Thrust ball bearing · 511 series
51120 bearing
100 × 135 × 25 mm
The 51120 is a thrust ball bearing with a 100 mm bore, 135 mm outside diameter and 25 mm height. Lightest single-direction thrust ball bearings.
- Bore d
- 100 mm 3.937 in
- Outside diameter D
- 135 mm 5.315 in
- Height H
- 25 mm 0.9843 in
- Dimension series
- 11
- Load directions
- Axial in one direction only
Designation explained
What 51120 means
Standard bearing numbers encode the type, the dimension series and the bore. Anything after the base number — seals, clearance, cage — is a suffix.
| Part | Meaning |
|---|---|
5 | Thrust ball bearing, single direction |
11 | Dimension series 11 (thrust) |
20 | 20 → 100 mm bore (20 × 5) |
Variants
Common 51120 variants
Suffixes change the bearing without changing its boundary dimensions. The exact letters differ between manufacturers — always order by the full designation from the maker you choose.
| Suffix | Example | Meaning |
|---|---|---|
(no suffix) | 51120 | Standard single-direction design: shaft washer, housing washer, ball and cage assembly |
M / TN | 51120-M | Cage material: brass (M) or polyamide (TN) — varies by size and maker |
Same bore
Other 100 mm bore bearings
Every standard bearing in this reference with a 100 mm bore, from light to heavy sections.
| Designation | Type | D | B / H |
|---|---|---|---|
| 6020 | Deep groove ball bearing | 150 mm | 24 mm |
| 6220 | Deep groove ball bearing | 180 mm | 34 mm |
| 6320 | Deep groove ball bearing | 215 mm | 47 mm |
| 61820 | Deep groove ball bearing | 125 mm | 13 mm |
| 61920 | Deep groove ball bearing | 140 mm | 20 mm |
| 1220 | Self-aligning ball bearing | 180 mm | 34 mm |
| 1320 | Self-aligning ball bearing | 215 mm | 47 mm |
| 2220 | Self-aligning ball bearing | 180 mm | 46 mm |
| 2320 | Self-aligning ball bearing | 215 mm | 73 mm |
| 7220 | Angular contact ball bearing | 180 mm | 34 mm |
| 7320 | Angular contact ball bearing | 215 mm | 47 mm |
| NU220 | Cylindrical roller bearing | 180 mm | 34 mm |
| NU320 | Cylindrical roller bearing | 215 mm | 47 mm |
| NU2220 | Cylindrical roller bearing | 180 mm | 46 mm |
| NU2320 | Cylindrical roller bearing | 215 mm | 73 mm |
| 22220 | Spherical roller bearing | 180 mm | 46 mm |
| 22320 | Spherical roller bearing | 215 mm | 73 mm |
| 30220 | Tapered roller bearing | 180 mm | 37 mm |
| 30320 | Tapered roller bearing | 215 mm | 51.5 mm |
| 32020X | Tapered roller bearing | 150 mm | 32 mm |
| 32220 | Tapered roller bearing | 180 mm | 49 mm |
| 51220 | Thrust ball bearing | 150 mm | 38 mm |
| 51320 | Thrust ball bearing | 170 mm | 55 mm |
Where to buy
Find 51120 at sellers
Search results on independent sellers. We are not affiliated with them, do not earn from these links and do not see their prices or stock. Results mix brands and variants — check the full designation before you order.
About these dimensions. Boundary dimensions follow ISO 104 (thrust bearings — boundary dimensions), dimension series 11, and are the same for every manufacturer of a standard 51120. Chamfers, load ratings, speed limits and weight depend on the manufacturer and design and are not shown — use the maker's datasheet for engineering decisions. Last checked 9 October 2026. Spotted an error? Tell us.
Learn more
What size is a 51120 bearing?
A 51120 is a thrust ball bearing with a 100 mm bore, 135 mm outside diameter and 25 mm height (100 × 135 × 25 mm). These boundary dimensions follow the ISO dimension plan, so they are the same across manufacturers.
Where are the load ratings and speed limits?
They depend on the manufacturer and internal design, so we do not list a single value. Check the datasheet for the exact full designation you intend to use.
Need 51120 data for a whole catalog?
We can help with that.
Normalized specifications, variants and supplier listings for every bearing you sell, with the source behind each value.