- Needle Roller Bearings: Needle roller bearings feature cylindrical rollers with a much smaller diameter-to-length ratio compared to cylindrical rollers. This design allows for a higher load-carrying capacity in a compact space, making needle roller bearings suitable for applications with limited radial space.

In summary, the purpose of the deep groove type of ball races in a ball bearing is to enable the bearing to support radial and axial loads, reduce friction, facilitate smooth rotation, distribute loads evenly, and contribute to the overall efficiency and reliability of the bearing in various mechanical applications.