Wheel hub bearings are one of the key components of automobiles, and their main function is to carry weight and provide precise guidance for the rotation of the wheel hub. This requires them to not only withstand axial loads but also radial loads. The hub bearing unit is developed on the basis of standard angular contact ball bearings and tapered roller bearings. It integrates two sets of bearings and has advantages such as good assembly performance, negligible clearance adjustment, light weight, compact structure, large load capacity, the ability to pre load lubricating grease for sealed bearings, omission of external hub seals, and freedom from maintenance. It has been widely used in cars and is gradually expanding its application in heavy-duty vehicles.