C3030-MB bearing: complete specifications & equivalents
The C3030-MB is a ISO 15 radial bearing sized 150 x 225 x 56 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 150 mm |
| Outer diameter D | 225 mm |
| Width B | 56 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 540 kN |
| Basic static load rating C0 | 850 kN |
| Fatigue load limit Pu | 81.5 kN |
| Reference speed (thermal) | 2400 rpm |
| Limiting speed (mechanical) | 3200 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 8450 g |
| Manufacturer designation | C 3030 MB |
| 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 | 5.906 in |
|---|---|
| Outer diameter D | 8.858 in |
| Width B | 2.205 in |
| ISO bore code | 30 |
| Radial section height (D−d)/2 | 37.5 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) | 2 of 33 |
| Bore above smallest C3000-series size | 30 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| C3030-V | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 150×225×56 mm envelope, but catalogue C/C0 differ between the cylindrical-bore MB inner-ring-guided brass-caged and cylindrical-bore full-complement V executions (540/850 kN vs 585/960 kN) — envelope match, not a load-rating equivalent. |
| C3030-KV | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 150×225×56 mm envelope, but catalogue C/C0 differ between the cylindrical-bore MB inner-ring-guided brass-caged and 1:12 tapered-bore K full-complement V executions (540/850 kN vs 585/960 kN) — envelope match, not a load-rating equivalent. |
| 23030 | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 150×225×56 mm envelope as the SKF spherical roller bearing SKF 23030 CC/W33, but catalogue C/C0 differ (540/850 kN vs 531/750 kN) — and the functions differ: spherical locates axially, CARB floats. Pair them; never swap one-for-one. |
| 23030-CCK-W33 | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 150×225×56 mm envelope as the SKF spherical roller bearing SKF 23030 CCK/W33, but catalogue C/C0 differ (540/850 kN vs 531/750 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 C3030-MB model number is decoded
C 3030 MB is a CARB toroidal roller bearing to ISO 15: a single row of long, symmetrical barrel-shaped rollers between guide flanges, sized 150×225×56 mm, as listed in SKF catalogue PUB BU/P1 17000 ch. 10.1. Reading the code: C marks the CARB toroidal family, the first two digits (30) identify the ISO dimension series and the last two (30) encode the 150 mm bore; suffixes describe bore and execution. CARB bearings locate neither radially nor axially: the inner ring can walk axially inside the outer ring over the catalogue-listed axial-displacement range (s), so shaft thermal growth disappears as thrust rather than preloading the 150 mm seat. Selection arithmetic: C 540 kN against C0 850 kN gives a C0/C ratio of 1.57, and the 81.5 kN fatigue load limit Pu sets the contamination-adjusted life floor. Mounting: slide the bearing onto the 150 mm seat or heat it (max 120 °C) and seat it square; never press through the 56 mm roller set, and leave the free-end housing shoulder clear so axial float is unrestricted.
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
- roller-end and flange smearing after lubricant starvation at the long roller contacts
- edge loading and premature spalling when the CARB position is blocked from its designed axial float
- PA66 cage (TN9) softening when the sustained temperature passes the polymer limit
- rolling-contact fatigue spalling after the catalogue L10 life is exhausted
- oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips
Selection pitfalls — read before you substitute
- At 150 mm bore, shaft expansion is already measurable: calculate the required float inside the 56 mm wide bearing rather than assuming the free-end clearance is "enough" at operating temperature.
- Tapered-bore K executions mount on adapter sleeves (1:12) and K30 on withdrawal sleeves (1:30) — the 150 mm bore changes the sleeve family, and the drive-up procedure differs accordingly.
- Reference and limiting speeds are different limits: the 2,400 r/min reference speed is the thermal criterion under load, the limiting value is the mechanical ceiling; observe the reference under load unless the arrangement calculation says otherwise.
- The quoted 540/850 kN ratings belong to this exact execution (C 3030 MB); 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.
- The 540/850 kN ratings and 8450 g mass are SKF catalogue values transcribed from ch. 10.1 of PUB BU/P1 17000 (PDF table page 862); 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
Why is C 3030 MB 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.
Is the C 3030 MB sealed?
No, it is an open execution relying on the housing seals; relubrication follows the groove/hole features of the size.
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 3030 MB have?
A C 3030 MB measures 150 mm bore × 225 mm outside diameter × 56 mm width (5.906 × 8.858 × 2.205 in). From SKF catalogue PUB BU/P1 17000: dynamic C 540 kN, static C0 850 kN, fatigue limit Pu 81.5 kN, reference speed 2,400 r/min, limiting speed 3,200 r/min, mass about 8450 g.
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.