638 Bearing | AXIS 638 Miniature Ball Bearing - 8x28x8

This 638 Bearing is a high-precision premium miniature ball bearing made to ABEC 3 precision standards from AXIS. What sets this 638 bearing apart from others is the ABEC 3 precision standard that this bearing is made to, the grade 10-balls used, and the superb electric motor quality rating (EMQ). ABEC 3 means that the bearing itself has a micron deviation from a nominal of 20.000mm of -8 micrometers. The standard ABEC 1 precision standard that almost all ball bearings are made to today has a deviation of -10 micrometers. In simple terms, the more precision a bearing is, the better it will perform in any given application especially when pertaining to a miniature bearing. The grade 10 balls within this bearing are typically only found within ABEC 5 or higher bearings because of their more true roundness and precision. The balls within a bearing share the load capacity, so this also increases the working life versus the standard grade 25 balls used in other brands. The electric motor quality rating means that the bearing must operate at an extremely low noise level with minimal to no vibration. To achieve this, the 638 bearing features raceways that are precision honed to a superb finish.

More specifically, 638 miniature bearings are found within a broad range of industrial and scientific applications such as medical and industrial handpieces, flow meters, fuel controls, gyros, synchros, servos, motors, cryogenic coolers, pulmonary assist devices, and more. For additional information or to get a quote on a 638 miniature ball bearing contact our customer support team and we will be happy to assist you!

638 Miniature Bearing Dimensions

• Bearing Size: 638
• Dimension (d): 8mm
• Dimension (D): 28mm
• Dimension (B): 8mm
• Dynamic Load Rating: 750 LBS
• Static Load Rating: 315 LBS
• Grease Limiting Speed: 28000 RPM
• Oil Limiting Speed: 34000 RPM
• Weight: 0.062 LBS