Vol 148 No 2
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Date submitted2000-07-02
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Date accepted2000-08-04
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Date published2001-02-01
Problems of environmental safety monitoring at blasting sites
- Authors:
- N. N. Aleinikov
- N. N. Vershinin
- K. K. Shvedov
Environmental impact of explosion on the environment is associated with a significant release of harmful gases and dust into the atmosphere, their pollution and products of incomplete decomposition of explosives of the ground and groundwater. In places of mass blasting works during mining of minerals there is chemical pollution of ground and surface water, deterioration of the biological landscape. In large-scale explosions may fall solid precipitation and acid rain at large distances from the explosion site.
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Date submitted2000-07-21
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Date accepted2000-08-24
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Date published2001-02-01
The degree of impact of crushing quality on the energy intensity of technological processes in the production of crushed stone
- Authors:
- A. I. Arsentev
- O. N. Talamanova
The initial raw material for the production of crushed rock is blasted rock, which is subject to processing at crushing and screening plants. The granulometric composition of the rock mass depends on a number of factors, in particular: the method of drilling and blasting, physical and mechanical properties of minerals, etc.
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Date submitted2000-07-12
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Date accepted2000-08-17
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Date published2001-02-01
Expert method of reducing uncertainty in seismic safety calculations of blasting operations
- Authors:
- V. A. Belin
- D. K. Potresov
- N. I. Bukhanova
Analysis of the current state of blasting operations has shown that further growth in the intensity and scale of blasting operations is constrained by the harmful effect of seismic waves caused by blasts on the environment. In order to avoid such action of seismic waves, as well as to increase the efficiency of blasting and to ensure seismic safety of blasting works it is necessary: to determine more accurately the parameters, intensity and permissible levels of the impact of seismic blasting and take into account the influence of various factors of seismic blasting.
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Date submitted2000-07-24
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Date accepted2000-08-13
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Date published2001-02-01
Expert system of seismic safety of blasting operations
- Authors:
- V. A. Belin
- D. K. Potresov
- N. I. Bukhanova
Expert method of reducing uncertainty in calculating seismic safety of blasting operationsAnalysis of the current state of blasting operations has shown that further increase in the intensity and scale of blasting operations is constrained by harmful effects on the environment of seismic waves caused by blasts. To avoid such action of seismic waves, as well as to increase the efficiency of blasting and to ensure seismic safety of blasting operations it is necessary to: more accurately determine parameters, intensity and permissible levels of the impact of seismic blasting and take into account the influence of various factors of seismic blasting.
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Date submitted2000-07-22
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Date accepted2000-08-14
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Date published2001-02-01
Principle of database construction for the expert system of seismic safety of blasting operations
- Authors:
- V. A. Belin
- D. K. Potresov
- A. D. Lvov
One of the components of the seismic safety expert system (ESSS) structure is the database (DB), which is part of the knowledge base - the core of the ESSS [2]. The database stores factual information about the problem to be solved and data that are relevant to the subject area under consideration.
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Date submitted2000-07-10
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Date accepted2000-08-30
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Date published2001-02-01
Influence of explosion energy on the quality of rough diamonds
- Authors:
- A. T. Vedin
- V. Ya. Konovalenko
Technogenic damage (TD) of diamond crystals is currently estimated by mass indicators: relative change in mass separately and in the sieve aggregate (degree of disturbance and mass loss in the class), the number of fragments in the class, etc. This system of indicators (10 grades of sieve size and two major indicators per grade) does not permit unequivocal estimation of quality changes in rough diamonds as a whole and description of many physical and mineralogical changes (cracks, microdefects). More expedient may be the estimation of technogenic changes in the value of crystals. Its price parameters can serve as a scale of importance, and crystal value can be considered as an integrated quality indicator. Interrelation between TD, cost of crystals and extraction parameters and dressing technology in general is caused by natural uncertainty of change of sieve and quality composition of diamond crystals, high statistical variation with low frequency of appearance of some indicators (for example the price of very large crystals) that requires analysis of large statistical samples and hasn't been evaluated so far. In addition, the influence on the damageability of crystals in the processes of mechanical crushing and grinding the degree of dissolution of pieces of ore during the explosion has not been determined. Indirect confirmation of possible ambiguous influence of explosion energy on damageability of crystals are results of experiments [5], in which growth of energy costs at BWR on 25 % led to their reduction on ore preparation as a whole, taking into account crushing and grinding processes at the plant, on 10 %.
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Date submitted2000-07-14
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Date accepted2000-08-19
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Date published2001-02-01
Quality of rock blasting as the basis of profitability of a crushed stone plant
- Authors:
- Yu. I. Vinogradov
- A. G. Zatonskikh
Market economy not only establishes new economic relations between different enterprises, but also forces a different assessment and, consequently, the solution of certain technological problems. In particular, at the enterprises producing fractional crushed stone, the parameters of the main technological processes are calculated according to the factor of minimum cost. At such approach to designing overestimates output of unprofitable fractions, price and demand for which is much less than price and demand for deficit fractions. Therefore, as the basic criterion for designing technological parameters, it is necessary to accept the maximum profit from realization of production.
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Date submitted2000-07-10
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Date accepted2000-08-02
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Date published2001-02-01
Development of technical means to improve the safety of blasting operations in mines, hazardous in gas and dust
- Authors:
- Yu. V. Gorlov
Conducting blasting operations in coal mines, hazardous gas or dust, is fraught with the danger of initiating an ignition and explosion of methane-air mixture and coal dust. This is due to the fact that the methane sorbed by coal from the rock mass destroyed by the explosion is released into the worked-out space. The mixture of methane and air formed in this case comes into contact with gaseous and solid high-temperature products of the explosion. An even greater danger is posed by the burnout of undetonated explosive remnants. Deflagration of explosive remnants after blasting off for a long time is a source of ignition with the intense growth of methane concentration in the mine working. Exactly the latter was the main reason of big accidents in mines related to methane ignition, as the direct effect of blasting works was restrained by the use of explosives and fulfillment of measures in accordance with safety regulations. Of all registered cases of methane and coal dust explosions in workings in the mines as a whole on the share of blasting works accounts for 46.2%, including preparatory mine workings - 74.1%.
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Date submitted2000-07-06
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Date accepted2000-08-14
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Date published2001-02-01
Calculation of the main parameters of drilling and blasting operations in the explosion of selective detonating explosive charges
In our country, for the last 10-15 years, a new type of explosives and charges made of them with the necessary complex of energy and gas release have been developed. At explosion of these charges, their throwing properties are implemented in full measure, i.e., brisant influence on a rock is practically excluded. The pilot and industrial production of these charges is mastered and they are successfully used in a number of block quarries in the Leningrad, Murmansk and Irkutsk Regions and in the Republic of Karelia and are permitted by the Russian State Mine Technical Supervision Service for permanent use in the mining industry. The explosion of these charges provides an explosive transformation in the form of explosive combustion in the explosive chamber (borehole, well), creates a pressure that is significantly lower the compressive strength of the rock and 1.2-1.5 times the breaking strength of the rock, increasing the exposure time on the walls of the explosive chamber gaseous products of explosion (PE). Employees of the rock destruction department of the St. Petersburg Mining Institute together with employees of the SKTB "Technolog" and NPO "Kristall" have developed special charge designs: elastic tubular charges (ZET "Granilen") and hose charges (ZShA).
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Date submitted2000-07-01
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Date accepted2000-08-03
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Date published2001-02-01
Perspectives for intensification of operation of mining pits on the basis of environmental safety requirements
- Authors:
- A. S. Derzhavets
- V. I. Romanov
- O. I. Khokhlov
Ensuring reliable and rhythmic operation of mineral quarries is currently hampered by environmental safety requirements. The main sources of air pollution in quarries are internal combustion engines of loading and unloading equipment, rock explosions and accidents. Explosions result in emissions of solid-phase contaminants in the form of dust and gaseous toxic chemical compounds, internal combustion engines only emit gaseous.
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Date submitted2000-07-14
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Date accepted2000-08-03
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Date published2001-02-01
Calculation of rational parameters of fracture of frozen soils during the construction of excavations of given dimensions
- Authors:
- I. I. Drozd
The volume of civil, industrial, transport and military construction work in seasonally frozen and permafrost soils is significant and increases every year, including with explosive methods of loosening these soils.
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Date submitted2000-07-08
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Date accepted2000-08-06
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Date published2001-02-01
Assessment of the level of acoustic effect from an open pit explosion
- Authors:
- M. G. Egorov
- V. A. Artemov
- V. A. Mikhailov
The intensity of the airborne shock wave (AHW) impact on the structures located in the area of blasting operations, when designing blasting operations, is estimated by the value of excess pressure at the front of the wave. As an admissible level of exposure is usually taken the overpressure at the front of the shockwave 700-800 Pa, at which the destruction of glazing of buildings does not occur. However, the dynamic waves formed during the explosion with a pressure drop of about 1 kPa with low (16-60 Hz) and infra-low frequencies can cause dizziness and headaches in the population.
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Date submitted2000-07-28
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Date accepted2000-08-21
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Date published2001-02-01
Combined technology for ore-bed breaking with concentrated and beam charges
At Siberian mines tests were conducted and commercial development of combined technology of rock mass stripping with the use of vertical concentrated charges (VKZ) and beam borehole charges began.
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Date submitted2000-07-25
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Date accepted2000-08-24
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Date published2001-02-01
Development of rational constructions of vertical concentrated explosive charges for mass destruction of ore
- Authors:
- A. A. Eremenko
- I. V. Mashukov
- S. F. Fefelov
In the practice of blasting in the mining industry during mining of minerals by underground mining for crushing the rock mass, borehole charges of explosives, as well as borehole and stone (mine) charges located in the chambers, tunnels and mine wells are used. The largest volume of rock mass removal is currently carried out by borehole explosive charges. Mines in Gornaya Shoria, Khakassia and the Urals use the technology of stripping by bundles of parallel-conjugated borehole charges.
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Date submitted2000-07-11
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Date accepted2000-08-29
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Date published2001-02-01
Development of an effective method of dust suppression for mass explosions in mining pits
- Authors:
- G. G. Karkashadze
- I. V. Novikov
Mass explosions in ore pits are powerful sources of environmental pollution. In the process of explosion, a dust cloud is formed, containing a significant amount of solid products of destruction of rocks and toxic gases, which are transported over significant distances, polluting the surrounding area of the quarry. The environmental damage caused to the surrounding area is partially compensated by penalties to mining enterprises from environmental authorities, but it does not eliminate the problem of environmental pollution.
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Date submitted2000-07-08
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Date accepted2000-08-11
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Date published2001-02-01
Development of water-towering way of breaking wells in drilling and blasting operations at mining open pits
- Authors:
- G. G. Karkashadze
- N. O. Taran
The water cut of working benches in ore pits does not allow the wide use of the simplest types of explosives and causes the necessity of using water-resistant explosives, which significantly increases the cost of blasting operations. In cases when granulotols are used in watered boreholes, there is a very significant environmental load due to increased toxicity of explosion products and high dust-forming ability.
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Date submitted2000-07-09
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Date accepted2000-08-28
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Date published2001-02-01
Priority areas for the development of the coal, ore and construction oil mining industry by open pit mining to improve blasting methods
- Authors:
- B. N. Kutuzov
The limited financial capabilities of the mining machine-building industry require identifying the most important priority areas, the solution of which will make it possible to achieve technical progress in improving the productivity of drilling equipment and machinery, creating new explosives and technologies for their use, producing new means of initiation, significantly increasing the effectiveness of blasting preparation of rock for excavation and processing.
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Date submitted2000-07-19
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Date accepted2000-08-18
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Date published2001-02-01
Theoretical basis of an express method of explosive fracture assessment based on seismic signal parameters
- Authors:
- S. V. Lukichev
At different times and by different authors, attempts have been made to relate the amplitude-frequency characteristics of the seismic signal to charge parameters, conditions of its detonation, and the size of the fracture produced by the explosion. To such attempts it is possible to refer results of measurement of parameters of stress waves at explosion in conditions of all-round compression, experimental and theoretical researches of speed of growth of cracks from explosion of a single charge in rocks. The dependence linking the frequency of medium oscillation with the Poisson's coefficient, longitudinal wave velocity and the maximum radius of the fracture zone is proposed.
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Date submitted2000-07-08
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Date accepted2000-08-03
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Date published2001-02-01
Directions for the development of comprehensive mechanization of blasting operations in the mines of Mountain Shoriya and Khakassia
Mechanization of blasting operations at underground mines in Gornaya Shoria and Khakassia began in the 1970s using granulated explosives and pneumatic charging equipment. Mines tested charging machines UZS-1500, UZS-6000, UZDM-1, 3MB, ZMBS-1 and ZMBS-2 developed by NIPIGormash company.
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Date submitted2000-07-12
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Date accepted2000-08-23
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Date published2001-02-01
Model of the granulometric composition of the fractured mined rock at the edge
- Authors:
- M. G. Menzhulin
- G. P. Paramonov
- S. V. Khokhlov
The formation of the structure of the chipping zone can be investigated using the method proposed by B.V. Zamyshlyaev to determine the structure of the cavitation layer during explosion of explosives in water near the free surface. The method is based on the use of the laws of disintegration of an arbitrary discontinuity during the interaction of a stress wave with a free surface. As a result of the interaction, a shock wave will propagate in the air, and a rarefaction wave will propagate along the condensed medium from the interface toward the explosion chamber. The maximum tensile stress in the rarefaction wave is determined by the method of mirroring the explosion source with the introduction of an imaginary charge.
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Date submitted2000-07-04
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Date accepted2000-08-15
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Date published2001-02-01
Improvement of safety of blasting operations at pyrite mines
- Authors:
- G. P. Paramonov
Conducting excavations and clearing works on colliery ores in a number of cases is accompanied by sulfide dust explosions, which release a large amount of sulfur dioxide gas, significantly exceeding the allowable by standards, which leads to increased airing time and long downtime of faces, and sometimes to severe poisoning of people. Release of sulfur dioxide gas occurs in conventional faces, not dangerous in terms of sulfide dust explosion, due to its low ignition temperature (about 400-450°С). To improve the safety of blasting operations it is necessary to study the kinetics of ignition and explosion of sulfide dust.
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Date submitted2000-07-17
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Date accepted2000-08-07
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Date published2001-02-01
Intensity based on seismic scale, vibration velocity and distance reduction in blasting
Back in the early 1940s, M.A. Sadovsky established the fact of correlation of the degree of damage to buildings and structures during explosions with the value of the maximum velocity of ground oscillations on the day surface (at the base of structures). The value of this velocity in the case of instant explosions of concentrated (and equivalent to them spatially dispersed and short-delayed) charges is modeled by a two-parameter argument - the equivalent reduced distance, which displays the energy principle of similarity of phenomena in explosions.
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Date submitted2000-07-09
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Date accepted2000-08-17
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Date published2001-02-01
Development of devices in the modernized technology of drilling and blasting operations for joint mining of ore and ornamental granite in the contours of a common pit
- Authors:
- S. K. Rubtsov
Improvement of efficiency of mining production is directly connected with increase of a degree of use of extracted from a subsoil both the basic and jointly developed or by-product minerals. Application of mass explosions at open-cast mining causes the necessity to protect the sites of jointly developed or nearby deposits from harmful seismic-explosive effects.
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Date submitted2000-07-26
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Date accepted2000-08-05
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Date published2001-02-01
Improvement of blasting operations at quarries in the south of Kuzbass
- Authors:
- I. V. Timoshin
- A. V. Zykov
In May 1994 at the joint meeting of directors and chief engineers of coal mines of Southern Kuzbass with participation of specialists of OAO Progress (Kemerovo) and scientists of VostNII Institute it was decided to create in Mezhdurechensk division to produce simple explosives and in the future to improve technology of drilling and blasting operations.
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Date submitted2000-07-13
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Date accepted2000-08-01
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Date published2001-02-01
Technology of explosive demolition of an industrial high-rise building with a metal bearing frame
At many enterprises, depreciation and amortization of buildings and structures significantly exceeds the standard terms. After the commissioning of new facilities, the old ones are closed, their repair and maintenance are stopped. Buildings fall into an emergency condition with spontaneous collapse of walls and elements of building structures with the possible accidental presence of people in the danger zone. Responsibility for the occurrence and consequences of a hazardous situation is borne by the company in charge of the facility. In order to eliminate the hazardous situation, it is necessary to carry out measures to eliminate the emergency facilities.
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Date submitted2000-07-18
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Date accepted2000-08-22
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Date published2001-02-01
Justification of rational arrangement of the grid of rupture holes formed during explosive fracture to improve the quality of the pelletizing process based on the superposition of dynamic stress in two-dimensional space
- Authors:
- A. G. Fedorov
Currently, a rectangular (square) grid of boreholes is used in iron ore pits, which in technical terms seems most appropriate due to the simplicity of creating, maintaining and accounting for blasting wells and short-delayed blasting (SDF) schemes. The drilling of blocks with a rectangular grid of wells also provides the possibility of a greater choice of groups and schemes of BHA. However, a comprehensive study of the action of blasting in rocks has shown that with a rectangular grid of wells the efficiency of explosive energy is far from optimal, as evidenced by a fairly large yield of oversize (5-10%) and the huge unevenness of the blast block, requiring additional costs of effort, money and time.
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Date submitted2000-07-18
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Date accepted2000-08-17
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Date published2001-02-01
Investigation of fracture processes of composites with hybrid spatially reinforced weighting material
- Authors:
- G. E. Freger
- V. P. Tatsienko
- V. M. Buchatskii
The strength characteristics of composites based on spirally reinforced fillers used in the mining industry have higher strength values under almost all types of loading than unidirectional plastics. While the increase in strength of a material with spirally reinforced filler in the transversal and shear directions is theoretically justified, the characteristics in the main reinforcement direction should have lower values due to the reduction of the main reinforcement content in the material. At the same time, the influence of the wrapping layer on the strength characteristics of reinforced plastic begins to affect already at the stage of production of spirally reinforced elements. The presence of the winding layer not only improves the manufacturability of reinforcement processing, but also contributes to a fuller use of its strength in the material. Positive effect is achieved due to straightening of elementary fibers, sealing and compression of reinforcement harness, which contributes to their simultaneous inclusion under loading.
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Date submitted2000-07-04
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Date accepted2000-08-18
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Date published2001-02-01
Mixed charge devices for emulsion explosives
One of the achievements in the field of development of industrial explosives for surface mining works is creation of emulsion explosives on the basis of reverse emulsions of highly concentrated solutions of oxidizers (ammonium, sodium or calcium nitrate) and oil products (fuel oil, industrial oil, diesel fuel) in the presence of emulsifier. Emulsion explosives are effective substitutes of regular industrial explosives due to availability of raw materials (ammonium nitrate and oil products), safety and environmental friendliness in manufacturing and application, high water resistance and explosion efficiency, lower cost price.
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Date submitted2000-07-29
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Date accepted2000-08-09
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Date published2001-02-01
Industrial explosives on bases of reconstituted (conversion) explosives
The development of industrial explosives (EE) on the basis of conversion explosives (CF) was carried out taking into account a number of assumptions. On the basis of this approach and analysis of the formulation and technological features, all the recoverable munitions were divided into four main groups. This classification of explosive materials made it possible to propose for each group a rational set of industrial explosive materials, to provide them with appropriate regulatory documentation and to implement the method of its production in factories.
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Date submitted2000-07-10
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Date accepted2000-08-21
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Date published2001-02-01
Damping plate parts test of the moving cover
- Authors:
- E. B. Shevkun
- N. A. Leonenko
At the 1st International Scientific Conference on Physical Problems of Rock Fracture we presented the results of scientific and technological substantiation of progressive technology of open-pit mining based on a fundamentally new approach to drilling and blasting operations: rock fracturing is carried out by layer-by-layer (from top to bottom) blasting of horizontal borehole charges of reduced diameter (with preliminary slotting along the contour of the blasted volume) under a mobile shelter in the form of a shield with damping elements.
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Date submitted2000-07-25
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Date accepted2000-08-16
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Date published2001-02-01
Environmental issues in building materials extraction
- Authors:
- Yu. V. Shuvalov
- A. L. Gubenko
- A. P. Bulbashev
Atmospheric emissions of harmful substances during the development of mineral deposits by open-cut mining mainly include mechanical (dust) and chemical impurities. Among the latter, depending on the technology of works, carbon oxides, nitrogen, sulfur dioxide, etc. prevail.
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Date submitted2000-07-03
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Date accepted2000-08-15
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Date published2001-02-01
Determination of strength and abrasiveness of rocks by the spectrum of acoustic noise during drilling and cutting
- Authors:
- A. G. Arkhipov
For instrumental determination of rock strength, drillability category and abrasiveness in laboratory conditions several methods have been proposed. For determination of rock strength and drillability the method of L.A. Schreiner was widely used, and in geological exploration drilling the method of CNIGRI developed by N.I. Lyubimov was the most widespread. Abrasiveness of rocks is determined mainly by the degree of wear of reference material (rods, rings, etc.) during interaction (friction, drilling, cutting) with the rock sample. The most widespread in drilling were methods of evaluation of abrasiveness proposed by N.I. Lyubimov and L.I. Baron and A.V. Kuznetsov. Application of these methods, undoubtedly, played a positive role in the study and typification of the mechanical properties of rocks. However, as it follows from the published materials, determining the category of rocks by their drillability or choosing the design parameters of diamond tools on the basis of the established indicators is very difficult, because they usually do not correlate with each other and with the performance of diamond drill bits. This result could have been predicted, since the tests used the simplest types of loading.
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Date submitted2000-07-29
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Date accepted2000-08-28
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Date published2001-02-01
Thermal processes of rock fracture during course mechanical core drilling
- Authors:
- G. S. Brodov
Exploration core drilling is characterized by a variety of mining and geological conditions. This requires constant improvement of traditional, development of new advanced technologies of well drilling and design of drilling rock destruction tools.
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Date submitted2000-07-14
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Date accepted2000-08-03
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Date published2001-02-01
Experimental studies on ice cutting
- Authors:
- N. I. Vasilev
- V. M. Zubkov
In order to drill "dry" wells in snow-firn and ice strata, the SPbSMI (TU) Department of Drilling Technology and Technology is developing a technology of mechanical drilling with bottom-hole air circulation to remove cuttings. The electromechanical drilling tool for drilling with bottom-hole air blowout is similar to the previously developed KEMS-112* drilling tool for drilling deep wells filled with filling fluid.
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Date submitted2000-07-13
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Date accepted2000-08-22
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Date published2001-02-01
Experimental simulation of the penetration of chemically active aerosol into destructible material
- Authors:
- S. D. Viktorov
- N. G. Demchenko
- A. P. Kuznetsov
At the previous conference, the authors made a presentation about a very effective way of destroying materials (including rocks) with the help of low-pressure chemically active jet (CJA) impact on them. Further study of the phenomenon led to the formulation of a mathematical problem about the penetration of the CAB in the destructible material. The formulation of this problem was accompanied by consideration of the spherically symmetric thermal conductivity equation with a boundary condition of the first kind and with a threshold criterion for thermal destruction.
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Date submitted2000-07-24
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Date accepted2000-08-09
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Date published2001-02-01
Energy balance of rock fracture and contact problems of exploratory drilling
- Authors:
- L. K. Gorshkov
- B. G. Tarasov
- N. I. Nikolaev
The study of energy balance in rock fracture is one of the directions of the scientific school of deformable solid mechanics developed for several decades at the Department of Structural Mechanics of the St. Petersburg (Leningrad) Mining Institute. The formation of this school is connected with the works of L.S. Burshtein, N.S. Bulychev, N.N. Kaidalov, A.N. Stavrogin and others. The practical results of this school are known at many sites of underground construction, in the mining industry, in exploratory drilling. Within the framework of this article, modern ideas about the mechanism of transformation of potential energy of elastic compression into dynamic types of energy during brittle fracture are briefly described, the balance of energy of this process is given, as well as examples of its use in solving a number of contact problems of exploratory drilling, least covered in the technical literature.
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Date submitted2000-07-22
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Date accepted2000-08-09
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Date published2001-02-01
Fracture energy capacity as a criterion for stability of building clay backfill
- Authors:
- L. K. Gorshkov
- S. V. Naumov
The stability of the clay outcrop when driving transport or sewage tunnels determines the efficiency and safety of mining operations, as the time of the steady state of the clay outcrop depends on the regulated lag of the permanent excavation support, the mechanization method of excavation works, the time of rock mass removal, etc. In addition, clayey strata in recent years are widely used as storage facilities for various wastes (e.g., radioactive), so the steady state time of the outcrop plays an important role here, too.
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Date submitted2000-07-04
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Date accepted2000-08-16
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Date published2001-02-01
Electro-pulse method of rock fracturing and drilling wells
- Authors:
- D. V. Zhgun
- V. F. Vazhov
- M. Yu. Zhurkov
Traditional methods of destroying and processing rocks and artificial materials, based on mechanical destruction, have practically approached the limit of their technical capabilities. The inevitable disadvantage of the most common mechanical methods of fracture, as a consequence of using intense pressure on the rock, are high specific energy costs, low durability and high wear of the fracturing tool.
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Date submitted2000-07-17
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Date accepted2000-08-22
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Date published2001-02-01
Scientific and practical issues of core preservation technology developed by VITR
- Authors:
- V. A. Kaulin
- P. P. Ponomarev
The main objective of core drilling is to obtain reliable geological information about the field under exploration. Its most important component is the core sample, since a natural rock sample raised from various, often very significant, depths allows to assess a number of characteristics of a particular geological section, in particular, such as its structure and mineralogical composition, petrographic features, etc.
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Date submitted2000-07-11
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Date accepted2000-08-04
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Date published2001-02-01
Fundamentals of Aseptic Baring of Subglacial Lake Vostok
- Authors:
- B. B. Kudryashov
- A. N. Dmitriev
- N. I. Vasilev
Ecologically safe penetration into the subglacial Lake Vostok discovered in the depth of 3,700 m in East Antarctica (more than 10,000 km2 , hypothetically freshwater and containing relict life forms) requires development of new methods, technologies and technical means of drilling.
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Date submitted2000-07-02
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Date accepted2000-08-14
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Date published2001-02-01
Development of sealing and lubrication systems for bearings of high-speed roller bits
Unprecedentedly difficult operating conditions of roller cone bit bearings, leading in many cases to their failure at the initial stage of operation, require not only a detailed study of operation and wear of individual elements of the bearings, but also further search for ways to improve them.
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Date submitted2000-07-09
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Date accepted2000-08-26
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Date published2001-02-01
Specifics of drilling flowing wells in intervals of unstable formations
One of the most common types of geological complications arising when drilling wells through permafrost rocks is the violation of wellbore integrity due to changes in the natural stress state of the surrounding massif. Securing the wellbore walls with casing requires switching to a smaller drilling diameter, and the use of grouting materials for grouting fractured rocks is ineffective, since cracks are usually filled with ice, preventing the penetration of grouting material into them.
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Date submitted2000-07-09
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Date accepted2000-08-28
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Date published2001-02-01
Issues of fracture research in drilling explosive boreholes
- Authors:
- R. I. Sukhov
- Yu. M. Lebedkin
- A. V. Tymchur
According to the principles of rock destruction, mechanical drilling of wells can be carried out in several ways, differing in their physical nature. For medium- and high-strength rock, roller cone bits with milled cutting structure or reinforced with high-strength tungsten carbide pins are used. The roller cone method of drilling implements the principle of bottom-hole destruction due to static impingement of the cutting structure, the rock is destroyed mainly by a piercing, partially blocked chipping. From the energy point of view, such impact on the bottom hole is not optimal.
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Date submitted2000-07-18
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Date accepted2000-08-01
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Date published2001-02-01
Thermal regime of ice breaking in rotary drilling
- Authors:
- P. G. Talalai
In recent years, mechanical rotary ice drilling has become the main type of construction of deep boreholes in the ice of the Antarctic and Greenland ice sheets. Work continues in these regions to study the paleoclimate of the Earth, the dynamics and composition of ice sheets, the influence of anthropogenic pollution on climate change and other natural scientific problems. As a result of various national and international projects, deep boreholes were drilled in Antarctica at Dome F (2503 m, 1996), Vostok Station (3623 m, 1998), Dome C (1458 m, 2001) and in Greenland at NGRIP (1371 m, 1997; 2931 m, 2000).
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Date submitted2000-07-01
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Date accepted2000-08-09
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Date published2001-02-01
Issues in mechanical ice drilling
- Authors:
- I. G. Shelkovnikov
Drilling of the ice cover in different areas of the globe, and, above all, in Antarctica and Greenland, attracts the scientific community mainly by the opportunity to study the history of the Earth's development using mineral and biological inclusions. Large ice columns, accumulated over many millennia, preserve inclusions, which can be used to judge, in particular, about possible cataclysms on the planet in different periods of its life, microbiological and other changes in its development. Such inclusions can be mineral dust particles, microorganisms in their various forms, plant spores, contained in drilling ice cores, lifted from various depths of wells. Such boreholes are penetrated either by melting ice with an annular heating tool, inside which a column of ice core remains, or by mechanical rotary method, in which ice is broken by a cutting downhole tool in the form of a bladed drill bit with a central hole for core penetration. Let us dwell in more detail on the mechanism of ice breaking during drilling by this method.
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Date submitted2000-07-12
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Date accepted2000-08-12
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Date published2001-02-01
Theoretical fundamentals of ice drilling using a relief slot
- Authors:
- A. M. Shkurko
The stability of the walls of wells drilled in a rock mass depends on the stressed state of rocks, their physical, mechanical and rheological characteristics, and the borehole drilling technology. Loss of wellbore stability causes a number of serious complications and accidents in wells. In solving the problem of stability of a wellbore drilled in an ice massif, an attempt has been made to take into account all the main factors influencing the process of wellbore deformation and to obtain a mathematical description of the latter, convenient for practical use in engineering calculations.