29284 bearing: complete specifications & equivalents
The 29284 is a ISO 104 radial bearing sized 420 x 580 x 95 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 420 mm |
| Outer diameter D | 580 mm |
| Width B | 95 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 1990 kN |
| Basic static load rating C0 | 9800 kN |
| Fatigue load limit Pu | 815 kN |
| Reference speed (thermal) | 630 rpm |
| Limiting speed (mechanical) | 1000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 75500 g |
| Manufacturer designation | 29284 |
| 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 & 29200-series range
| Bore d | 16.535 in |
|---|---|
| Outer diameter D | 22.835 in |
| Width B | 3.74 in |
| ISO bore code | 84 |
| Radial section height (D−d)/2 | 80 mm |
| Smallest bore in 29200-series | 150 mm |
| Largest outer diameter in 29200-series | 1060 mm |
| Width range across 29200-series | 39–155 mm |
| Bore position in 29200-series (smallest first) | 14 of 23 |
| Bore above smallest 29200-series size | 270 mm |
Cross references & equivalents
No verified interchange data yet. Send an inquiry and our team will confirm equivalents manually.
How the 29284 model number is decoded
29284 is a spherical roller thrust bearing to ISO 104 in the high-speed 292 series: asymmetrical barrel rollers running on a sphered housing washer, sized 420×580×95 mm, as listed in SKF catalogue PUB BU/P1 17000 ch. 13.1. The designation 29284 separates into 292 (series), 84 (420 mm bore) and no suffix (earlier standard design); washers are separable for individual mounting. The contact geometry also accepts simultaneous radial load up to roughly 55 % of the simultaneous axial force; beyond that mix, add a separate radial bearing to the arrangement. Static safety matters for shock duty: compare peak axial force against C0 9800 kN with the application's static factor, since crane hooks and screw positions see their worst load at zero or low speed. Mounting: fit the shaft washer tight on the 420 mm seat, seat the sphered housing washer on its matching (often separately supplied) seating washer, and check the assembly swivels freely before applying the 1990 kN working load.
Typical equipment & failure modes
Common applications
- marine shaft and rudder-style thrust positions with seat deflection
- 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
Known failure patterns
- smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established
- shaft-washer creep and fretting corrosion on a soft or undersized shaft shoulder
- oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips
- rolling-contact fatigue spalling after the catalogue L10 life is exhausted
- cage wear from rollers being dragged through unloaded zones under fluctuating thrust
Selection pitfalls — read before you substitute
- Above 300 mm bore the minimum load is large (A 9.1 here): design the preload or lift sequence explicitly — an unloaded slow rotation glazes the 580 mm washer track.
- 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 1990/9800 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.
- 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 29284.
- Minimum load factor A 9.1 dominates commissioning: start the oil flow and preload before rotation, especially on 292 bearings where an unloaded cold start smears the rollers.
- The 1990/9800 kN ratings and 75500 g mass are SKF catalogue values transcribed from ch. 13.1 of PUB BU/P1 17000 (PDF table page 928); 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
Why is the minimum axial load (A 9.1) so important?
Spherical roller thrust bearings skid and smear immediately when run unloaded — on large sizes factor A 9.1 corresponds to a substantial force. Springs, oil lift or the rotor/load weight must be applied before rotation, including cold test runs.
Can the 29284 also carry radial load?
Yes, up to roughly 55 % of the simultaneous axial force, thanks to the steep contact angle of the barrel rollers. Beyond that mix, specify a separate radial bearing; the primary duty remains one-direction thrust.
How is a 29284 mounted?
Tight shaft washer on the 420 mm seat, sphered housing washer on its matching seating washer, induction heating for large sizes, oil at the catalogue level before start, and the factor-A 9.1 preload verified at commissioning.
What are the dimensions and ratings of the 29284?
A 29284 measures 420 mm bore × 580 mm outside diameter × 95 mm width (16.535 × 22.835 × 3.74 in). From SKF catalogue PUB BU/P1 17000: dynamic C 1990 kN, static C0 9800 kN, fatigue limit Pu 815 kN, reference speed 630 r/min, limiting speed 1,000 r/min, mass about 75500 g. Minimum axial load factor A 9.1 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.