15123-15245 bearing: complete specifications & equivalents
The 15123-15245 is a ISO 355 radial bearing sized 31.75 x 62 x 18.161 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 31.75 mm |
| Outer diameter D | 62 mm |
| Width B | 18.161 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 59.5 kN |
| Basic static load rating C0 | 57 kN |
| Fatigue load limit Pu | 6.2 kN |
| Reference speed (thermal) | 9000 rpm |
| Limiting speed (mechanical) | 11000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 240 g |
| Manufacturer designation | SKF 15123/15245 |
| 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 & 15000-series range
| Bore d | 1.25 in |
|---|---|
| Outer diameter D | 2.441 in |
| Width B | 0.715 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 15.1 mm |
| Smallest bore in 15000-series | 25.4 mm |
| Largest outer diameter in 15000-series | 62 mm |
| Width range across 15000-series | 18.161–19.05 mm |
| Bore position in 15000-series (smallest first) | 2 of 2 |
| Bore above smallest 15000-series size | 6.350000000000001 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 15123-15245-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 31.75×62×18.161 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting. |
| 15123-15245 | 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 15123-15245 model number is decoded
At 9,000 r/min reference speed the 15.1 mm-section 15123 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 11,000 r/min as the mechanical ceiling. For a 31.75 mm shaft the usual cone seat is k5 with an H7 housing when the inner ring rotates; arrange two 15123 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Material and manufacturing detail: the 240 g catalogue mass reflects through-hardened bearing steel (density ~7.85 g/cm³) machined to the 15100 ISO envelope, with the pressed-steel cage contributing roughly 7 g of the total; the 31.75 mm bore is ground to IT5 roundness and the 62 mm OD to IT5 cylindricity, and the 18.161 mm width tolerance keeps the pair-setting scatter within the ISO preload class. Why the cup reference matters here: in the 15000-series tables the 15123 cone appears against several cup options. 15123 is the pairing with 15245, and that choice — not the cone — fixes the 62 mm OD, the raceway track position and the 18.161 mm assembled width.15123 is a single-row tapered roller bearing in the 15000-series inch series: a separable cone-and-cup design for combined radial and one-direction axial load, listed by SKF in SKF catalogue PUB BU/P1 17000.On the SKF nameplate, 15123 denotes a matched cone-and-cup pair: the designation is not a single number but a cone reference and cup reference joined by a slash, with the 15000-series marking the dimensional series. In SKF suffix language a bare 15123 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately.
Typical equipment & failure modes
Common applications
- pump and compressor shafts
- machine-tool spindles
- belt-driven fan and blower shafts
- differential and pinion drives
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
- axial overload spalling at the roller-rib contact beyond the single-row thrust rating
- 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
- mounting score marks when the cone is cocked over the shaft keyway or a burr
Selection pitfalls — read before you substitute
- On this 31.75 mm bore, interference and temperature rise consume clearance inside a preloaded pair; calculate the residual clearance after mounting and at operating temperature — an over-tight 15123 pair heats, loses setting control and smears the roller-rib contact.
- The 15000-series inch series at 31.75 mm bore (62×18.161 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.
- A single 15123 cannot locate the shaft axially in both directions; mounting it singly on a reversing-thrust shaft leaves one direction uncontrolled — always use an O or X matched pair for bidirectional location.
- At the 59.5 kN rating of 15123, preload class changes stiffness by tens of percent but also heat generation; select light preload for the 11,000 r/min speed end and heavier preload only where moment stiffness dominates.
- 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 59.5/57 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 15123 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 15123/15245 designation when purchasing and match the execution to the mounting arrangement.
Frequently asked questions
Can a single 15123 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 15123 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 15123 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting.
What shaft and housing fits suit 15123?
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 18.161 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.
Is 15123 interchangeable with other brands?
Inch-series tapered roller bearings follow a long-standing industry boundary plan, so cones and cups of the same basic number are generally dimensionally interchangeable across manufacturers. However, internal geometry, cage design and load ratings differ by brand, so for paired or precision applications keep both halves of the set from one manufacturer — or re-verify ratings and setting when mixing.
What are the dimensions and catalogue data of 15123?
The SKF 15123/15245 is a single-row tapered roller bearing with 31.75 mm bore, 62 mm outer diameter and 18.161 mm width (1.25 × 2.441 × 0.715 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 59.5 kN, C0 57 kN, fatigue load limit Pu 6.2 kN, reference speed 9,000 r/min, limiting speed 11,000 r/min, mass about 240 g. It is an open, separable bearing with a pressed-steel cage.
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.