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Drilling by the submersible drilling hammer is one of the progressive technologies in drilling of boreholes and it is currently being widely applied method for the drilling works. Use of the submersible hammers disposed in the borehole - drilling directly above the drilling tool - entails number of advantages. The most important is the energy loss prevention. Submersible drilling hammers are gradually and successfully replacing the surface hammers, which have been widely used for many years in Slovakia and in the ...

A starting point for roadheader robotisation (understood as a fully autonomous machine) is to automate the cutting process, which is the basic working process carried out by such machines. In case of boomпїЅtype roadheaders, it consists in automatic control of the movement of cutting heads to ensure that the face surface can be worked with optimum process parameters. This will guarantee high drilling efficiency (drilling advancement) and lower energy consumption, reduced dynamic loads and elimination of overloads....

The use of coal resources has contributed to the economy of Jiu Valley over a long period of time. Considering the long-term role of coal, many experts believe that the coal-based energy is sustainable, ensures energy security, and may become a growth factor in the area. The knowledge and technologies improvement for coal extracting from the Jiu Valley mining basin, where many mines were closed due to lack non-performing loans and lack of profitability, represents a first step in the sustainable rehabilitation of ...

The paper deals with the theoretical and practical analysis of the influence that the cutting direction of the bucket wheel excavator has on the digging forces acting on the wheel. Usually, when the terrace cut technology is applied, the bucket wheel of the excavator cuts vertical chips where mainly the perpendicular to stratification digging method is predominant. All the laboratory trials - done on the test rig - were conducted mainly for this type of vertical chip cutting. In cases when the drop cut method is a...

Jiu Valley represents one of the most important areas for coal mining in Romania, thus industrial development has generated a high level of health and safety at work issues. At work places in mining industry, the staff of the woodworking workshops is exposed to various concentrations of dust, possibly leading, in time, to occupational illnesses. Thus, wood processed in mining unitsпїЅ workshops is utilized for temporary support of coal faces, wrapping underground mining, insulation dams, ventilation doors, etc. Th...

Talc-bearing rocks in Kallievo-Murennanvaara deposit are associated with ultramafic rocks of peridotite-picritic series. Serpentinized rocks in the picritic portion of the sequence remained unaffected by talc alteration. Peidotitic komatiites, occurring below picrites which were altered to talc-carbonate rocks by carbon dioxide and then to talc-chloritic rocks under the influence of silica and alumina (the result of granite formation), were productive for soapstone. Kallievo-Murennanvaara soapstone deposit, is loc...

This paper presents a technical solution proposed for the mining drilling equipment command system, used for digging the horizontal mining works. The manufacturing industry of mining machinery in Romania and from different countries achieved a wide range of equipment for digging the horizontal mining works. As a result of the activity undertaken by a research team from the University of Petrosani, the drilling equipmentпїЅs with one manipulator arm (IMP-1) and two manipulator arms (IMP-2) were designed and constru...

Evaluation of explosion-proof protected electrical equipment in scope of certification is extremely important considering the risk of explosion that has to be minimized in order to ensure life safety and health of workers and to prevent damaging of property and the environment, as well as free movement of goods when they meet the essential safety requirements at European level. The purpose of this paper is to present the tests carried out on the cable entries with type of protection increased safety and flameproof...

In the Czech Republic, the production of energy using fossil fuels - particularly coal - is still a major proportion of total production. The energy sector is and will remain one of the most important areas of the Czech economy, ensuring supply of electricity and heat to the population and industrial enterprises. In the power and heating plants is burned primarily domestic brown coal mined in opencast mines in the north-western part of the Czech Republic, namely, Usti Region. For combustion of biomass in the Czech...

The minerals exploitation by explosives in quarries presume a high energy development for the applied blasting techniques with a proper design parameters establishment according in the field conditions where the blasting will carried out. For an optional rock blasting in field to obtain a certain granulation together with the maintaining the risk levels of blasting (seismic waves, fly-rocks, shock waves pressure) in a non - hazardous field, must to be applied sequential detachment of rocks from the massive with th...

The performances of the excavation machines depend largely on the tool and overall machine characteristics and on the other hand on physical mechanical characteristics of the excavated rock. There were more theories based on analytical deductions to explain the main cutting parameters on the basis of basic physical mechanical properties of the excavated rock. In this paper we use a new methodology, based on reliable laboratory data, which make possible to obtain correlation and regression formulas in order to pred...

Discussed are analyses and studies of an innovative method for managing active mining impact on future urban areas. Taking into consideration legal, methodological, engineering, economic, environmental, and social aspects, the solution represents an interdisciplinary attempt to address active mining damage problems. The examination follows a number of theoretical and practical analyses in addition to standard, numerical, and statistical calculations, as well as econometric models based on case studies and EU guide...

The use of pneumatic energy in industry as well as in the tertiary system is quite frequent representing 10% of the industrial electricity consumption in the European Union, the life span of compressors being relatively long, namely between 14 and 16 years depending on the installed power. Although the compressed air demand of a coal mine is covered by performant compressors manufactured by well-known producers there still are multiple possibilities to increase their energetic efficiency. The working method is con...

When building the foundations of a machine tool, demands must be placed on high quality and, above all, on their stability during their entire lifetime. In practice, however, it shows that these requirements are not always fully met on the customerпїЅs side when laying foundations. In the course of working, these foundations are subsequently damaged and their uneven decline occurs, which results in a change of the machine alignment, and thus it also influences the accuracy of production. For the supplier of the ma...

The specific energy consumption is mainly influenced by kinematics and dynamic measures of vertical transport installations as well as by the compatibility of different composing parts and their subcomponents. The optimisation of kinematics and dynamic parameters characterising a transport cycle is decisive considering the energy consumption. Also considering the operation of the vertical transport installations, as well as the character of the variation of kinematics and dynamic parameters during a race, it has b...

Mineral fuels are among the non-renewable natural resources. For this reason, would be addressed in a responsible and rational use. Mineral fuels are among the so called strategic raw materials, the use of which is essential to the national economy and energy security. Raw materials base in Slovakia as regards energy raw materials consists mainly of brown coal, lignite and uranium, part of the oil and natural gas. To determine the prospects for the use it is necessary to know the quantity of reserves and the econo...

Currently mobile mining machines, including primary ones, such as drilling and bolting rigs, or used in underground mining of metal ores, are most commonly driven by internal combustion engines. Due to the large depth of mining, this type of drive provides a number of disadvantages, including a large generation of fumes, heat and noise. The solution to this problem seems to be the use of the electrical battery drives, similarly as is the case in motor vehicles. The article presents the assumptions and boundary con...

The article deals with the structural design of the test equipment for analysis of coatings for hose conveyor belt conveyors. Processed list of existing test facilities in the world. Currently, there are various devices for testing materials using a bi-axial tension. The measuring device of its own production to measure axial forces in the conveyor belt, pipe conveyor is also the Technical University of Kosice. On it is possible to perform various tests conveyor belts by means of which the various measurements and...

Jiu Valley mining area is one of Romania where currently exploiting a coal deposit, which has important reserves of balance that can ensure beneficiaries' needs (CET Paroseni and CET Mintia) over a period of several decades. Structural changes that have occurred in the Romanian economy since 1989 have generated, but layoffs / redundancies collective personnel reorganization / activity restrictions in the mining units and the closure of some mines with no prospects of viability. All this led to a sharp economic dec...

The result of the experimental and analytical researches for the appointment of underground excavations, considering the interdependence with the type of rocks met, the working conditions and the safety of the supports have highlighted that the rational use of the actual types of supports, the improvement of the constructive parameters and the design of new types, as a unitary system, needs to be justified taking into account the study of the mechanism of the interaction. The analyses carried out for the rock cond...

The technology of cutting with a plasma arc is today a very advanced solution for thermally cuttable conductive materials. Plasma or also the plasma arc is composed of positively and negatively charged particles, excited and neutral atoms and molecules. As it contains free particles, it is electrically conductive and thus subject to the effects of an electric and magnetic field. This article discusses the use of plasma cutting technology on a CNC machine. The resulting quality of the plasma cutting is determined b...

The paper presents an innovative strain and temperature measurement method using the fibre Bragg grating (FBG) technology to monitor the design and operating safety of selected underground mining machinery and equipment. The system is based on the fibre Bragg grating (FBG) sensors or sensors using the optical time domain reflectometry (Optical Time Domain Reflectometry) technology. The essence of the solution is to introduce FBG sensors into the structure to make them act as its пїЅnervous systemпїЅ. Compared to c...

The purpose of the paper is inventarization, mapping and valorization of coal mining waste dumps, which occur in the area of Gliwice city (southern Poland, NW part of USCB), for the needs of reclamation and management of examined objects and defining potential recovery of coal from the dumps. Valorization of post-mining waste dumps has been done using original methodology, considering problems of reclamation, management, accessibility of the dumps as well as environmental hazards. On three valorized post-mining wa...

Processing of copper ore strongly depends on its parameters, therefore the more accurate identification of them should improve the process efficiency. The ore exploited in the KGHM underground mines in Poland is among the most difficult for processing, mostly due to its differentiated lithological compound. It can be identified at mining faces but on the way to processing plants through the complex transportation system consisting of trucks, sectional and main belt conveyors and ore bunkers, the portions of ore ha...

Nowadays surveying пїЅ geological departments of Polish coal mines conduct forecasts of leverages of underground mining on area and construction works based on J. BialekпїЅs formulas including, among others, distant leverages, reactivation of old workings and mining margin. The objective of this article is the adequacy study of the conducted forecasts of area deformation in this way with relation to real values of deformation indicators confirmed by surveys. For this purpose, an example of a really terminated expl...