What are the characteristics of slewing bearing materials?

The slewing bearing is mainly composed of ferrules, rolling elements, cages, sealing rings, etc. Since different parts have special functions in practical applications, there are different considerations in the design and selection of materials.

Under normal circumstances, the slewing ring rolling element adopts integrally hardened carbon-chromium bearing steel. The slewing ring is made of surface hardened steel. When the user has no special requirements, it is generally made of 50Mn steel, but sometimes in order to meet the needs of the host in some special applications, other grades of surface can also be selected according to the specific use conditions provided by the user Hardened steel, such as 42CrMo, 5CrMnMo, etc.

The medium and small slewing bearing forgings all use round or square bars as blanks. The grain structure and mechanical properties of the bar are uniform and good, the shape and size are accurate, and the surface quality is good, which is convenient for mass production. As long as the heating temperature and deformation conditions are reasonably controlled, forgings with excellent properties can be forged without large forging deformation. Ingots are only used for large forgings. The ingot is a cast structure with large columnar crystals and loose cores. Therefore, the columnar crystals must be broken into fine grains through large plastic deformation, and the looseness and compaction can be obtained in order to obtain excellent metal structure and mechanical properties.

The cage for the slewing bearing has a structure such as an integral type, a segmented type, and an isolated block type. Among them, the integral and segmented cages are made of No. 20 steel or ZL102 cast aluminum alloy. The isolation block is made of polyamide 1010 resin, ZL102 cast aluminum alloy, etc. With the continuous development of the material industry, nylon GRPA66.25 has also been promoted and applied in the design of segmented cages.

The material of the slewing ring seal is made of oil-resistant nitrile rubber. The code of the ferrule material and the supply status of the blank is in accordance with the regulations in the table. In the table, "T" indicates that the ferrule blank is supplied in a quenched and tempered state, and "Z" indicates that the ferrule blank is supplied in a normalized state.