C2211-KTN9-AHX311 bearing: complete specifications & equivalents
The C2211-KTN9-AHX311 is a ISO 15 radial bearing sized 50 x 100 x 25 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 | 100 mm |
| Width B | 25 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | polymer (PA66 glass-fibre reinforced) |
| Basic dynamic load rating C | 116 kN |
| Basic static load rating C0 | 114 kN |
| Fatigue load limit Pu | 13.4 kN |
| Reference speed (thermal) | 6300 rpm |
| Limiting speed (mechanical) | 9000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 950 g |
| Manufacturer designation | SKF C 2211 KTN9 + AHX 311 |
| Standard | ISO 15 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 10.2-10.3 CARB on sleeves |
| Last verified | 2026-09-29 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 10.2-10.3 CARB on sleeves) · extracted 2026-09-29
Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 10.2-10.3 CARB on sleeves); 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 & carb-withdrawal-sleeve range
| Bore d | 1.969 in |
|---|---|
| Outer diameter D | 3.937 in |
| Width B | 0.984 in |
| ISO bore code | 11 |
| Radial section height (D−d)/2 | 25 mm |
| Smallest bore in carb-withdrawal-sleeve | 35 mm |
| Largest outer diameter in carb-withdrawal-sleeve | 1580 mm |
| Width range across carb-withdrawal-sleeve | 23–462 mm |
| Bore position in carb-withdrawal-sleeve (smallest first) | 4 of 49 |
| Bore above smallest carb-withdrawal-sleeve size | 15 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| C2211 | ISO 15 | full Dimensions and internal design equivalent — standard interchange. | ISO 15 boundary-dimension envelope; brand-specific OEM equivalents (NSK/FAG/NTN) pending multi-source data. |
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 C2211-KTN9-AHX311 model number is decoded
Housing side of C2211-KTN9-AHX311 is conventional: a 100 mm H7 bore takes the CARB outer ring, which is free to slide axially in the housing — the toroidal raceway handles the misalignment and the sleeve side handles the location on the 50 mm shaft.C2211-KTN9-AHX311 is a complete SKF mounting unit for the largest CARB sizes: the toroidal roller bearing C 2211 KTN9 on withdrawal sleeve AHX 311, listed in SKF catalogue PUB BU/P1 17000 for a 50 mm shaft seat.Digit by digit, C2211-KTN9-AHX311 = CARB bearing C 2211 KTN9 (55 mm bore, 100 mm OD, 25 mm width) + withdrawal sleeve AHX 311 for the 50 mm cylindrical shaft seat; cage and tolerance letters stay with the bearing half of the designation. Combined mass of the unit — bearing C 2211 KTN9 plus sleeve AHX 311 — is about 1 kg; plan lifting gear and heating equipment around the assembly, not the bare bearing. Selection arithmetic: the unit carries the ratings of its bearing — C 116 kN, C0 114 kN, Pu 13.4 kN from the CARB table — because the sleeve adds no capacity, only the mounting interface on the 50 mm shaft. Record the sleeve travel at mounting of C2211-KTN9-AHX311: the clearance set into the 55 mm bearing today is the reference for the next re-clearance check, and travel data catches seat wear on the 50 mm shaft over the years.
Typical equipment & failure modes
Common applications
- paper machine drying cylinders and calender rolls with long, thermally expanding shafts
- continuous-caster guide rolls and slab-caster segments under heat growth
- vibrating screen exciters fitted with the VE240 tolerance execution
- heavy industrial gearbox layshafts used as the non-locating position
Known failure patterns
- sleeve creep on the shaft seat when the sleeve was not driven to its marked travel or clearance
- raceway spalling of the CARB bearing after the catalogue L10 life under contaminated lubrication
- sleeve creep on the shaft seat when the sleeve was not driven to its marked travel or clearance
- misalignment edge loading when the housing bore is out of square with the shaft seat
- raceway spalling of the CARB bearing after the catalogue L10 life under contaminated lubrication
Selection pitfalls — read before you substitute
- Protect the 50 mm seat: sleeve bore corrosion or seat ovality shows up later as sleeve creep and fretting; inspect and measure the seat at every dismounting of C2211-KTN9-AHX311.
- Do not re-use a sleeve that shows taper scuffing: a scratched cone changes the travel-to-clearance relationship of the whole C2211-KTN9-AHX311 unit — replace the sleeve with the bearing.
- Sleeve and bearing are a matched taper pair: never fit sleeve AHX 311 onto a different CARB bearing of the same bore size without verifying the execution letters — seat length and taper contact differ.
- The 116/114 kN ratings are SKF catalogue 17000 values for the CARB bearing; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.
- Quote the full unit designation SKF C 2211 KTN9 + AHX 311 when purchasing — bearing and sleeve execution letters are part of the order number and define the matched taper pair.
Frequently asked questions
What are the dimensions and catalogue data of C2211-KTN9-AHX311?
The unit is CARB bearing C 2211 KTN9 on withdrawal sleeve AHX 311, fitting a 50 mm shaft (1.969 in), housing bore 100 mm, bearing width 25 mm. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 116 kN, C0 114 kN, fatigue load limit Pu 13.4 kN, combined mass about 0.9 kg. Reference speed 6,300 r/min, limiting speed 9,000 r/min (bearing values).
Why does C2211-KTN9-AHX311 list a 50 mm shaft size when the bearing bore is 55 mm?
The sleeve takes up the difference: the withdrawal sleeve AHX 311 has a tapered outside that engages the bearing's 55 mm tapered bore and a cylindrical bore that seats on the 50 mm shaft. The catalogue's principal dimensions describe the mounted result — shaft seat, housing bore and bearing width — not the bearing bore alone.
Is C2211-KTN9-AHX311 a locating or non-locating bearing?
Non-locating. The CARB toroidal roller bearing is designed as the free end of the shaft: its raceway geometry tolerates misalignment and allows axial float, while a separate locating bearing (typically a spherical roller or paired taper) takes the thrust. The sleeve does not change this function.
Can I buy the bearing C 2211 KTN9 and the sleeve AHX 311 separately?
The components are catalogued separately, but the taper pair is matched — the sleeve seat and the bearing bore are manufactured to the same execution. Ordering the unit C2211-KTN9-AHX311 as one catalogue line keeps bearing and sleeve compatible; if ordering separately, quote both full designations including execution letters.
How is the clearance of C2211-KTN9-AHX311 set at mounting?
By sleeve travel: the withdrawal sleeve AHX 311 is driven or pressed to a marked travel on the 50 mm seat, which sets the interference into the 55 mm bore and with it the radial clearance. Record the travel; hydraulic assistance is standard at this size.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 10.2-10.3 CARB on sleeves on 2026-09-29. Read our editorial & correction policy.