29420 bearing: complete specifications & equivalents
The 29420 is a ISO 104 radial bearing sized 100 x 210 x 67 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 100 mm |
| Outer diameter D | 210 mm |
| Width B | 67 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 760 kN |
| Basic static load rating C0 | 2130 kN |
| Fatigue load limit Pu | 156 kN |
| Limiting speed (mechanical) | 1500 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 11500 g |
| Manufacturer designation | NTN 29420 |
| Standard | ISO 104 |
| Catalog version | NTN Ball and Roller Bearings CAT.No.2203E |
| Last verified | 2026-10-01 |
Source: catalog reference (NTN Ball and Roller Bearings CAT.No.2203E) · extracted 2026-10-01
Parameters extracted from the official NTN Ball and Roller Bearings catalogue (NTN Ball and Roller Bearings CAT.No.2203E); NTN® is a trademark of NTN Corporation, used here for identification only — mpnbase is not an authorized NTN distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at ntnglobal.com.
Dimensions in inches & 29400-series range
| Bore d | 3.937 in |
|---|---|
| Outer diameter D | 8.268 in |
| Width B | 2.638 in |
| ISO bore code | 20 |
| Radial section height (D−d)/2 | 55 mm |
| Smallest bore in 29400-series | 60 mm |
| Largest outer diameter in 29400-series | 1770 mm |
| Width range across 29400-series | 42–426 mm |
| Bore position in 29400-series (smallest first) | 8 of 46 |
| Bore above smallest 29400-series size | 40 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 29420-E | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 100×210×67 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting. |
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 29420 model number is decoded
29420 is the 100 mm member of NTN's heavy-section 29400 spherical-thrust family: 210 mm over the housing washer, 67 mm tall. Two fields make up the code — 294 is the dimension series (heavy-section 29400 spherical-thrust family) and 20 encodes the 100 mm bore (bore code x 5). A machined cage guided on the shaft-washer sleeve keeps the roller set spaced at the 1,500 r/min oil rating. Within the spherical-thrust plan, 292 is the light section and 294 the heavy one; stepping up from a 292 to a 294 at the same bore roughly doubles the C0a class. Lift the bearing by the washers, never through the roller set; a 12 kg stack punishes improvisation.
Typical equipment & failure modes
Common applications
- pellet-mill and grinder main-shaft thrust seats
- ship propulsion and rudder thrust blocks
- large mixer, reactor and agitator vertical shafts
- bulk-handler stacker/reclaimer slew pivots
Known failure patterns
- cage and roller-end scoring when the shaft was forced into alignment by the bearing itself during a bent-shaft rescue
- roller/raceway scuffing from an interrupted oil supply — at these loads the EHL film is the only thing between rolling and smearing
- roller skid smearing when axial load fell below the minimum while the shaft was still turning fast
- fatigue spalling on the shaft-washer raceway beginning at the high-stress inner end of the roller contact
- thermal distress when oil viscosity was chosen by habit instead of the operating-temperature calculation
Selection pitfalls — read before you substitute
- Bearings of 100 mm bore need planned lifting and heating; a shaft washer driven on cold and crooked starts the failure clock before the first load.
- The 294 heavy section tops the plan at this bore with the largest 210 mm OD and tallest stack — confirm housing space and oil capacity before upgrading a 293 position.
- The 67 mm stack height is part of the load path — any spacer or shim stack added under the housing washer must carry the full thrust without settling.
- Mixing washers between bearings during overhaul is a real risk at this size — rollers and raceways run in together, so keep each 29420 stack as a set.
- Oil is not optional at this rating: the 1,500 r/min figure assumes oil lubrication, and a grease conversion is a redesign, not a fill change.
- The Ca 760/C0a 2130 kN ratings and 156 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 29420; roller profile and osculation legitimately differ between manufacturers, so re-verify ratings, oil supply and minimum load before substituting another make.
Frequently asked questions
What are the dimensions and catalogue ratings of NTN 29420?
29420 is a spherical roller thrust bearing to ISO 104: 100 mm shaft-washer bore, 210 mm outside diameter, 67 mm stack height (3.937 x 8.268 x 2.638 in). From NTN Ball and Roller Bearings CAT.No.2203E: axial Ca 760 kN, C0a 2130 kN and a 156 kN fatigue load limit Pu; limiting speed 1,500 r/min with oil lubrication; mass about 11500 g.
How is the 29420 designation structured?
294 is the dimension series (heavy-section 29400 spherical-thrust family); 20 encodes the 100 mm bore (bore code x 5). The 210 mm OD and 67 mm height follow the ISO 104 boundary plan for that series.
Can 29420 handle misalignment and radial load?
Yes to both, with limits. The spherical housing-washer raceway lets the bearing self-align against steady seat misalignment, and the angled roller contact tolerates a radial share while axial load clearly dominates. It is not a radial bearing: shaft radial location still needs its own radial bearing.
Why does NTN print only an oil speed, 1,500 r/min, for 29420?
Spherical roller thrust bearings of this size work under contact stresses that need an elastohydrodynamic oil film; grease is reserved for the smallest, slowest duties. The printed figure is the limiting speed with the catalogue oil-lubrication state — bath level, viscosity and cooling decide how close a real installation may run.
What should be checked before substituting another make for 29420?
The 100/210/67 mm envelope is ISO 104 interchangeable, but roller profile, osculation, cage and washer details are maker-specific. Re-verify Ca 760 kN / C0a 2130 kN, the oil speed rating and the minimum-load requirement against the donor catalogue before swapping on a rated drive.
Reviewed & verified by the MPN Base engineering desk against source catalog NTN Ball and Roller Bearings CAT.No.2203E on 2026-10-01. Read our editorial & correction policy.