Rolling bearing is a rolling bearing developed on the basis of plain bearings. Its working principle is to replace sliding friction with rolling friction. It is generally composed of two ferrules, a set of rolling elements and a cage. The versatility, standardization and serialization of mechanical basic parts. Due to the different working conditions of various machines, various requirements are imposed on the rolling bearing in terms of load capacity, structure and performance. For this reason, rolling bearings require a wide variety of structures. However, the most basic structure consists of the inner ring, the outer ring, the rolling elements and the cage - usually called four large pieces. For sealed bearings, add lubricant and seals (or dust caps) - also known as six large pieces. The various bearing type names are mostly named according to the name of the rolling element.

The role of various parts in the bearing is: for radial bearings, the inner ring usually fits tightly with the shaft and runs with the shaft. The outer ring usually transitions with the bearing housing or the mechanical housing bore. Fit, support. However, in some cases, there is also an outer ring running, the inner ring is fixed to support or the inner ring and the outer ring are simultaneously operated. For the weigh ring that fits tightly with the shaft and moves together, and the bearing ring or the mechanical housing hole is a transition fit and supports the seat ring. The rolling elements (steel balls, rollers or needles) are normally arranged in the bearing between the two ferrules by means of a cage for rolling motion. The shape, size and number of the bearings directly influence the load capacity and performance of the bearing. In addition to the uniform separation of the rolling elements, the cage can also function to guide the rotation of the rolling elements and improve the lubrication performance inside the bearing.