Method for explosive loosening of hard rocks using charges with air cushion
SUBSTANCE: method involves drilling of blast holes with increased subdrilled area, their charging with an air cushion arranged in the above subdrilled area, and explosion of mine rocks. Air cushion with length of 6-10 diameters of the well is created below actual level of bench bottom by 2-3 diameters of the well. Additional charge with length of 10-20 diameters of the well is arranged under the cushion.
EFFECT: improving the efficiency of charges.
The invention relates to the field of mining industry, in particular to the development of strong rocks in difficult conditions when excessive resistance on the soles of the ledge or marking soles, etc.
Widely known methods of explosive loosening of rocks with a separation of charge on the part of the air gaps . Increasing the exposure time of the pulse of the explosion on the array decreases pereselenie near charge, which contributes to a significant improvement of the quality of crushing while reducing specific consumption of EXPLOSIVES.
It is also known that the location of the air gap at the bottom end of the charge, creating an air cushion, in addition to a significant increase in quality crushing, excludes reverse ejection blasted rock at the upper edge of the ledge, at the expense of directional emission of the rock mass in the direction of the slope of the ledge is exposed almost half and has a steeper angle .
Our studies revealed that the charges with an air bag, allow to work excessive resistance on the soles of the ledge and even when inflating the foot of the escarpment can achieve a qualitative study of the soles of the ledge when the design change charge.
The closest essentially a solved problem is the way of the explosive loosening rocks with an air bag, in which air p is dushku place in the advanced drilled part of the well, below the design elevation of perebor [2, P80]. The disadvantage of this method is inflated value of perebor - up to 5.5 m (22-25 diameter wells)when the length of the airbag 3 m (12-14 diameter wells).
The technical task to be solved by the invention, is to increase the efficiency of the charge air cushion in conditions of excessive resistance to the action of an explosion through the use of a special construction of the explosive charge.
This object is achieved in that in the method of explosive loosening rock charges with an air bag, comprising the drilling of blastholes with increased pereboom, their loading with accommodation in peribere airbags and blasting of rocks, according to the invention an air cushion length 6-10 diameter wells are placed below the actual level of bench bottom 2-3 diameter of the hole, and below it place additional explosive charge length 10-20 diameters of the well.
The implementation of the method presented in the diagrams.
Figure 1 presents the design of the charge; figure 2 shows a video frame of the explosion borehole charges with air cushion of foamed polystyrene, figure 3 - view of the face and the collapse of the rock mass after the explosion.
The way of the explosive loosening rock charges with air cushion as follows.
At the mouth of the PE 1 drilling of wells 2 by the calculation grid with increased pereboom. Then proceed to the formation of a charge of air cushion in peribere. To do this, first place the lower action 3 on the conductor initiating impulse 4, such as detonating cord (LH) or waveguide system SINV and form the lower explosive charge 5 length 10-20 diameters of the borehole. Above it creates an air cushion 6 length 6 to 10 diameters of the borehole, for example, falling asleep polystyrene foam, with the top mark airbag 6 should be 2-3 diameters well below the soles of the ledge 7. Then in the borehole 2 post action 8 on the conductor initiating impulse 9 for the upper charge 10, after which form the stemming 11. The length of the bottom of the battery 5 and the airbag 6 pick empirically depending on the tasks. So, at highly inflated level 7 soles increase the length of the lower charge, while a high resistance on the soles of the ledge increase the length of the airbag 6. After charging all wells mounted explosive network. Preferred contractor scheme with longitudinal rows in the direction of the slope of the escarpment.
When the detonations of conventional charge air cushion of the incident shock wave, reaching the bottom of the borehole, is reflected by the products of the detonation propagates the reflected shock wave with sharply increased in 10 times the pressure on her front, and can result in favorable the conditions for the best separation on the bench bottom [2, p.46]. In charge of the proposed design interact with the shock wave and the gas flows from the two charges, as a result, according to , the pressure in the air gap increases in 15-20 times, significantly increasing the duration of the explosive impulse and isolation breeds over sole ledge increase. This assumption was confirmed experienced an explosion using charges with the suggested settings below the foot of the escarpment. When inflating the foot of the ledge 5 meters blasted rock mass was discarded parallel to the surface of the working platform, revealing the slope of the ledge completely (see figure 3).
Thus, the inventive method explosive loosening rock charges with an air cushion by placing additional charge under air cushion in peribere provides a gap on the bottom of the ledge when blasting with high resistance parameters, thereby making it possible to solve the problem.
Sources of information
1. Marchenko, L.N., Kudryashov B.C. guidelines for the application of borehole charges, distributed air gaps on open mining /Coll. Explosive case No. 51/8. M.: Nedra, 1963. - S-206.
2. Zhunusov K. Blasting rock charges with air cushion. Alma-ATA, Nauka, 1979. P80-81 (prototype).
3. Gubkin V. the more effective is aktivnosti borehole charges with air gaps // the Problem of destruction of rocks by explosion. M.: Nedra, 1967, S-159.
The way of the explosive loosening rock charges with an air bag, comprising the drilling of blastholes with increased pereboom, their loading with accommodation in peribere airbags and blasting of rocks, characterized in that an air cushion length 6-10 diameter wells create below the actual level of bench bottom 2-3 diameter of the hole, and below it place additional explosive charge length 10-20 diameters of the borehole.
SUBSTANCE: method includes drilling vertical main wells, definition of a contour in plan and soil elevations of solid inclusions along the depth of the main wells, drilling additional vertical wells inside the contour of inclusions, charging main and additional wells with explosive charges, with placement of explosive charges in additional wells inside their inclusions and their blasting. Selection of explosive charge parameters for charging additional wells is carried out by the value of product of explosive detonation speed and explosive charge diameter defined from the ratio.
EFFECT: higher efficiency of solid inclusions grinding.
2 cl, 2 dwg
SUBSTANCE: block to be exploded is drilled around the perimeter of its connection to rock mass by means of a row of wells in 3-4 metres. At that, during preparation for drilling and explosion loosening the well rocks in the row are drilled to the depth below the coal formation through the distance excluding the formation destruction during explosion of row by means of base charge.
EFFECT: reducing the cost of rock mass to be exploded owing to using explosives non-resistant to water as a result of drying of the block to be exploded.
SUBSTANCE: method of blast-hole drilling ensuring preset extent of blast rock grinding includes drilling of explosive wells at the distance between them, depending on detonating characteristics of explosives, physical and technical properties of a rock massif, parameters of its cracking, their charging and explosion. Explosive wells are charged with explosives with specific consumption per m3 of blast rock in amount determined with account of explosive energy losses as charge explosion products expand in a well volume occupied with the charge, and also with account of losses related to the extent of the specific explosive detonation completeness in the well of the specific diameter, which are introduced into a calculation expression for a coefficient of relative operability of the applied explosive.
EFFECT: reduced volume of drilling works in drilling of explosive wells, which results in higher efficiency and reduced cost of blast-hole drilling.
SUBSTANCE: in the method to form charges in drowned wells, including drilling of wells, their filling with explosives and a plug from inertial materials, a multicharge is formed in wells filled with water, made of two different types of hose explosive charges. The main hose explosive charge with detonation speed corresponding to the speed of stress wave propagation in surrounding rock and weight of 75…80% from total mass of the multicharge is placed vertically along the well axis. The second hose explosive charge with high speed of detonation exceeding the speed of stress wave propagation in a rock massif and weight of 20…25% from the total mass of the multicharge, is placed along the spiral around the first hose charge, with a pitch of one turn along the vertical line equal to two well diameters. Linear initiation of the explosive multicharge is carried out simultaneously along the entire length of the well with a detonating chord with a charge of 40 g/m.
EFFECT: amplified amplitude of a voltage pulse and intensity of rocks grinding, which as a whole increases efficiency of drilling and blasting works with reduction of hazardous effect of explosion to environment.
5 cl, 1 dwg
SUBSTANCE: during performance of drilling and blasting works in the lower part of each explosive well a bottom charge is arranged, on the outer surface of which there is a circular cumulative groove arranged, the top of which lies in the horizontal plane, which separates the volume of the bottom charge in two and matches the plane of a working site of an open pit ledge or a bottom of an underground stope. The value of well subgrade drilling is accepted as equal to the half of the cumulative groove base width.
EFFECT: reduced drilling flow due to reduction of subgrade drilling and higher quality of arrangement of a working site of open pit ledges and a bottom of stopes at underground mining works.
SUBSTANCE: inclusions may be represented by layers of hard rocks, various lenses and other inclusions, such as permafrost (eternal frost) in less hard enclosing rocks. Explosive charges in additional shortened wells are placed at the level or below the soil of hard inclusions and are exploded with moderation relative to charges in the main wells. The proposed invention makes it possible to execute efficient grinding of solid inclusions that are previously softened by explosion of charges in the main wells, due to dynamic effect of explosive gases from explosion of charges in additional wells at the lower part of inclusions.
EFFECT: higher efficiency of grinding of various solid inclusions available in the upper and middle part of the ledge and arranged in less hard enclosing rocks.
2 cl, 2 dwg
FIELD: oil and gas industry.
SUBSTANCE: method for forming hose charge in wells involves well drilling, arrangement of hose charge in it and stemming by means of inert materials. At that, hose charge is made in the form of a spiral wound on thin-wall perforated plastic pipe, with winding pitch equal to 4.0…5.0 diameters of hose charge. Hose charge and detonating cord is attached to thin-wall perforated plastic pipe. After the assembled structure is arranged in the well, cavity of the pipe and gaps between coils of hose charge are filled with water to the level of hose charge and the well is stemmed with inert materials.
EFFECT: reducing the specific flow of an explosive, increasing the crushing efficiency of rock masses, and reducing the dust loading of ambient air.
SUBSTANCE: method comprises shot hole or bore-hole drilling, loading them with explosive material so that the bottom part of the shot hole the explosive material density or energy concentration would exceed the one in the wellhead of the shot hole. The mass of explosive material charge in the bottom part of the shot hole is calculated mathematically, depending on the line of least resistance value, the diameter of explosive material charge, fissure parameters and physical and technical mountain mass parameters, the rock pressure and detonation velocity of the explosive material.
EFFECT: enhanced efficiency and safety of drilling and blasting operations alongside with ore beneficiation efficiency.
1 dwg, 1 dwg
SUBSTANCE: suspended well stem comprises flat elements and an elastic link. At the same time flat elements are made as two hingedly joined half-discs joined to each other, length of each equals 0.55-0.7 dw, and width - 0.65-0.9 dw. At one side each element is rounded, following the well circumference. A rope is fixed to the hinged joint, so that the hinged joint is arranged at the bottom.
EFFECT: higher operational reliability of the device, intensified process of rocks grinding, reduced specific consumption of explosive, higher quality of rock mass grinding, simplified and cheaper design.
SUBSTANCE: during development of arrangement diagram of bore pits the location points of bottoms of bore pits are arranged on explosion plane on bottom-hole of set of bore pits. Programme product of design of arrangement diagram of bore pits determines absent parametres of bore pits considered from bottom-hole of set of bore pits to navigation plane. Programme product is capable of determining initial location point of bore pit and direction of bottom-hole. Programme product also makes explosion technical calculation of arranged bore pits.
EFFECT: method and programme product for development of arrangement diagram of bore pits is improved.
25 cl, 20 dwg
FIELD: mining art, in particular, open-pit mining of mineral resources by high benches.
SUBSTANCE: large-diameter single holes are replaced by a pair of divergent holes of a smaller diameter, in which one hole is always vertical, and the other one is inclined towards the bench; the single holes of the larger diameter are replaced with a pair of divergent bundles of parallel converged holes, in which one bundle is vertical, and the other is inclined towards the bench; the single holes of the larger diameter are replaced with a pair of divergent holes of a smaller diameter, in which one hole is vertical, and the other is inclined towards the bench and positioned in the vertical plane parallel with the first one and distant from it by 1-2 hole diameters; the single holes of the larger diameter are replaced by a pair of divergent bundles of parallel converging holes, in which one bundle is vertical, and the other is inclined towards the bench and positioned in the vertical plane parallel with the first one and distant from it by 1-2 hole diameters.
EFFECT: enhanced efficiency of blasting of the benches.
7 cl, 6 dwg
FIELD: mining industry, applicable in opencast mining of mineral resources and hydraulic engineering.
SUBSTANCE: the method for formation of a deep-hole charge of a multi-component mixed explosive consists in impregnation of porous and crystal ammonium nitrate with liquid petroleum product and placement of the obtained explosive in the hole, formation of the mentioned deep-hole charge in its extension is accomplished with sections of various density of the explosive depending the physico-mechanical properties of the rocks located in the length of the hole, varying the density of the explosive by varying the mass percent relation of the quantity of granules of porous and crystal ammonium nitrate in the explosive compound, the mass percent of a granule of porous ammonium nitrate is within 54.5 to 71.5, a granule of crystal ammonium nitrate is within 20 to 40, liquid petroleum product - within 5.5 to 8.5, the granules of porous ammonium nitrate are used with sizes of 2.5 to 4.5 mm, and those of crystal ammonium nitrate - 0.7 to 1.3 mm, mineral oil is used as petroleum product.
EFFECT: provided optimized destruction of the rock in opencast mining of mineral resources and in building blasting operations.
FIELD: mining industry, applicable for slanting of high benches at development of magmatic deposits of mineral resources by open pit.
SUBSTANCE: the method includes drilling of contour holes for formation of a screening peephole, buffer and breaking holes to a depth corresponding to the height of one working subbench with a redrill, the middle row of breaking holes is made with an incomplete drill, charging of the openings and their blasting, dispatch of the rock, after blasting first of outline openings, for formation of the screening peephole, and then of breaking holes and mucking of the rock, similar operations are performed on the underlying subbench of the lower high bench, at the development of the lower high bench, the development of the upper and lower benches is conducted by doubling of the working subbenches, at the development of the lower subbench of the upper high bench the outline openings are drilled to the whole height of the doubled bench, the buffer openings are drilled at a distance of 12 to 13 diameters of the charge from the outline openings and to a depth at least corresponding to the height of one working subbench with a redrill equal to 6-8 diameters of the charge, the first and last rows of the breaking holes are drilled with a redrill, equal to 4-5 diameters of the charge, and the incomplete drill of the middle row of the breaking holes makes up 7-8 diameters of the charge, after blasting of the buffer and breaking opening and mucking of the rock a crest is formed, from whose surface on the side of the slope outline and buffer openings are drilled, the first ones - to the height of doubled subbenches, and the second ones - to the height at least of one lower working subbench, then the breaking openings to the same height as in the above - and underlying subbenches and for production of a natural protective bank on the upper section of the lower high bench in the section of the berm the formed ridge is liquidated by drilling, charging and blasting of the openings of small diameter and depth.
EFFECT: enhanced stability of high benches on the outline of the open pit.
2 cl, 3 dwg, 1 ex
FIELD: mining industry, applicable at blasting of rocks on the ground surface, at blasting of ores in the underground conditions and driving of underground open pit minings.
SUBSTANCE: the method for drilling blasting of rocks includes drilling of boreholes with subsequent their loading with explosive charges, short-delay blasting and registration of seismic oscillations on one block. Then, the zone with the maximum quantity of simultaneously blasted deep-hole charges on this block is determined according to the amplitude of speed exceeding the preset level on the seismograph. After that the intervals of operation between the adjacent charges on the next block are increased with due account made for the obtained results of measurements on the previous block.
EFFECT: provided the necessary degree of rock crushing at an allowable level of seismic action on the environment.
4 dwg, 1 ex
FIELD: mining of mineral raw material, applicable at opening of workings or manbreaking.
SUBSTANCE: a trapezoidal recess is made in the cartridge-shape charge of blasting destruction obliquely to the longitudinal axis of the charge. The recess is positioned at the cut of the generating line and the change end face. In the charged blast-hole (or well) the recess is directed towards the non-charged blast-hole or towards the additional exposed plane.
EFFECT: enhanced utilization factor at opening of workings and holes at mass breaking.
SUBSTANCE: method comprises making well charge of individual members of the blasting agents that receive one or several strikers. The members are separated with spaces filled with a liquid with a density of 800-1400 kg/m3. The strikers are actuated so that the detonation of blasting agent is completed simultaneously in the bulk. The height of the active section of the charge of blasting agent interposed between the boundaries of the liquid and location of the striker are calculated from the formula proposed.
EFFECT: enhanced efficiency.
7 cl, 3 dwg
FIELD: mining industry; openpit mining of ferruginous quartzites.
SUBSTANCE: method is proposed in two versions. According to first version, method includes drilling at bench parallel rows of vertical boreholes at angle β relative to strike line of layers determined by the following relationship: β=arc cos (cos 45°-sinγ·cosα)/(sinα·cosγ), where α is angle of dip; γ is angle between plane of blast wave front and vertical. Then, boreholes are charged with explosive followed by tamping at simultaneous blasting in each row for forming inclined compression blast wave. According to second version, proposed method includes drilling parallel rows of vertical boreholes at angle β relative to strike line determined by the following relationship: β= arc cos (cos 45°-sinγ·cosα/(sinα·cosγ)±ψ, where α is angle of dip; γ is angle between plane of compression blast wave front and vertical; ψ is angle of turn of compression blast wave front around vertical axis relative to strike line which is determined as follows: ψ=arc sin(υel·t/L) where υel is velocity of propagation of elastic wave in mass; t is interval of time between blasts of charges in first and last boreholes of row; L is length of this row of boreholes; sign of angle ψ is selected that angle between line of each row of boreholes and line of crest of bench of shoulder is close to or is equal to 90°, after which boreholes are charged with explosive followed by tamping and successive blasting in each row forming inclined compression blast wave.
EFFECT: enhanced efficiency of softening the ore.
3 cl, 6 dwg, 3 ex
FIELD: mining; construction industry; methods of breaking rocks from massifs with lenticular permafrost massifs.
SUBSTANCE: the invention is pertaining to the field of mining and construction and is intended for breaking rocks from massifs with the lenticular permafrost spots. The technical result is improvement of the quality of crushing of rocks with the lenticular permafrost spots and a capability to control the sizes of the crushing over the whole volume of the rocks shooting. The method provides for boring of the downward primary and additionally boreholes, their charging with explosive charges (explosives), stemming of boreholes and firing of charges of explosives. At that while boring the primary boreholes in the case of presence of the lenticular permafrost spots determine their contours in plane and marks of the roofing and soil of these lenticular permafrost spots by the depth of the boreholes. The additional boreholes they drill inside the contour with a crossover of the indicated lenticular permafrost spots, but not deeper than the primary boreholes, At that determine marks of the roofing and soil of the lenticular permafrost spots by the depth of the additional boreholes, and at a charging of the additional boreholes the charges of explosives place inside the crossing lenticular permafrost spots.
EFFECT: the invention ensures improvement of the quality of crushing of rocks with the lenticular permafrost spots and a capability to control the improvement of the quality of crushing of rocks with the lenticular permafrost spots and a capability to control the sizes of the crushing over the whole volume of the rocks shooting.
8 cl, 2 dwg, 4 ex
FIELD: mining art, applicable for mining by open method in rocky and semirocky rocks at placing of high benches on planned contour.
SUBSTANCE: the method consists in collaring of inclined holes from the upper bench to be height of a doubled bench, for production of a cut-off slot at formation of the upper inclined part of the bench and contour vertical holes from the intermediate bench to the same depth for formation of the lower vertical part of the bench, loading and blasting. The novelty in the method is in the fact that the drilling of holes of the contour row from the intermediate bench is performed in three stages: initially in the first stage drilled is the part, of inclined holes from the initial to the final point of the section of sloping with one direction of inclination, in the second stage drilled are the inclined holes of the contour row having the same inclination and the same distance between the holes as in the first stage, but in the contrary direction, in the third stage between the mentioned inclined contour holes drilled are vertical contour holes, the inclined holes of the contour row are loaded by a permanent charge from the face to the mouth of the holes, and in the vertical contour holes positioned between the inclined contour holes, the amount of the charge is changed successively from the face to the mouth, corresponding to the minimum distance between the inclined and vertical contour holes at the bottom of the lower bench is the minimum charge in the vertical contour hole, which in proportion with removal from the bottom of the lower bench successively increases, reaching its maximum value at the bottom of the intermediate bench, at the maximum distance between the inclined and vertical contour holes at the bottom of the lower bench the value of the charge in the vertical contour hole from the face to the mouth is changed in the reverse order.
EFFECT: enhanced efficiency of sloping.
7 dwg, 1 tbl
FIELD: mining industry, applicable in driving of horizontal workings.
SUBSTANCE: compensation and blast holes are drilled in a rock mass over the entire length of the raise. The blast holes are charges partially or completely, and they are subjected to a short-delay blasting into compensation holes and then the formed compensation cavities. The interval of slowing-down between the holes blasted in succession, depending on the detonation characteristics of the explosive, charge diameter, physico-technical properties of the rock mass, height and diameter of the newly formed compensation cavities should provide for breaking of the rock from the mass and full outburst of the rock mass from the cavity, i.e. to prevent the pressing effect of the rock mass in the contour of the raise.
EFFECT: determined the interval of slowing-down between the holes blasted in succession with prevention of the rock mass pressing in the contour of the raise, which allows to increase the height of the blasted section and enhance the physico-technical properties of the raise driving.
1 dwg, 1 ex, 2 tbl