H-3124 adapter sleeve: complete specifications & mounting data
The H-3124 is an adapter sleeve sized 120 x 155 x 88 mm (tapered bore x sleeve OD x width) for a plain 110 mm metric shaft with M 120x2 thread supplied with the KM 24 lock nut at 2,500 g per ISO 2982-1. Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 120 mm |
| Outer diameter D | 155 mm |
| Width B | 88 mm |
| Fits shaft diameter | 110 mm |
| Sleeve thread G | M 120x2 |
| Included lock nut | KM 24 |
| Included locking device | MB 24 |
| Associated hydraulic nut | HMV 24 E |
| Material | Carbon_Steel |
| Mass | 2500 g |
| Manufacturer designation | H 3124 |
| Standard | ISO 2982-1 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 23.1 adapter sleeves for metric shafts |
| Last verified | 2026-09-30 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 23.1 adapter sleeves for metric shafts) · extracted 2026-09-30
Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 23.1 adapter sleeves for metric shafts); 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 & H31-series range
| Bore d | 4.724 in |
|---|---|
| Outer diameter D | 6.102 in |
| Width B | 3.465 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 17.5 mm |
| Smallest bore in H31-series | 100 mm |
| Largest outer diameter in H31-series | 250 mm |
| Width range across H31-series | 76–150 mm |
| Bore position in H31-series (smallest first) | 3 of 11 |
| Bore above smallest H31-series size | 20 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| H | ISO 15 | full Dimensions and internal design equivalent — standard interchange. | ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier. |
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 H-3124 model number is decoded
the seat taper is 1:12, so each millimetre of axial drive-up removes about 1/12 mm of radial clearance; one turn of the KM 24 nut on the M 120x2 thread advances 2 mm and takes out roughly 0.167 mm of clearance mounting and dismounting stay purely mechanical: the KM 24 nut drives the taper home, and backing the nut off releases the 120 mm seat without oil-injection tooling the KM 24 lock nut carries size index 24, matching the bore-code family of the 120 mm seat; the nut engages the M 120x2 sleeve thread over its full width the sleeve wall is 17.5 mm thick at the small end — 14.6% of the 120 mm bore — thin enough to contract evenly onto the 110 mm shaft while keeping the seat round under the clamping load a width-to-bore ratio of 0.73 gives a 88 mm tapered contact length; the longitudinal slit lets the sleeve close down radially, so the grip on the 110 mm shaft is purely frictional at 110 mm shaft the sleeve suits mid-size machinery — conveyor pulleys, industrial fans and gearbox output shafts carrying 120 mm bore bearings H identifies the conventional sleeve used by maintenance crews worldwide: tighten KM 24, verify clearance, lock with one MB 24 tab, and the 110 mm shaft needs no thread or step dimensionally this sleeve belongs to the large-size H 31 range for 231..K spherical roller bearings; the 155 mm OD and 88 mm width follow the ISO 2982-1 boundary plan for that series hardware on this row: the KM 24 lock nut and the MB 24 locking washer; SKF lists the HMV 24 E hydraulic nut for mounting and dismounting typical applications include food processing line drive shafts, electric motor and generator shafts and quarry conveyor head and tail drums adapter sleeves earn their place wherever a tapered-bore bearing must sit at any axial position on a plain shaft — here a 120 mm bore bearing on a 110 mm shaft in quarry conveyor head and tail drums the sleeve lets the designer use a plain, unstepped shaft and still locate the bearing positively; only one shoulder is needed, opposite the KM 24 nut kit identity for this seat: sleeve H 3124 for a 110 mm shaft, 120x155x88 mm taper, M 120x2 thread, KM 24 nut with MB 24 washer, drive-up tool HMV 24 E, catalogue mass 2,500 g
Typical equipment & failure modes
Common applications
- printing press cylinder journals
- food processing line drive shafts
- conveyor pulley and drum bearing seats
- industrial fan and blower impeller shafts
Known failure patterns
- a plain KM nut used without its MB washer has no anti-rotation feature and will unthread under vibration
- over-driving the taper eliminates bearing internal clearance entirely; clearance reduction must be measured with feeler gauges, not estimated from nut torque
- misaligning the slit with the load zone or belt-pull direction concentrates stress on the split; orient the slit away from the main load
- hammering the sleeve directly instead of driving through the nut damages the 88 mm slit edge
- the shaft must be within h9 tolerance and free of scoring; an oversize or rough shaft stops the slit sleeve closing down and leaves the grip to the thread alone
Selection pitfalls — read before you substitute
- a plain KM nut used without its MB washer has no anti-rotation feature and will unthread under vibration
- misaligning the slit with the load zone or belt-pull direction concentrates stress on the split; orient the slit away from the main load
- hammering the sleeve directly instead of driving through the nut damages the 88 mm slit edge
Frequently asked questions
What shaft size does the H-3124 adapter sleeve fit?
H-3124 (H 3124) mounts on a plain metric shaft of 110 mm and carries a bearing with a 120 mm tapered (K) bore; sleeve OD is 155 mm and width 88 mm.
What does the H 3124 designation mean?
H identifies a standard metric adapter sleeve in the H31 series; the size code encodes the 120 mm tapered bore (bore code × 5 mm).
What is supplied with the H-3124?
The kit contains the KM 24 lock nut and MB 24 locking washer. The HMV 24 E hydraulic nut is the associated mounting tool.
How much does the H-3124 adapter sleeve weigh?
The listed mass is 2,500 g for the sleeve assembly at 120x155x88 mm — about 28.4 g per millimetre of sleeve width.
How is the H-3124 mounted on the shaft?
Lubricate the M 120x2 thread lightly, screw the KM 24 home, then tighten to the catalogue axial displacement while measuring clearance reduction on the 120 mm bearing, and finally bend the MB 24 washer tab.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 23.1 adapter sleeves for metric shafts on 2026-09-30. Read our editorial & correction policy.