29248-NTN bearing: complete specifications & equivalents
The 29248-NTN is a ISO 104 radial bearing sized 240 x 340 x 60 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 240 mm |
| Outer diameter D | 340 mm |
| Width B | 60 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 890 kN |
| Basic static load rating C0 | 3600 kN |
| Fatigue load limit Pu | 271 kN |
| Limiting speed (mechanical) | 1100 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 17500 g |
| Manufacturer designation | NTN 29248 |
| 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 & 29200-series range
| Bore d | 9.449 in |
|---|---|
| Outer diameter D | 13.386 in |
| Width B | 2.362 in |
| ISO bore code | 48 |
| Radial section height (D−d)/2 | 50 mm |
| Smallest bore in 29200-series | 150 mm |
| Largest outer diameter in 29200-series | 1060 mm |
| Width range across 29200-series | 39–155 mm |
| Bore position in 29200-series (smallest first) | 8 of 26 |
| Bore above smallest 29200-series size | 90 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 29248 | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 240×340×60 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 29248-NTN model number is decoded
At 240 x 340 x 60 mm, NTN 29248 sits in the light-section 29200 spherical-thrust family of the spherical-thrust programme. Reading the code: 292 is the dimension series (light-section 29200 spherical-thrust family), and 48 encodes the 240 mm bore (bore code x 5). At 60 mm of height the bearing packs the light-section capacity into a stack far shorter than a comparable multi-row ball arrangement. If speed climbs toward the 1,100 r/min oil rating, the lubrication design — bath, circulation, cooling — becomes the real selection criterion. The 240 mm shaft washer normally mounts with a tight shaft fit; support the housing washer so it stays free to align on its spherical seat.
Typical equipment & failure modes
Common applications
- heavy rolling-mill and forging-press thrust seats
- large marine propulsion thrust supports
- crane and excavator main slew bearings duty
- rotary kiln and furnace thrust positions
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
- flaking that started where radial load share grew past the design assumption — the bearing tolerates combined load only while axial load clearly dominates
- contamination denting from wear particles circulating in the oil bath — the dents seed the next round of surface fatigue
- fretting on the shaft seat after the washer crept under reversing axial shock
Selection pitfalls — read before you substitute
- At 240 mm bore, seating geometry, oil supply and the minimum-load guarantee decide life — field improvisation on any of the three is the usual root cause.
- The 292 light section is the speed-and-space end of the spherical-thrust plan — for the same 240 mm bore it trades capacity for a smaller 340 mm OD and lower height.
- Shock thrust above C0a 3600 kN leaves contact dents that seed fatigue; screwdown and press duties need the static check first.
- Below the minimum axial load the rollers skid; at 1,100 r/min the Ca of 890 kN never comes into play before the raceway is smeared.
- Axial load must dominate; letting the radial share creep up because the radial bearing wore is the quiet path to early raceway flaking.
- The Ca 890/C0a 3600 kN ratings and 271 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 29248; 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 29248?
29248 is a spherical roller thrust bearing to ISO 104: 240 mm shaft-washer bore, 340 mm outside diameter, 60 mm stack height (9.449 x 13.386 x 2.362 in). From NTN Ball and Roller Bearings CAT.No.2203E: axial Ca 890 kN, C0a 3600 kN and a 271 kN fatigue load limit Pu; limiting speed 1,100 r/min with oil lubrication; mass about 17500 g.
How is the 29248 designation structured?
292 is the dimension series (light-section 29200 spherical-thrust family); 48 encodes the 240 mm bore (bore code x 5). The 340 mm OD and 60 mm height follow the ISO 104 boundary plan for that series.
Can 29248 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, 1,100 r/min, for 29248?
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 29248?
The 240/340/60 mm envelope is ISO 104 interchangeable, but roller profile, osculation, cage and washer details are maker-specific. Re-verify Ca 890 kN / C0a 3600 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.