The slewing bearing (slewing ring) of a truck-mounted crane is the core joint connecting the truck chassis and the boom. It allows for 360-degree full rotation and withstands axial, radial, and overturning forces during lifting. The slewing bearing is made of high-strength alloy steel, offering high load-bearing capacity and precision, ensuring stable operation under heavy loads. The truck-mounted crane slewing bearing is a key component determining lifting flexibility, operational efficiency, and safety levels.