294-500-EM bearing: complete specifications & equivalents
The 294-500-EM is a ISO 104 radial bearing sized 500 x 870 x 224 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 500 mm |
| Outer diameter D | 870 mm |
| Width B | 224 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 9370 kN |
| Basic static load rating C0 | 40000 kN |
| Fatigue load limit Pu | 2850 kN |
| Reference speed (thermal) | 340 rpm |
| Limiting speed (mechanical) | 670 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 560000 g |
| Manufacturer designation | 294/500 EM |
| 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 & 29400-series range
| Bore d | 19.685 in |
|---|---|
| Outer diameter D | 34.252 in |
| Width B | 8.819 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 185 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) | 33 of 46 |
| Bore above smallest 29400-series size | 440 mm |
Cross references & equivalents
No verified interchange data yet. Send an inquiry and our team will confirm equivalents manually.
How the 294-500-EM model number is decoded
The heavy 294 series bearing 294/500 EM carries 9370 kN of thrust on barrel rollers whose contact angle also tolerates radial force up to a fraction of the applied thrust — the standard heavy-duty thrust bearing for 500 mm shafts. The designation 294/500 EM separates into 294 (series), 500 mm (slash-size) (500 mm bore — bore 500 mm is written directly after the slash) and EM; washers are separable for individual mounting. The machined brass EM cage is matched to size: brass cages tolerate the heaviest, slowest loads and marginal film conditions. The sphered housing washer self-aligns during mounting and under shaft deflection. Minimum axial load is explicit at factor A 150: below F_am = A·n² (or the catalogue's slow-speed floor) the barrel rollers skid; springs or the rotor's own weight are part of the selection, not an accessory. Verify the minimum axial load (factor A 150) immediately at commissioning — a cold start unloaded smears the rollers; spring preload or rotor weight must be present before the shaft rotates.
Typical equipment & failure modes
Common applications
- vertical hydro generators and large vertical pump motors
- coal mill, cement mill and sugar mill thrust bearings under shock load
- marine shaft and rudder-style thrust positions with seat deflection
- paper machine calender and refiner discs with combined axial and radial force
Known failure patterns
- smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established
- housing-washer rotation scored into an unmachined or loose seating face
- oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips
- false brinelling and rust-red witness marks on standby machines under external vibration
- 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 150 here): design the preload or lift sequence explicitly — an unloaded slow rotation glazes the 870 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 9370/40000 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.
- The spherical seat tolerates static misalignment, not a continuously rocking housing — a loose sphered seat frets under oscillation and needs the catalogue seat tolerances plus clean, greased contact.
- the 340 r/min reference speed is the thermal criterion under load, the 670 r/min limiting speed is the mechanical ceiling; large 294 bearings are normally run well below it with oil cooling.
- The 9370/40000 kN ratings and 560000 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
How is the 294/500 EM designation read?
294 is the dimension series (heavy 294 series) and 500 mm (slash-size) the 500 mm bore (the bore is written directly after the slash (no bore code)); EM is the cage execution (machined brass EM cage). The sphered housing washer provides self-alignment.
Why is the minimum axial load (A 150) so important?
Spherical roller thrust bearings skid and smear immediately when run unloaded — on large sizes factor A 150 corresponds to a substantial force. Springs, oil lift or the rotor/load weight must be applied before rotation, including cold test runs.
Can the 294/500 EM 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 294/500 EM mounted?
Tight shaft washer on the 500 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 150 preload verified at commissioning.
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.