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NEW CONSTRUCTIONS OF ARMORED PDC DRILL BITS

A.Ya. Tretyak, E.A. Nirkov, E.V. Sidorova, K.A. Borisov

Objective. The scholarly paper aims to develop the more effective PDC-bit. The selection of the best drilling bit for the specific drilling conditions is one of troubles that oil-and-gas services companies have to face during well construction. Nowadays many different drilling bits being in use for various application well drilling are produced. Now we don’t have an all-purpose rock destruction tool for efficient drilling of any drill ability grade rocks, many specialists and industrial establishments in all the world work to create such drilling tools. Such tools using would help to reduce round-trip operations and as result to improve the drilling speed. The drilling bits cost is about 5% of the well total cost but they are the main ingredient of the well construction economy. 
Method of researches. The known drilling bits designs observing permitted to develop the stabilizing double deck cutting-shearing PDC-bits design calculate the basic technological parameters and describe their work with account of the geomagnetic field influence over the drilling fluid. Results of researches. Research results permitted to create the best stabilizing double deck cutting-shearing PDC - bits design and calculate the basic technological parameters of drilling bits work. Conclusions: 1. The drilling bits design optimization permits to achieve the optimum axial load value and the rational value of unit contact bottom-hole pressure during well boring. 2. In accordance with research of the mechanics of medium and above-average drill ability rocks destruction the bit basic design driving up the well construction efficiency was developed. Recommendation. Authors think, the drilling bits will be multi function in the very near future, in the first place in terms of cutting point-equipping take into account rocks drill ability grade, and certainly subjected to different physical and other fields influence, to improve its strength. Herewith they will be changed structurally, than means, all cutting parts will be movable, field replaceable, hydraulic system will improve and all the hydraulic nozzles will be movable. In this way the drilling speed will grow, the vibration down the hole will lower, borehole cleaning will improve, pressure on the bit will be smoother and as a result the rocks drilling unit cost will be lower.

Number of views: 267

MATHEMATICAL SIMULATION OF WATER DROP MOTION IN VERTICAL SHAFT VENTILATION

A.N. Fomin, S.N. Kuznetsov

The aim of the work is to create a mathematical model of the movement of droplets (particles) in the turbulent air flow in the vertical pipe of the ventilation shaft of the mine (mine). The use of ore (mine) ventilation pipes of different cross-sections allows more efficient and energy-intensive to organize ventilation in the faces. However, the use in the mountain (mine) workings of abundant water irrigation to combat dust and ensure acceptable temperature conditions of people's stay leads to increased humidity (90% – 100%) in the atmosphere of deep mines, which in turn at temperature differences between the bottom-hole horizon and the earth's surface leads to abundant droplet formation and deposition of water masses on the inner surface of the ventilation pipe of the issuing shaft of the mine. Water, flowing down the walls of the pipe, enters the counterflow with the upward flow of exhaust gases, which leads to failures in the ventilation system and emergency situations in the mine ventilation system. In order to understand the process of deposition of droplet liquid in the vertical pipe of the ventilation shaft of the mine (mine), this article presents a corresponding mathematical model of the movement of droplets (particles). The influence of forces acting on the droplets in the upward ventilation flow is considered. Based on Newton's second law, a system of differential equations of the first order is derived and as a result of its solution the trajectories of droplets (particles) in a vertical pipe are obtained by numerical method. The motion graphs of particles (droplets) distributed over the entire section of the pipe, distributed in the boundary layers of the air flow and turbulent zone are presented. The process of subsidence of droplets on the inner wall of the vertical ventilation channel of the outstanding shaft of the mine (mine) is justified and the dependence of the place of subsidence of droplets on their radial location in the plane of the cross-section of the pipe is established.

Number of views: 249

IMPROVING THE STABILITY OF THE FINAL CRATER WHEN CHANGING THE FRACTIONAL COMPOSITION OF PRODUCED ORE

A. S. Kopylov

In the 50-s, prof. K.V. Ruppeneit investigated the mechanism of transfer of rock pressure forces between neighboring individual blocks in a fractured rock mass. Experiments were performed to fill the cracks between the blocks of the array with liquid wax or liquid lead. After cooling of the wax or lead, the rock mass was carefully disassembled in order to extract a “cast” of rock contacts. As a result of many experiments, K.V. Ruppeneit found that the area of directly rocky contacts, namely, the holes in the "casts" - is only 3-4% of the surface of the entire crack between the blocks in the massif. The transfer of pressure forces is carried out through the point contact of the blocks, and basically, the surface of the crack is free from the transfer of pressure forces between the blocks. To determine the necessary stability of the exhaust workings, an assessment was made of the influence of the weight of a column of broken rock mass on their wear. At the same time, the conditions of the necessary strength and stability of the base of the blocks destroyed by the pressure of the weight of the column of the broken rock mass were determined. There are several options for the construction of the base of the blocks: for the release and delivery of PDM ore, trenches and funnels for VDPU and scraper delivery. When ore is released, the contacts of moving pieces of rock with the surface of the funnel are formed only on the surfaces of their contact. The load due to the weight of the column of broken rock does not act on the entire surface of the funnel, but only on the contact points of the pieces of ore with its surface. Therefore, on the basis of physical modeling, the area of rock contacts of pieces of broken rock mass with the surface of the funnel was determined; this ensured a geometric, dynamic and functional similarity to the model in nature, in which the dimensions of the funnels and the fractional composition were observed. With dynamic similarity, the bulk density of ore represented by quartzites and magnetites was observed. In functional modeling, the weight of a column of broken ore with a height of 100 m was observed. Studies were conducted on models made at a scale of 1:50 from full-scale. The area of rock contacts was determined by scanning on the computer the surface of an expanded truncated cone - an expanded funnel of release with dark spots of rock contacts, with a different ratio of fractions in the broken rock mass. Further, using a computer, their absolute and relative area was de-termined. Since the base of the block is an array cut by outlet funnels having inclined lateral surfaces to the horizon, as is known, there is also a force acting on the shearing (shear) of rocks by the weight of a column of broken rock mass. It was necessary to determine which of the above forces exerts the greatest destructive effect on the base of the block during the mining of rock mass, and based on this information, determine the permissible height of the beaten out ore layer during mining of the ore deposit. Calculations were made of the solid base of the block under the action of crushing and shearing forces, from which it was revealed that when pieces of broken ore act on the inclined surface of the outlet funnel, the destruction of the surface of the funnel occurs primarily due to the shearing component of the column weight forces of the broken rock mass. Calculations show that the column of rock mass creates a shearing force, 2.1 times higher than when crushed. Further, similarly, the calculations of the effect of crushing and shearing forces on the weight of a column of broken rock mass for various sizes of funnels were made. Based on the calculations, the dependence of the permissible maximum output volume of the rock mass on the value of the coefficient of rock contacts was established. For mining syst

Number of views: 192

INFLUENCE OF MINE WATERS TO THE STATE OF THE ENVIRONMENT IN THE EASTERN DONBASS

Gavrishin

Purpose. The aim of the research is to identify the main regularities of formation of chemical composition of mine waters in the Eastern Donbass for the 100-year period and to assess their role in contamination of ground and surface waters in the region. Methods of researches. Interpretation of the data using the standard methods of mathematical-statistical analysis of information and original digital computer technology of classification of multivariate observations AGATE-2 (G-method). This technology allows you to highlight similar taxa in the absence of a priori information (task without a teacher), use dependent signs, high light taxa at various levels, to assess the similarity between taxa and informative signs. Results of researches. The coal industry has a significant impact on the environmental status in the Eastern Donbass. A detailed analysis of the chemical composition of mine water to nine time intervals for the 100-year period showed that the process of personnel changes is undulating in nature. The intensification of the processes of oxidation, leaching and dissolving discovered after periods of flooding of mines (in the post-war 40-e-50-IES and after the Elimination of mines in the 90-ies). It is in these times of mine waters most intensely polluting natural waters in the region, there is a sharp increase in salinity and especially sulphate iron and various metals. Takeaway mine waters on the surface of the solute reaches 413 thousand tons/year. Four main types of (direction) changes the chemical composition of mine waters. The genesis of the first type is associated with the influence of intensive processes of oxidation of sulfides and sulfur contained in coals and enclosing rocks. The second type is caused by the weakening of the oxidation and the beginning of the influx of chloride in ground-condensation from water-carbon phase. There is a possibility of detection within East Donets Basin oil and gas fields, particularly in Gukovo-Zverevskom coal area. Summary. Found that the mine waters are the leading factor in negative impacts on our environment and cause serious environmental damage in the territory of the Eastern Donbass. This calls for effective measures for the rehabilitation of environmental conditions and improvement of remediation technologies.

Number of views: 219

A MATHEMATICAL MODEL FOR ESTIMATING TECHNOGENIC LOSSES FROM THE OPERATION OF MINING ENTERPRISES

Yu.S. Petrov, A.A. Sokolov, E.V. Raus

The aim of the article is to develop a mathematical model of technological damage to the functioning of mining enterprises to improve the monitoring of technological cycles. The study of technological processes of industrial enterprises is accompanied by the emergence of man-made cycles.
Research мethods. In almost any existing technological system, in particular, a mining enterprise, in addition to the current tech-nogenic influence, the accumulated man-made damage already existing at the given moment can be distinguished. For example, pollution of soil and water bodies with various harmful substances as a result of constantly and periodically (emissions) of existing sources of pollution already takes place at this moment and continues to increase due to the continuous operation of pollution sources. In the work, the function of accumulated damage for the material-mathematical model of the technogenic cycle of a mining and metallurgical enterprise is proposed and investigated. The model developed on the basis of equations of electrohydrodynamic analogy allows us to adequately reflect the sequence of stages of environmental impacts during research, which increases the information content of the information support system for monitoring the technogenic cycle of a mining and metallurgical enterprise. The results of the study. With the development of a mathematical model that allows one to determine the accumulated man-made damage in the system of sustainable development of mountainous areas, new perspectives are opened for the analysis of the man-made impact of mining and metallurgical enterprises on the environment and the possibility of making forecasts of the occurrence of man-made disasters. The proposed software allows one to assess the sustainable development of regional economic complexes in any regions of the Russian Federation based on the introduction of specific characteristics for the studied region in the database. The scientific provisions described in the article can be used to analyze technogenic cycles not only in the mining and metallurgical industry of the Russian Federation, but also in any other economic industry where technogenic manifestations of a different nature take place. The introduction of the developed information systems, methods and models in the mining and metallurgical industry of the Russian Federation will increase management efficiency, significantly reducing the technogenic load in the system “enterprise of the mining and metallurgical complex - environment”. Findings. Development and application of mathematical models of the ecological state of the environment, possible environmental damage, etc. they will help to reliably assess the environmental situation, make correct forecasts, outline and implement ways to reduce the anthropogenic load on the environment.

Number of views: 237

STRATA MOVEMENT WHEN EXTRACTING THICK AND GENTLY INCLINED COAL SEAM FROM A PHYSICAL MODELLING ANALYSIS: A CASE STUDY OF KHE CHAM BASIN, VIETNAM

Quang Phuc Le, Tien Dung Le, Duc Thang Pham, Anh Tuan Nguyen

Quang Ninh coalfield over the years has witnessed geotechnical issues such as surface subsidence and strata caving, deformation and fracture due to the underground coal mining. 
These issues have been preliminarily investigated mostly by using field observation. 
The corresponding solutions and measures, however, seem to be inactive and perfunctory. This paper presents an analysis of height of strata caving, evolvement of deformation and movement zone, caving angle in strike direction, surface subsidence and strata movement when mining thick-gently inclined and/or closely distributed coal seams by using a physical model based on a case study of Khe Cham basin, Quang Ninh coalfield, Vietnam. The model shows that roof strata cave cyclically with a height being 5-6 times mining height; caving angle ranges from 64 to 67 degrees; maximum subsidence magnitude stabilises around 1.5 m; and strata behaviour caused by the mining of lower seam is less severe as that of the upper seam. The paper’s findings are useful for engineers to better plan and design technical solutions to improving safety in thick coal seam extraction.

Number of views: 230

ECOLOGY AND ENERGY SAVING AT MINING ENTERPRISES USING PROTECTIVE DEVICES

S.Ya. Davydov, N.G. Valiev, N.V. Grevtsev, L.N. Oleinikova

One of the common ways to deal with unproductive losses of raw materials and atmospheric pollution from technological baths of electrolysis production is aspiration. Ensuring sanitary conditions in the workplace due to only aspiration is difficult due to a sharp increase in the volume of exchange ventilation. The use of airborne suction is accompanied by the entrainment of the electrolyte in the form of a droplet liquid and steam. Heat losses during electrolytic refining of copper in the traditional version reach 70 - 80%. In order to reduce the release of carcinogenic aerosols into the atmosphere, a foam protective layer is created on the surface of the electrolyte. The disadvantage of this method is the low efficiency of protection, the instability of the foam layer, its explosiveness and toxicity of some blowing agents. Placing floats on the bathtub mirror also allows you to close the bathtub mirror. The company refused to use this method due to the inconvenience of servicing electrolysis baths. When caring for the hardening concrete mixture, it is necessary to ensure optimal thermal and humidity conditions, on the observance of which the normal increase in the strength of the material depends. To create a warm environment and to intensify hardening of concrete, work is carried out in light temporary buildings-heaters or under film coatings. In the latter case, the concrete is covered with a vaporwaterproof film and kept in such a closed volume until the design or critical, relative to moisture loss, strength is set. The calculated dependences of determining the thickness of the film coating, tensile strength and elongation at break are presented. Physical-mechanical and electrical characteristics of a plastic film are presented. A description of the design features and operation of the new drive shelter device is given.

Number of views: 408

BASSIN TOURIST CLUSTERS OF THE ALTAYA OUTSKIRTS

V.S. Revyakin, A.N. Dunets, Yu.V. Kozyreva

Due to growth of interest in tourism, in recent years in the Altay territory  several zones of the increased concentration of tourist objects are formed caused by river basins and orographical barriers. The territorial tourist and recreational cluster − group of geographically adjoining interacting companies, public organizations and the related state bodies forming and serving tourist streams and territories using recreational potential. Feature of emergence of such cluster is need of creation of technological communications between the enterprises and sectors of economy participating both in production, and in realization of tourist's products. According to the orogidrografichesky system of a northern macroslope of the Altai highland it is possible to speak about the system of basin tourist clusters. Each of them has unique features with existence of the dominating objects which at the organization of binding routes allow to provide in the long term sustainable development of branch of tourism, a recreation and treatment. The documents of territorial planning developed in recent years poorly are used in expeditious practice. The expediency of their updating and careful study taking into account quickly changing picture of land use, emergence of the new especially protected territories, environments of the domestic and international market of tourist services is undoubted.

Number of views: 307

ASSESSMENT OF THE INFLUENCE OF CLIMATE CHANGE ON SNOW-ICE RESOURCES AND HYDROLOGY OF MOUNTAIN PAMIR RIVERS

P.I. Normatov, R. Armstrong, I.Sh. Normatov

The research object. The proposed article considers the climatic features, the state of the ice and snow cover of the mountainous Pamir as a source of food for numerous rivers and the climate-forming link in the region of Central Asia. Goal. To analyze the processes in the Pamir’s mountain ecosystem regarding snow-ice and water aspects in the spectrum of changes occurring on a planetary scale. To establish the influence of mountain orography on the distribution of air masses and the formation of snow cover, the change in the river hydrograph due to changes in the current state of the climatic factors of the mountain river basin. Methodology. The analysis of the snow-ice resources state of the Pamir was carried out based on extensive use of archival and modern data using statistical classification to establish the dynamics of their changes in climate warming conditions. A comparative assessment of changes in the hydrology of the Pamir rivers was carried out by comparing modern hydrological characteristics with the early period. Results. Analysis of the glaciers and snow cover state in the mountains of several countries showed that climate change makes significant adjustments in the functioning of many components of the ecosystem, and especially in reducing the area of glaciation and glacier degradation. The studies results of the climate change impact on the snow-ice resources of the mountainous Pamir using the example of the upper reaches of the Trans boundary Pyanj River show a significant impact of mountain orography on precipitation and the formation of snow cover. Conclusion. A deep analysis of the published works on the effects of global climate change on the snow-ice resources of high mountains demonstrated that the mountain ecosystem is particularly sensitive to climate cataclysms. The heterogeneity of the spatial distribution of precipitation and the depth of snow cover in the Pamir in three climatic zones upstream of the Pyanj River is noted. The western climatic zone of the Pamir is characterized by more abundant precipitation than the eastern zone. It is assumed that the decreasing trend of precipitation is due to the fact that the eastern part is subject to the inflow of dry mass. The mass of the air of the Indian Monsoon is unloaded when passing high mountain ranges and only dry residue enters the eastern part of the upper reaches of the Pyanj River. The impact of climate change on water flow is analyzed using the example of the water content of the Vanch – tributary of the Pyanj River, and a comparison of the water volume values of the Vanch River in two periods (1940–1970 and 1986–2016) revealed its increase over the period 1986–2016.

Number of views: 354

A MORPHOTECTONIC SURVEY ON GOLPAYEGAN WATERSHED USING AHP METHOD IN GIS ENVIRONMENT

Davood Birjandi, Reza Derakhshani, Shahram Shafiei Bafti, Hamed Chatrouz

Spatial variation of tectonic activity along Golpayegan drainage basin in Iran are assessed using morphometric approaches by taking advantages of Geographical Information System, GIS. The Golpayegan region is located in the central part of SanandajSirjan metamorphic zone, SSMZ, of Iran, where is affected by Iranian – Arabian continental plate collision. The quantitative study of morphometric indices allows to compare geomorphic features and to zoning out and interpret the intensity of active tectonics. In this research, some morphometric indices such as Sinuosity of Mountain Fronts (Smf), Faceting of mountain fronts (Facet), Valley floor index (Vf) and valley ratio index (V ratio) is surveyed to be able to zone out the tectonic activity level in the water basin of   Golpayegan taking advantages of fuzzy AHP method in the GIS environment.

Number of views: 394
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ISSN 1998-4502 (Print)                                                            ISSN 2499-975Х (Online)