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A wireless system of continuous monitoring of pressure in a leg mounted in a powered roof support was designed in order to ensure the continuity of longwall coal mining process. Wireless multi-channel signal transmission in the longwall was applied for the first time. The extension of the power cell enabled maintenance-free use of the system and ensured comprehensive control of the support. The presented system monitors the pressure value in the spaces under the leg?s piston mounted in a powered roof support as we...

Fuel and energy management and related energy security are key issues for every country. The selection of energy sources used by individual countries depends on the possessed resources of energy raw materials, the economic position and, to an increasing extent, the approach to environmental protection. These factors shape the so-called energy policy of a given country. In the case of Poland, this policy is based on conventional energy sources. The main energy resource of the country is hard coal, the extraction of...

One of the major problems associated with exploitation of the copper ore deposit in underground mines in Poland is the local disturbance in a state of stable equilibrium manifested in a sudden release of strain energy stored in the deformed rock mass. It occurs mainly in the form of dynamic events which may result in rockbursts and roof falls. In order to face this threats, a number of organisational and technical prevention methods are applied in mines. It should be also noted that the greatest difficulties with ...

The subject of this paper is the assessment of the influence of the construction and design elements on traffic safety at level crossings in undermined areas. The first part is dedicated to level crossings in the Czech Republic and accident rates at level crossings in the Moravian-Silesian Region. The following part describes the in situ experiment, which was conducted at selected crossings with different types of safety arrangements, intensity of traffic and traffic moments. Our results were compared with the res...

The copper ore deposit in Poland is extracted by three underground mines which belong to KGHM Polish Copper JSC. Since the very beginning, copper ore mining has been accompanied by seismic activity and rock-burst hazard controlled by means of several prevention activities aiming at assessing and combating the danger. Seismology is the prime method to measure seismic activity i.e. the number and energy of rock mass shocks. The hazard monitoring also encompasses measurements of the convergence of mine workings, i.e....

Extraction of the copper ore deposit in the Legnica-G?ogow Copper Basin in Poland is usually associated with high seismic activity. In order to face this threats, a number of organizational and technical prevention methods are utilized, from which blasting works seem to be the most effective. A significant number of recorded dynamic events may be clearly and directly explained by the effects of this approach. It is also expected, that the simultaneous firing of a number of mining faces may provide the amplificatio...

For underground extraction of coal are running a complex network mining vertical, horizontal and inclined role extraction, transportation and evacuation on the surface. Associated system of mining works has the ventilation network to ensure the oxygen necessary for workers, diluting explosive gases and toxic substances and evacuated heat and humidity from the underground. For air evacuation from the underground workings, from the point of entry of fresh air to the polluted air exit point, is used powerful fans loc...

This article presents the analysis of the existing schemes of mining, logistics and consumption of fuel in North Yakutia which ones are form technological chains unique in complexity of management. This is due to negative impact of a large number of analyzed factors. The general trend is towards to reduction of coal consumption in hard-to-reach regions. Therefore, local coal deposits near the key points of consumption are not developed. Geotechnical and economic indicators of small-scale coal mines are generally l...

This paper refers on the result of an experimental work developed in a quarrying site aimed to test the reliability of geostatistical approach as an alternative tool in the assessment of spatial variability of professional hazards. The case study is referred to the exposure of workers to airborne dust generated from typical quarrying activities. In such a risk assessment procedure in fact, the most useful alternative method to personal sampling is represented by defining the space-time variability of the physical ...

The strategic management of the mining companies involved in the extraction and processing of energy raw materials still lacked a strategic tool to help determine the patterns of extraction of energy resources in the development of the external environment or external conditions. In this article, the authors sought to find a possible econometric model of black coal. Research is based on data available from the macroeconomics and mining of the selected mineral, which are analyzed using the multidimensional regressi...

The paper presents results of experimental study of microstructural changes in rock specimens under the effect of high pulse pressure due to shock waves. Specimens of strong rock and coal were placed into special steel preservation ampoules. Shock waves were generated by explosion of trotyl blocks. The study involved electron microscopy, micro- and nanoindentation and laser spectroscopy of particle size. Images of specimen surface fragments were obtained by electron microscopy at various scale levels before and af...

Computer assisted design and simulation are essential stages in the process of creating a new technical product. The paper presents the utilization of cutting parts, equipping 2K-52 machines, as fundamental element in the development of modified cutting parts for KSW-460NE machine. This modification has been possible due to the study of the machine?s cutting parts with the help of CAD/CAE software. Adapting the cutting parts to KSW-460NE machine has been imposed by the geological-mining conditions of the coal laye...

It is important to analyze the current state of a person during respiration in individual breathing apparatus. For that reason, you need to register cardiorespiratory parameters of a human. Reusable simulators of breathing apparatus with specific hardware and software are used for these purposes. They allow simulating the conditions of the breathing, equivalent to primary breathing apparatus with chemically bound oxygen. During the development of the mine insulating self-rescuer simulator for the personnel of mini...

The use of a trenchless method of laying underground utilities is an advantageous alternative to the use of open methods. The method of vibro-impact immersion in the ground of steel pipes with an open front end is widely used in the construction of closed underground passages. Determining the trajectory of a clogged pipe is one of the most important operations in this technology. The article describes result of laboratory tests of prototype model of strapdown inertial navigation system designed in N.A. Chinakal In...

Introducing new technical solutions into practice is inseparably connected with a number of problems. In addition to obvious concerns about the quality, reliability and effectiveness of the solution, there are also social problems. They are related to distrust of employees regarding new solutions and is caused by a limited knowledge about the introduced product which is related to employees' concerns that such a product may disturb the existing state of balance. Therefore, in the case of introducing a new solution...

It is generally recognized that bus drivers are potentially being exposed to daily vibration levels higher than recommended by the international guidelines, especially on certain road types in the urban context. The literature shows up that the whole body vibrations exposure may contribute to low back pain and produce negative effects on the human health. The principal issue about the relationship between exposure and biodynamic response has not been clarified yet. The purpose of this paper is to determine the lev...

Impact of horizontal stresses on stability of underground workings in mines is a very important issue in underground mining. Identification of the initial state of stress in the rock-mass should be one of the main actions taken into account while designing and carrying out the mining activity in underground mines. The paper presents the azimuths difference method. This innovative method can be used to estimate numerical quantity of the perpendicular and parallel horizontal stress around underground mining excavati...

The paper presents the results of the analysis of the accuracy of estimates of copper resources in parts of a Cu-Ag deposit in the Lubin-Glogow Copper District (LGCD) (Poland) where samples were not collected (test areas). The estimation was based on the samples collected from excavations surrounding the areas scheduled for mining activities, while the evaluation of the accuracy of the estimates was based on data obtained during the exploitation. The estimates of resources in the examined area were based on a 3D s...

This paper addresses mechanisms of destruction of methane-saturated coal at micro- and macro-levels under dynamical impact due to methane transition from its natural bound to a free state. The focus is on possible destruction of practically impenetrable (crushed and pressed) coal. Our study is based on analysis of experimental investigations and computed modeling. The experimental investigations involved experiments with rock pre-cracking under explosive impact and analysis of photo images of coal microstructure a...

In order to ensure energy security, at national level, coal constitutes an important source, though its share in the energy mix is reduced in the past few years in favor of clean technologies and on the background of the fall in the energy consumption. Where can be located in the project of energy security, the production of coal, exploited in the mining units in the Jiu Valley and valorized at the two power plants, Mintia and Paroseni-components of the Hunedoara Energy Complex, amid the request for intervention f...

The dynamic changes occurring in recent years in the global industry have been referred to as the fourth industrial revolution. The main assumption behind this concept is extensive implementation of IT and ICT developments into production processes. Production processes should make maximum use of the latest technologies, thus leading to the creation of intelligent factories in the end. In such a factory, wireless network systems are supposed to quickly and reliably combine all the components of the production proc...

The paper deals with the influence of mining works on the transport in the area mainly the structural layers of transport-related engineering structures elements as railways, roads, railway crossings and the overall transport system. Long-term underground coal mining is usually associated with environmental impacts in the Moravian-Silesian Region in the Czech Republic. There are two types of undermined areas in mentioned region: District of Ostrava where the mines were closed and the mining phenomena are considere...

High level of mining in Polish copper mines, in the Legnica-Glogow Copper Belt (LGOM), caused an increasing amount of mining works to be carried out in difficult geological and mining conditions, for instance in the vicinity of remnants. Issues related to performing mining operations with the use of the room and pillar mining system in the vicinity of remnants is important in terms of work safety. Remnants are sites of the concentration of high stress values and may affect rock layers of the rock mass located in t...

Biomass belongs among renewable energy sources and its representation in national energy strategies is increasing due to the limited supplies of fossil fuels. One of the options for substitution of fossil fuels is short rotation cropping systems for woody biomass as a method of reclamation and revitalization of anthropogenic soil profiles during restoration activities in the areas after brown coal mining. The scope of the project "Methodology of sustainable agricultural management in anthropogenic damaged landscap...

During the extraction of minerals in underground mines or surface mines all material extracted must be transported long distances. This transport is usually done using belt conveyors. For the transport of rocks to a mine disposal site, a combination of multiple belt conveyors is necessary. This material must be poured from one belt conveyor to another. At the places of transfer, the upper protecting layers of the conveyor belts are often damaged due to the impact of the material. This deterioration of contact laye...

The purpose of this expertise is to evaluate by mathematical modeling the stability of the slag and ash deposit Compartment II Emergency Cicani, which will be carried out on the past site of the Cicani Mid-East compartment by elevation with a height of 3,0-3,5 m, up to + 178mdMN. The deposit will be made using the "thick slurry" technology, having as foundation the deposition of slag and ash existing in the Cicani Middle + East (existing) compartment, made by the hydraulic transport technology. The basses of the e...

The Cu-Ag deposit exploited in the Lubin-G?og?w Copper district (LGCD) in Poland is located in the Permian Rotliegend (sandstones) and Zechstein (shale and carbonate rocks) formations. The three main lithological series are not internally homogenous; within them, a total of 16 individual lithological units can be determined. The differentiation between lithological, mineralogical and geometallurgical ore properties is a criterion used to distinguish between main and individual lithologies in the deposit area. A sy...

The subject of the study was to characterize three deposit parameters of Pacific polymetallic nodules (the content and the abundance of nickel and the nodule abundance) using classical statistical methods. The input data points come from 448 sampling points of a bed area of about 48,000 km2 in the Clarion-Clipperton fracture zone (approx. 1,000 km west of the coast of Mexico). The sample points formed a pseudoregular grid with an average distance between them of about 10 km. On the basis of these, the basic statis...

A tough requirement for the development of the Partomchorr apatite-nepheline ore deposit containing rare-earth elements is a performance of environmental safety of production, because a sanitary zone of the projected mining and processing plant sides with the boundaries of the existing Simbozersky nature reserve and the created Khibiny national park. The studies have substantiated reasonability of the Partomchorr deposit development by a combined mining method; in the first stage step-by-step mining of four open p...

The technology of cutting with a laser beam today is a widespread solution for thermally cuttable materials. In mechanical engineering laser technologies currently, belong among the most progressive ways how a person can act on materials within the production process. Machining and processing materials using a laser is based on the conversion of light energy into heat energy. According to the active environment, a distinction can be made between three basic types of lasers - gas, solid state and semiconducting. Th...

The technology of oxy-cutting is a widespread solution for thermally cuttable materials nowadays. This article discusses the use of oxy-cutting technology on CNC machines. This technology is particularly suitable for unalloyed and low-alloy steels and cast steels. With the help of this technology, it is possible to cut sheets ranging from 3 to 1000 mm. For sheets with a thickness of 20 mm it is preferable to use a laser or plasma technology. When cutting with an oxy-fuel the workpiece it is initially heated on the...

In the era of dynamically changing business environment, planning in an enterprise is a part of decision making process. Therefore, a good prepared action plan is necessary. The rationality of decisions included in the plan depends on the quantity and quality of information available to the decision maker. Enterprises, including coal mines, are a set of interdependent phenomena. For that, we need to create decision support tools, the results of which will be visible in the future. Common tools include methods base...

The basis for safety management is the assumption that safe conditions as well as safe behaviour at work do not arise spontaneously, but must be worked out according to a pre-approved program. It is known that preventive actions have a much greater importance and sense than the removing of a damage resulting from accidents. Therefore, it is necessary to take measures aimed at improving the working conditions, equipment and conduct of employees hired in the mine. The presented article is an attempt at a practical a...

It often becomes necessary to evaluate the stress state of the rock massif when developing deposits of solid minerals. Timeous obtaining of data on geomechanical condition of rock massif provides the opportunity to estimate the level of stress and strain fields? development in the mining area and to address the possibility of the occurrence of unfortunate events associated with the rock pressure and gas-dynamic processes. Also, this information offers an opportunity to select effective and safe design schemes and ...

Typomorphic features of placer gold from alluvial deposits of the Bolshaya Kuonamka river basin, draining Eastern framing of the Anabar massif are studied in order to identify association types of primary sources and places, promising for their discovery. Based on identified indicators of gold, it is defined that, ore manifestations of low-sulfide gold-quartz association are the main primary sources of gold-bearing placers. Identification of palladium gold in association with platinoids, as well as its intergrowth...

During the process of conceptual designing of earthmoving or construction boom type machine we have must ensure that it is applicable in practice, meaning stable. Unfortunately, not every time is design of upper structure of such a machine ideal in consideration of position of centre of gravity and that is the reason why are stabilizing outriggers usually attached. This article talks about possibilities of use various schematic drafts of stabilizing outriggers for earthmoving and construction machines on the wheel...

The use of risk analysis methods in evaluating mining landscape. Mining landscape and landscape affected by mining activities is typical for the Moravian-Silesian Region. It is caused by coal mining, which took place on a large amount of territory in the past. Currently the mining is reduced, however, the effects of undermining will continue to persist in the area affected by mining activities. The development of mining is also closely related to the development of industry and industrial production. For evaluatio...

My presentation discusses facts about usage of brickmaking materials necessary for production. I named technological processes for extraction of brickmaking materials reaching to fifties of twentieth century. Their shift in modernization of technological processes in extraction of brickmaking materials and their current state. I concentrated on individual mechanical devices. From first machines serving in help of extraction, transportation and processing which have been entering extraction processes from the begin...

One of the reasons for spontaneous combustion of coal waste dumps is the air intake into the body of a dump. Despite the measures taken to isolate the bases and dump slopes, spontaneous combustion of dumps occur in many countries around the world. That breeds a hypothesis that spontaneous combustion process is facilitated by placement of a dump in the geodynamically active zone of the earth's crust. In geodynamically active zone, due to its high permeability, the interaction of the dumps with environment occurs. P...

The article is devoted to ergatic systems for training skills of handling breathing apparatus (mine self-rescuer) for staff protection in emergency situations. These systems represent hardware-software systems for simulation of physical activity, emergency situations and monitoring the status of a trainee. These tasks are interrelated and must be solved simultaneously in real time to ensure training process. The joint solution of these tasks implies the need to process large amounts of data within short time inter...