How slewing rings work

Slewing bearing are large bearings that can be developed in the late 1950s to withstand combined loads (axial, radial and overturning moments). The slewing bearing has a mounting hole, an internal ring gear or an external ring gear, a spacer block, a cage, a lubricating oil hole and a sealing rubber, so that the design of the main body is compact, the guiding is simple, and the maintenance is easy.

Xuzhou Wanda Slewing bearing has nongear type, external gear and internal gear type single volleyball type, double row ball type, double row ball type, single row cross roller type, three rows of roller type, ball column combined type The series, in which the single-row cross-roller slewing bearing developed the earliest, and the single-row four-point contact ball was launched 85 years ago, followed by large-scale replacement bearings, the slewing bearing material is also more abundant, 50mn material strength is high, the price is higher Moderately, 42crmo has high strength, good flexibility and a slightly higher price. The performance of S48C products is between the two. Stainless steel slewing bearings are also widely used, but the biggest disadvantage is that they cannot be quenched and cannot be loaded. Closer to home, let's take a look at the working principle of the slewing ring in the excavator.

The slewing bearing device of the excavator is composed of a turntable, a slewing ring and a slewing mechanism. The outer race of the slewing ring is connected with the turntable by high-strength bolts (pre-tightening the bolts in three stages), the inner ring and the bottom with teeth The frame is connected by bolts, and rolling elements are arranged between the inner and outer races. The rolling elements are generally divided into a spherical shape and a cylindrical shape. The vertical load and level of the excavator working device acting on the turntable are selected according to different working conditions of the user. The load and the overturning moment are transmitted to the chassis through the outer race, the rolling elements and the inner race of the slewing ring. The housing of the slewing mechanism is fixed on the turntable, and meshes with the ring gear on the inner race of the slewing bearing through the pinion gear. It is particularly important to adjust the gap during the initial installation. For details, refer to the technical information about the slewing bearing clearance of the station. Therefore, the pinion can rotate around its own axis and revolve around the center line of the turntable. When the swing mechanism works, the turntable rotates relative to the chassis. Due to the harsh working conditions of the excavator, regular maintenance can increase the service life of the excavator slewing bearing to a certain extent.