C3040-K bearing: complete specifications & equivalents
The C3040-K is a ISO 15 radial bearing sized 200 x 310 x 82 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 200 mm |
| Outer diameter D | 310 mm |
| Width B | 82 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 1120 kN |
| Basic static load rating C0 | 1730 kN |
| Fatigue load limit Pu | 153 kN |
| Reference speed (thermal) | 1700 rpm |
| Limiting speed (mechanical) | 2400 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 22500 g |
| Manufacturer designation | C 3040 K |
| 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 | 7.874 in |
|---|---|
| Outer diameter D | 12.205 in |
| Width B | 3.228 in |
| ISO bore code | 40 |
| Radial section height (D−d)/2 | 55 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) | 6 of 33 |
| Bore above smallest C3000-series size | 80 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| C3040 | SKF | full Dimensions and internal design equivalent — standard interchange. | Same 200×310×82 mm ISO 15 envelope and equivalent catalogue C/C0; C 3040 is the cylindrical-bore steel-caged execution of this size — boundary dimensions interchangeable, only mounting and cage execution differ. |
| 23040 | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 200×310×82 mm envelope as the SKF spherical roller bearing SKF 23040 CC/W33, but catalogue C/C0 differ (1120/1730 kN vs 1058/1530 kN) — and the functions differ: spherical locates axially, CARB floats. Pair them; never swap one-for-one. |
| 23040-CCK-W33 | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 200×310×82 mm envelope as the SKF spherical roller bearing SKF 23040 CCK/W33, but catalogue C/C0 differ (1120/1730 kN vs 1058/1530 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 C3040-K model number is decoded
In SKF catalogue PUB BU/P1 17000, C 3040 K denotes a toroidal roller bearing whose 82 mm long rollers crown at both ends: the contact accepts angular misalignment while the ring positions float, which is why CARB bearings are specified at the free shaft end. In C 3040 K the 30 dimension series fixes the 310 mm OD and 82 mm width around the 200 mm bore (code 40 × 5); the suffix K then selects the tapered 1:12 bore for adapter (H) sleeve mounting, pressed steel cage. The K suffix gives a 1:12 tapered 200 mm bore, mounted on an adapter (H) sleeve so the bearing can be driven up to the specified clearance. The same size is listed in both bore executions, and the boundary dimensions 200×310×82 mm are identical — only the mounting method changes. Speed planning separates the 1,700 r/min thermal reference from the 2,400 r/min mechanical limiting speed. The full-complement V executions carry more load but list no thermal reference speed; the steel-caged executions run faster and cooler at light load. After fitting, confirm the inner ring can be pushed axially by hand through the catalogue displacement range; a ring that will not slide means the position is locked and will preload in service.
Typical equipment & failure modes
Common applications
- continuous-caster guide rolls and slab-caster segments under heat growth
- vibrating screen exciters fitted with the VE240 tolerance execution
- long fan and kiln main shafts where the free end must float without thrust load
- heavy industrial gearbox layshafts used as the non-locating position
Known failure patterns
- raceway spalling once the catalogue L10 life is exceeded or after sustained overload
- 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
- hard-particle indentation where oil or grease filtration is inadequate
- grease churning and overheating when a high-speed thrust position is over-packed
Selection pitfalls — read before you substitute
- At 200 mm bore, shaft expansion is already measurable: calculate the required float inside the 82 mm wide bearing rather than assuming the free-end clearance is "enough" at operating temperature.
- Never use C 3040 K 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.
- Tapered-bore K executions mount on adapter sleeves (1:12) and K30 on withdrawal sleeves (1:30) — the 200 mm bore changes the sleeve family, and the drive-up procedure differs accordingly.
- 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 3040 K must float; the two are designed to be used as a pair.
- The 1120/1730 kN ratings and 22500 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 is the difference between V and TN9 CARB executions?
V is the full-complement execution with no cage — more rollers, higher C (1120 kN here) but a lower speed ceiling and no thermal reference speed. TN9 is the glass-fibre PA66 caged execution, faster and quieter at somewhat lower load. C 3040 K is the tapered 1:12 bore for adapter (H) sleeve mounting, pressed steel cage.
How is C 3040 K mounted?
The tapered 1:12 bore mounts on an adapter (H) sleeve with a defined drive-up; heat the bearing to max 120 °C when fitting, support full ring faces, and verify axial float afterwards.
What are the dimensions and ratings of the C 3040 K?
A C 3040 K measures 200 mm bore × 310 mm outside diameter × 82 mm width (7.874 × 12.205 × 3.228 in). From SKF catalogue PUB BU/P1 17000: dynamic C 1120 kN, static C0 1730 kN, fatigue limit Pu 153 kN, reference speed 1,700 r/min, limiting speed 2,400 r/min, mass about 22500 g.
Can a CARB bearing like C 3040 K locate the shaft axially?
No — that is the defining feature. C 3040 K deliberately allows the inner ring to float axially inside the outer ring while the toroidal rollers self-align. It must be paired with a separate locating bearing (spherical, tapered or angular contact) that takes 100 % of the thrust.
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.