C3076-KM bearing: complete specifications & equivalents
The C3076-KM is a ISO 15 radial bearing sized 380 x 560 x 135 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 380 mm |
| Outer diameter D | 560 mm |
| Width B | 135 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 3000 kN |
| Basic static load rating C0 | 5200 kN |
| Fatigue load limit Pu | 380 kN |
| Reference speed (thermal) | 900 rpm |
| Limiting speed (mechanical) | 1200 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 110000 g |
| Manufacturer designation | C 3076 KM |
| 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 | 14.961 in |
|---|---|
| Outer diameter D | 22.047 in |
| Width B | 5.315 in |
| ISO bore code | 76 |
| Radial section height (D−d)/2 | 90 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) | 15 of 33 |
| Bore above smallest C3000-series size | 260 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| C3076-M | SKF | full Dimensions and internal design equivalent — standard interchange. | Same 380×560×135 mm ISO 15 envelope and equivalent catalogue C/C0; C 3076 M is the cylindrical-bore M brass-caged execution of this size — boundary dimensions interchangeable, only mounting and cage execution differ. |
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 C3076-KM model number is decoded
In SKF catalogue PUB BU/P1 17000, C 3076 KM denotes a toroidal roller bearing whose 135 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. SKF builds the CARB order number from size plus execution: the bare number C 3076 is the brass-caged cylindrical-bore bearing, K (or K30) makes the bore tapered for sleeve mounting, and the cage/seal letters follow — here KM. The K suffix gives a 1:12 tapered 380 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 380×560×135 mm are identical — only the mounting method changes. Pairing rule: use the CARB bearing opposite one locating spherical or tapered bearing — never at both shaft ends — and check the locating bearing takes 100 % of the thrust, since C 3076 KM deliberately carries none. 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
- 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
- brinelling of washer raceways from impact or mounting force applied through the rolling elements
- oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips
Selection pitfalls — read before you substitute
- Above 200 mm bore these bearings weigh tens of kilograms (110 kg here) — lifting gear and induction heating are mandatory, and a cocked ring scores the toroidal raceway before start-up.
- The quoted 3000/5200 kN ratings belong to this exact execution (C 3076 KM); 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 3076 KM must float; the two are designed to be used as a pair.
- Never use C 3076 KM 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 3000/5200 kN ratings and 110000 g mass are SKF catalogue values transcribed from ch. 10.1 of PUB BU/P1 17000 (PDF table page 866); 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 3076 KM have?
A C 3076 KM measures 380 mm bore × 560 mm outside diameter × 135 mm width (14.961 × 22.047 × 5.315 in). From SKF catalogue PUB BU/P1 17000: dynamic C 3000 kN, static C0 5200 kN, fatigue limit Pu 380 kN, reference speed 900 r/min, limiting speed 1,200 r/min, mass about 110000 g.
What does C 3076 KM mean in SKF part numbering?
C marks CARB; 30 the dimension series; the size code gives 380 mm bore; KM is the execution (tapered 1:12 bore for adapter (H) sleeve mounting, machined brass M cage). The envelope follows ISO 15 and matches spherical roller bearing outlines, but the functions differ.
Why is C 3076 KM 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.