Slewing bearings can be categorized into three types: external tooth slewing bearings, internal tooth slewing bearings, and toothless slewing bearings. When choosing between internal tooth and external tooth slewing bearings, it is important to consider their advantages and disadvantages.

Internal tooth slewing bearing: The internal gear of this type is located inside the slewing bearing, giving it a relatively clean appearance. The engagement between the driving gear and the slewing bearing takes place internally, eliminating the need for a safety cover. The internal gear provides better resistance to dust, and the lubricant can be retained for a longer duration. The contact stress during internal tooth meshing is low, resulting in minimal wear and a longer service life. However, due to the size limitations of the internal tooth slewing bearing, the internal space is relatively compact. This can make installation and initial debugging more challenging, as well as fault diagnosis and gear meshing inspection in later stages.

External tooth slewing bearing: The teeth of the external tooth slewing bearing are located outside the slewing bearing, making it easier to install and allowing for maximum utilization of the limited space within the bearing. Fault diagnosis and gear meshing inspection are simpler in this configuration. The larger pitch diameter of the ring gear enables a higher transmission ratio and significantly reduces the circumferential force and torque on the pinion.

In summary, the choice between internal tooth and external tooth slewing bearings depends on the specific requirements of the application. Internal tooth slewing bearings offer advantages such as cleanliness, better dust resistance, lower wear, and longer service life. However, they may pose challenges in terms of limited internal space and installation/debugging processes. On the other hand, external tooth slewing bearings are easy to install, allow for efficient space utilization, and facilitate fault diagnosis and gear meshing inspection. They are particularly suitable for applications requiring a higher transmission ratio and reduced circumferential force and torque on the pinion.