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Facilities and technical systems used in coal mines have limited durability. This is the result of very difficult conditions in which they are used. In particular it applies to environmental conditions and not entirely predictable load states of these facilities. Mining machines and devices are also exposed to various types of hazards, which in many cases significantly reduce their durability. For this reason, it is very important to properly use them and supervise and monitor their work. In this respect, huge res...

The hazard of tecnogenous earthquakes caused by mining of mineral deposits is increased if they occur at economically developed regions with ecologically dangerous objects. A deep coal mine of the Sinvay deposite in China is an example when seismicity due to mining was an important factor influencing both the mining conditions and ecological environment. At a more than 1000m mining depth the power of rock bursts rose to 107 J and they manifested themselves as minor earthquakes on the earth surface. The increasing ...

Calculation of the mining support in tunnels and/or underground facilities can be based on application of contemporary numerical methods, but sometimes it can be performed with the classical methods too. These methods can be found to be used in order to choose variants and ways of supporting, but also in the moments that unpredictably appears during the construction of facility. Before installing a permanent mining support, these methods can help the projector at the selection of type of support and ways of tempor...

The former village Rosiuta, now neighborhood of Motru city, located in Motru mining basin, is surrounded by sterile waste dumps and lignite storage platforms. These are a constant source of particulate matter which is carried by the wind over the inhabited area and affects the quality of breathing air. In order to evaluate the powders dispersion from these sources, it was made chemical and granulometric analysis of the particulate matter on several material samples collected from the area. Based on various meteoro...

The paper presents the results of theoretical and practical research on developing the infrastructure for assessment of overall risk (explosion / occupational terrorist attack) associated with unwanted events such as major accidents that can occur at explosive storehouses for civilian use. The scientific research outlined in this article was carried out within the NUCLEU Project PN 16 43 02 15 - ?Research on increasing safety levels at technical facilities for storage of explosives for civil use?. The key element ...

The planned maintenance activities of the mining technological equipment are carried out on the principles of risk management and is done in order to prolong their duration of operation and to reduce the production cost. The quick possibilities of reducing production losses due to accidental stoppages of quarries and underground exploitation equipment, depend on the establishment and application of reconditioning methods of the subassemblies and spare parts that are frequently defects and replacement. The rotary a...

The rocks exploited in quarries have certain physical, mechanical and technological characteristics that favors the intense wear, especially by abrasion of the active surfaces of the subassemblies of the technological equipment. Some spare parts and subassemblies are subject to similar wear phenomena, as is the case with the excavators bucket teeth in the lignite pits and the loaders cup teeth in the basalt pits. In the case of the basalt aggregates which are the main raw material needed for the development of the...

Under intense stress, energy consumption undergoes essential changes that largely depend on functional characteristics of the respiratory system, which in turn are in close correlation with the body?s training degree and physical demand. During a pronounced dynamic effort, there is a progressive decrease in blood oxygen saturation and an increase of pulse. Cardiac rhythm is a physiological parameter commonly used in telemonitoring as it allows the assessment of rescuer?s general condition, heart rhythm disorders b...

In the combustion processes the nature and concentration of the developed gaseous effluents depends on the type of materials that are subject to combustion as well as on the conditions in which the oxidation processes take place. The purpose of this paper is the experimental determination of the combustion parameters and the study of the developed gaseous effluents from several combustible materials. The production of gaseous products resulting from combustion results in different yields depending on several param...

The decisive factor in the process of under pressure networks inspection is determined by the correct choice of the control method in order to observe with great attention the possible faults caused by the physical wear and tear resulting from the long use. Emphasis is placed on safety conditions of under pressure equipment, which include mandatory minimum technical requirements for periodic checking of under pressure networks for pressurized, liquefied or dissolved gas. Defectoscopy is a set of procedures used to...

Protecting human labors process seeks to eliminate and/or reduce the potential causes of injury and disease in order to achieve full control of risks from hazards associated. With all the technical progress and technology in most industries, and especially in the oil and natural gas, there are failures with casualty and property damage. For this reason, it is indispensable the presence of the special intervention and rescue teams to limit/ liquidation, failure that generates explosive atmosphere and/or toxic and r...

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 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...

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...