HM215249-210 bearing: complete specifications & equivalents
The HM215249-210 is a ISO 355 radial bearing sized 76 x 132 x 39 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 76 mm |
| Outer diameter D | 132 mm |
| Width B | 39 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 255 kN |
| Basic static load rating C0 | 305 kN |
| Fatigue load limit Pu | 34.5 kN |
| Reference speed (thermal) | 4000 rpm |
| Limiting speed (mechanical) | 4800 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 2150 g |
| Manufacturer designation | SKF HM 215249/210 |
| Standard | ISO 355 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB |
| Last verified | 2026-09-28 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch 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. 8.2 inch 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 & HM215200-series range
| Bore d | 2.992 in |
|---|---|
| Outer diameter D | 5.197 in |
| Width B | 1.535 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 28 mm |
| Smallest bore in HM215200-series | 76 mm |
| Largest outer diameter in HM215200-series | 132 mm |
| Width range across HM215200-series | 39–39 mm |
| Bore position in HM215200-series (smallest first) | 1 of 1 |
| Bore above smallest HM215200-series size | 0 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| HM215249-210 | Timken | full Dimensions and internal design equivalent — standard interchange. | Same inch-series cone/cup boundary envelope (d/D/T); load ratings and speed limits are brand-specific and may differ. |
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 HM215249-210 model number is decoded
Reading the designation: HM215249 follows the Timken-style inch convention — the cone (inner ring with rollers) and cup (outer ring) are quoted as a pair separated by a slash, and the HM215200-series code identifies the dimensional series. The 76 mm bore, 132 mm OD and 39 mm width are the metric equivalents of the inch boundary dimensions. The SKF catalogue adds the ISO 355 dimension-series code after the bare number (e.g. ); it is the dimensional series, not a separate part number. With C 255 kN and C0 305 kN, the HM215249 pair-sizing check is dominated by the axial share: keep the equivalent load P below the rating at the required L10, remembering one bearing alone cannot cover reversing thrust at 4,800 r/min. Mounting practice for HM215249: the rotating cone takes the interference fit (k5 on a 76 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Load system: the 255 kN basic dynamic rating C and 305 kN static rating C0 give a C0/C balance of 1.20, and dividing C by the 76 mm bore yields 3.36 kN per millimetre of journal — a density metric that compares across families; the 34.5 kN fatigue limit Pu is the floor beneath which the adjusted-life calculation drops below acceptable L10 hours for a 76 mm shaft carrying variable duty. Cup-side note for 210: the outer ring's rib profile and the 132 mm outside diameter are cup-specific within the HM215200-series tables, so substituting a different cup against the same HM 215249 cone changes both the assembled 39 mm width and the axial free-play setting of the mounted pair.SKF HM 215249/210 belongs to the SKF single-row tapered roller range — the 76 mm bore entry in the inch HM215200-series, dimensioned 132 mm OD and 39 mm wide.
Typical equipment & failure modes
Common applications
- rolling-mill auxiliary drives
- crane sheave and hoist gearboxes
- paper-machine and printing rolls
- paper-machine and printing rolls
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
- false brinelling on idle paired sets exposed to machine vibration
- roller large-end smearing against the cone rib after EP lubricant film failure
- cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity
- edge loading from shaft deflection or housing misalignment
Selection pitfalls — read before you substitute
- Mount the 76 mm bore HM215249 by induction heating of the cone (max 120 °C — the pressed-steel cage sets the ceiling, not the steel); driving it home through the cup or rollers brinells the tapered raceway.
- The HM215200-series inch series at 76 mm bore (132×39 mm) follows the Timken cone/cup convention; substitutions must match both the cone and cup reference exactly — interchanging with another series or a metric 3xxxx bearing of the same bore changes OD, width and contact angle, so re-run the pair setting and shoulder-diameter checks before swapping.
- When the outer ring rotates, reverse the fit logic and provide cup location; the tapered contact of HM215249 pushes the rings apart under load, so a non-located cup walks its seat even when the shaft is fixed.
- Do not mix brands or executions inside one HM215249 pair — matched sets are ground for a specific setting, and pairing a SKF basic unit with a different suffix variant will not share the setting evenly.
- The pressed-steel cage is rated for standard industrial service; sustained running above the limiting speed or with degraded lubricant wears the cage pockets — inspect the cage at every relubrication interval.
- The 255/305 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 HM215249 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF HM 215249/210 designation when purchasing and match the execution to the mounting arrangement.
Frequently asked questions
How does the HM215249 inch-series designation work?
Inch-series tapered roller bearings use a Timken-style cone/cup convention: the number before the slash identifies the cone (inner ring with roller and cage assembly), the number after the slash identifies the cup (outer ring), and the HM215200-series code marks the dimensional series. The metric dimensions 76×132×39 mm are the converted equivalents of the original inch boundary dimensions.
What do the cone and cup numbers in HM215249 mean?
The cone number (before the slash) identifies the inner ring, rollers and cage; the cup number (after the slash) identifies the outer ring. Both are quoted together because a single-row tapered roller bearing is a matched separable pair — the cone and cup are ground to work together and are not interchangeable with arbitrary other parts. The series prefix (HM215200-series) groups sizes that share the same boundary-dimension plan.
Can a single HM215249 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 HM215249 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 HM215249 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting.
What shaft and housing fits suit HM215249?
For a rotating shaft under normal load, seat the cone on a k5 shaft fit; the cup is usually a loose-to-transition fit in the housing so it can creep slightly and distribute wear. Chamfer and shoulder diameters must clear the bearing rings so the 39 mm-wide cup seats square; the mounting setting (end play or preload) is set by the axial position of the cup relative to the cone.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.2 inch single-row TRB on 2026-09-28. Read our editorial & correction policy.