51228 bearing
140 × 200 mm · dynamic rating 190 kN · static rating 620 kN. Dimensions, load ratings, designation meaning, life estimates and equivalent parts.
51228 specification
| Designation | 51228 |
| Type | Single-direction thrust ball bearing |
| Series | 512 light-medium |
| Bore diameter d | 140 mm |
| Outside diameter D | 200 mm |
| Basic dynamic load rating C | 190 kN (190,000 N) |
| Basic static load rating C0 | 620 kN (620,000 N) |
| Ratio C0/C | 3.26 |
| Speed guide, grease lubrication | 1,900 rpm |
| Life exponent p | 3 (ball bearing) |
Values come from the Rotec AI bearing catalogue and are indicative. Confirm against the manufacturer's current catalogue before ordering. Not every dimension (such as width) is listed here.
What the designation 51228 means
| Code | Meaning |
|---|---|
| 512 | Single-direction thrust ball bearing, light-medium series (flat seat washers) |
| 28 | bore code "28" = 28 × 5 = 140 mm |
Basic rating life of the 51228
Basic rating life is L10 = (C / P)p million revolutions, where P is the equivalent dynamic load and p = 3 (ball bearing). For a 51228 with C = 190 kN, the table shows what that gives at different load levels. It is the ISO 281 basic life only: it does not include lubrication, contamination, misalignment or reliability modifiers.
| C / P | P as share of C | L10 (million rev) | L10 at 1,500 rpm | L10 at 3,000 rpm |
|---|---|---|---|---|
| 3 | 33.3% | 27 | 300 | 150 |
| 5 | 20.0% | 125 | 1,400 | 690 |
| 8 | 12.5% | 512 | 5,700 | 2,800 |
| 12 | 8.3% | 1,728 | 19,200 | 9,600 |
For example, a C / P of 5 means the equivalent load is 38 kN on this bearing. Use the Load Calculator to work out P for your actual radial and axial loads.
Equivalents of the 51228
Brand-by-brand equivalents for this exact designation are not yet in the Rotec AI cross-reference tables. The Cross-Reference tool accepts SKF, FAG, NSK, NTN, Timken, Koyo and NRB designations, and shows what is catalogued.
Where the 51228 is used
Thrust ball / thrust roller bearings are chosen for: Predominantly axial load. Typical equipment: Vertical pumps, extruders, turbines, marine and heavy gear drives. Thrust roller for higher axial capacity and shock.
Other sizes in the same series
The 51228 is size 22 of 28 in the Rotec AI catalogue for the “512 light-medium” series. The next size down, the 51226, has a bore of 130 mm and a dynamic rating of 186 kN. The next size up, the 51230 M, has a bore of 150 mm and a rating of 238 kN (+25%).
Common problems on bearings like the 51228
Most field failures trace back to lubrication, contamination, fits and alignment rather than the bearing itself. These guides explain how to recognise and prevent them:
Questions about the 51228
What are the dimensions of a 51228 bearing?
The 51228 has a bore of 140 mm and an outside diameter of 200 mm. It is a single-direction thrust ball bearing. Series: 512 light-medium.
What is the load rating of a 51228 bearing?
In the Rotec AI catalogue the 51228 has a basic dynamic load rating C of 190 kN and a basic static load rating C0 of 620 kN. Always confirm against the manufacturer's current catalogue.
What is the equivalent of a 51228 bearing?
Brand equivalents for the 51228 are not yet in the Rotec AI tables. Use the Cross-Reference tool to check other designations.