H-3128 adapter sleeve: complete specifications & mounting data
The H-3128 is an adapter sleeve sized 140 x 180 x 97 mm (tapered bore x sleeve OD x width) for a plain 125 mm metric shaft with M 140x2 thread supplied with the KM 28 lock nut at 4,100 g per ISO 2982-1. Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 140 mm |
| Outer diameter D | 180 mm |
| Width B | 97 mm |
| Fits shaft diameter | 125 mm |
| Sleeve thread G | M 140x2 |
| Included lock nut | KM 28 |
| Included locking device | MB 28 |
| Associated hydraulic nut | HMV 28 E |
| Material | Carbon_Steel |
| Mass | 4100 g |
| Manufacturer designation | H 3128 |
| 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 | 5.512 in |
|---|---|
| Outer diameter D | 7.087 in |
| Width B | 3.819 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 20 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) | 5 of 11 |
| Bore above smallest H31-series size | 40 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-3128 model number is decoded
mounting and dismounting stay purely mechanical: the KM 28 nut drives the taper home, and backing the nut off releases the 140 mm seat without oil-injection tooling the sleeve wall is 20 mm thick at the small end — 14.3% of the 140 mm bore — thin enough to contract evenly onto the 125 mm shaft while keeping the seat round under the clamping load the KM 28 lock nut carries size index 28, matching the bore-code family of the 140 mm seat; the nut engages the M 140x2 sleeve thread over its full width for controlled drive-up the catalogue pairs this seat with the HMV 28 E hydraulic nut (size 28); at 4,100 g the sleeve and bearing together are too heavy to seat reliably with a hook spanner alone this sleeve mounts a bearing with a 140 mm tapered bore onto a plain 125 mm shaft; the 180 mm outside diameter and 97 mm width define the tapered seat the bearing is driven onto at 125 mm shaft this is a large sleeve — the 4,100 g mass and long taper seat mean mounting uses a hydraulic nut plus feeler-gauge measurement, not torque alone reading H 3128: H marks the standard sleeve execution, the size code encodes the 140 mm tapered bore, and the kit includes the KM 28 nut plus MB 28 washer for positive locking the H31 designation block places it in the large-size H 31 range for 231..K spherical roller bearings — every sleeve in the block uses the same bore-code logic, and here the 140 mm tapered bore matches the K-suffix bearing it is ordered for hardware on this row: the KM 28 lock nut and the MB 28 locking washer; SKF lists the HMV 28 E hydraulic nut for mounting and dismounting typical applications include textile machine roller shafts, gearbox input and output shafts and woodworking saw and planer spindles adapter sleeves earn their place wherever a tapered-bore bearing must sit at any axial position on a plain shaft — here a 140 mm bore bearing on a 125 mm shaft in woodworking saw and planer spindles the sleeve lets the designer use a plain, unstepped shaft and still locate the bearing positively; only one shoulder is needed, opposite the KM 28 nut kit identity for this seat: sleeve H 3128 for a 125 mm shaft, 140x180x97 mm taper, M 140x2 thread, KM 28 nut with MB 28 washer, drive-up tool HMV 28 E, catalogue mass 4,100 g
Typical equipment & failure modes
Common applications
- marine winch and deck machinery shafts
- textile machine roller shafts
- cement plant kiln and mill trunnion drives
- food processing line drive shafts
Known failure patterns
- hammering the sleeve directly instead of driving through the nut damages the 97 mm slit edge
- bending more than one washer tab to force alignment work-hardens both tabs; choose the single closest slot only
- driving the bearing via the outer ring during mounting loads the rolling elements; force is always applied through the lock nut on the inner ring
- 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
- over-driving the taper eliminates bearing internal clearance entirely; clearance reduction must be measured with feeler gauges, not estimated from nut torque
Selection pitfalls — read before you substitute
- hammering the sleeve directly instead of driving through the nut damages the 97 mm slit edge
- driving the bearing via the outer ring during mounting loads the rolling elements; force is always applied through the lock nut on the inner ring
- greasing the tapered seat or shaft destroys the dry friction the joint relies on; a lubricated taper can let the whole sleeve spin under load
Frequently asked questions
What shaft size does the H-3128 adapter sleeve fit?
H-3128 (H 3128) mounts on a plain metric shaft of 125 mm and carries a bearing with a 140 mm tapered (K) bore; sleeve OD is 180 mm and width 97 mm.
What does the H 3128 designation mean?
H identifies a standard metric adapter sleeve in the H31 series; the size code encodes the 140 mm tapered bore (bore code × 5 mm).
What is supplied with the H-3128?
The kit contains the KM 28 lock nut and MB 28 locking washer. The HMV 28 E hydraulic nut is the associated mounting tool.
How much does the H-3128 adapter sleeve weigh?
The listed mass is 4,100 g for the sleeve assembly at 140x180x97 mm — about 42.3 g per millimetre of sleeve width.
How is the H-3128 mounted on the shaft?
Lubricate the M 140x2 thread lightly, screw the KM 28 home, then tighten to the catalogue axial displacement while measuring clearance reduction on the 140 mm bearing, and finally bend the MB 28 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.