equivalent. |
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 2306-K model number is decoded
The 23xx series is the wide medium-section self-aligning ball bearing (ISO dimension series 23). the last two digits encode the bore: 2306 carries code 06 = 30 mm (code × 5). Envelope 30×72×27 mm (1.181×2.835×1.063 in) with a 21.0 mm radial section height, C 31.2 kN, C0 8.8 kN and Pu 0.45 kN. The open 2306 K carries no shields or seals and relies on application lubrication and external sealing. The 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 18000 r/min, limiting speed 13000 r/min, catalogue mass 500 g.
Typical equipment & failure modes
Common applications
- textile spindles and looms
- fan and blower shafts
- woodworking machine spindles
- light gearbox layshafts
Known failure patterns
- contamination wear when the open arrangement is used without adequate external sealing
- lubricant starvation where no regreasing interval is maintained
- adapter-sleeve fretting when the sleeve is not locked against the shaft shoulder
- incorrect sleeve tightening that leaves the tapered bore loose or over-expanded, changing internal clearance
- brinelling from static overload or hammer blows during mounting
- false brinelling from vibration while the shaft stands idle
Selection pitfalls — read before you substitute
- The spherical outer raceway lets 2306-K tolerate shaft deflection, but it does not increase thrust capacity — combined loads still need an angular-contact or deep-groove bearing.
- The spherical outer raceway lets 2306-K tolerate shaft deflection, but it does not increase thrust capacity — combined loads still need an angular-contact or deep-groove bearing.
- On a sleeve-mounted 2306-K, lock the sleeve against the shaft shoulder; a loose sleeve creeps and frets both the shaft and the bore.
- The suffix on 2306-K denotes a glass-fibre-reinforced polyamide 66 cage: quiet and light at the 13000 r/min limiting speed, but it softens above roughly 120 °C — check the oil temperature in hot drives.
- The spherical outer raceway lets 2306-K tolerate shaft deflection, but it does not increase thrust capacity — combined loads still need an angular-contact or deep-groove bearing.
- Fillet radii must clear the 2306-K chamfer so the 27 mm-wide ring seats square; an oversized shaft radius creates point contact on the ring face.
Frequently asked questions
What are the dimensions of 2306-K?
SKF 2306 K measures 30 mm bore × 72 mm OD × 27 mm width (1.181 × 2.835 × 1.063 in), mass about 500 g. It is open, with no shields or seals.
How does the bore code in 2306 work?
The final two digits of 2306 are bore code 06, multiplied by 5 to give 30 mm.
What is the speed rating of 2306-K?
SKF lists a 18000 r/min thermal reference speed and a 13000 r/min mechanical limiting speed for 2306 K; real limits also depend on lubrication and fits.
How much misalignment can 2306-K tolerate?
Self-aligning ball bearings tolerate roughly 2–3° of static misalignment for open executions; sealed 2RS1 variants like 2306-K allow less (about 1°) because the seal lip binds first.
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.