29438 bearing: complete specifications & equivalents
The 29438 is a ISO 104 radial bearing sized 190 x 380 x 115 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 190 mm |
| Outer diameter D | 380 mm |
| Width B | 115 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 2230 kN |
| Basic static load rating C0 | 6800 kN |
| Fatigue load limit Pu | 430 kN |
| Limiting speed (mechanical) | 840 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 62000 g |
| Manufacturer designation | NTN 29438 |
| 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 | 7.48 in |
|---|---|
| Outer diameter D | 14.961 in |
| Width B | 4.528 in |
| ISO bore code | 38 |
| Radial section height (D−d)/2 | 95 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) | 17 of 46 |
| Bore above smallest 29400-series size | 130 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 29438-E | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 190×380×115 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 29438 model number is decoded
NTN 29438 belongs to the heavy-section 29400 spherical-thrust family of spherical roller thrust bearings: 190 / 380 / 115 mm (bore / OD / height). Two fields make up the code — 294 is the dimension series (heavy-section 29400 spherical-thrust family) and 38 encodes the 190 mm bore (bore code x 5). The spherical housing raceway lets the shaft washer align itself as the seats settle — the property that keeps the 6800 kN static rating honest in real housings. If speed climbs toward the 840 r/min oil rating, the lubrication design — bath, circulation, cooling — becomes the real selection criterion. Lift the bearing by the washers, never through the roller set; a 62 kg stack punishes improvisation.
Typical equipment & failure modes
Common applications
- heavy stacker/reclaimer and shiploading pivots
- vertical hydro and pump-turbine main thrust blocks
- heavy rolling-mill and forging-press thrust seats
- large marine propulsion thrust supports
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
- 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
- thermal distress when oil viscosity was chosen by habit instead of the operating-temperature calculation
Selection pitfalls — read before you substitute
- At 190 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 294 heavy section tops the plan at this bore with the largest 380 mm OD and tallest stack — confirm housing space and oil capacity before upgrading a 293 position.
- A spherical roller thrust bearing cannot take radial misalignment of the seats beyond its aligning travel — verify the housing geometry before blaming the bearing.
- Axial load must dominate; letting the radial share creep up because the radial bearing wore is the quiet path to early raceway flaking.
- Do not let the self-aligning travel absorb a bent shaft: the bearing aligns to seats, not to a shaft that whips.
- The Ca 2230/C0a 6800 kN ratings and 430 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 29438; 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 29438?
29438 is a spherical roller thrust bearing to ISO 104: 190 mm shaft-washer bore, 380 mm outside diameter, 115 mm stack height (7.48 x 14.961 x 4.528 in). From NTN Ball and Roller Bearings CAT.No.2203E: axial Ca 2230 kN, C0a 6800 kN and a 430 kN fatigue load limit Pu; limiting speed 840 r/min with oil lubrication; mass about 62000 g.
How is the 29438 designation structured?
294 is the dimension series (heavy-section 29400 spherical-thrust family); 38 encodes the 190 mm bore (bore code x 5). The 380 mm OD and 115 mm height follow the ISO 104 boundary plan for that series.
Can 29438 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, 840 r/min, for 29438?
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 29438?
The 190/380/115 mm envelope is ISO 104 interchangeable, but roller profile, osculation, cage and washer details are maker-specific. Re-verify Ca 2230 kN / C0a 6800 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.