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Date submitted2022-09-30
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Date accepted2023-04-03
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Date published2024-02-29
Optimization of the location of a multilateral well in a thin oil rim, complicated by the presence of an extensive gas cap
- Authors:
- Кirill О. Тomskii
- Mariya S. Ivanova
The specific share of the reserves of hard-to-recover hydrocarbon raw materials is steadily growing. The search for technologies to increase the hydrocarbon recovery factor is one of the most urgent tasks facing the oil and gas industry. One of the methods to expand the coverage of oil reserves and increase oil recovery is to use the technology of drilling multilateral wells with a fishbone trajectory. In the Russian Federation, the most branched well was drilled in the Republic of Sakha (Yakutia) at the Srednebotuobinskoye oil and gas condensate field. The main object of development is the Botuobinsky horizon (Bt reservoir). About 75 % of the geological reserves of the reservoir are concentrated in a thin oil rim with an average oil-saturated layer thickness of 10 m with an extensive gas cap. This circumstance is one of the main complicating factors in the development of the Srednebotuobinskoye oil and gas condensate field. For such complex wells, one of the most important design stages is to determine the optimal location of the fishbone well in an oil-saturated reservoir. The article shows the results of sector modeling in the conditions of the Srednebotuobinskoye field to determine the optimal location of multilateral wells using Tempest simulator.
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Date submitted2022-05-26
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Date accepted2022-11-17
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Date published2022-12-29
Renovation method of restoring well productivity using wavefields
A stagewise theoretical substantiation of the renovation vibrowave method of influencing the near-wellbore zone of reservoir for restoring well productivity is presented. The area of treatment by the proposed method covers the reservoir with a heterogeneous permeability with fractures formed by fracking. In this method a decrease in concentration of colmatants occurs due to a change in direction of contaminants migration. Under the influence of pressure pulses, they move deep into the reservoir and disperse through the proppant pack. The results of mathematical modelling of the propagation of pressure wave and velocity wave and the calculations of particles entrainment in wave motion are presented.
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Date submitted2021-07-05
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Date accepted2022-11-17
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Date published2022-12-29
Determination of suitable distance between methane drainage stations in Tabas mechanized coal mine (Iran) based on theoretical calculations and field investigation
A large amount of gas is emitted during underground mining processes, so mining productivity decreases and safety risks increase. Efficient methane drainage from the coal seam and surrounding rocks in underground mines not only improves safety but also leads to higher productivity. Methane drainage must be performed when the ventilation air cannot dilute the methane emissions in the mine to a level below the allowed limits. The cross-measure borehole method is one of the methane drainage methods that involves drilling boreholes from the tailgate roadway to an un-stressed zone in the roof or floor stratum of a mined seam. This is the main method used in Tabas coal mine N 1. One of the effective parameters in this method is the distance between methane drainage stations, which has a direct effect on the length of boreholes required for drainage. This study was based on the measurement of ventilation air methane by methane sensors and anemometers placed at the longwall panel as well as measuring the amount of methane drainage. Moreover, in this study, the obtained and analyzed data were used to determine the suitable distance between methane drainage stations based on the cross-measure borehole method. In a field test, three borehole arrangements with different station distances in Panel E4 of Tabas coal mine N 1 were investigated. Then, the amounts of gas drained from these arrangements were compared with each other. The highest methane drainage efficiency was achieved for distances in the range of 9-12 m between methane drainage stations.
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Date submitted2021-03-23
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Date accepted2022-01-24
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Date published2022-04-29
Justification of the technological scheme parameters for the development of flooded deposits of construction sand
- Authors:
- Vladimir V. Ivanov
- Denis O. Dzyurich
The article describes the main types of technological schemes for working out the flooded strata of sand deposits using hydraulic shovel excavators. The analysis of scientific and technical literature describing the experience of using hydraulic shovel excavators in the open-pit mining, including pits for the extraction of construction sand, has been carried out. The proposed technological scheme is that the development of reserves of the flooded strata without preliminary water reduction is carried out by a hydraulic shovel excavator from under water by a downward digging with the storage of the extracted rock mass in bulk (for dewatering), placed in such a way that when working out the next mining bench width, it is located within the working area of the excavator for simultaneous processing of the next bench width and loading of dewatered sand from the pile. Calculations of the parameters of the operating platform and the excavator block of the proposed technological scheme for conducting open-pit mining were carried out. The dependence for determining the minimum length of the mining operations front of an excavator for drawing up a technological scheme of operation of a backhoe hydraulic excavator on working out the flooded strata with the pile formation for dewatering sand and its subsequent uploading from the pile by the same excavator is presented.
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Date submitted2021-06-24
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Date accepted2021-10-18
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Date published2021-12-16
Modeling the acid treatment of a polymictic reservoir
- Authors:
- Mars M. Khasanov
- Andrey А. Maltcev
Acid treatment of wells program is directly related to oil production efficiency. Investigations aimed at improving the efficiency of acid treatment in a terrigenous reservoir have mainly reviewed the changing and adapting the reagents to minimize bridging caused by acid-rock interaction. Under real conditions, application of new and unique acid compositions is a complex process from an organizational point of view and is therefore not widely used as compared with conventional compositions based on a mixture of hydrochloric and hydrofluoric acids. The paper is based on an approach to improve acid treatment efficiency through optimal design based on near-bottomhole zone treatment simulation. The aspects for practical application of the developed acid treatment simulator for terrigenous reservoirs based on a numerical model of hydrodynamic, physical and chemical processes in a porous medium on an unstructured PEBI-grid are described. The basic uncertainties of the model are identified and analyzed. Influence of empirical parameters within the system of equations on the calculation results and modeling of the mineralogical composition of rocks are considered. Algorithm for static modelling of near-bottomhole zone for acid treatment modelling is described, as well as an approach to optimizing the design of near-bottomhole zone treatment based on adapting the results of rock tests in the model. Using experimental data, the necessity of accounting for influence of secondary and tertiary reactions on the results of modeling physical and chemical processes during acid treatment of terrigenous reservoirs was proved. The distinctive features of West Siberian objects (polymictic reservoirs) with respect to the efficiency of near-bottomhole zone treatment with clay acid have been investigated. Series of calculations to determine the optimum volume of acid injection has been carried out. Experience of previously conducted measures under the considered conditions has been analyzed and recommendations to improve the efficiency of acid treatment have been given.
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Date submitted2020-09-09
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Date accepted2021-03-29
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Date published2021-09-20
Developing features of the near-bottomhole zones in productive formations at fields with high gas saturation of formation oil
The article studies the formation features of the bottomhole zones in productive formations during operation of production wells in the north of the Perm Territory. Their distinctive feature is the high gas saturation of formation oil. The most widely used parameter in Russian and world practice – the skin factor was used as a criterion characterizing the state of the bottomhole zone. Analysis of scientific publications has shown that one of the main problems of applying the skin factor to assess the state of bottomhole zones is the ambiguity of interpretations of its physical meaning and the impossibility of identifying the prevailing factors that form its value. The paper proposes an approach to identifying such factors in the conditions of the fields under consideration, based on multivariate correlation-regression analysis. Choice of this tool is due to the complexity of the processes occurring in the “formation – bottomhole zone – well” system. When describing complex multifactorial processes, the chosen method demonstrates a high degree of reliability. For a large number of wells in the region, significant material was collected and summarized, including the results of determining the skin factor (1102 values) during hydrodynamic investigations, as well as data on the values of various geological and technological indicators, which can probably be statistically related to the value of the skin factor. A series of multidimensional mathematical models has been built; the skin factor was used as a predicted parameter, and data on the values of geological and technological indicators were used as independent indicators. Analysis of the constructed models is a key stage of this study. Set of parameters included in the multidimensional models, sequence of their inclusion and contribution to the total value of the achieved determination coefficient as the main indicator for the performance of the constructed models were studied. It has been established that the main factor influencing the state of the bottomhole zone is oil degassing. Significant differences in the formation features of the skin factor in the terrigenous and carbonate sediments at the fields under consideration have been determined.
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Date submitted2019-09-25
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Date accepted2019-12-20
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Date published2020-04-24
Study of the well near-bottomhole zone permeability during treatment by process fluids
- Authors:
- Evgenii A. Rogov
In the process of drilling-in productive horizons, several irreversible physical and chemical processes take place in the near-wellbore zone of the formation: stress state of the rocks changes, penetration of the filtrate and solid phase, as well as drilling mud into the reservoir, and swelling of clay particles of intergranular cementing material are observed. As a result, permeability of productive horizon is significantly reduced and, consequently, potential inflow of oil or gas from formation is excluded. An equally serious problem exists during well servicing and workover, when the use of irrational fluids of well killing causes negative consequences associated with deterioration of reservoir properties of formations in the wells being repaired. Article presents the results of the experiments on permeability of clayed porous samples after exposure to various compositions of liquids. In order to increase permeability of near-borehole zone of the formation and increase productivity of wells completed by drilling, and after well servicing and workover, a composition of the process fluid containing a 15 % aqueous solution of oxyethylene diphosphonic acid (OEDA) with addition of a surfactant is proposed.
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Date submitted2019-10-30
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Date accepted2019-11-23
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Date published2020-02-25
Methodology for determining the parameters of drilling mode for directional straight sections of well using screw downhole motors
- Authors:
- Vladimir S. Litvinenko
- M. V. Dvoinikov
Article presents results of study on possibility of increasing the efficiency of drilling directional straight sections of wells using screw downhole motors (SDM) with a combined method of drilling with rotation of drilling string (DS). Goal is to ensure steady-state operation of SDM with simultaneous rotation of DS by reducing the amplitude of oscillations with adjusting the parameters of drilling mode on the basis of mathematical modeling for SDM – DS system. Results of experimental study on determination of extrema distribution of lateral and axial oscillations of SDM frame depending on geometrical parameters of gerotor mechanism and modes ensuring stable operation are presented. Approaches to development of a mathematical model and methodology are conceptually outlined that allow determining the range of self-oscillations for SDM – DS system and boundaries of rotational and translational wave perturbations for a heterogeneous rod with an installed SDM at drilling directional straight sections of well. This mathematical model of SDM – DS system's dynamics makes it possible to predict optimal parameters of directional drilling mode that ensure stable operation of borehole assembly.
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Date submitted2019-07-10
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Date accepted2019-08-30
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Date published2019-12-24
Methodology for calculating technical efficiency of power sections in small-sized screw downhole motors for the «Perfobur» system
With an increase in the share of old and low-yield wells and for the efficient exploitation of fields, it is necessary to include low-capacity formations into production. There are many wells where sidetracking and hydraulic fracturing are difficult due to the close proximity of the gas cap and underlying water caused by geological and technological reasons, and the use of existing secondary drilling-in technologies is not effective due to the extensive colmatated zone or annular circulation. Relevance of radial drilling technologies is growing, which allows drilling-in of the formation with a network of extended channels to establish high-quality hydraulic communication between the formation and the well without affecting the permeability of the formation. In contrast to radial drilling technologies using hydraulic washing, technical system (TS) «Perfobur» uses small-sized screw downhole motors (SDM) and rock cutting tools for channel construction. For efficient milling of production casing and destruction of rock, the hydraulic downhole motor must have high torque, and for the possibility of drilling with a high rate of angle gain, it must have short power section. Existing Russian and foreign SDM have limited number of standard sizes and do not meet the requirements specified for the development of the downhole module of TS «Perfobur». The paper discusses the development of universal small-sized sectional screw downhole motors for milling casing strings and drilling a network of branched channels of super-small diameter and radius of curvature as a part of the TS «Perfobur». Methodology proposed in the article for selecting optimal configuration of the SDM power sections allows constructing small-sized sectional downhole motor that meets the technical requirements and has improved characteristics compared to standard SDM.
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Date submitted2019-05-05
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Date accepted2019-07-03
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Date published2019-10-23
Scraper Face Conveyors Dynamic Load Control
- Authors:
- E. K. Eshchin
The task of controlling the dynamic loading of scraper face conveyors (SC) is considered and the unsatisfactory state of loading of mechanical and electrical components of the SC is recorded. The possibility of the appearance of a self-oscillatory nature of the entire system load due to the peculiarities of the movement of the traction chain along the lattice frame of the SC is indicated. The property of the system is noted – the cyclic nature of the loading of the circuit during movement, which causes energy exchange processes between the mechanical and electromotive components of the conveyor (when using the head and tail electric drives) through the common cable network of the power supply system of the SC. A high level of dynamic loading of the electromechanical system causes the problem of eliminating the self-oscillating operating mode of the SC that generates it which is proposed to be solved by changing the angular rotation speeds of the SC drive sprockets. Angular speeds can be changed by applying frequency control of asynchronous electric motors. The efficiency of setting the frequency of electric motor stator currents of the head and tail drives of the conveyor is established in proportion to the frequency of rotors rotation to eliminate self- oscillating modes of operation in the main operating mode. The possibility of reducing the starting shock values of the electromagnetic moments of electric motors is considered. The results of the calculation of the start-up and liquidation of the self-oscillating operating mode are presented on the example of the scraper face conveyor Anzhera-34. The results of calculations of the start-up modes and the main operational transportation of coal in an uncontrolled mode of operation and after the introduction of control are compared, based on which it is concluded that it is advisable to use active control of the dynamic loading ofSC.
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Date submitted2019-03-21
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Date accepted2019-05-05
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Date published2019-08-23
Stimulation of the Drilling Process with the Top Driven Screw Downhole Motor
- Authors:
- S. L. Simonyants
- M. Al Taee
Paper considers application of the top driven screw downhole motor during drilling of directional wells. The advantages and disadvantages of the rotation-sliding technology with implementation of top drive together with screw downhole motor are shown. It has been proven that the use of a screw downhole motor with simultaneous rotation of drilling pipes using the drilling rig's top drive allows increasing the bit rotation frequency without additional loading of the drilling string. Field data for the work out of one-type PDC bits in identical geological and technical conditions with different types of drives during the construction of three directed wells at the Rumaila oil field of the Republic of Iraq were obtained. A regular increase in the mechanical penetration rate, which is explained by an increase in the bit rotation frequency, has been proved. According to the data obtained, a comparative analysis of the drilling indices was carried out, as a result of which the feasibility of joint use of top power drive with screw downhole motor at drilling oil and gas wells was proved.
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Date submitted2018-09-07
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Date accepted2018-11-10
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Date published2019-02-22
Justification of the technological parameters choice for well drilling by rotary steerable systems
- Authors:
- Vladimir S. Litvinenko
- M. V. Dvoinikov
Paper presents the analysis of the investigation results of vibrational accelerations and beating amplitudes of the downhole drilling motor, which help to define the ranges of optimum energy characteristics of the gerotor mechanism, ensuring its stable operation. Dependencies describing the operation of the «drilling bit – rotary steerable system with power screw section – drilling string» system and the values of the self-oscillation boundaries and the onset of system resonance when it is used jointly, were defined as a result of computational and full-scale experimental research. A mathematical model is proposed, which allows determining the optimal range of technological parameters for well drilling, reducing the extreme vibration accelerations of the bottomhole assembly by controlling the torque-power and frequency characteristics of the drilling string, taking into account the energy characteristics of the power screw section of the rotary steerable system. Recommendations on the choice of drilling mode parameters were given.
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Date submitted2018-01-17
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Date accepted2018-03-09
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Date published2018-06-22
Control and regulation of the hydrochloric acid treatment of the bottomhole zone based on field-geological data
- Authors:
- M. K. Rogachev
- V. V. Mukhametshin
The analysis results of the hydrochloric acid treatment of the bottomhole zone efficiency along the deposits of high-viscosity oil in the carbonate reservoirs of the Tournaisian stage are presented in the paper. Based on the use of the non-parametric Kulbak criterion, the most informative geological and technological parameters, which affect most the success of hydrochloric acid treatments, assessed by the criteria of increased oil production and reduced water cut, are revealed. The generalization of the hydrochloric acid treatments experience in the conditions of the high-viscosity oil reservoirs of the Tournaisian Stage allows for efficient forecasting, selection of wells, control and regulation of the treatment process to reduce the number of inefficient operations and improve the technical and economic parameters of fuel and energy enterprises at the investigated sites and the ones with similar field-geological characteristics.
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Date submitted2016-09-01
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Date accepted2016-11-05
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Date published2017-02-22
Research on technical and technological parameters of inclined drilling
- Authors:
- M. V. Dvoinikov
An analysis of operational capabilities of inclined drilling equipment and technology is presented. Two options of rotary drilling are reviewed as technical and technological solutions, facilitating construction of wells with difficult profiles. The first option implies that the driver unit of the drill bit is represented by downhole drilling motor, the second one utilizes sophisticated rotary steerable systems. Practical results of drilling wells with difficult profiles are presented. A quality assessment of drilling is provided through the example of comparing designed and actual trajectories, using different driver units for the drill bit, as well as properties of surrounding rocks, rheology of the drill fluid and other characteristics of dynamically active systems. A range of rotation speed has been determined that allows rotary steerable systems to have minimal oscillation amplitude of the bottom-hole assembly. Analysis of investigation results showed that the main source of oscillations is linked to bending and compressing stresses, caused by well deviations as well as rigidity of the drilling tool. In effect, in the bottom-hole assembly occur auto-oscillations, making it impossible to correct azimuth and zenith angles. Alteration of rigidity in the bottom part of the tool and drilling parameters, implying reduced rotation speed of the drill string and regulation of drill bit pressure, can partially solve this problem, though increase in rotation speed is limited by technical characteristics of existing top drive systems.
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Date submitted2015-08-26
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Date accepted2015-10-16
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Date published2016-04-22
Reserch of modernized perforator-hammer for drifting special roadway the underground mines «Metrostroy»
- Authors:
- D. A. Yungmeister
The article describes the design of modernized hammer-perforators for tunnel complexes for construction of auxiliary mine workings of «Metrostroi», St Petersburg, protected by patents. The article deals with assembly variants of the executive device of percussion type for breaking faces of complicated structure. Particular attention is paid to hammers working in the mode of the «counter-shearing» accomplished by dual jackhammers. The results of experimental tests to determine pike penetration into rock array for different values of rock hardness and pressing force. It is noted that the proposed solution replaces manual labor, reduces working cycle time.
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Date submitted2015-08-03
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Date accepted2015-10-06
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Date published2016-04-22
Technical and technological solutions to ensure stability of downhole drilling motors
- Authors:
- M. V. Dvoinikov
- Yu. D. Muraev
The article shows research analysis of engineering and technological solutions that aimed at improving the efficiency of drilling wells using optimization of dynamic of work downhole drill-ing motors. As the technical solutions that reduce vibration, considered two options of construc-tion of the power section. A first embodiment involves the production of a hollow rotor which can reduce its moment of inertia. The second solution is the production of modular rotor, which are changing the eccentricity (misalignment) of rotating parts of the engine. The research of fluctuations throughout the length of the power section of the working bodies and the spindle of the engine, taking into account changes in its energy characteristics has been con-ducted to ensure stable operation of the engine in a well, identifying optimal loading parameters. Indicators of shaft speed ensuring minimum vibration amplitude of the engine has been Iden-tified. Optimal speed range of the rotor to prevent buckling of the BHA and to sustain its operation is shown to be between 15-20 % of the frequency of the engine at idle. The maximum reduction in speed during the drilling process should not exceed 30 % by conducted research.
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Date submitted2015-07-16
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Date accepted2015-09-26
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Date published2016-02-24
External dynamics formation in mining machines
- Authors:
- E. A. Zagrivnyi
- G. G. Basin
This study surveyed the current state of mining machines dynamics. In the significant number of theoretical studies mining face was represented as a force variable in time. Such face representa-tion does not reflect physical reality, and does not include the influence of mining machines dynamic parameters and processes on face formation. This paper introduces a new dynamic model of the mining machine with an idealized damageable face, which provides kinematic excitation of the drill-ing bit while moving on its trail. In this case, the mining machine is represented as a dynamic system with a delay (a system with «memory»), where face coordinates depend on the dynamic parameters and operating modes. The proposed system was checked for stability. This study shows that stable dynamic systems «executive body» with a variable structure provide minimal target dynamic loads. Experimental study of executive bodies suspensions of the blasthole drilling rigs, coal mining and tunneling machines was conducted. Experiments showed high efficiency reduction of dynamic loads in the carrying systems in all cases.
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Date submitted2014-11-04
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Date accepted2015-01-20
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Date published2015-10-26
Stability of productive well operation in a steam hydrothermal field
- Authors:
- A. N. Shulyupin
A condition of well operation stability based on agreement of indicator characteristics of well and aquifer throughput capacity is considered. Two hypotheses of the stability state are examined: with one and two possible combinations of characteristics. It is shown that taking into account resistance between the wellhead and the environment with constant pressure helps explain all the features of wellhead pressure and flow-rate relationship of steam-water wells based on the hypothesis with one combination (when the operating point is located on the ascending branch of a well characteristic). The throttling effect on the wellhead which was used in the development of the Mutnovka steam hydrothermal field in order to stabilize the well operation is explained.
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Date submitted2013-07-25
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Date accepted2013-09-29
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Date published2014-03-17
Assessment of the longwall face length influence on gas emission at longwall panels of the OJSC «Vorkutaugol» coal mines
- Authors:
- O. I. Kazanin
- A. M. Sufiyarov
Results of researches of the longwall face length influence on gas emission at the coal seam «Chetverty» longwall panels of the OJSC «Vorkutaugol» mines are given. Dependences of the longwall production and longwall face length are specified. Range of rational values of the longwall face length according to the gas emission control efficiency is determined.
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Date submitted2009-10-04
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Date accepted2009-12-19
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Date published2010-09-22
Modeling of the volumetric stress-strain condition of the rock massive in the near mine which are crossing zone of weakening
- Authors:
- A. G. Protosenya
- D. N. Petrov
- M. G. Popov
According to geological data which was received at the Yakovlevsky deposit, the volumetric model was developed. This model taking into consideration the driving of the mine through zone of weakening. During the analysis of the stress-strain condition near the mine the character of distribution and numerical results of tangential and longitudinal stresses have been revealed. The zone of weakening affects to the distribution of stresses and displacements around the mine. To select the parameters of the lining support it is necessary to take into consideration weakenings and contacts in the ore massive and the distance for these zones.
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Date submitted2009-10-30
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Date accepted2009-12-09
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Date published2010-09-22
Investigation of regularities of rock inrush forming in productive faces of сoal mines
- Authors:
- Yu. M. Khalimendik
- A. V. Brui
- M. V. Chemakina
The aspect of maintenance of roof stability of active stopes in mines of the Western Donbass is considered in the article. The conclusion is drawn on the probability of coal falls formation during mining operations in disturbed areas. Principal causes of coal fall formation are considered on the bais of natural surveying observations. Connections between technological parameters of longwall and geometrical parameters of disturbance are established.
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Date submitted2008-10-29
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Date accepted2008-12-11
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Date published2009-12-11
Experience in providing the stability of tunnel face and roof during its drivage in proterozoic clays
- Authors:
- V. A. Maslak
Methodology for assessment of state of advance support of face with fiberglass anchors and the working¢s roof – with tube anchors, is given. The results of in-situ experimental observations for efforts in anchors, displacements of excavation and growth of load on the advance supports in its roof are shown.
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Date submitted1948-07-28
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Date accepted1948-09-12
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Date published1949-11-04
Frontal self-loading of coal in longwalls is the most important means of fulfilling the five-year plan of the coal industry in 4 years
- Authors:
- Ya. B. Kalnitskii
Implementation of mechanization of coal loading in the working face is one of the most important problems of the Soviet coal industry in the 4th Stalin Five-Year Plan. In the "Law on the Five-Year Plan for the Restoration and Development of the National Economy of the USSR for 1946-1950" it is written: "In order to implement the established program for the growth of coal production, construction and increase in labor productivity - mechanize labor-intensive processes in the coal industry in every possible way, in particular, ensure the widespread implementation of work on the mechanization of coal loading and rock loading." There are three main possible ways of mechanization of coal loading in the working face: Partial mechanization of loading, i.e. loading onto the conveyor not all of the extracted coal, but some of it. Full mechanization of loading, performed by specialized loading machines. Complex mechanization of coal loading and extraction; the executive machine in this case is a mining combine or cutting-cutting-bulking machine. The second and third methods require the creation of highly sophisticated designs of bulk machines and mining combines.