7008 ACBGA/P4A
Super-precision, high-speed B design, universally matchable single row angular contact ball bearingThese super-precision, high-speed, single row angular contact ball bearings with 15° or 25° contact angle accommodate radial and axial loads acting simultaneously, where the axial load acts in one direction only. Compared to the equivalent SKF E design high-speed bearings, these are suited for lighter loads. Being universally matchable, they can be used together in arrangements to provide effective load sharing, within a predetermined preload range, without the use of shims or similar devices.
- Very high running accuracy
- Accommodate high speeds
- Reduced stresses on rolling contact surfaces
- Universally matchable
Description
| Universal matching bearing(s) | Yes, back-to-back (<>), face-to-face (><) or tandem (>>) |
Dimensions
| d | 40 mm | Bore diameter |
|---|---|---|
| D | 68 mm | Outside diameter |
| B | 15 mm | Width |
| d1 | 50.95 mm | Shoulder diameter of inner ring (large side face) |
| d2 | 49.87 mm | Shoulder diameter of inner ring (small side face) |
| D2 | 58.88 mm | Recess diameter of outer ring (large side face) |
| D4 | 60.22 mm | Recess diameter outer ring shoulder (small side face) |
| r1,2 | min. 1 mm | Chamfer dimension |
| r3,4 | min. 0.6 mm | Chamfer dimension |
| a | 20.2 mm | Distance from side face to pressure point |
Abutment dimensions
| da | min. 44.6 mm | Diameter of shaft abutment |
|---|---|---|
| db | min. 44.6 mm | Diameter of shaft abutment |
| Da | max. 63.4 mm | Diameter of housing abutment |
| Db | max. 64.8 mm | Diameter of housing abutment |
| ra | max. 1 mm | Radius of fillet |
| rb | max. 0.6 mm | Radius of fillet |
| dn | 51.6 mm | Position of oil nozzle |
Calculation data
| Basic dynamic load rating | C | 6.89 kN |
|---|---|---|
| Basic static load rating | C0 | 5.3 kN |
| Fatigue load limit | Pu | 0.224 kN |
| Contact angle | α | 25 ° |
| Ball diameter | Dw | 4.762 mm |
| Number of balls (per bearing) | z | 26 |
| Reference grease quantity (per bearing) | Gref | 2.22 cm³ |
| Preload class A | GA | 41 N |
|---|---|---|
| Axial stiffness for preload A (sets of two brgs back-to-back or face-to-face) | 71 N/µm |
| Correction factor dependent on bearing series and size | f | 1.04 |
|---|---|---|
| Correction factor dependent on contact angle | f1 | 0.99 |
| Correction factor, preload class A | f2A | 1 |
| Correction factor for hybrid bearings | fHC | 1 |
| Limiting value | e | 0.68 |
| Axial load factor (single, tandem) | Y1 | 0 |
| Axial load factor (single, tandem) | Y2 | 0.87 |
| Axial load factor (single, tandem) | Y0 | 0.38 |
| Radial load factor (single, tandem) | X1 | 1 |
| Radial load factor (single, tandem) | X2 | 0.41 |
| Radial load factor (single, tandem) | X0 | 0.5 |
| Axial load factor (back-to-back, face-to-face) | Y1 | 0.92 |
| Axial load factor (back-to-back, face-to-face) | Y2 | 1.41 |
| Axial load factor (back-to-back, face-to-face) | Y0 | 0.76 |
| Radial load factor (back-to-back, face-to-face) | X1 | 1 |
| Radial load factor (back-to-back, face-to-face) | X2 | 0.67 |
| Radial load factor (back-to-back, face-to-face) | X0 | 1 |
Mass
| Mass | 0.21 kg |
Tolerances and clearances
Product details
- Tolerances: P4A, P4B, P4, PA9A, P2
- Clamping and fitting forces: D design, E design, B design
- Designation suffixes H, H1, L and L1 identify variants for direct oil-air lubrication.
Principles of bearing selection and application
- Chamfer dimensions
- Seat tolerances for standard conditions: shafts, housings
- Values for ISO tolerance classes: shafts, housings
- Speed dependent initial grease fill → Initial grease fill
