61903 Deep Groove Ball Bearings Open Design, Self-retaining
The 61903 Miniature ball bearings are widely used in precision equipment with stringent space and precision requirements, such as: medical devices (dental handpieces, miniature pumps), precision instruments (flow meters, encoders), robots (miniature joints), optical equipment (camera focusing mechanisms), miniature motors, and aerospace precision instruments.
The 61903 bearing is a Deep groove ball bearings open design, self-retaining with an inner diameter of 17 mm , an outer diameter of 30 mm, a width of 7 mm. It typically uses PN grade precision tolerances and GCr15SiMn rings, Its dynamic radial rated load is approximately 4539 N, its static radial rated load is approximately 2516 N. It uses CN standard radial clearance, Open type, together determine its load-bearing capacity, rotational accuracy, and applicable working conditions.
Interchange code: TORRINGTON,FAFNIR 9303K , NSK 6903 , NACHI 6903 , NTN 6903 , KOYO 6903 , SKF 61903 , MRC 1903S ,
61903 bearings ( 17 mm x 30 mm x 7 mm) have the advantages of Small size, light weight, low friction, high speed, suitable for precision rotation in tiny spaces, and are therefore widely used in the Precision instruments, medical equipment, drones, robots, motors and various miniature transmission devices.
| Part Number | 61903 |
| Reference From | FAG 61903 |
| Bearing Type | Deep groove ball bearings open design, self-retaining |
| Series | 619 |
| Sealing | Open |
| Cage | JN = Stamping steel cage |
| Radial internal clearances | CN |
| Heat stabilization | SN = (up to 120 °C) |
| Lubricant | Without |
| Logistical code | HLC |
| Weight [lb] | 0.040 |
| Cr Radial Dynamic [lbf] | 1020 |
| C0r Radial static [lbf] | 565 |
| Cur Radial Fatigue [lbf] | 25 |
| nG Limiting speed [rpm] | 34461 |
| Operating temperature - T(min) [°C] | -30 |
| Operating temperature - T(max) [°C] | 120 |
| d φ Inside [inch] | 0.669 |
| D Φ Outside [inch] | 1.181 |
| B Width [inch] | 0.276 |
| D2 [inch] | 1.094 |
| r(min.) [inch] | 0.012 |
| D1 [inch] | 1.055 |
| d1 [inch] | 0.827 |
| Mounting dimensions | |
| da(min.) [inch] | 0.748 |
| Da(max.) [inch] | 1.102 |
| ra(max.) [inch] | 0.012 |
| Coefficient - F0 [inch] | 14.7 |
The 61903 Miniature ball bearings primarily consist of thin-walled inner and outer rings (precision machined), tiny steel balls (typically less than 3mm in diameter), and a cage (stamped steel or one-piece plastic). The most common type is the deep groove ball bearing, available in open, dust-covered, or sealed configurations, with inner diameters typically ranging from 1mm to 10mm.
Miniature ball bearings are small and lightweight, making them suitable for extremely compact spaces. They offer high rotational accuracy, reaching P4 level or higher, with smooth operation and low frictional torque. They exhibit significant low noise and low vibration characteristics, and some models feature a dustproof design to effectively prevent the intrusion of tiny particles, resulting in a long service life.
Share this product to:
Let more people see your product
