This series comprises a set of precision bearings designed around a unified standard inner diameter of 0.125 inches (3.175 mm), offering mechanical engineers highly flexible options for component selection. Ranging from the thin-walled R144—featuring an outer diameter of just 0.25 inches—to the heavy-duty R2A, with an outer diameter reaching 0.5 inches, the series covers a comprehensive spectrum of applications, from lightweight power transmission to robust structural support. Every model in the series is manufactured using high-purity bearing steel and undergoes optimized heat treatment processes, ensuring that the bearings maintain superior physical properties across a wide range of operating temperatures.
Bearing Features
Technical specifications indicate that, depending on the specific outer diameter, the dynamic load ratings for this series range from 0.284 kN to 0.637 kN—capabilities that perfectly meet the power requirements of various home appliances, fitness equipment, and textile machinery. For instance, the R2 model—a representative of the series—boasts a high dynamic load rating of 0.637 kN and achieves a limiting speed of 58,000 RPM under oil lubrication. This design philosophy—characterized by the parallel development of multiple specifications—aims to resolve a common design challenge encountered in precision micro-machinery: situations where the shaft diameter is fixed while the load requirements vary significantly. Whether the application calls for the quiet operation demanded by home appliance motors or the exceptional wear resistance required for power tools, this product series offers an ideal specification with the precise balance of accuracy and strength to meet those specific needs.
Technical Specifications
| Bearing Reference | Boundary Diameters | Basic Dynamic | Basic Static | Limiting Speeds | ||||||||||||||||||
| Flange | Open | Shield | d inch |
d mm |
D inch |
D mm |
Df inch |
Df mm |
B inch |
B mm |
Bf inch |
Bf mm |
B1 inch |
B1 mm |
Bf1 inch |
Bf1 mm |
rsmin inch |
rsmin mm |
Cr kN |
Cor kN |
Grease | Oil |
| F | R144 | ZZ | 0.125 | 3.175 | 0.25 | 6.35 | 0.296 | 7.518 | 0.0938 | 2.381 | 0.023 | 0.584 | 0.1094 | 2.778 | 0.031 | 0.787 | 0.0039 | 0.1 | 0.314 | 0.108 | 6.9 | 7.8 |
| F | R2-5 | ZZ | 0.125 | 3.175 | 0.3125 | 7.938 | 0.359 | 9.119 | 0.1094 | 2.778 | 0.023 | 0.584 | 0.1406 | 3.572 | 0.031 | 0.787 | 0.0039 | 0.1 | 0.559 | 0.176 | 5.9 | 6.7 |
| F | R2-6 | ZZ | 0.125 | 3.175 | 0.375 | 9.525 | 0.422 | 10.719 | 0.1094 | 2.778 | 0.023 | 0.584 | 0.1406 | 3.572 | 0.031 | 0.787 | 0.0039 | 0.1 | 0.637 | 0.225 | 5.2 | 5.8 |
| F | R2 | ZZ | 0.125 | 3.175 | 0.375 | 9.525 | 0.44 | 11.176 | 0.1562 | 3.969 | 0.03 | 0.762 | 0.1562 | 3.969 | 0.03 | 0.762 | 0.0118 | 0.3 | 0.627 | 0.216 | 5.2 | 5.8 |
| - | R2A | ZZ | 0.125 | 3.175 | 0.5 | 12.7 | - | - | 0.1719 | 4.366 | - | - | 0.1719 | 4.366 | - | - | 0.0118 | 0.3 | 0.637 | 0.225 | 4.2 | 4.7 |

A flange bearing is a housed bearing assembly in which the outer housing carries a machined flange plate drilled with mounting holes. The flange plate allows the unit to be bolted directly onto a mac...
View MoreMost procurement teams comparing stainless steel bearings hold a material comparison sheet. 440C versus 316. Hardness versus corrosion resistance. Magnetic versus non-magnetic. None of that informati...
View MoreBearing Steel: The Metallurgical Foundation Behind Every Rolling Contact Every rotating assembly in modern machinery depends on a handful of highly engineered contact points. A pump running at 3,600 ...
View MoreAngular contact ball bearings are essential for handling combined loads because their inner and outer raceways are offset along the bearing axis. This built-in contact angle creates a direct, uninter...
View MoreIn a special production environment, many stainless steel bearings are equipped with corresponding sealing devices. On the one hand, it keeps the grease (oil) inside the stainless steel bearing from b...
View MoreUnder normal circumstances, stainless steel bearings will produce a certain amount of noise during machine operation. However, if the vibration level of stainless steel bearings increases significantl...
View MoreStainless steel bearings offer numerous advantages not only due to stringent manufacturing processes and precision requirements, but also because of the superior quality of the material itself. When s...
View More