32021 bearing: complete specifications & equivalents
The 32021 is a ISO 355 radial bearing sized 105 x 160 x 35 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | FAG |
| Bore diameter d | 105 mm |
| Outer diameter D | 160 mm |
| Width B | 35 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 238 kN |
| Basic static load rating C0 | 330 kN |
| Fatigue load limit Pu | 51 kN |
| Reference speed (thermal) | 2800 rpm |
| Limiting speed (mechanical) | 5100 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 2440 g |
| Manufacturer designation | 32021-X-XL |
| Standard | ISO 355 |
| Catalog version | Schaeffler HR1 (2022 ed.), Tapered roller bearings DIN/ISO 355 |
| Last verified | 2026-09-26 |
Source: catalog reference (Schaeffler HR1 (2022 ed.), Tapered roller bearings DIN/ISO 355) · extracted 2026-09-26
Parameters extracted from the official FAG Rolling Bearings catalogue (Schaeffler HR1 (2022 ed.), Tapered roller bearings DIN/ISO 355); FAG® is a trademark of Schaeffler Technologies AG & Co. KG, used here for identification only — mpnbase is not an authorized FAG/Schaeffler distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at schaeffler.com.
Dimensions in inches & 32000-series range
| Bore d | 4.134 in |
|---|---|
| Outer diameter D | 6.299 in |
| Width B | 1.378 in |
| ISO bore code | 21 |
| Radial section height (D−d)/2 | 27.5 mm |
| Smallest bore in 32000-series | 20 mm |
| Largest outer diameter in 32000-series | 650 mm |
| Width range across 32000-series | 15–130 mm |
| Bore position in 32000-series (smallest first) | 21 of 43 |
| Bore above smallest 32000-series size | 85 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 32021 | ISO 15 | full Dimensions and internal design equivalent — standard interchange. | ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier. |
| 32021-SKF | SKF | full Dimensions and internal design equivalent — standard interchange. | Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier. |
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 32021 model number is decoded
Ordering number 32021-X-XL in Schaeffler HR1 (2022 edition) denotes a single-row tapered roller bearing for a 105 mm shaft, low-friction section, with an open pressed-steel-cage execution and one-direction axial capacity.The code breaks down as type prefix 3 (tapered roller), series 2 (the low-friction section), and bore code 21 = 105 mm; dimensions 105×160×35 mm therefore match the ISO 355 envelope. In Schaeffler notation 32021-X-XL is the basic X-life execution; B-suffix variants have a steeper contact angle and are not interchangeable with the base bearing. Catalogue mass 2440 g for the 105×160×35 mm open execution covers the pressed-steel cage and standard roller complement; sealed or special-clearance variants differ slightly in mass and carry their own order numbers. For a 105 mm shaft the usual cone seat is m6 with an H7 housing when the inner ring rotates; arrange two 32021 bearings as a set for two-direction location and set clearance from the load diagram, never from assembly feel.
Typical equipment & failure modes
Common applications
- paper-machine and printing rolls
- construction machinery drives
- marine deck machinery shafts
- heavy industrial gearboxes and speed reducers
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
- 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
- edge loading from shaft deflection or housing misalignment
Selection pitfalls — read before you substitute
- Mount the 105 mm bore 32021 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 320 series at 105 mm bore (160×35 mm) is the low-friction, higher-speed section; it carries less thrust than a 30221 of the same bore, so verify the axial load share before swapping.
- O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 32021 mounting error.
- O (back-to-back) pairs are stiffer against moments, X (face-to-face) pairs tolerate misalignment and thermal growth better; choosing the arrangement from the 2D drawing rather than the actual shaft thermal expansion is a common 32021 mounting error.
- Shaft and housing fillets must clear the bearing chamfer so the 35 mm-wide cup seats square; use an undercut or withdrawal groove rather than an oversized radius that locks on the ring face.
- The 238/330 kN ratings are Schaeffler HR1 values for the X-life execution; the -XL suffix denotes the premium grade and is part of the order designation, so quote it in full when purchasing.
- Schaeffler lists 32021 in the X-life basic execution; variant executions with -B or other suffixes are separate order numbers and are not interchangeable with the basic X-life bearing.
Frequently asked questions
What are the dimensions and catalogue data of 32021?
The 32021-X-XL is a single-row tapered roller bearing with 105 mm bore, 160 mm outer diameter and 35 mm width (4.134 × 6.299 × 1.378 in) per ISO 355. From Schaeffler HR1 (2022 edition): basic dynamic load rating C 238 kN, C0 330 kN, fatigue load limit Pu 51 kN, reference speed 2,800 r/min, limiting speed 5,100 r/min, mass about 2440 g. It is an open, separable bearing with a pressed-steel cage.
How does the 32021 bore code work?
The last two digits of 32021 are bore code 21, so 21 × 5 = 105 mm bore. The 160 mm OD and 35 mm width come from the ISO 355 dimension-series plan, shared with other tapered bearings of the same code.
What do the 32021 series and X-life execution designations mean?
The leading 3 marks a single-row tapered roller bearing; the second digit 2 is the ISO 355 series (low-friction section). The FAG -XL suffix denotes X-life premium grade; the ISO 355 series code is interchangeable with other brands. A steeper-contact-angle variant (B suffix) is a different order number and is not interchangeable with the basic execution.
Can a single 32021 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 32021 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 32021 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 Schaeffler HR1 (2022 ed.), Tapered roller bearings DIN/ISO 355 on 2026-09-26. Read our editorial & correction policy.