29418 bearing: complete specifications & equivalents
The 29418 is a ISO 104 radial bearing sized 90 x 190 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 | 90 mm |
| Outer diameter D | 190 mm |
| Width B | 60 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 610 kN |
| Basic static load rating C0 | 1680 kN |
| Fatigue load limit Pu | 121 kN |
| Limiting speed (mechanical) | 1700 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 8380 g |
| Manufacturer designation | NTN 29418 |
| 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 | 3.543 in |
|---|---|
| Outer diameter D | 7.48 in |
| Width B | 2.362 in |
| ISO bore code | 18 |
| Radial section height (D−d)/2 | 50 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) | 7 of 46 |
| Bore above smallest 29400-series size | 30 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 29418-E | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 90×190×60 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 29418 model number is decoded
The heavy-section 29400 spherical-thrust family entry 29418 combines a spherical housing-washer raceway with asymmetric barrel rollers in 60 mm of stack height. Decoding 29418: 294 is the dimension series (heavy-section 29400 spherical-thrust family), with 18 encodes the 90 mm bore (bore code x 5). The static/dynamic ratio of 2.75 tells the story of a roller raceway: enormous reserve for slow, shocked or oscillating thrust. 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 610 kN class thrust.
Typical equipment & failure modes
Common applications
- ship propulsion and rudder thrust blocks
- large mixer, reactor and agitator vertical shafts
- bulk-handler stacker/reclaimer slew pivots
- vertical hydro-turbine and large pump 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
- fretting on the shaft seat after the washer crept under reversing axial shock
- cage-pocket wear after long service with vibration at standstill, the rollers hammering the pocket surfaces
Selection pitfalls — read before you substitute
- Bearings of 90 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 190 mm OD and tallest stack — confirm housing space and oil capacity before upgrading a 293 position.
- Do not let the self-aligning travel absorb a bent shaft: the bearing aligns to seats, not to a shaft that whips.
- The C0a of 1680 kN is a static rating — sizing continuous thrust from C0a alone overstates the raceway's life.
- A spherical roller thrust bearing cannot take radial misalignment of the seats beyond its aligning travel — verify the housing geometry before blaming the bearing.
- The Ca 610/C0a 1680 kN ratings and 121 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 29418; 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 29418?
29418 is a spherical roller thrust bearing to ISO 104: 90 mm shaft-washer bore, 190 mm outside diameter, 60 mm stack height (3.543 x 7.48 x 2.362 in). From NTN Ball and Roller Bearings CAT.No.2203E: axial Ca 610 kN, C0a 1680 kN and a 121 kN fatigue load limit Pu; limiting speed 1,700 r/min with oil lubrication; mass about 8380 g.
How is the 29418 designation structured?
294 is the dimension series (heavy-section 29400 spherical-thrust family); 18 encodes the 90 mm bore (bore code x 5). The 190 mm OD and 60 mm height follow the ISO 104 boundary plan for that series.
Can 29418 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, 1,700 r/min, for 29418?
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 29418?
The 90/190/60 mm envelope is ISO 104 interchangeable, but roller profile, osculation, cage and washer details are maker-specific. Re-verify Ca 610 kN / C0a 1680 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.