25580-25522 bearing: complete specifications & equivalents
The 25580-25522 is a ISO 355 radial bearing sized 44.45 x 82.931 x 26.988 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 44.45 mm |
| Outer diameter D | 82.931 mm |
| Width B | 26.988 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 99.1 kN |
| Basic static load rating C0 | 106 kN |
| Fatigue load limit Pu | 11.8 kN |
| Reference speed (thermal) | 6700 rpm |
| Limiting speed (mechanical) | 8000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 610 g |
| Manufacturer designation | SKF 25580/25522 |
| 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 & 25500-series range
| Bore d | 1.75 in |
|---|---|
| Outer diameter D | 3.265 in |
| Width B | 1.063 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 19.2 mm |
| Smallest bore in 25500-series | 38.1 mm |
| Largest outer diameter in 25500-series | 83.058 mm |
| Width range across 25500-series | 23.812–26.988 mm |
| Bore position in 25500-series (smallest first) | 3 of 4 |
| Bore above smallest 25500-series size | 6.350000000000001 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 25580-25520-NTN | NTN | verify Commonly quoted cross reference; confirm against the target catalog before ordering. | Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue. |
| 25580-25522 | 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 25580-25522 model number is decoded
Mounting practice for 25580: the rotating cone takes the interference fit (k5 on a 44.45 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Journal and housing interface: the 44.45 mm bore takes a k5 shaft seat (upper deviation ~0.089 mm for this diameter range) and the 82.931 mm outside diameter pairs with an H7 housing bore tolerance band of 82.931.000/82.951 mm; the 26.988 mm width defines the shoulder depth, and the 610 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations. Cone-and-cup identity in 25580: the leading 25580 reference identifies the inner ring, rollers and cage; the trailing 25522 reference identifies the outer ring. The 25500-series series lists alternative cups for the same cone, each producing a different 82.931 mm OD or 26.988 mm width — hence a different SKU even though the bore stays at 44.45 mm.For a 44.45 mm shaft carrying combined load, SKF lists 25580 under catalogue execution SKF 25580/25522: one open single-row tapered roller bearing in the inch 25500-series.Reading the designation: 25580 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 25500-series code identifies the dimensional series. The 44.45 mm bore, 82.931 mm OD and 26.988 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 99.1 kN and C0 106 kN, the 25580 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 8,000 r/min.
Typical equipment & failure modes
Common applications
- axle-boxes in material-handling equipment
- automotive and light-truck wheel hubs
- industrial gearbox shafts and reducers
- automotive and light-truck wheel hubs
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
- thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting
- false brinelling on idle paired sets exposed to machine vibration
- 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 44.45 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 25580 pair heats, loses setting control and smears the roller-rib contact.
- The 25500-series inch series at 44.45 mm bore (82.931×26.988 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 25580 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.
- A single 25580 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.
- Catalogue reference speed and limiting speed are different limits: the 6,700 r/min reference is a thermal criterion under load, while the 8,000 r/min limiting value is the mechanical ceiling — observe both.
- The 99.1/106 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 25580 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 25580/25522 designation when purchasing and match the execution to the mounting arrangement.
Frequently asked questions
How does 25580 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 25580 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting.
What shaft and housing fits suit 25580?
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 26.988 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 25580 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 25580?
The SKF 25580/25522 is a single-row tapered roller bearing with 44.45 mm bore, 82.931 mm outer diameter and 26.988 mm width (1.75 × 3.265 × 1.063 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 99.1 kN, C0 106 kN, fatigue load limit Pu 11.8 kN, reference speed 6,700 r/min, limiting speed 8,000 r/min, mass about 610 g. It is an open, separable bearing with a pressed-steel cage.
How does the 25580 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 25500-series code marks the dimensional series. The metric dimensions 44.45×82.931×26.988 mm are the converted equivalents of the original inch boundary dimensions.
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.