29348 bearing: complete specifications & equivalents
The 29348 is a ISO 104 radial bearing sized 240 x 380 x 85 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 | 380 mm |
| Width B | 85 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 1530 kN |
| Basic static load rating C0 | 5250 kN |
| Fatigue load limit Pu | 390 kN |
| Limiting speed (mechanical) | 910 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 36600 g |
| Manufacturer designation | NTN 29348 |
| 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 & 29300-series range
| Bore d | 9.449 in |
|---|---|
| Outer diameter D | 14.961 in |
| Width B | 3.346 in |
| ISO bore code | 48 |
| Radial section height (D−d)/2 | 70 mm |
| Smallest bore in 29300-series | 85 mm |
| Largest outer diameter in 29300-series | 1180 mm |
| Width range across 29300-series | 39–230 mm |
| Bore position in 29300-series (smallest first) | 15 of 31 |
| Bore above smallest 29300-series size | 155 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 29348-E | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 240×380×85 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 29348 model number is decoded
The medium-section 29300 spherical-thrust family entry 29348 combines a spherical housing-washer raceway with asymmetric barrel rollers in 85 mm of stack height. The designation is 293 is the dimension series (medium-section 29300 spherical-thrust family) plus 48 encodes the 240 mm bore (bore code x 5). Catalogue axial dynamic rating Ca is 1530 kN against C0a 5250 kN — the roller contact line is why a 240 mm bore here out-carries any thrust ball bearing of the same size. Where the shaft also needs radial location, pair this bearing with a spherical roller or cylindrical radial bearing — the thrust bearing is not a radial guide. Torque the shaft nut against the shaft washer shoulder and verify axial clamping — a loose shaft washer frets the seat under 1530 kN class thrust.
Typical equipment & failure modes
Common applications
- large marine propulsion thrust supports
- crane and excavator main slew bearings duty
- rotary kiln and furnace thrust positions
- large vertical mill and crusher main shafts
Known failure patterns
- edge stress and raceway flaking after the housing was machined so far out that the self-aligning travel ran out — alignment compensation is limited, not infinite
- oil-starvation polishing and then seizure of the cage guide bush when the bath level dropped below the cage
- 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
- contamination denting from wear particles circulating in the oil bath — the dents seed the next round of surface fatigue
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 293 medium section is the workhorse: balanced height and capacity for general heavy thrust duty at 240 mm bore.
- The 85 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.
- A spherical roller thrust bearing cannot take radial misalignment of the seats beyond its aligning travel — verify the housing geometry before blaming the bearing.
- Below the minimum axial load the rollers skid; at 910 r/min the Ca of 1530 kN never comes into play before the raceway is smeared.
- The Ca 1530/C0a 5250 kN ratings and 390 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 29348; 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 29348?
29348 is a spherical roller thrust bearing to ISO 104: 240 mm shaft-washer bore, 380 mm outside diameter, 85 mm stack height (9.449 x 14.961 x 3.346 in). From NTN Ball and Roller Bearings CAT.No.2203E: axial Ca 1530 kN, C0a 5250 kN and a 390 kN fatigue load limit Pu; limiting speed 910 r/min with oil lubrication; mass about 36600 g.
How is the 29348 designation structured?
293 is the dimension series (medium-section 29300 spherical-thrust family); 48 encodes the 240 mm bore (bore code x 5). The 380 mm OD and 85 mm height follow the ISO 104 boundary plan for that series.
Can 29348 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, 910 r/min, for 29348?
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 29348?
The 240/380/85 mm envelope is ISO 104 interchangeable, but roller profile, osculation, cage and washer details are maker-specific. Re-verify Ca 1530 kN / C0a 5250 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.