47487-47420A bearing: complete specifications & equivalents
The 47487-47420A is a ISO 355 radial bearing sized 69.85 x 120 x 32.545 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 69.85 mm |
| Outer diameter D | 120 mm |
| Width B | 32.545 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 188 kN |
| Basic static load rating C0 | 228 kN |
| Fatigue load limit Pu | 26.5 kN |
| Reference speed (thermal) | 4300 rpm |
| Limiting speed (mechanical) | 5300 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 1500 g |
| Manufacturer designation | SKF 47487/47420 A |
| 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 & 47400-series range
| Bore d | 2.75 in |
|---|---|
| Outer diameter D | 4.724 in |
| Width B | 1.281 in |
| ISO bore code | 87 |
| Radial section height (D−d)/2 | 25.1 mm |
| Smallest bore in 47400-series | 69.85 mm |
| Largest outer diameter in 47400-series | 120 mm |
| Width range across 47400-series | 32.545–32.545 mm |
| Bore position in 47400-series (smallest first) | 1 of 1 |
| Bore above smallest 47400-series size | 0 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 47487-47420-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 69.85×120×32.545 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting. |
| 47487-47420A | 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 47487-47420A model number is decoded
The 47400-series series assigns 69.85 mm bore, 120 mm OD and 32.545 mm width to 47487; the cone and cup references are not interchangeable with other inch-series pairs even when the bore matches, because the cup profile and rib geometry are series-specific. In SKF suffix language a bare 47487 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 25.1 mm radial section height ((120−69.85)/2) and 1500 g catalogue mass frame a 69.85 mm bore bearing rated at 188 kN C — roughly 2.69 kN of dynamic capacity per millimetre of bore before application factors. Mounting practice for 47487: the rotating cone takes the interference fit (k5 on a 69.85 mm shaft), the cup slides for axial location, and reversing-thrust duty demands a paired O/X set rather than one bearing. Speed envelope and thermal behaviour: at 4,300 r/min thermal reference, the 69.85 mm bore shaft runs at a dn of 300k, and the 25.1 mm section dissipates heat through the cup-to-housing contact path; the 5,300 r/min mechanical ceiling reflects cage strength, and the 1500 g spinning cone contributes gyroscopic moment under rapid speed reversal. Cone versus cup responsibility in 47487: the 47487 cone carries the 69.85 mm bore, rollers and pressed-steel cage; the 47420 A cup carries the 120 mm OD raceway, the roller-seating rib and the outer press-fit surface. The two references are not interchangeable halves.In SKF catalogue PUB BU/P1 17000, 47487 appears as SKF 47487/47420 A: an open, single-row tapered roller bearing in the 47400-series, supplied with a pressed-steel cage as standard.
Typical equipment & failure modes
Common applications
- large process pump and compressor shafts
- rolling-mill auxiliary drives
- crane sheave and hoist gearboxes
- crane sheave and hoist gearboxes
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
- uneven load sharing in a pair when spacer faces are not parallel to the bore
- axial overload spalling at the roller-rib contact beyond the single-row thrust rating
- pressed-steel cage wear or fracture after prolonged running above the limiting speed
- edge loading from shaft deflection or housing misalignment
Selection pitfalls — read before you substitute
- Mount the 69.85 mm bore 47487 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 47400-series inch series at 69.85 mm bore (120×32.545 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.
- The tapered contact angle creates an induced axial load under pure radial force; include it in the 47487 rating calculation (and account for it in both bearings of a pair) or the unloaded bearing skids its rollers.
- Setting is a design value, not an assembly feel: excessive preload in the 47487 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.
- Open 47487 units need application-supplied sealing and a defined EP lubricant supply; the roller-rib contact is the first to fail when the additive film breaks down.
- The 188/228 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 47487 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 47487/47420 A designation when purchasing and match the execution to the mounting arrangement.
Frequently asked questions
How does the 47487 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 47400-series code marks the dimensional series. The metric dimensions 69.85×120×32.545 mm are the converted equivalents of the original inch boundary dimensions.
What do the cone and cup numbers in 47487 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 (47400-series) groups sizes that share the same boundary-dimension plan.
Can a single 47487 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 47487 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 47487 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting.
What shaft and housing fits suit 47487?
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 32.545 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.