C3052 bearing: complete specifications & equivalents
The C3052 is a ISO 15 radial bearing sized 260 x 400 x 104 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 260 mm |
| Outer diameter D | 400 mm |
| Width B | 104 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 1760 kN |
| Basic static load rating C0 | 2850 kN |
| Fatigue load limit Pu | 232 kN |
| Reference speed (thermal) | 1300 rpm |
| Limiting speed (mechanical) | 1800 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 47000 g |
| Manufacturer designation | C 3052 |
| Standard | ISO 15 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 10.1 CARB toroidal roller bearings |
| Last verified | 2026-09-27 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 10.1 CARB toroidal roller bearings) · extracted 2026-09-27
Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 10.1 CARB toroidal roller bearings); 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 & C3000-series range
| Bore d | 10.236 in |
|---|---|
| Outer diameter D | 15.748 in |
| Width B | 4.094 in |
| ISO bore code | 52 |
| Radial section height (D−d)/2 | 70 mm |
| Smallest bore in C3000-series | 120 mm |
| Largest outer diameter in C3000-series | 1420 mm |
| Width range across C3000-series | 46–308 mm |
| Bore position in C3000-series (smallest first) | 9 of 33 |
| Bore above smallest C3000-series size | 140 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| C3052-K | SKF | full Dimensions and internal design equivalent — standard interchange. | Same 260×400×104 mm ISO 15 envelope and equivalent catalogue C/C0; C 3052 K is the 1:12 tapered-bore K steel-caged execution of this size — boundary dimensions interchangeable, only mounting and cage execution differ. |
| 23052 | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 260×400×104 mm envelope as the SKF spherical roller bearing SKF 23052 CC/W33, but catalogue C/C0 differ (1760/2850 kN vs 1675/2550 kN) — and the functions differ: spherical locates axially, CARB floats. Pair them; never swap one-for-one. |
| 23052-CCK-W33 | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 260×400×104 mm envelope as the SKF spherical roller bearing SKF 23052 CCK/W33, but catalogue C/C0 differ (1760/2850 kN vs 1675/2550 kN) — and the functions differ: spherical locates axially, CARB floats. Pair them; never swap one-for-one. |
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 C3052 model number is decoded
The CARB bearing C 3052 combines the self-aligning behaviour of a spherical roller bearing with the axial freedom of a cylindrical bearing in one 260 mm bore, 400 mm outside diameter, 104 mm wide unit rated 1760 kN dynamic. SKF builds the CARB order number from size plus execution: the bare number C 3052 is the steel-caged cylindrical-bore bearing, K (or K30) makes the bore tapered for sleeve mounting, and the cage/seal letters follow — here the bare number. The cylindrical 260 mm bore mounts directly on a machined seat; the outer ring takes a loose housing fit so the bearing can float axially. The same size is listed in both bore executions, and the boundary dimensions 260×400×104 mm are identical — only the mounting method changes. The 47000 g mass over the 260×400×104 mm envelope yields about 6.77 kN dynamic per millimetre of bore — the long toroidal rollers give this family its radial capacity density. Open executions accept relubrication — route it through the outer-ring groove on sizes that have one and purge stale grease at service intervals. Grease through the annular groove features where provided; on open executions feed lubricant past the long roller set at assembly, since the 104 mm wide cavity does not fill itself.
Typical equipment & failure modes
Common applications
- heavy industrial gearbox layshafts used as the non-locating position
- winder and reel drums in paper and steel strip plants
- paper machine drying cylinders and calender rolls with long, thermally expanding shafts
- continuous-caster guide rolls and slab-caster segments under heat growth
Known failure patterns
- roller-end and flange smearing after lubricant starvation at the long roller contacts
- thermal preloading when a shaft is located at both ends and growth has nowhere to go
- brass cage pocket wear under marginal lubrication in the large-bore M/MB executions
- condensation pitting in machines that run intermittently in humid environments
- abrasive paste forming as dust bypasses the housing seals into the open washer set
Selection pitfalls — read before you substitute
- Above 200 mm bore these bearings weigh tens of kilograms (47 kg here) — lifting gear and induction heating are mandatory, and a cocked ring scores the toroidal raceway before start-up.
- The quoted 1760/2850 kN ratings belong to this exact execution (C 3052); VE240 vibrating-screen variants and sealed 2CS/2NS variants have their own figures even at the same envelope.
- Do not block the axial displacement in the drawing: housing covers, labyrinth rings and snap rings must leave the catalogue float (s) free, or the bearing silently becomes a poorly located fixed bearing.
- Envelope-identical spherical roller bearings (same ISO 15 d×D×B) are not drop-in equivalents — they locate the shaft axially, while C 3052 must float; the two are designed to be used as a pair.
- Never use C 3052 as the locating bearing: it carries no axial load by design — the arrangement needs a separate locating spherical, tapered or angular bearing facing the thrust.
- The 1760/2850 kN ratings and 47000 g mass are SKF catalogue values transcribed from ch. 10.1 of PUB BU/P1 17000 (PDF table page 864); mounting data — axial displacement (s) and seating details — appears in the running text because the structured record carries the boundary envelope only.
Frequently asked questions
What fails first on a misapplied CARB bearing?
Blocking the designed axial float — clamping the free end or locating both shaft ends — turns thermal growth into edge loading and spalls the toroidal raceways. Cage damage and ordinary fatigue follow overload or dry running.
Which dimensions does the C 3052 have?
A C 3052 measures 260 mm bore × 400 mm outside diameter × 104 mm width (10.236 × 15.748 × 4.094 in). From SKF catalogue PUB BU/P1 17000: dynamic C 1760 kN, static C0 2850 kN, fatigue limit Pu 232 kN, reference speed 1,300 r/min, limiting speed 1,800 r/min, mass about 47000 g.
What does C 3052 mean in SKF part numbering?
C marks CARB; 30 the dimension series; the size code gives 260 mm bore; the bare number is the execution (cylindrical bore for direct shaft fitting, pressed steel cage). The envelope follows ISO 15 and matches spherical roller bearing outlines, but the functions differ.
Why is C 3052 used opposite a spherical roller bearing?
The spherical bearing locates the shaft and takes thrust; the CARB bearing at the other end self-aligns but floats, absorbing thermal expansion without inducing axial load. The pair is standard on paper machine drying cylinders and long caster rolls.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 10.1 CARB toroidal roller bearings on 2026-09-27. Read our editorial & correction policy.