Dyadechkin N.I.,Scientific Research Ore Mining Institute |
Temchenko A.A.,Krivii Rih National University |
Konstantinov G.V.,Krivii Rih National University |
Shipovskiy G.V.,Ingulets Mining and Concentration Plant
Gornyi Zhurnal | Year: 2013
Production capacity of mine transport equipment is the significant reserve of the growth of open-cast mining efficiency. Authors of this article have classified the factors, which have an influence on technical and exploitation production capacity of this equipment by the whole length of ore flow: from face to receiving bins of grinding and crushing factory. There were made the schemes of ore flows, which are more spread on iron-ore open pits of Krivii Rih basin (Ukraine). There was defined that most failures and unplanned outages of equipment are accidental, and all of them can be researched by probability theory and mathematical statistics. According to the results of controlling of mine transport equipment operation on the foregoing open pits (statistic massif is near 15 thousand hours) and processing of collected data, there was made an assessment of influence of reliability of separate chains of open pit ore flow (face shovel, autotransport, inter-open-pit crusher, mine transport) on total technological reliability of its functioning. According to this, there were given the corresponding statistic dependences. There was defined, that face shovel is the weakest (unreliable) chain. According to this, the forces of engineering plants and their equipment service maintenance, together with whole analytic and organization activity of mine enterprises should be aimed on increasing of reliability of this chain.
Sinchuk O.N.,Krivii Rih National University |
Guzov E.S.,Krivii Rih National University |
Parkhomenko R.A.,Krivii Rih National University |
Rozen V.P.,National Technical University of Ukraine
Gornyi Zhurnal | Year: 2013
This article gives the analysis of methods of calculation of electrical loads, applied on practice of designing of systems of electric-power supply of iron-ore and other industrial enterprises. It is substantiated as a fact, that most of these methods, applied nowadays, were designed more than 50 years ago. Nowadays these methods are outdated, because they do not correspond to modern realities. Moreover, in spite of various researches and theoretical developments of well-known methods, they include significant differences between calculation (project) and actual loads, which corresponds about imperfection of existing calculation methods. In modern marketable conditions, this leads to increasing of calculation values of installed powers of electric transformers of substations, and all elements of electric-power supply systems (electric power lines, tumblers etc.), which explains the range of negative consequences - from losses of electric power to non-efficient functioning of circuit separation units. As a consequence, there happens the rise in prices of the whole electrical equipment and electric-power supply system of ore-extraction unit, and, finally - the cost of extracted minerals. Consequently, there is required the searching of new calculation methods. According to analysis of methods of calculation of electrical loads and corresponding coefficients, they should be oriented not on account of separate consumers with individuality of their operation modes, but on the total assessment of power consumption, according to technological groups of consumers, which operation modes are interconnected and substantiated by technological processes. This conclusion corresponds to the structure of real electric-power supply systems, and gives a possibility to check the correctness of calculations and to adjust the design factors, using operational instrumentation. This article gives a new author's view of approach (generalized method) to calculation of electric-power supply parameters, according to technological groups of consumers, which corresponds to real structures of electric-power supply of iron ore enterprises, which are operated nowadays. According to results of calculations and nature researches, new method makes it possible to make a 1.5-2 times decrease of transformer capacities of both separate substations, and whole mining enterprise with corresponding decreasing of capital and exploitation costs.