331945 bearing: complete specifications & equivalents
The 331945 is a ANSI ABMA 19.2 radial bearing sized 228.6 x 488.95 x 254 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 228.6 mm |
| Outer diameter D | 488.95 mm |
| Width B | 254 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 3143 kN |
| Basic static load rating C0 | 4500 kN |
| Fatigue load limit Pu | 390 kN |
| Operating temperature | -40 to +120 °C |
| Mass | 205000 g |
| Manufacturer designation | SKF 331945 |
| Standard | ANSI ABMA 19.2 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants |
| Last verified | 2026-09-29 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants) · extracted 2026-09-29
Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants); 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 & tdo-series range
| Bore d | 9 in |
|---|---|
| Outer diameter D | 19.25 in |
| Width B | 10 in |
| ISO bore code | 45 |
| Radial section height (D−d)/2 | 130.2 mm |
| Smallest bore in tdo-series | 101.6 mm |
| Largest outer diameter in tdo-series | 596.9 mm |
| Width range across tdo-series | 49.212–284 mm |
| Bore position in tdo-series (smallest first) | 3 of 23 |
| Bore above smallest tdo-series size | 127 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 331945 | 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 331945 model number is decoded
Material and manufacturing detail: the 205000 g catalogue mass reflects through-hardened bearing steel machined to the listed envelope; ring roundness and width tolerance keep the mounted-setting scatter inside the catalogue class. Variant check: catalogue siblings of 331945 carry different variant suffixes at the same boundary dimensions; the TDO/D code on this unit is not a cosmetic mark — it fixes the internal setting and must match on replacement. TDO mounting: the double cup is clamped in the housing and the two cones take interference on the 228.6 mm shaft; press force goes through the cone faces only — driving through the rollers brinells both raceways at once.The SKF 331945 is a 228.6×488.95×254 mm TDO double-row tapered roller bearing — two roller rows on a common double cup, delivered clearance-set as one assembly weighing 205.0 kg.Reading the designation: 331945 is the SKF double-row base number tied to the 228.6 mm bore and 488.95 mm OD, and the TDO/D suffix identifies the internal design variant — cup/cone configuration, spacer execution and clearance class are encoded there rather than in a generic suffix. At 205.0 kg the 331945 assembly needs mechanical handling at mounting — sling through the bore or use lifting eyes on the shaft, and never lift the unit by one ring alone: the rings are separable. Mass 205.0 kg over a 228.6×488.95×254 mm envelope: the steel content itself is a heat sink, but the two roller rows generate roughly twice the friction of a single-row bearing of the same bore.
Typical equipment & failure modes
Common applications
- offshore winch and drawworks drums
- rolling-mill roll-neck bearings
- heavy-duty rolling-mill gearboxes
- rolling-mill roll-neck bearings
Known failure patterns
- axial clamping ring bolt relaxation that lets the clearance-set rows walk apart under reversing thrust
- axial clamping ring bolt relaxation that lets the clearance-set rows walk apart under reversing thrust
- cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity
- brinelling from pressing the cone or cup home through the rollers
- grease degradation after long shelf storage without rotation or re-greasing
Selection pitfalls — read before you substitute
- Lifting 331945 by one ring separates the assembly; sling through the 228.6 mm bore or use the shaft as the lifting member.
- Contamination control matters twice over for double-row units: particles trapped between the rows of 331945 cannot migrate out, so flush the housing before assembly and fit filtration matched to the oil flow.
- Lifting 331945 by one ring separates the assembly; sling through the 228.6 mm bore or use the shaft as the lifting member.
- The 3143/4500 kN ratings are SKF catalogue 17000 values for this execution; 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 SKF 331945 designation when purchasing — base-number-only orders are ambiguous across executions and variants.
Frequently asked questions
What are the dimensions and catalogue data of 331945?
The SKF 331945 is a double-row tapered roller bearing of TDO design with 228.6 mm bore, 488.95 mm outer diameter and 254 mm overall width (9 × 19.25 × 10 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 3143 kN, C0 4500 kN, fatigue load limit Pu 390 kN, mass about 205.00 kg.
What does the TDO/D variant code on 331945 mean?
Double-row tapered bearings of this size follow SKF works numbering: the base number 331945 fixes the 228.6×488.95×254 mm envelope, and the TDO/D code identifies the internal design variant — spacer execution, rib detail and clearance class. Same-envelope units under a different variant are not interchangeable without checking the variant meaning.
Why does the catalogue list no speed rating for 331945?
Bearings of this size class run in slow, heavily loaded machinery where the permissible speed is set by the application heat balance rather than a universal table value. Plan lubrication and cooling against the 205.0 kg assembly mass and instrument the first run with temperature logging.
Can components of 331945 be interchanged with another unit of the same base number?
No — cones, cups and spacers of a double-row set are matched per serial and the clearance is set by selective grinding at the factory. Replace 331945 as a complete assembly in the same TDO/D variant.
How does 331945 react axial load?
The TDO design works as a fixed X arrangement: one double cup with two cones locates the shaft in both axial directions, with load shared between the two rows according to the factory-set clearance.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants on 2026-09-29. Read our editorial & correction policy.