32948 bearing: complete specifications & equivalents
The 32948 is a ISO 355 radial bearing sized 240 x 320 x 51 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 240 mm |
| Outer diameter D | 320 mm |
| Width B | 51 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 624 kN |
| Basic static load rating C0 | 1080 kN |
| Fatigue load limit Pu | 96.5 kN |
| Reference speed (thermal) | 1400 rpm |
| Limiting speed (mechanical) | 1700 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 11000 g |
| Manufacturer designation | SKF 32948 |
| Standard | ISO 355 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB |
| Last verified | 2026-09-28 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB) · extracted 2026-09-28
Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB); 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 & 32900-series range
| Bore d | 9.449 in |
|---|---|
| Outer diameter D | 12.598 in |
| Width B | 2.008 in |
| ISO bore code | 48 |
| Radial section height (D−d)/2 | 40 mm |
| Smallest bore in 32900-series | 35 mm |
| Largest outer diameter in 32900-series | 600 mm |
| Width range across 32900-series | 14–100 mm |
| Bore position in 32900-series (smallest first) | 27 of 37 |
| Bore above smallest 32900-series size | 205 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 32948 | ISO 15 | full Dimensions and internal design equivalent — standard interchange. | ISO 355 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 32948 model number is decoded
For a 240 mm shaft carrying combined load, SKF lists 32948 under catalogue execution SKF 32948: one open single-row tapered roller bearing in the very-light thin section of the 32900 family.Numbering ties the bearing to its envelope: 32948 means tapered-roller type 3, very-light thin section series 29, 240 mm bore — which is why the 320×51 mm outline swaps dimensionally with other ISO 355 bearings of the same code. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. 4EC); it is the dimensional series, not a separate part number. The 96.5 kN Pu figure feeds the adjusted-life equation at contaminated or partial-film conditions, and the 1.73 C0/C balance shows this execution is tuned to thrust-heavy combined loads rather than pure radial running. Specify pairs rather than single units wherever thrust reverses: the tapered contact of 32948 generates an induced axial load under radial force, and an unpaired bearing on a reversing shaft will run slack and fret its seat. Material and manufacturing detail: the 11000 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the 32900 ISO envelope, with the pressed-steel cage contributing roughly 330 g of the total; the 240 mm bore is ground to IT5 roundness and the 320 mm OD to IT5 cylindricity, and the 51 mm width tolerance keeps the pair-setting scatter within the ISO preload class.
Typical equipment & failure modes
Common applications
- offshore winch and drawworks drums
- rolling-mill roll-neck bearings
- heavy-duty rolling-mill gearboxes
- large crusher and mineral-processing drives
Known failure patterns
- cup or cone misalignment when the separable rings are not seated square during mounting
- loose cup rotation in the housing when the specified press fit is not achieved
- axial overload spalling at the roller-rib contact beyond the single-row thrust rating
- preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways
- cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity
- hard-particle indentation of the tapered raceway in unfiltered oil
Selection pitfalls — read before you substitute
- At 240 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.
- The 329 series at 240 mm bore (320×51 mm) is the very-light thin-section envelope: the smallest OD of any tapered family at this bore, ideal where radial space is severely limited, but capacity is well below a 30248 of the same bore — confirm the L10 life and minimum axial load before choosing it.
- O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 32948 mounting error.
- When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of 32948 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.
- The 11000 g mass and 51 mm width mean spacer and abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the contact angle and concentrates load on one rib of 32948.
- The 624/1080 kN ratings are SKF catalogue 17000 values for the basic 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 and re-verify for critical drives.
- SKF lists several executions of 32948 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32948 designation when purchasing and match the execution to the mounting arrangement.
Frequently asked questions
What are the dimensions and catalogue data of 32948?
The SKF 32948 is a single-row tapered roller bearing with 240 mm bore, 320 mm outer diameter and 51 mm width (9.449 × 12.598 × 2.008 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 624 kN, C0 1080 kN, fatigue load limit Pu 96.5 kN, reference speed 1,400 r/min, limiting speed 1,700 r/min, mass about 11000 g. It is an open, separable bearing with a pressed-steel cage.
How does the 32948 bore code work?
The last two digits of 32948 are bore code 48, so 48 × 5 = 240 mm bore. The 320 mm OD and 51 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code.
What do the 32948 series and basic execution designations mean?
The leading 3 marks a single-row tapered roller bearing; the second digit 29 is the ISO 355 series (very-light thin section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution.
Can a single 32948 take axial load in both directions?
No — one single-row tapered roller bearing reacts thrust in one direction only, and under radial load its contact angle induces an axial force. Use two bearings as a matched pair: O (back-to-back) for a rigid, moment-resisting arrangement, X (face-to-face) where thermal expansion must be tolerated, or tandem where one-direction thrust is shared.
How does 32948 compare with a ball bearing of the same bore?
A tapered roller bearing has line contact and a steep contact angle: much higher combined axial-plus-radial capacity and shock resistance than a ball bearing of the same bore, at the cost of speed, one-direction thrust, mandatory pairing for reversing loads and a minimum axial load requirement. A ball bearing cannot be dropped into a combined-load 32948 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB on 2026-09-28. Read our editorial & correction policy.