387A Bearing Dimensions
387A inch tapered roller bearing cone, paired with the 382A cup: 57.15 mm (2.250 in) bore, 96.838 mm OD, 21 mm width (FULI catalog). Quote.
387A specifications
| Cone bore d | 57.15 mm (2.250 in) |
|---|---|
| Cone width B | 21.946 mm |
| Matching cup | 382A |
| Cup outside diameter D | 96.838 mm (3.813 in) |
| Total width T | 21 mm (0.827 in) — assembled width of cup and cone |
| Seal / shield options | Open (cup and cone, no seals) |
| Material | GCr15 chrome bearing steel (rings and rolling elements) |
| Radial clearance | Set during mounting (adjustable, not a C-class value) |
| Load ratings | See the cone and cup pairs table below |
387A cone and cup pairs
| Cone | Cup | Bore d | OD D | Width T | Cr (kN) | C0r (kN) |
|---|---|---|---|---|---|---|
| 387A | 382A | 57.15 mm (2.250 in) | 96.838 mm (3.813 in) | 21 mm (0.827 in) | 81.6 | 102.1 |
Dimensions from FULI's catalog. A cone (inner ring with rollers and cage) and a cup (outer ring) make up one bearing; the pairs above are the matching numbers listed in FULI's catalog. Values from FULI's catalog; confirm for your application.
How to read the 387A designation
| Segment | Meaning |
|---|---|
| 387A | Designation breakdown not available for this model. |
387A interchange
387A is an inch tapered roller bearing cone. Inch tapered roller bearings are ordered by cone number and cup number. Most makers use the same cone and cup numbers for the same size, but always check the cup number as well. Send us the numbers on your old bearing and we confirm the match before quoting.
Brand names are trademarks of their respective owners. FULI is not affiliated with, authorized by or endorsed by these companies. Part numbers are shown for interchange reference only. FULI dimensions, load ratings and speeds come from the FULI catalog.
387A compared with nearby cone sizes
The 387A cone has a 57.15 mm (2.250 in) bore and a cone width of 21.946 mm. FULI's catalog pairs it with cup 382A (96.838 mm outside diameter, 21 mm total width).
The next smaller cone on this site is 28682, with a 57.15 mm bore (0 mm smaller) and cup 28622.
The next larger is 387S, with a 57.15 mm bore (0 mm larger) and cup 382A.
Cup 382A is also listed with 387S, 385 and 385A, so the same housing bore can take a different cone if the shaft size changes.
The metric tapered bearing on this site closest in bore is 32011 (55 × 90 × 23 mm). Its sizes differ from the 387A pair, so the two are not interchangeable; it is given only as a size reference.
| Cone | Cup | d × D × T | Cr (kN) |
|---|---|---|---|
| LM104949 | LM104911 | 50.8 × 82.55 × 21.59 mm | 70.5 |
| 385 | 382A | 55 × 96.838 × 21 mm | 81.6 |
| 28682 | 28622 | 57.15 × 97.63 × 24.608 mm | 90.5 |
| 387A | 382A | 57.15 × 96.838 × 21 mm | 81.6 |
| 387S | 382A | 57.15 × 96.838 × 21 mm | 81.6 |
| 45291 | 45220 | 57.15 × 104.775 × 30.162 mm | 132.9 |
| 555S | 552 | 57.15 × 123.825 × 38.1 mm | 163.8 |
Sizes and Cr from FULI's catalog; — = not listed on this site.
387A load ratings
387A/382A has a dynamic load rating Cr of 81.6 kN and a static rating C0r of 102.1 kN in FULI's catalog. The ratings belong to the cone and cup as a pair; a different cup changes them.
Speed limits and weights for inch cones are not listed in the catalog; ask us and we send them with the quotation.
Values from FULI's catalog; confirm for your application.
387A size in inches and millimetres
387A is made to inch sizes. The 57.15 mm bore is 2-1/4 in. The millimetre values in the catalog are conversions of the inch sizes.
| Dimension | Millimetres | Inches |
|---|---|---|
| Cone bore d | 57.15 mm | 2.2500 in |
| Cup outside diameter D (382A) | 96.838 mm | 3.8125 in |
| Total width T | 21 mm | 0.8268 in |
| Cone width B | 21.946 mm | 0.8640 in |
| Cup width C | 15.875 mm | 0.6250 in |
Converted at 1 in = 25.4 mm and rounded to four decimals.
Mounting 387A (general guidance)
General guidance, not a FULI specification: on a turning shaft the cone is a tight fit on the shaft and the cup a lighter fit in the housing, so the cup can be moved when the bearing pair is adjusted. Inch bearing fits are given as shaft and housing limits in inches in the bearing makers' tables; follow the drawing of your machine.
Tapered roller bearings carry radial load and axial load in one direction, so 387A is normally used as one of a pair, and the end play or preload is set at mounting.
If the outer ring turns and the shaft stands still, as in an idler pulley or a wheel hub, the fits are reversed: the housing gets the interference fit (for example N7 or P7) and the shaft a sliding one (g6 or h6).
Grease for 387A
FULI supplies tapered roller bearings rust-protected and normally without grease; grease is packed in when the bearing is mounted. Relubricating 387A/382A from the side takes about 10.2 g each time by the formula in our grease calculator: 0.005 × D × T = 0.005 × 96.84 × 21.
How FULI supplies 387A
387A is supplied as a cone, as a cup or as a complete cone and cup pair, as your order states. Where an order states a requirement for the total width T (21 mm for 387A/382A), each set is checked on a height gauge before packing.
Rings are marked with a brand you are authorised to use, with the FULI brand, or left neutral, as your order states. The box is printed with the model, precision class and brand.
Inquiries that give only one number are the usual cause of a wrong quote, so write both the cone and the cup number, for example 387A/382A.
Tools and guides for 387A
Typical applications
- Vehicle wheel hubs and axles
- Gearboxes and reducers
- Agricultural machinery
- Conveyor pulleys
FAQ
What size is 387A in mm?
The 387A cone has a 57.15 mm bore (2.250 in). With cup 382A the bearing is 57.15 × 96.838 × 21 mm (d × D × T).
What is the difference between 387A and 387S?
387S has a 57.15 mm bore against 57.15 mm for 387A, and pairs with cup 382A (57.15 × 96.838 × 21 mm) instead of 382A (57.15 × 96.838 × 21 mm). The two are not interchangeable; order by the numbers on the old cone and cup.
How much grease does 387A/382A need?
About 10.2 g each time it is relubricated from the side (0.005 × 96.84 × 21). FULI ships it rust-protected without grease, so the first fill is made at mounting.
Which cup goes with the 387A cone?
FULI's catalog pairs the 387A cone with cup 382A. Tell us whether you need the cone, the cup or both when you send the inquiry.
Is 387A the same size across brands?
387A is an inch tapered roller bearing cone number. Most makers use the same cone and cup numbers for the same size, but check the cup number too. Send us the numbers on your old bearing and we confirm the match.