331951 bearing: complete specifications & equivalents
The 331951 is a ANSI ABMA 19.2 radial bearing sized 300.038 x 422.275 x 150.812 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 300.038 mm |
| Outer diameter D | 422.275 mm |
| Width B | 150.812 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 2177 kN |
| Basic static load rating C0 | 4750 kN |
| Fatigue load limit Pu | 400 kN |
| Operating temperature | -40 to +120 °C |
| Mass | 70000 g |
| Manufacturer designation | SKF 331951 |
| 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 & tdi-series range
| Bore d | 11.813 in |
|---|---|
| Outer diameter D | 16.625 in |
| Width B | 5.937 in |
| ISO bore code | 51 |
| Radial section height (D−d)/2 | 61.1 mm |
| Smallest bore in tdi-series | 203.2 mm |
| Largest outer diameter in tdi-series | 595 mm |
| Width range across tdi-series | 84–263.525 mm |
| Bore position in tdi-series (smallest first) | 5 of 25 |
| Bore above smallest tdi-series size | 96.83800000000002 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 331951 | 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 331951 model number is decoded
TDI mounting: the double cone takes the m6 shaft seat at 300.038 mm bore, and the two single cups are seated separately in the housing — check cup-face contact around the full circumference before axial clamping.SKF 331951 belongs to the SKF TDI double-row range — the 300.038 mm bore entry with a 422.275 mm outside diameter and 150.812 mm overall width, typical for rolling-mill and heavy industrial shafts.On the SKF nameplate, 331951 reads as base 331951 in the TDI/GWIY2 design variant; boundary dimensions 300.038×422.275×150.812 mm come from the base number, while clearance setting and spacer style come from the variant. Wear pattern reading at overhaul: the two rows of 331951 should show symmetric raceway contact; one-sided wear points to housing misalignment or a cocked seat rather than to a material defect. Mass 70.0 kg over a 300.038×422.275×150.812 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. Material and manufacturing detail: the 70000 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. When cross-referencing 331951, note that the TDI/GWIY2 variant is part of the SKF works designation: same-envelope units under another variant code can differ in clearance class and load rating even though d/D/T match.
Typical equipment & failure modes
Common applications
- heavy-duty rolling-mill gearboxes
- large crusher and mineral-processing drives
- wind-turbine main shafts
- offshore winch and drawworks drums
Known failure patterns
- brinelling of both raceways when mounting force is transmitted through the roller complement
- brinelling of both raceways when mounting force is transmitted through the roller complement
- pressed-steel cage wear or fracture after prolonged running above the limiting speed
- mounting score marks when the cone is cocked over the shaft keyway or a burr
- hard-particle indentation of the tapered raceway in unfiltered oil
Selection pitfalls — read before you substitute
- Never adjust the clearance of 331951 in the field: the two rows are set by ground spacers at the factory, and shim experiments on a 70.0 kg assembly usually end in overheated rows.
- Contamination control matters twice over for double-row units: particles trapped between the rows of 331951 cannot migrate out, so flush the housing before assembly and fit filtration matched to the oil flow.
- Lifting 331951 by one ring separates the assembly; sling through the 300.038 mm bore or use the shaft as the lifting member.
- The 2177/4750 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 331951 designation when purchasing — base-number-only orders are ambiguous across executions and variants.
Frequently asked questions
What are the dimensions and catalogue data of 331951?
The SKF 331951 is a double-row tapered roller bearing of TDI design with 300.038 mm bore, 422.275 mm outer diameter and 150.812 mm overall width (11.813 × 16.625 × 5.937 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 2177 kN, C0 4750 kN, fatigue load limit Pu 400 kN, mass about 70.00 kg.
What does the TDI/GWIY2 variant code on 331951 mean?
Double-row tapered bearings of this size follow SKF works numbering: the base number 331951 fixes the 300.038×422.275×150.812 mm envelope, and the TDI/GWIY2 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 331951?
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 70.0 kg assembly mass and instrument the first run with temperature logging.
Can components of 331951 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 331951 as a complete assembly in the same TDI/GWIY2 variant.
How does 331951 react axial load?
The TDI design works as a fixed O arrangement: one double cone between two single cups gives a wide load spread and high moment stiffness while reacting thrust in both directions through the two rows.
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.