23976 bearing: complete specifications & equivalents
The 23976 is a ISO 15 radial bearing sized 380 x 520 x 106 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 | 520 mm |
| Width B | 106 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 2011 kN |
| Basic static load rating C0 | 3800 kN |
| Fatigue load limit Pu | 285 kN |
| Reference speed (thermal) | 1100 rpm |
| Limiting speed (mechanical) | 1200 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 69000 g |
| Manufacturer designation | SKF 23976 CC/W33 |
| Standard | ISO 15 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 9.1 spherical roller bearings |
| Last verified | 2026-09-26 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 9.1 spherical roller bearings) · extracted 2026-09-26
Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 9.1 spherical 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 & 23900-series range
| Bore d | 14.961 in |
|---|---|
| Outer diameter D | 20.472 in |
| Width B | 4.173 in |
| ISO bore code | 76 |
| Radial section height (D−d)/2 | 70 mm |
| Smallest bore in 23900-series | 180 mm |
| Largest outer diameter in 23900-series | 650 mm |
| Width range across 23900-series | 52–128 mm |
| Bore position in 23900-series (smallest first) | 12 of 17 |
| Bore above smallest 23900-series size | 200 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 23976 | ISO 15 | full Dimensions and internal design equivalent — standard interchange. | ISO 15 boundary-dimension envelope; D/B cross-verified against Schaeffler HR1 2022; brand-specific OEM equivalents (NSK/FAG/NTN) pending multi-source data. |
| 23976-CCK-W33 | SKF | full Dimensions and internal design equivalent — standard interchange. | Tapered-bore (1:12) execution on OH3976 adapter sleeve; same ISO 15 envelope, separate order number. |
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 23976 model number is decoded
The 23976 CC/W33 is a 380×520×106 mm spherical roller bearing — the dimension series 39 (compact OD, narrow) entry for a 380 mm shaft, with two rows of symmetrical barrel rollers for combined radial and axial load. Reading the designation: the leading 2 marks a spherical roller bearing, the 39 is the ISO 15 dimension series (dimension series 39 (compact OD, narrow)), and the last two digits encode the 380 mm bore; the 520 mm OD and 106 mm width follow the ISO 15 general plan. SKF basic executions here are E or CC/W33; specialist suffixes change the bearing materially — VA405 for vibrating screens (C4 clearance, surface-hardened cage), 2CS5 for the sealed variant — and must be quoted in full when ordering. Selection arithmetic: the C0/C ratio is about 1.89 (static 3800 kN against dynamic 2011 kN), typical of a spherical roller sized for heavy combined loads, and the 285 kN fatigue load limit Pu is the equivalent-load floor used in the life calculation. For relubrication, route the grease duct to the outer-ring W33 groove position where fitted, and purge until fresh grease appears at the seal — the 106 mm width across two roller rows needs the full charge.
Typical equipment & failure modes
Common applications
- SAG and ball-mill drive shafts
- large mining crusher main shafts
- wind-turbine main shaft support
- heavy rolling-mill work-roll chocks
Known failure patterns
- raceway fatigue spalling of the sphered outer raceway after extended service above the catalogue L10 rating
- inner-ring raceway spalling from edge loading when misalignment exceeds the self-aligning recovery range
- stamped-steel cage fatigue after long service in high-vibration screening duty without the VA405 execution
- roller-end scoring from starved lubricant at start-up before the grease channel purges
- rolling-contact fatigue spalling after the rated L10 life is exceeded
Selection pitfalls — read before you substitute
- At 380 mm bore the ring mass makes cocking during mounting a real risk; guide the bearing square, confirm seat contact around the full circumference, and re-check the self-aligning swing after the housing cap is torqued down.
- The 23900-series series at 380 mm bore (520×106 mm) is the slim-OD envelope: it buys radial space but gives up capacity against a 222-series bearing of the same bore — confirm the L10 margin before downsizing into it.
- The self-aligning feature is not a license to ignore alignment: beyond ≈ 0.5–2.5° (series-dependent) the edge loading eats the fatigue margin, and seal drag grows as the rings tilt.
- Shaft and housing fillets must clear the bearing chamfer so the 106 mm-wide rings seat square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.
- The 2011/3800 kN ratings are SKF catalogue values for this exact execution (23976 CC/W33); SKF can revise internal geometry without changing the order number, so keep the catalogue version (SKF catalogue PUB BU/P1 17000) with the specification and re-verify for critical drives.
- SKF lists several executions of 23976 (cylindrical bore as listed, tapered-bore 23976 CCK/W33 variant, plus sealed and vibrating-screen options in the same envelope); they are not interchangeable order numbers — quote the full 23976 CC/W33 designation when purchasing.
Frequently asked questions
What are the dimensions and catalogue data of 23976?
The 23976 CC/W33 is a double-row spherical roller bearing with 380 mm bore, 520 mm outer diameter and 106 mm width (14.961 × 20.472 × 4.173 in) per ISO 15. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 2011 kN, C0 3800 kN, fatigue load limit Pu 285 kN, reference speed 1,100 r/min, limiting speed 1,200 r/min, mass about 69000 g. It is an open, self-aligning bearing with two pressed-steel cages with a floating guide ring.
How does the 23976 bore code work?
The last two digits of 23976 are bore code 76, so 76 × 5 = 380 mm bore. The 520 mm OD and 106 mm width come from the ISO 15 dimension-series plan (dimension series 39 (compact OD, narrow)), shared with other spherical roller bearings of the same code.
What does the CC/W33 suffix mean on 23976?
CC denotes two pressed-steel cages with a floating guide ring between the roller rows, and W33 adds an annular groove plus three lubrication holes in the outer ring for relubrication. CCK/W33 is the 1:12 tapered-bore counterpart.
Can 23976 accommodate misalignment and axial load?
Yes on both counts. The sphered outer raceway lets the bearing self-align ≈ 0.5–2.5° depending on series, absorbing shaft deflection and housing-seat errors. The two barrel-roller rows also carry bidirectional axial load in addition to heavy radial load — this is the key difference from cylindrical roller bearings, which take no axial load.
When should the tapered-bore 23976K variant be used instead?
Choose the K (1:12 tapered bore) variant when the bearing must seat on an adapter or withdrawal sleeve — typical for long shafts, frequent dismounting, or stepped shafts where machining a precision journal is impractical. Sleeve mounting requires measuring clearance reduction or axial drive-up, not nut torque. The cylindrical-bore 23976 listed here seats directly on a machined journal.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 9.1 spherical roller bearings on 2026-09-26. Read our editorial & correction policy.