Double-Row Roller / Ball Combination Slewing Ring is a rotational rolling-element bearing or plain bearing that typically supports a heavy but slow-turning or slow-oscillating load, often a horizontal platform such as a conventional crane, a swing yarder, or the wind-facing platform of a horizontal-axis windmill. Compared to other rolling-element bearings, slewing ring bearings are thin in section and are often made in diameters of a meter or more. Slewing bearings are often made with gear teeth integral with the inner or outer race, used to drive the platform relative to the base. As a professional slewing rings supplier, we provide small and large swing bearing with high performance.

The bearings are comprised of two rings, each of which contains a precision raceway that is induction hardened on the surface to a specified depth. Each ring is made from a medium carbon steel forging. The bearings have raceways constructed in a four-point contact configuration, with 45° contact angles as standard. Other raceway configurations are available, such as crossed roller and eight-point contact. These other options are often considered in cases where very high loads or special stiffness requirements are needed.