AXW12 bearing: complete specifications & equivalents
The AXW12 is a ISO 3031 radial bearing sized 12 x 29 x 3.2 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 12 mm |
| Outer diameter D | 29 mm |
| Width B | 3.2 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 9.15 kN |
| Basic static load rating C0 | 30 kN |
| Fatigue load limit Pu | 3.45 kN |
| Reference speed (thermal) | 5000 rpm |
| Limiting speed (mechanical) | 10000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 9.1 g |
| Manufacturer designation | AXW 12 |
| Standard | ISO 3031 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 12.2 needle roller thrust bearings with a centring flange |
| Last verified | 2026-09-27 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 12.2 needle roller thrust bearings with a centring flange) · extracted 2026-09-27
Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 12.2 needle roller thrust bearings with a centring flange); 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 & AXW-series range
| Bore d | 0.472 in |
|---|---|
| Outer diameter D | 1.142 in |
| Width B | 0.126 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 8.5 mm |
| Smallest bore in AXW-series | 10 mm |
| Largest outer diameter in AXW-series | 68 mm |
| Width range across AXW-series | 3.2–4.2 mm |
| Bore position in AXW-series (smallest first) | 2 of 9 |
| Bore above smallest AXW-series size | 2 mm |
Cross references & equivalents
No verified interchange data yet. Send an inquiry and our team will confirm equivalents manually.
How the AXW12 model number is decoded
AXW 12 is a needle roller thrust bearing with an integral centring spigot: an AXK-style needle cage running against a hardened thrust washer whose 16 mm spigot flange locates the unit in the housing register, sized 12×29×3.2 mm overall. AXW numbering gives the bore directly (12 mm for AXW 12); the needle set inside is the AXK 1226 track with 9.15 kN dynamic rating. The integrated washer carries a 16 mm centring spigot (3 mm flange height) that locates the whole unit in a matching housing register bore — the 12 mm bore clears the shaft and does no radial piloting. One direction only: AXW 12 cannot be reversed to take opposite thrust — mirror a second bearing for reversing shafts, and keep housing and shaft seats square within the ISO 104 tolerances. Mounting: locate the 16 mm spigot in the housing register bore (at least 3 mm deep), pass the 12 mm bore over the shaft without forcing a pilot fit, and fit a separate LS/AS washer or a hardened 58–64 HRC face on the opposite side.
Typical equipment & failure modes
Common applications
- material-handling swivel joints using the spigot as a built-in housing pilot
- transmission shafts where a one-piece spigot-centred thrust unit replaces a loose cage-and-washer stack at the housing register
- automotive selector and shift mechanisms needing a pre-centred flanged thrust support in a shallow housing bore
- agricultural gear drives assembled through a housing cover, where the spigot keeps the needle set concentric until the cover is bolted
Known failure patterns
- opposing-track scoring when the separate LS/AS washer or hardened 58–64 HRC face is missing or undersized
- roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)
- instant raceway scoring when the assembly runs against a face below 58 HRC or with a rough finish
- rolling-contact fatigue spalling after the catalogue L10 life is exhausted
Selection pitfalls — read before you substitute
- At 12 mm bore the 16 mm spigot lip is thin enough to bend with pliers — handle AXW 12 by the washer face, never by the flange.
- the 5,000 r/min reference speed is the thermal criterion under load, limiting speed 10,000 r/min; the open needle set needs the housing to keep grit out.
- One-direction thrust: reversing force dumps the needles off the 25 mm outer track — mirror a second spigot-flanged unit where the load reverses.
- The spigot pilots in the housing register, not on the shaft: turning the 12 mm bore into a tight pilot fit, or omitting the 16 mm register bore, defeats the centring function of AXW 12.
- AXW is not an ISO-standardized interchangeable outline for every maker — check the 29×3.2 mm envelope and the 16 mm spigot before cross-brand substitution.
- The 9.15/30 kN ratings and 9.1 g mass are SKF catalogue values transcribed from ch. 12.2 of PUB BU/P1 17000 (PDF table page 912); mounting data — Ea/Eb raceway diameters, the flange register and the load factor — appears in the running text because the structured record carries the boundary envelope only.
Frequently asked questions
Which dimensions does the AXW 12 have?
A AXW 12 measures 12 mm bore × 29 mm outside diameter × 3.2 mm width (0.472 × 1.142 × 0.126 in). From SKF catalogue PUB BU/P1 17000: dynamic C 9.15 kN, static C0 30 kN, fatigue limit Pu 3.45 kN, reference speed 5,000 r/min, limiting speed 10,000 r/min, mass about 9.1 g. Centring spigot D1 16 mm, spigot height B1 3 mm, contact band Ea 14–25 mm.
What does AXW mean versus AXK?
AXW pairs an AXK needle set with a washer that has an integral centring spigot — the spigot locates in a housing register and keeps the set concentric as one part; AXK is the bare cage needing two separate washers. A separate LS/AS washer or hardened face is still required opposite, and the outline is not multi-brand interchangeable.
Can the AXW 12 take radial load?
No. The spigot is a locating pilot, not a radial bearing: the needle set carries one-direction thrust (9.15 kN dynamic) and the shaft arrangement carries all radial force.
Does the AXW 12 run in both axial directions?
No — one direction only. Reversing thrust lifts the needles off the 25 mm outer track; mirror a second spigot-flanged unit for reversing shafts.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 12.2 needle roller thrust bearings with a centring flange on 2026-09-27. Read our editorial & correction policy.