Spectra of slewing bearing load of a rotating-platform drive in hydraulic excavators

The paper presents a mathematical model for the determination of spectra of equivalent slewing bearing loads of a rotating platform drive in hydraulic excavators with a backhoe attachment. The spectrum of equivalent bearing loads is dened on the basis of possible digging resistances which represent the minimal value from a set of boundary digging resistances that enable the stability of the excavator and boundary digging resistances which can be overcome by the excavator drive mechanisms. The same models of the excavator can have dierent variants of the kinematic chain which can occupy a number of dierent positions and working conditions. Hence, based on the general mathematical model a software was developed for a detailed analysis of the slewing bearing load of a rotating platform drive for a desired number of positions in the entire working range of the excavator for every possible variant of the kinematic chain.