29334 bearing: complete specifications & equivalents
The 29334 is a ISO 104 radial bearing sized 170 x 280 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 | 170 mm |
| Outer diameter D | 280 mm |
| Width B | 67 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 950 kN |
| Basic static load rating C0 | 3050 kN |
| Fatigue load limit Pu | 238 kN |
| Limiting speed (mechanical) | 1200 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 16600 g |
| Manufacturer designation | NTN 29334 |
| 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 | 6.693 in |
|---|---|
| Outer diameter D | 11.024 in |
| Width B | 2.638 in |
| ISO bore code | 34 |
| Radial section height (D−d)/2 | 55 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) | 10 of 31 |
| Bore above smallest 29300-series size | 85 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 29334-E | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 170×280×67 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 29334 model number is decoded
The medium-section 29300 spherical-thrust family entry 29334 combines a spherical housing-washer raceway with asymmetric barrel rollers in 67 mm of stack height. NTN builds the number from 293 is the dimension series (medium-section 29300 spherical-thrust family); 34 encodes the 170 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 3050 kN static rating honest in real housings. Selection starts from the load case: axial must dominate, and any radial share must stay within the catalogue combined-load rule while the bearing self-aligns. On vertical shafts, confirm the minimum axial load from the rotor weight plus any spring preload before the first run at speed.
Typical equipment & failure modes
Common applications
- vertical hydro and pump-turbine main thrust blocks
- heavy rolling-mill and forging-press thrust seats
- large marine propulsion thrust supports
- crane and excavator main slew bearings duty
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
- fatigue spalling on the shaft-washer raceway beginning at the high-stress inner end of the roller contact
Selection pitfalls — read before you substitute
- At 170 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 170 mm bore.
- Below the minimum axial load the rollers skid; at 1,200 r/min the Ca of 950 kN never comes into play before the raceway is smeared.
- Oil-bath level is set for the cage, not the housing: too low starves the contact, too high churns heat at the 1,200 r/min end of the range.
- Do not let the self-aligning travel absorb a bent shaft: the bearing aligns to seats, not to a shaft that whips.
- The Ca 950/C0a 3050 kN ratings and 238 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 29334; 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 29334?
29334 is a spherical roller thrust bearing to ISO 104: 170 mm shaft-washer bore, 280 mm outside diameter, 67 mm stack height (6.693 x 11.024 x 2.638 in). From NTN Ball and Roller Bearings CAT.No.2203E: axial Ca 950 kN, C0a 3050 kN and a 238 kN fatigue load limit Pu; limiting speed 1,200 r/min with oil lubrication; mass about 16600 g.
How is the 29334 designation structured?
293 is the dimension series (medium-section 29300 spherical-thrust family); 34 encodes the 170 mm bore (bore code x 5). The 280 mm OD and 67 mm height follow the ISO 104 boundary plan for that series.
Can 29334 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, 1,200 r/min, for 29334?
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 29334?
The 170/280/67 mm envelope is ISO 104 interchangeable, but roller profile, osculation, cage and washer details are maker-specific. Re-verify Ca 950 kN / C0a 3050 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.