"Explosion technology"— scientific and technical journal

Experimental check of the probabilistic model of short-delay initiation of downhole charges system

Keywords:mass explosions, electronic means of initiation, seismic impact, seismogram, displacement velocity

The article formulates the basic principles of the methodology for calculating the actual time of initiation of downhole charges system at short-delay blasting, based on the normal law of distribution of downhole and surface detonators firing time. As an example, there has been performed a calculation of the number of charges falling into 20 ms simultaneity groups with overall explosive weight in these groups, while using pyrotechnic downhole detonators ISKRA-S and hybrid electronic detonators ISKRA-T. The calculation results have been compared with seismograms of displacement velocities, recorded during blasting of the corresponding blocks in certain mining conditions. It is shown that the calculated histograms of mass distribution into simultaneity groups are consistent with the position of the displacement velocities peaks in seismograms. Application of hybrid electronic detonators ISKRA-T allows to decrease the number of charges, initiated within an interval below 20 ms.

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2. Grib G.V. Dependence of seismic impact of blast in a rock mass on the technological conditions for blast operations / G.V. Grib, A.Yu. et al. // Bulletin of the Samara Scientific Center of the Russian Academy of Sciences, Volume 14, No. 1 (8), 2012
3. Sysoev A.A. Analysis of systems for initiating downhole charges in open pits// Izvestiya Vysshikh Uchebnykh Zavedenii. Mining Journal. 2016. No. 4. P. 60-67.
4. Kondratyev S.A. Modern means of initiation of JSC "NMZ "Iskra". S.A. Kondratyev, S.A. Pozdnyakov, A.S. Ivanov, K.A. Vandakurov // Blasting. –2019. – No. 123/80. – P. 136-144.
5. Mashukov I.V. Calculation of safe distances for seismic impact of mass explosions onto buildings and constructions with consideration of downhole charge blast design. /I.V. Mashukov, V.P. Domanov, A.G. Serg, D.A. Yegorov // Bulletin of Scientific center for blast operations safety in coal mining. 2013. No. 1.2. pp. 6-23.

The effect of construction charges on the particle size distribution of rock mass

Keywords:opencast mine, charge design, borehole stemming, locking device, ganulometric composition, oversize output, mined rock collapse, reflection waves, delay of the stemming departure

The article describes the characteristics of borehole breaking at mines of building materials. The problem of reaming of the lower part of the ledge in the first row of wells is considered. To solve the problem of mined rock reaming along the toe line of resistance, the article proposes a change in the parameters of the borehole charge, namely the design of the stemming unit. The paper describes the construction of the proposed design of the stemming unit and its effect. Based on the results of theoretical studies, polygon tests of the action of a locking gas-dynamic device were carried out. The tests were carried out at the mines of building materials of Leningrad region. The obtained data were processed and the results of the distribution of the particle size distribution of the mined rock collapse were constructed. The article shows the logarithmic distribution, according to the particle size distribution, based on the data obtained from the explosion in the experimental blocks. Based on all the results obtained, conclusions were drawn about the positive effect of the unit, as well as company received the recommendations of using the stemming.

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4. Sher E.N., Aleksandrova N.I. Investigation of the effect of borehole charge structures on the size of the fracture zone and its development time in rocks during an explosion // Novosibirsk, Siberian Branch of the Russian Academy of Sciences the Journal Physical and technical problems of mining, No. 1, 2007. P. 76 – 85.
5. Kovalevskiy V.N., Rumyantsev A.E., DambaevZh.G. Quality assessment of facing stone blocks during their explosive separation from the massif by charges of various designs // Development of mineral resources of the north: problems and solutions: Vorkuta Mining Institute (branch) of the Federal State Budgetary Institution of Higher Education «National Mineral Resources University «Gornyy». – Vokruta, 2013. P. 80-82
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8. Baron S.I., Sirotyuk G.N. Testing of the applicability of the Rozin-Rammler equation for calculating the diameter of the middle piece during explosive breaking of rocks. // Collection «Explosive business», Nedra, 1967, No. 62/19.
9. Kazakov N.N., Viktorov S.D. Determination of the parameters of the collapse of the mined rock repelled by the explosion at the mines. // Physical problems of rock destruction. Novosibirsk, Nedra, 2003. – P. 137-140.

Explosive crushing of mineral salts in the borehole method of their production

Keywords:mineral salts, explosive, borehole charge, charge parameters, fine crushing, adjustable crushing zone

The analysis of influence of various factors on the sizes of zones of regulated crushing and crushing in relation to explosive destruction of a productive layer at extraction of mineral salts by a borehole method is carried out. The dependences of the relative radius of the controlled crushing zone on the initial pressure of the detonation products of the explosive, on the strength of mineral salts are given. These data can be used in the selection of types of industrial explosives depending on the physical and mechanical properties of mineral salts.

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11. Dugartsyrenov A.V. The Physical nature and the mechanism of destruction of rocks during camouflet explosion. The explosive case. Issue #106/63. – Moscow: CJSC «MVK on explosive case at AGN», 2011. – pp. 112-126.
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13. Belin V.A., Dugartsyrenov A.V., Levkin Yu.M., Kamolov Sh. A. Experimental and industrial tests to improve the efficiency of explosive loosening of complex structural arrays with strong inclusions of the jaroy – Sardar Deposit using a new structure of borehole charges of explosives. – ANALIT. – 2009. – No. 12.OV. – Surveying support of blasting operations. – Pp. 26-34.
14. Dugartsyrenov A.V., Kim S.I., Kamolov S. A. Features explosion-tion of the destruction complex patterns with layers of hard rocks // Mining Bulletin of Uzbekistan. – Navoi, 2014. – No. 2. – Pp. 72-76
15. Dugartsyrenov A.V., Kim S. I., Belchenko E.L., Nikolayev S.P. Requirements to the choice of BWR parameters for crushing complex-structured rock masses with combined and additional charges / / Explosive case. – 2015. – No. 113/70. Pp. 142-148.

Mass explosion parameter management

Keywords:reduction of negative factors, seismic effect, a set of organizational and technical solutions, design of borehole charges, optimal intervals of slowdowns, operating time of the blasting unit

The article describes a number of additional technical solutions that allow to adapt the rock blasting technology to the performance of modern mining equipment while reducing the negative impact from blasting. The article presents a modern approach to conducting mass explosions using domestic means of initiation and downhole charge formation technologies, allowing to reduce the seismic effect from the explosion to a minimum.

Full-scale tests of the device based on energy-saturated acid-generating material

Keywords:field tests, device, energy-saturated acid-generating material, acid treatment, oil reservoir, technology, solubility

In the work, full-scale tests of the device based on acid-generating energy-saturated material were carried out and showed its greater efficiency in comparison with the used analogues – technologies of standard acid treatments. In particular, the use of the device based on the acid composition allowed to increase the solubility of the rock by 470%, reduce the reaction time of the acid with the rock by 5.1 times, reduce the number of unreacted acid residues by 2.3 times compared to standard acid treatment. The introduction of this device in the oil fields will create a new method of acid treatments, in which there is no need to pump liquid acids from the surface, while the formation of acid reagents occurs in the bottom-hole zone of the well. This method is more effective and safe, does not require the use of significant amounts of acid reagents, expensive metal-intensive equipment, which significantly reduces the cost of the technology used.

1. Agliullin M.M., Abdullin V.M., Abdullin M.M. et al. Razrabotka i vnedreniye termobarokhimicheskogo metoda uvelicheniya produktivnosti neftegazovykh skvazhin (Development and implementation of thermobarochemical method of increasing the productivity of oil and gas wells). Vestnik Tyumenskogo neftegazovogo universiteta = Bulletin of Tyumen oil and gas University. 2004. No. 3. pp. 186-189.
2. Surguchev M.L. Vtorichnyye i tretichnyye metody uvelicheniya nefteotdachi plastov : uchebnoye posobiye (Secondary and tertiary methods of increasing oil recovery : textbook). – M.: Nedra, 1985. 308 p.
3. Kudinov V.I. Osnovy neftegazopromyslovogo dela : uchebnoye posobiye (Fundamentals of oil and gas industry : textbook). – Izhevsk: Publishing house IzhGNU. 2004. 720 p.
4. Petrov A.S., Mokeev A.A., Garifullin R.S. et al. Sgorayemyye kislotogeneriruyushchiye kompozitsii dlya povysheniya nefteotdachi plastov (Combustible acid-generating compositions for enhanced oil recovery). Vzryvnoye delo = Explosive case. 2018. No. 121/78. pp. 124-135.
5. Sadykov I.F., Marsov A.A., Mokeev A.A. Universalnyy khimicheskiy reagent dlya kislotnoy obrabotki prizaboynoy zony neftyanykh plastov iz karbonatnykh i terrigennykh porod (Universal chemical reagent for acid treatment of bottom-hole zone of oil formations from carbonate and terrigenous rocks). Vestnik Kazanskogo tekhnologicheskogo universiteta = Bulletin of Kazan technological University. 2013. Vol. 16. No. 13. pp. 190-192.
6. Mars A.A., Mokeev A.A., Alyshbaev E.A. Pat. 2588523 Russian Federation, IPC E21B 43/18, IPC E21B 43/24. Ustroystvo dlya obrabotki prizaboynoy zony skvazhiny (Device for processing bottom-hole zone of the well). Applicant and patentee OOO «Perfoterm». No. 2015117629/03. Declared. 08.05.15. Publ. 27.06.16. Byul. No. 18.

Explosion welding simulation using ANSYS AUTODYNE

Keywords:computer model, explosion welding, aluminum, steel, performance parameters, explosives, software

The result of this work was a developed and proven technique that allows you to create a computer model of the explosion welding process of two blanks from different materials and determine their pressure at the point of impact for 14 main stages. For work used the software ANSYS AUTODYN. As a result of researches it is established that the computer model in the ANSYS AUTODYN environment allows not only to visualize process of welding by explosion, but also to observe it at different moments of time that it is impossible to make at carrying out full-scale experiments. Since the level range of the collision parameters, which provides a strong connection, is wide enough, it is most accurately determined in the window with a contour view of the process model, from which you can set the numerical value of the pressure at the point of contact.

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2. Lysak. I., Kuzmin S.V. Svarka vzryvom (Welding explosion). Moscow: Mashinostroenie. 2005. 544 p.
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4. Kornev V.M., Yakovlev I.V. Model volnoobrazovaniya pri svarke vzryvom (Model of wave formation during explosion welding). Fizika goreniya i vzryva = Physics of combustion and explosion. 1984. T. 20. No. 2. pp. 87 – 90.
5. Greenberg B.A., Elkina O.A., Patselov A.M. et al. Problemy peremeshivaniya i rasplavleniya pri svarke vzryvom (alyuminiy – tantal) (Problems of mixing and melting in explosion welding (aluminum – tantalum). Avtomaticheskaya svarka = Automatic welding. 2012. No. 9. pp.15-22.
6. Mukhutdinov A.R., Vakhidova Z.R., Efimov M.G. Kompyuternoye modelirovaniye brizantnogo deystviya vzryva (Computer modeling of the explosive action of the explosion). Informatsionnyye tekhnologii = Information technologies. 2016. Vol. 22, No. 5. pp. 340-343.
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8. Mukhutdinov A.R., Efimov M.G. Osnovy primeneniya ANSYS Autodyn dlya resheniya zadach modelirovaniya bystroprotekayushchikh protsessov: uchebnoye posobiye (Basics of ANSYS Autodyn application for solving problems of modeling of fast-flowing processes: textbook). Kazan: Publishing house of KAZAN state technical University. 2016. 244 p.

The use of lagrange diagrams in precise initiation blasting. Part i: two interacting blastholes

Keywords:deceleration, blast holes, rock fragmentation, fracture mechanics

Using the concept of Lagrange diagrams this contribution details the calculation of the delay timebetweenblastholes in a row and rows of blastholes with respect to precise initiation timing within the new advancedblasting technology which is based on the use of electronic detonators.
After introducing the representations of stress waves and cracks, this contribution focuses on the role ofstress wave interaction in optimal fragmentation in surface blasting and bench blasting. Part I of the paperconsiders two interacting blast-holes, Part II will be devoted to three or more out of plane interactingblastholes, whereas Part III will treat the interaction with a free face such as encountered in bench blasting.
A few simplifying assumptions have been made in this paper with respect to the rock mass as well as themechanical treatment. The essential assumptions include that the rock mass is treated as a continuum withfinite tensile and compressive strength and the effects of structural geology are not taken into account. Inaddition, the analysis in Part I is simplified by two `educational' assumption, that all waves are plane (i.e.,one-dimensional) waves and three-dimensional effects of finite size blastholes and charges are not taken into account.
This contribution will also show that knowledge in wave propagation and fracture mechanics is essentialfor the successful application of the new blasting technique in industry. In particular, the delay time, thewave speeds in the rock mass, the shape of the wave pulse and the acoustic impedance mismatch (notconsidered in this paper) have become decisive parameters in advanced blasting.
Utilizing the wave speed and wave shapes of detonations, large scale tests in various countries (Australia,Chile, etc.) have shown that optimal delay timing requires shorter delay times in conjunction with allowingfor a wider drilling pattern and the use of a grossly reduced amount of explosives, i.e., a lower powderfactor. This seemingly contradictory arrangement is fully justified by using scientific principles in blasting, and converting blasting from an art to a scientific discipline.

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A geological classification of rock mass quality and blast ability for intermediate spaced formations

Keywords:Blast ability, discontinuities, geological classification, rock mass

Success in the excavation of geological formations is commonly known as being very important in asserting stability. Furthermore, when the subjected geological formation is rocky and the use of explosives is required, the demands of successful blasting are multiplied. The present paper proposes the Blast ability Quality System (BQS), for organizing the classification of geological formations, using the change of the Blast ability Index (BI) in relation to the rock mass quality. The BQS combines the blast ability and the quality of rock masses with intermediate spaced (0,1-1m). The Blast-ability Quality System (BQS) can be an easy and widely – used tool as it is a quick evaluator for blast ability and rock mass quality at one time. Taking into consideration the research calculations and the parameters of BQS, what has been at question in this paper is the effect of blast ability in a geological formation with intermediate spaced discontinuities.

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Estimation of near-field peak particle velocity: a mathematical model

Keywords:near-field PPV, rock damage, blasting

Peak particle velocity (PPV) is an important parameter in estimation of rock and structural damage. Ingeneral, ground vibration is measured using a seismograph at a distance from the blast face to keep the instrument safe. However, rock damage due to blasting occurs very close to the blast hole and thus, PPV at the damaged zone can not be measured directly. In the far-field observations charge is considered as point source because the distance of measurement is significantly longer than the charge column length. However, in near-field PPV estimation charge length can not be ignored. Thus, a mathematical model is developed for estimation of near-field PPV. In the proposed model, effect of an elemental charge in the charge column is calculated and then summed up for the whole charge column.
Thus, it is assumed that blast waves from all the elemental charges of charge column reached at the point of interest at same time. This can be helpful in assessing the extent of blast-induced rock damage.

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Evolution of blasting practices at the EKATI™ diamond mine

Keywords:Ekati mine, blasting monitoring, slit formation

A review of blast designs and improved blasting practices at the Ekati Diamond Mine is presented along with the results of three blast-monitoring experiments. Blast monitoring was undertaken to investigate blast damage mechanisms in the mine's well jointed rock mass. Rock mass damage caused by production, pre-shear and wall control blasts was measured. Ekati uses 270mm holes for production blasting, and 165mm holes loaded with a decoupled charge for pre-shearing. The production blasts are loaded with bulk emulsion / ANFO blends. The mine plan involves using 30m double benches. A 30m high pre-shear is drilled and blasted prior to the production blasting that İs done with sequential 15m benches. This paper summarizes the monitoring equipment and data gathered to datе.

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Near-field blast vibration models

Keywords:Holmberg-Persson field, dynamic finite element model, vibration damage

There is a persistent use of the Holmberg-Persson near-field vibration damage model despite the fact that ten years ago it was shown to be incorrect on the grounds of simple physics. In order to address this problem, the detailed recipe for a new, easily implemented model is presented. This new model, the Scaled Heelan model, is based on a standard Heelan (waveform) model altered to incorporate charge weight scaling. This Scaled Heelan model, thus, maintains some aspects of the original spirit of the Holmberg-Persson approach. A comparison of the Heelan models, a dynamic finite element model (DFEM) and a new full-field model is given, showing good agreement between the DFEM and fullfield solutions in all cases. However, the Heelan models show some discrepancies for certain frequencies of wave propagation, even at large distances from the source. Nevertheless, these Heelan models have value simply because they include influences such as the detonation velocity and the various wave types, and, furthermore, require significantly less computing time than that required for either the DFEM or full-field solutions.

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Experimental and numerical study of the dead-pressing of a chemically gassed emulsion explosive

Keywords:explosive, emulsion, dead-pressing, detonability

The detonability of a chemically gassed emulsion explosive has been studied. Blasting experiments in steel pipes and computer simulations have been carried out. This study showed that the tested explosive can tolerate a pressure of 17 MPa before it is dead-pressed. The explosive can also recover its detonability as soon as the compression vanishes. Furthermore, the computer simulation showed that the dead-pressing is a very rapid process, taking approximately 3 ms.
The detonability recovery time is very short, dependant upon the pressure release speed. These simulation results are consistent with the experimental evidence. This paper describes the properties of the explosive, the experimental design and procedure, the simulation principle and algorithm as well as the final results.

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