SKF
SKF 71904 ACE/HCP4A Angular Contact Ball Bearing
Product Code:71904 ACE/HCP4A
Description
Dimensions d 20mmD 37mmB 9mmd1 25.65mmd2 24.4mmD1 31.49mmr1,2min.0.3mmr3,4min.0.15mma 11.6mmAbutment dimensions damin.22mmdbmin.22mmDamax.35mmDbmax.36.2mmramax.0.3mmrbmax.0.15mmdn 26.7mmCalculation data Basic dynamic load ratingC 4.68kNBasic static load ratingC0 2.28kNFatigue load limitPu 0.098kNAttainable speed for grease lubrication 60000r/minAttainable speed for oil-air lubrication 95000r/minBall diameterDw 4.762mmNumber of ballsz 14 Reference grease quantityGref 0.5cm³Preload and stiffness (back-to-back, face-to-face)Preload class AGA 42NStatic axial stiffness, preload class A 52N/µmPreload class BGB 130NStatic axial stiffness, preload class B 76N/µmPreload class CGC 250NStatic axial stiffness, preload class C 98N/µmCalculation factorsCalculation factorf 1.04 Calculation factorf1 0.98 Calculation factorf2A 1 Calculation factorf2B 1.04 Calculation factorf2C 1.08 Calculation factorfHC 1.01 Calculation factore 0.68 Calculation factor (single, tandem)Y2 0.87 Calculation factor (single, tandem)Y0 0.38 Calculation factor (single, tandem)X2 0.41 Calculation factor (back-to-back, face-to-face)Y1 0.92 Calculation factor (back-to-back, face-to-face)Y2 1.41 Calculation factor (back-to-back, face-to-face)Y0 0.76 Calculation factor (back-to-back, face-to-face)X2 0.67 Mass Mass bearing 0.032kg
Technical Specifications
Dimensions 
| d | 20 | mm | |
| D | 37 | mm | |
| B | 9 | mm | |
| d1 | 25.65 | mm | |
| d2 | 24.4 | mm | |
| D1 | 31.49 | mm | |
| r1,2 | min. | 0.3 | mm |
| r3,4 | min. | 0.15 | mm |
| a | 11.6 | mm |
Abutment dimensions 
| da | min. | 22 | mm |
| db | min. | 22 | mm |
| Da | max. | 35 | mm |
| Db | max. | 36.2 | mm |
| ra | max. | 0.3 | mm |
| rb | max. | 0.15 | mm |
| dn | 26.7 | mm |
Calculation data
| Basic dynamic load rating | C | 4.68 | kN | |
| Basic static load rating | C0 | 2.28 | kN | |
| Fatigue load limit | Pu | 0.098 | kN | |
| Attainable speed for grease lubrication | 60000 | r/min | ||
| Attainable speed for oil-air lubrication | 95000 | r/min | ||
| Ball diameter | Dw | 4.762 | mm | |
| Number of balls | z | 14 | ||
| Reference grease quantity | Gref | 0.5 | cm³ | |
| Preload and stiffness (back-to-back, face-to-face) | ||||
| Preload class A | GA | 42 | N | |
| Static axial stiffness, preload class A | 52 | N/µm | ||
| Preload class B | GB | 130 | N | |
| Static axial stiffness, preload class B | 76 | N/µm | ||
| Preload class C | GC | 250 | N | |
| Static axial stiffness, preload class C | 98 | N/µm | ||
| Calculation factors | ||||
| Calculation factor | f | 1.04 | ||
| Calculation factor | f1 | 0.98 | ||
| Calculation factor | f2A | 1 | ||
| Calculation factor | f2B | 1.04 | ||
| Calculation factor | f2C | 1.08 | ||
| Calculation factor | fHC | 1.01 | ||
| Calculation factor | e | 0.68 | ||
| Calculation factor (single, tandem) | Y2 | 0.87 | ||
| Calculation factor (single, tandem) | Y0 | 0.38 | ||
| Calculation factor (single, tandem) | X2 | 0.41 | ||
| Calculation factor (back-to-back, face-to-face) | Y1 | 0.92 | ||
| Calculation factor (back-to-back, face-to-face) | Y2 | 1.41 | ||
| Calculation factor (back-to-back, face-to-face) | Y0 | 0.76 | ||
| Calculation factor (back-to-back, face-to-face) | X2 | 0.67 | ||
Mass
| Mass bearing | 0.032 | kg |