Slewing bearing is an important force transmission component required by a cutting mechanism that two mechanical components rotate in a relative circle and bear axial force and overturning moment radial force. Its main role is to bear the transmission and transmission force, so that the two parts of the mechanical components relative to the circular rotation it is suitable for a variety of different mechanisms of different rotating working state, is the basic components of machinery, is widely used in a variety of construction machinery large rotary device
1 Performance characteristics and structural forms of slewing bearings
Generally, slewing bearings are mainly composed of inner ring, outer ring, rolling body, isolation block, sealing device and grease. The outer seat ring of slewing support is connected with the turntable by bolts, and the inner seat ring by bolts. The form of slewing bearing structure is: according to the structure of the rolling body is divided into ball, roller and ball joint; According to the rolling body row number structure is divided into single row, double shake D platoon type; According to the raceway structure is divided into curved surface (arc), plane and steel wire raceway according to the transmission form is divided into outer teeth, inner teeth and toothless.
It is divided into four series by structure:
For the application, the most common type of slewing bearing four compare analysis, calculation, the raceway diameter and cross-sectional structure of similar size, cross roller type dynamic bearing capacity is higher, the static bearing capacity is higher, four-point contact ball type three row roller type comprehensive carrying capacity of the most high, the bearing capacity of the double type low contrast analysis of its technical economy, USES the following indicators:
Mark: M is the maximum overturning moment borne by the slewing bearing; W is the dead weight of the slewing bearing; S is the manufacturing price of slewing bearings.
Through the calculation and analysis of the aG value of nearly 500 kinds of slewing bearings of different specifications used in production, the conclusion is as follows: allowable load torque per unit dead weight, when the raceway diameter D is small, the cross roller structure is the worst, and the single-row four-point contact structure is better. When the raceway diameter D is large 1.7m, the three-row roller structure is the best