The Bucket Wheel Excavator (BWE) is the main piece of harvesting equipment used in open-pit lignite or brown coal open-pit mines worldwide. Despite the continuous increase in size, productivity and technical sophistication in recent decades, they have not adapted to the changes of operating environment. In this respect, the increasingly frequent occurrence of hard inclusions – in terms of layers, boulders and other forms – has revealed a consistent failure of BWE-s to meet this challenge. This paper, inspired by the research project RFCR-CT-2015-00003-BEWEXMIN „Bucket wheel excavators operating under difficult mining conditions including un-mineable inclusions and geological structures with excessive mining resistance” deals with preliminary considerations and results that aim to contribute to solving this problem.
József András, József Kovács, Endre András, Ildikó Kertész and Ovidiu Bogdan Tomus
The bucket wheel excavator (BWE) is a continuous working rock harvesting device which removes the rock by means of buckets armoured with teeth, mounted on the wheel and which transfers rock on a main hauling system (generally a belt conveyor). The wheel rotates in a vertical plane and swings in the horizontal plane and raised / descended in the vertical plane by a boom. In this paper we propose a graphical-numerical method in order to calculate the power and energy requirements of the main harvesting structure (the bucket wheel) of the BWE. This approach - based on virtual models of the main working units of bucket wheel excavators and their working processes - is more convenient than those based on analytical formulas and simplification hypotheses, and leads to improved operation, reduced energy consumption, increased productivity and optimal use of available actuating power.