Truck Crane Slewing Bearing

The truck crane slewing bearing is used for mobile truck cranes. Because it bears axial force, radial force and overturning force during operation, it generally uses an external gear single-row four-point contact ball slewing bearing or a double-row ball (eight-point contact ball) slewing bearing.

The slewing bearing of the truck crane is mainly composed of an outer ring, an inner ring, a steel ball and an isolating block or a retaining frame. Among them, the outer ring and the inner ring are support rings, the steel ball is the supporting rolling body, and the isolating block or retaining frame is used to keep the position of the ball. The raceway usually adopts a peach-shaped groove, medium-frequency surface quenching treatment, the surface hardness of the raceway can reach HRC55-60, and the depth of the hardened layer can reach 2.5~5mm. The raceway and the steel ball are loaded in a four-point contact manner. The curvature radius of the raceway is accurately calculated to ensure that the rolling body can roll smoothly during the rotation process, reducing rolling resistance and energy loss. The outer ring teeth are generally treated by medium-frequency quenching heat treatment, and the tooth surface hardness is recommended to be HRC45~50.

Because the product needs to withstand a large overturning moment during operation, the radial clearance of the bearing should be smaller under the premise of no jamming during rotation. Generally, it needs to be controlled within 0.05mm, and the radial clearance also needs to be controlled within 0.1mm, so that it can be smooth and stable during use.