30220T100-DB bearing: complete specifications & equivalents
The 30220T100-DB is a ISO 355 radial bearing sized 100 x 180 x 100 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 100 mm |
| Outer diameter D | 180 mm |
| Width B | 100 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 521 kN |
| Basic static load rating C0 | 640 kN |
| Fatigue load limit Pu | 72 kN |
| Reference speed (thermal) | 2400 rpm |
| Limiting speed (mechanical) | 3600 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 8850 g |
| Manufacturer designation | SKF 30220T100/DB |
| Standard | ISO 355 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants |
| Last verified | 2026-09-29 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants) · extracted 2026-09-29
Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants); 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 & matched-db-series range
| Bore d | 3.937 in |
|---|---|
| Outer diameter D | 7.087 in |
| Width B | 3.937 in |
| ISO bore code | 00 |
| Radial section height (D−d)/2 | 40 mm |
| Smallest bore in matched-db-series | 35 mm |
| Largest outer diameter in matched-db-series | 480 mm |
| Width range across matched-db-series | 41.5–288 mm |
| Bore position in matched-db-series (smallest first) | 14 of 30 |
| Bore above smallest matched-db-series size | 65 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 30220T100 | ISO 15 | full Dimensions and internal design equivalent — standard interchange. | ISO 15 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 30220T100-DB model number is decoded
Thermal behaviour of the pair: heat generated in the 100 mm bore cones flows along the shaft and changes the setting; the /DB clearance class is chosen for the catalogue speed range 2,400–3,600 r/min, so re-select the clearance class if the application runs hotter. The rotating cones of 30220T100-DB take a k5 seat on the 100 mm shaft; the cups are a transition-to-loose fit so the pair can be clamped to its factory setting during assembly.30220T100-DB is a matched pair of single-row tapered roller bearings arranged back-to-back (O) matched pair, supplied by SKF in SKF catalogue PUB BU/P1 17000 as one factory-set unit: the two bearings, spacers and setting are matched together and must not be mixed with other sets.Reading the designation: 30220T100 is the ISO 355 single-row base bearing (100 mm bore), and the suffix /DB marks the matched-set execution — arrangement, spacer grinding and factory clearance class. The pair envelope is 100×180×100 mm; the width covers both bearings of the set. In the back-to-back (O) arrangement the load lines diverge toward the shaft axis, giving the pair a wide effective spread: 30220T100-DB resists overturning moments and tilting loads stiffly, which is why O-sets are preferred for gearbox output shafts and pinion supports. Selection arithmetic: the catalogue C 521 kN and C0 640 kN are ratings of the complete pair, not of one bearing — never halve them back to a single-row figure when checking L10 life, and use the pair Pu 72 kN as the fatigue floor. Operating context for the 100 mm bore: a shaft of this diameter typically runs in the large-bore band of industrial duty, and the 180 mm OD places the housing shoulder near 188 mm outer abutment.
Typical equipment & failure modes
Common applications
- marine deck machinery shafts
- heavy industrial gearboxes and speed reducers
- large process pump and compressor shafts
- rolling-mill auxiliary drives
Known failure patterns
- 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
- cage pocket scoring when the bearing starts cold with grease of too-high base-oil viscosity
- brinelling from pressing the cone or cup home through the rollers
- rib-roller contact scoring from loss of the EP additive film
Selection pitfalls — read before you substitute
- Spacer faces must stay parallel within the set's own tolerance; a tilted spacer in 30220T100-DB concentrates reversing thrust on one bearing and shows up as one-sided raceway wear.
- Clamp the 30220T100-DB pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.
- Clamp the 30220T100-DB pair axially through the cones, never through the rollers; pressing force across the roller complement brinells the raceways of both bearings at once.
- The 521/640 kN ratings are SKF catalogue 17000 values for this 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.
- Quote the full SKF 30220T100/DB designation when purchasing — base-number-only orders are ambiguous across executions and variants.
Frequently asked questions
What are the dimensions and catalogue data of 30220T100-DB?
The SKF 30220T100/DB is a matched pair of single-row tapered roller bearings in back-to-back (O) matched pair arrangement with 100 mm bore, 180 mm outer diameter and 100 mm overall width (3.937 × 7.087 × 3.937 in). From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 521 kN, C0 640 kN, fatigue load limit Pu 72 kN, reference speed 2,400 r/min, limiting speed 3,600 r/min, mass about 8.85 kg.
What does the /DB suffix on 30220T100-DB mean?
The base 30220T100 is the ISO 355 single-row bearing; the /DB suffix marks the matched-set execution — the arrangement (back-to-back (O)), the ground spacer and the factory-set axial clearance class. A matched set cannot be assembled from loose single bearings; quote the full designation when ordering.
Are the C and C0 ratings of 30220T100-DB for one bearing or the pair?
They are for the complete matched pair: C 521 kN dynamic and C0 640 kN static already include load sharing between the two bearings. Do not halve them for single-bearing checks, and do not compare them directly with the single-row 30220T100 table values.
Can 30220T100-DB be adjusted like two loose tapered bearings?
No — the axial clearance is set at the factory by selective spacer grinding. Mounting work is limited to clean seats, correct fits (k5 on a rotating 100 mm shaft) and axial clamping through the cones; re-setting in the field destroys the matched clearance class.
When should a back-to-back (O) matched set be chosen?
Choose the back-to-back (O) set where moment stiffness dominates — pinion supports, gearbox output shafts, crane sheaves. The diverging load lines give the widest effective spread at the 100 mm bore.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 8.3-8.8 TRB variants on 2026-09-29. Read our editorial & correction policy.