32228 bearing: complete specifications & equivalents

The 32228 is a ISO 355 radial bearing sized 140 x 250 x 71.75 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.

Bearing dimension schematic Front view shows outer diameter D and bore d; side section shows width B. D = 250 mm d = 140 B = 71.75 mm side section front view
Principal dimensions: bore d 140 mm, outer diameter D 250 mm, width B 71.75 mm. Schematic, not to scale.

Specification table

ParameterValue
Brand SKF
Bore diameter d 140 mm
Outer diameter D 250 mm
Width B 71.75 mm
Material GCr15
Seal / shield open
Internal clearance CN
Tolerance class P0
Cage steel, stamped ribbon (J-type)
Basic dynamic load rating C 691 kN
Basic static load rating C0 1000 kN
Fatigue load limit Pu 100 kN
Reference speed (thermal) 1900 rpm
Limiting speed (mechanical) 2600 rpm
Operating temperature -40 to +120 °C
Mass 14000 g
Manufacturer designation SKF 32228
Standard ISO 355
Catalog version SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB
Last verified 2026-09-28

Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric 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. 8.1 metric 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 & 32200-series range

Bore d 5.512 in
Outer diameter D 9.843 in
Width B 2.825 in
ISO bore code 28
Radial section height (D−d)/2 55 mm
Smallest bore in 32200-series 17 mm
Largest outer diameter in 32200-series 580 mm
Width range across 32200-series 17.25–159 mm
Bore position in 32200-series (smallest first) 24 of 36
Bore above smallest 32200-series size 123 mm

Cross references & equivalents

Equivalent modelBrandMatch levelNote
32228 ISO 15 full
Dimensions and internal design equivalent — standard interchange.
ISO 355 boundary-dimension envelope; brand-specific OEM equivalents (NSK/FAG/NTN) pending multi-source data.

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 32228 model number is decoded

SKF 32228 belongs to the SKF single-row tapered roller range — the 140 mm bore entry in the 32200 series, dimensioned 250 mm OD and 71.75 mm wide to the ISO 355 boundary plan.The code breaks down as type prefix 3 (tapered roller), series 22 (the heavy section), and bore code 28 = 140 mm; dimensions 140×250×71.75 mm therefore match the ISO 355 envelope. In SKF suffix language a bare 32228 is the standard execution; B marks a larger contact angle and Q or J2 mark clearance/cage variants, all quoted separately. The 55.0 mm radial section height ((250−140)/2) and 14000 g catalogue mass frame a 140 mm bore bearing rated at 691 kN C — roughly 4.94 kN of dynamic capacity per millimetre of bore before application factors. For a 140 mm shaft the usual cone seat is m6 with an H7 housing when the inner ring rotates; arrange two 32228 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel. Dimensional interchange map: within the 32200 series at 140 mm bore, the 250 mm OD and 71.75 mm width are fixed by the ISO 355 plan, so any same-code bearing from another brand shares the mounting envelope; the 55.0 mm section height distinguishes this family from a 302 or 322 of the same bore, and the 14000 g mass is the minimum—sealed or snap-ring executions add rotating weight above that catalogue baseline.

Typical equipment & failure modes

Common applications

  • wind-turbine main shafts
  • marine propulsion gearboxes
  • large industrial mixer shafts
  • offshore winch and drawworks drums

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
  • 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
  • rib-roller contact scoring from loss of the EP additive film

Selection pitfalls — read before you substitute

  • At 140 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 322 series at 140 mm bore (250×71.75 mm) is a wider, higher-capacity section than 30228; do not substitute without re-checking shaft shoulder diameters and pair setting.
  • The tapered contact angle creates an induced axial load under pure radial force; include it in the 32228 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 32228 pair raises operating temperature and can trigger thermal runaway, while too little lets the rollers skid and smear the raceway under light load.
  • Open 32228 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 691/1000 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 32228 (basic, B steeper angle, Q/J2 clearance variants); they are not interchangeable order numbers — quote the full SKF 32228 designation when purchasing and match the execution to the mounting arrangement.

Frequently asked questions

What are the dimensions and catalogue data of 32228?

The SKF 32228 is a single-row tapered roller bearing with 140 mm bore, 250 mm outer diameter and 71.75 mm width (5.512 × 9.843 × 2.825 in) per ISO 355. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 691 kN, C0 1000 kN, fatigue load limit Pu 100 kN, reference speed 1,900 r/min, limiting speed 2,600 r/min, mass about 14000 g. It is an open, separable bearing with a pressed-steel cage.

How does the 32228 bore code work?

The last two digits of 32228 are bore code 28, so 28 × 5 = 140 mm bore. The 250 mm OD and 71.75 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code.

What do the 32228 series and basic execution designations mean?

The leading 3 marks a single-row tapered roller bearing; the second digit 22 is the ISO 355 series (heavy section). The SKF catalogue lists the ISO 355 dimension-series code after the bare number. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution.

Can a single 32228 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 32228 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 32228 position and vice versa — verify load direction, Fa/Fr ratio and speed before substituting.

Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.1 metric single-row TRB on 2026-09-28. Read our editorial & correction policy.