Belarusian National Technical University, Minsk, Belarus:

G. V. Kazachenko, Associate Professor, Candidate of Engineering Sciences, kazachenko@bntu.by
G. A. Basalay, Senior Lecturer

The authors discuss design of waling mechanisms intended for moving of single-bucket excavators. History of engineering and application of these mechanisms is given in brief. The authors also mention relations obtained for determining pressures and deformation of bearing surface under under the walking mechanism support shoes. The stability of walking excavators is considered with an assumption that the bearing surface deformation linearly depends on the pressure transferred to it by the excavator undercarriage. To understand the changes in the pressure on the bearing surface during walking, the cam walking mechanism work diagram is shown, which is divided into four typical phases for the convenience. The shape and dimensions of the bearing surface of the excavator during walking are studied, which makes it possible to find deformation of the bearing surface under the shoes. The analysis of energy consumed to move the excavator takes into account the gravity and friction forces, as well as the energy intake to overcome the inertial forces of lift and simultaneous turn of the machine in the vertical plane. The requirements of the machine movement are: the pressure under the excavator base must be lower than the allowable pressure for rock mass composing the bearing surface under analysis; the radius of the support base should be such that the pressure center is never beyond the core of crosssection. Determination of power for the operation of the walking mechanism is based on calculation of the energy consumption for lifting the excavator and overcoming friction between the excavator base and the bearing surface. Finally, the main outcomes of the study are summarized: the operation of the walking mechanisms is associated with significant dynamic loads induced in the machine steelworks; the power required for the operation of such mechanisms undergoes significant changes during walking and is mostly spent to overcome the resistance of the machine inertia; the power consumption is mostly associated with superstructure lifting and wheel dragging along the bearing surface given there is no backward slip of the shoes.

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