29318-E bearing: complete specifications & equivalents
The 29318-E is a ISO 104 radial bearing sized 90 x 155 x 39 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 90 mm |
| Outer diameter D | 155 mm |
| Width B | 39 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 400 kN |
| Basic static load rating C0 | 1080 kN |
| Fatigue load limit Pu | 132 kN |
| Reference speed (thermal) | 2400 rpm |
| Limiting speed (mechanical) | 4000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 2850 g |
| Manufacturer designation | 29318 E |
| Standard | ISO 104 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 13.1 spherical roller thrust bearings |
| Last verified | 2026-09-27 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 13.1 spherical roller thrust bearings) · extracted 2026-09-27
Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 13.1 spherical roller thrust bearings); SKF® and SKF Explorer® are trademarks of AB SKF, used here for identification only — mpnbase is not an authorized SKF distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at skf.com.
Dimensions in inches & 29300-series range
| Bore d | 3.543 in |
|---|---|
| Outer diameter D | 6.102 in |
| Width B | 1.535 in |
| ISO bore code | 18 |
| Radial section height (D−d)/2 | 32.5 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) | 2 of 31 |
| Bore above smallest 29300-series size | 5 mm |
Cross references & equivalents
No verified interchange data yet. Send an inquiry and our team will confirm equivalents manually.
How the 29318-E model number is decoded
Where a cylindrical roller thrust bearing would edge-load under deflection, 29318 E aligns itself: 90×155×39 mm envelope, 1080 kN static rating, one load direction. SKF suffixes on spherical roller thrust bearings describe cages: E the standard stamped steel window cage, EM the machined brass execution, EF the extra-large steel-cage design; 29318 E is the stamped steel E window cage. A minimum axial load of factor A 0.11 must be maintained — in the large 293 sizes this is a real force (often supplied by springs, oil pressure or the rotor weight), below it the rollers skid and smear. One direction only: 29318 E cannot be reversed to take opposite thrust — mirror a second bearing for reversing shafts, and keep housing and shaft seats square within the ISO 104 tolerances. Mounting: fit the shaft washer tight on the 90 mm seat, seat the sphered housing washer on its matching (often separately supplied) seating washer, and check the assembly swivels freely before applying the 400 kN working load.
Typical equipment & failure modes
Common applications
- paper machine calender and refiner discs with combined axial and radial force
- crane hook assemblies where the hook block turns under full load
- injection moulding machine and extruder screw thrust positions
- vertical hydro generators and large vertical pump motors
Known failure patterns
- roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)
- washer back-face fretting where the seat is too narrow to support the full ring face
- grease churning and overheating when a high-speed thrust position is over-packed
- rolling-contact fatigue spalling after the catalogue L10 life is exhausted
- smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established
Selection pitfalls — read before you substitute
- At 90 mm bore the 293 bearing already weighs 2.9 kg and sits 39 mm high — check the hook-nut thread and seat square-ness before trusting it with a lifted load.
- Radial force beyond the permitted fraction of simultaneous thrust (about 0.55·F_a) overloads one side of the barrel-roller set — add a radial bearing instead of leaning on 29318 E.
- E, EM and EF suffixes are cage designs for different size bands, not quality grades: substitute only within the same envelope and check the lubricant compatibility of the cage material.
- The 400/1080 kN figures assume the matching sphered seating washer is fitted where the catalogue calls for it; a flat housing seat removes the self-aligning function.
- Minimum load factor A 0.11 dominates commissioning: start the oil flow and preload before rotation, especially on 293 bearings where an unloaded cold start smears the rollers.
- The 400/1080 kN ratings and 2850 g mass are SKF catalogue values transcribed from ch. 13.1 of PUB BU/P1 17000 (PDF table page 924); mounting data — the minimum axial load factor A — appears in the running text because the structured record carries the boundary envelope only.
Frequently asked questions
What do E, EM and EF mean on 29318 E?
They are cage designs for different size bands: E is the stamped steel window cage of the current design, EM the machined brass cage for heavy/slow sizes, EF the steel cage for extra-large bearings — not quality grades. This bearing carries the stamped steel E window cage.
Where is the 29318 E typically used?
Crane hook blocks, extruder and injection-moulding screws, vertical hydro generators, large gearbox thrust positions and heavy mill shafts — places with very high one-direction axial load plus shaft deflection.
What destroys a spherical roller thrust bearing?
Unloaded rotation below A 0.11 (roller smearing), interrupted oil supply on the large sizes, a missing sphered seating washer that removes alignment, and contamination. Limiting speed here is 4,000 r/min.
Which dimensions does the 29318 E have?
A 29318 E measures 90 mm bore × 155 mm outside diameter × 39 mm width (3.543 × 6.102 × 1.535 in). From SKF catalogue PUB BU/P1 17000: dynamic C 400 kN, static C0 1080 kN, fatigue limit Pu 132 kN, reference speed 2,400 r/min, limiting speed 4,000 r/min, mass about 2850 g. Minimum axial load factor A 0.11 must be maintained in service.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 13.1 spherical roller thrust bearings on 2026-09-27. Read our editorial & correction policy.