Abstract
The sustainability of lignite production requires, among other factors, cost reduction, high efficiency, as well as the increase of the production capacity. In order to rationalize and increase the efficiency of lignite mines, the optimization of the production process is necessary. In this respect, equipment revitalization and modernization is a key issue. This paper deals with the analysis of the time response of the boom structure of a bucket wheel excavator (BWE) during operation. For this, we propose a virtual model of the boom, on which a variable-in-time force generated by the bucket wheel acts. The kinematic drive chain of the bucket wheel and the conveyor belt, which are also vibration generators, were simulated only by the static load produced on the excavator’s boom. Thus, it is possible to highlight the time response of the load-bearing structure (the boom) of the bucket wheel to the action of forces resulting from the cutting of the face under pretensioning conditions. The forces generated by the excavation process have high values and a slow variation over time, depending on the bucket wheel’s rotation speed and the number of buckets installed on the wheel. The dynamic time response simulation was performed considering the global damping variation as dependent on frequency. The simulation was done for both the excavation of a homogeneous material and for the case of the sudden appearance of a hard material inclusion (boulder) during homogenous material cutting.
Highlights
Lignite, as an energy resource, still has a significant share in the energy mix of many countries, in Europe and worldwide
We defined a a mathematical model of the resultant of the excavation forces—which are the main source of mathematical model of the resultant of the excavation forces—which are the main source of vibration vibration of the boom structure—and we determined the static loads acting on the boom of the bucket wheel excavator (BWE)
Of the boom structure—and we determined the static loads acting on the boom of the BWE
Summary
As an energy resource, still has a significant share in the energy mix of many countries, in Europe and worldwide. Theenergy rotorofof theanalyzed analyzed equipped withthat nineresults cutting–loading buckets andnine ninecutting cutting buckets Between these two energy consumption components, the energy necessary for cutting the material is predominant, representing 60%–90% [6] or 70%–90%, according to [7], of the energy necessary to operate the bucket wheel. Only those forces that correspond to the actual cutting were taken into consideration in the simulation. The variation intervals [8]. in forces shown in Figure 4a,b and Figure 5 corresponds to a single cutter–loader
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
