497-492A bearing: complete specifications & equivalents
The 497-492A is a ISO 355 radial bearing sized 85.725 x 133.35 x 30.163 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 85.725 mm |
| Outer diameter D | 133.35 mm |
| Width B | 30.163 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 178 kN |
| Basic static load rating C0 | 220 kN |
| Fatigue load limit Pu | 25.5 kN |
| Reference speed (thermal) | 3800 rpm |
| Limiting speed (mechanical) | 4500 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 1450 g |
| Manufacturer designation | SKF 497/492 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 & 495-series range
| Bore d | 3.375 in |
|---|---|
| Outer diameter D | 5.25 in |
| Width B | 1.188 in |
| ISO bore code | 97 |
| Radial section height (D−d)/2 | 23.8 mm |
| Smallest bore in 495-series | 85.725 mm |
| Largest outer diameter in 495-series | 133.35 mm |
| Width range across 495-series | 30.163–30.163 mm |
| Bore position in 495-series (smallest first) | 1 of 1 |
| Bore above smallest 495-series size | 0 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 497-492A-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 85.725×133.35×30.163 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting. |
| 497-492A | 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 497-492A model number is decoded
SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. At 3,800 r/min reference speed the 23.8 mm-section 497 is governed thermally by preload and lubricant flow; grease or oil selection should be made against that value, with 4,500 r/min as the mechanical ceiling. Because the contact line is tapered, one 497 reacts thrust in a single direction; bidirectional shafts need an O or X pair, and a rotating cone on a 85.725 mm shaft typically takes a k5 seat with an H7 housing bore. Speed envelope and thermal behaviour: at 3,800 r/min thermal reference, the 85.725 mm bore shaft runs at a dn of 326k, and the 23.8 mm section dissipates heat through the cup-to-housing contact path; the 4,500 r/min mechanical ceiling reflects cage strength, and the 1450 g spinning cone contributes gyroscopic moment under rapid speed reversal. Cup-side note for 492 A: the outer ring's rib profile and the 133.35 mm outside diameter are cup-specific within the 495-series tables, so substituting a different cup against the same 497 cone changes both the assembled 30.163 mm width and the axial free-play setting of the mounted pair.SKF 497 (SKF 497/492 A) is the 495-series tapered roller choice for a 85.725 mm shaft — one row of tapered rollers on an asymmetric raceway inside the 133.35×30.163 mm envelope.Reading the designation: 497 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 495-series code identifies the dimensional series. The 85.725 mm bore, 133.35 mm OD and 30.163 mm width are the metric equivalents of the inch boundary dimensions.
Typical equipment & failure modes
Common applications
- paper-machine and printing rolls
- construction machinery drives
- marine deck machinery shafts
- large process pump and compressor shafts
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
- preload loss as the mounted pair relaxes, letting rollers skid and smear the raceways
- uneven load sharing in a pair when spacer faces are not parallel to the bore
- pressed-steel cage wear or fracture after prolonged running above the limiting speed
- rolling-contact fatigue spalling after the rated L10 life is exceeded
Selection pitfalls — read before you substitute
- Mount the 85.725 mm bore 497 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 495-series inch series at 85.725 mm bore (133.35×30.163 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.
- Setting is a design value, not an assembly feel: excessive preload in the 497 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.
- Do not mix brands or executions inside one 497 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.
- Never press both rings through the wrong element during fitting: force for an interference shaft seat goes through the cone only, or brinell marks on the 133.35 mm cup race release as noise within the first running hours.
- The 178/220 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 497 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 497/492 A designation when purchasing and match the execution to the mounting arrangement.
Frequently asked questions
What do the cone and cup numbers in 497 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 (495-series) groups sizes that share the same boundary-dimension plan.
Can a single 497 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 497 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 497 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting.
What shaft and housing fits suit 497?
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 30.163 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 497 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.
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.