544091-544118 bearing: complete specifications & equivalents
The 544091-544118 is a ISO 355 radial bearing sized 231.775 x 300.038 x 33.338 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 231.775 mm |
| Outer diameter D | 300.038 mm |
| Width B | 33.338 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 267 kN |
| Basic static load rating C0 | 425 kN |
| Fatigue load limit Pu | 39 kN |
| Reference speed (thermal) | 1500 rpm |
| Limiting speed (mechanical) | 1900 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 5200 g |
| Manufacturer designation | SKF 544091/544118 |
| 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 & 544000-series range
| Bore d | 9.125 in |
|---|---|
| Outer diameter D | 11.813 in |
| Width B | 1.313 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 34.1 mm |
| Smallest bore in 544000-series | 231.775 mm |
| Largest outer diameter in 544000-series | 300.038 mm |
| Width range across 544000-series | 33.338–33.338 mm |
| Bore position in 544000-series (smallest first) | 1 of 1 |
| Bore above smallest 544000-series size | 0 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 544091-544118 | 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 544091-544118 model number is decoded
Journal and housing interface: the 231.775 mm bore takes a m6 shaft seat (upper deviation ~0.464 mm for this diameter range) and the 300.038 mm outside diameter pairs with an H7 housing bore tolerance band of 300.038.000/300.058 mm; the 33.338 mm width defines the shoulder depth, and the 5200 g cone-plus-cup assembly is the dead load on the shaft during thermal expansion calculations. The cup reference 544118 is structural, not a suffix: it identifies the outer ring that, combined with the 544091 cone, produces the 231.775/300.038/33.338 mm envelope catalogue-listed as 544091. Quote the cup number in full when ordering — the 544000-series tables contain other cups that fit the same cone but change the bearing.The SKF 544091/544118 is a 231.775×300.038×33.338 mm single-row tapered roller bearing — an inch-series entry with an asymmetric raceway cut for thrust capacity and separable mounting.Numbering ties the bearing to its inch-series envelope: 544091 means a cone and cup matched pair in the 544000-series series — which is why the 231.775×300.038×33.338 mm outline swaps dimensionally with other inch-series bearings of the same code. SKF lists the plain number as the basic execution; letter suffixes such as B denote a steeper contact angle and are different order numbers. The 34.1 mm radial section height ((300.038−231.775)/2) and 5200 g catalogue mass frame a 231.775 mm bore bearing rated at 267 kN C — roughly 1.15 kN of dynamic capacity per millimetre of bore before application factors. A single 544091 locates the shaft in one axial direction only; mount it against a second bearing in O (back-to-back) or X (face-to-face) arrangement, and set the running clearance by the mounting procedure — not by feel.
Typical equipment & failure modes
Common applications
- large industrial mixer shafts
- offshore winch and drawworks drums
- rolling-mill roll-neck bearings
- heavy-duty rolling-mill 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
- thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting
- thermal preload runaway in an O-arrangement pair when inner-ring heat expands the setting
- cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity
- fretting corrosion on a loose rotating shaft seat
Selection pitfalls — read before you substitute
- At 231.775 mm bore the cone mass is high enough that cocking during mounting damages the cage and rib; guide the ring square, confirm seat contact around the full circumference, and re-check setting after the first thermal cycle of the paired set.
- The 544000-series inch series at 231.775 mm bore (300.038×33.338 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.
- Do not mix brands or executions inside one 544091 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.
- Do not mix brands or executions inside one 544091 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.
- Catalogue reference speed and limiting speed are different limits: the 1,500 r/min reference is a thermal criterion under load, while the 1,900 r/min limiting value is the mechanical ceiling — observe both.
- The 267/425 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 544091 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 544091/544118 designation when purchasing and match the execution to the mounting arrangement.
Frequently asked questions
What shaft and housing fits suit 544091?
For a rotating shaft under normal load, seat the cone on a m6 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 33.338 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 544091 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 544091?
The SKF 544091/544118 is a single-row tapered roller bearing with 231.775 mm bore, 300.038 mm outer diameter and 33.338 mm width (9.125 × 11.813 × 1.313 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 267 kN, C0 425 kN, fatigue load limit Pu 39 kN, reference speed 1,500 r/min, limiting speed 1,900 r/min, mass about 5200 g. It is an open, separable bearing with a pressed-steel cage.
How does the 544091 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 544000-series code marks the dimensional series. The metric dimensions 231.775×300.038×33.338 mm are the converted equivalents of the original inch boundary dimensions.
What do the cone and cup numbers in 544091 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 (544000-series) groups sizes that share the same boundary-dimension plan.
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.