RU2052103C1 - Process of separation of blocks of natural stone - Google Patents

Abstract

FIELD: mining industry. SUBSTANCE: blast-holes are drilled in projecting planes of block separation, jaws are set in them in pairs. Jaws oriented to wards block separation are manufactured from high-strength material and have protrusions to form load of directed action. Jaws oriented to wards rock mass are made of damping material. Space between jaws is filled with high explosive. Apart from this jaws have dimension in cross-section not less than 0.87 diameter of blast- hole and springy members are installed between them. EFFECT: enhanced operational efficiency, reduced labour input. 3 cl, 3 dwg

Description

 The invention relates to the mining industry and can be used in the extraction of natural stone.

 A known method of separating blocks of natural stone, including drilling holes in the design plane of separation of the block, placing cheeks with longitudinal protrusions in them, filling holes with an explosive hardening expanding mixture. The disadvantage of this method is the low efficiency associated with the long term curing of expanding hardening compositions, and the inability to use in climatic conditions with subzero temperatures.

 The closest to the proposed technical essence and the achieved result is a method that includes drilling holes in the design plane of separation of the block, pairing them with damping gaskets made of wood, filling the space between them with gunpowder [2] The disadvantage of this method is the high cost associated with wasteful use of energy explosion and the great difficulty of using this method in flooded conditions.

 The aim of the invention is to reduce costs by increasing the distance between the holes.

 This is achieved by the fact that, in contrast to the known method, including drilling holes in the project area of separation of blocks, pairwise placement and orientation parallel to the project plane of separation of blocks of cheeks, one of which, oriented towards the array, is made of damping material, filling the space between the cheeks with a low screen BB, in the proposed method, the cheeks are oriented towards the detachable block, made of 40X steel, while the cheeks have protrusions to form a directed load in the rock. In addition, the cheeks have a cross-sectional dimension of at least 0.87 hole diameter. Between the cheeks spring elements.

 In FIG. 1 shows a drilled block on a ledge, general view; figure 2 hole, a longitudinal section; figure 3 hole, cross section.

 The method is as follows. When extracting natural stone, drill holes are drilled in the design planes for block breaking 1. Then, pair cheeks 2, 3 are placed in each hole, separated by flat springs 4, orienting them parallel to the design plane of separation of block 6, while the cheeks 3, oriented towards the detachable side blocks are made of steel 40X and have projections to form a directed load in the rock 5, and the cheeks 3, oriented towards the array, are made of damping material (wood), the space between the cheeks is filled low-explosive explosive (or DP) 7. After the assembly of the assembled chain is initiated, pressure is generated almost simultaneously in all holes, which propagates in all directions from the charge to the walls of the hole (in places where there are no cheeks) and to the cheeks located in the hole (and the impact load) .

 In those areas where the cheeks of damping material are located, the shock load is absorbed, thereby reducing (or eliminating in general) the region of crack formation. In the direction where the cheeks 3 of 40X steel are located, due to the protrusions 5, directed loads are formed, thereby contributing to the separation of the formed block from the array (eliminating the possibility of radial cracks as if these cheeks were absent).

 In the direction where there are no cheeks, pressure is transmitted to the walls of the hole, forming crushing zones that will be located along the line of separation of the block from the array, thereby creating favorable conditions for this process.

In order to avoid the possibility of explosion work as free plane angle formed by the segment relative to the center of the hole (in the free hole) should be at least ^about 58 (the minimum angle of the formation of explosive funnel, i.e. charge camouflet operates at smaller angles).

Based on these conditions, the minimum size of the flat part of the cheeks is determined by:
a ≥ 2r cos 29 ^o 1.74 r 0.87 d _dp , where r is the borehole radius, m;
d _sp diameter of the hole, m

где l расстояние, на котором необходимо бурить шпуры друг от друга в строчках, м;
Р_вв давление, создаваемое продуктами, МПа;
σ_р предел прочности пород на разрыв отделяемого массива, МПа;
К_э коэффициент, учитывающий материл энергопередающей среды между ДШ и щеками: для воды К_э 1; для песка К_э 1,5; для воздуха К_э 2; остальные обозначения те же.The pressure created from one thread of the DSh is 400 MPa (for DSH brands DShA, DShV). Thus, it is possible to determine the distance at which it is necessary to drill holes (in lines),
l

where l is the distance at which it is necessary to drill holes from each other in lines, m;
P _BB pressure created by products, MPa;
σ _r ultimate rock tensile strength of the separated massif, MPa;
K _e coefficient taking into account the material of the energy transfer medium between the DS and the cheeks: for water K _e 1; for sand K _e 1.5; for air K _e 2; the remaining notation is the same.

+ 1 где N_шп количество шпуров в ряду, м (округляется в большую сторону до целого числа).Then the number of holes needed to separate the block, the edge length of which is determined from the expression
N _sp =

+ 1 where N _{sp the} number of holes in a row, m (rounded up to an integer).

0,61 м.PRI me R. It is necessary to separate the block, the length of the ribs of which is 4 m, the diameter of the holes drilled along the contour is 0.042 m; tensile strength of rocks 12 MPa; filler air; as a VV DSHA. Then the distance between the holes in the row is
l

0.61 m.

+ 1 6,1+ + 7,1
Принимаем 8 шпуров. После отделения блоков щеки из стали 40Х используются повторно. Количество выступов на щеках может меняться. Криволинейная поверхность щек из стали 40Х может быть снабжена обкладкой (для удобства монтажа и снятия ударных нагрузок).The total number of holes on one face of the determined block:
N _sp =

+ 1 6.1+ + 7.1
We accept 8 holes. After separating the blocks, the cheeks from 40X steel are reused. The number of protrusions on the cheeks may vary. The curved surface of the cheeks made of steel 40X can be provided with a lining (for ease of installation and removal of shock loads).

 In order to ensure reliable contact between the cheeks and the detachable array and increase the accuracy of their orientation, spring elements are placed between them.

 Thus, the present invention has the following advantages: the method is simple and economical, it allows to increase the output of air-conditioning units during stone mining; production costs are reduced.

Claims (3)

 1. METHOD FOR SEPARATING NATURAL STONE BLOCKS, including drilling holes in the project area for separating blocks, pairing in holes and orientation parallel to the project plane for separating cheek blocks, one of which is oriented towards the array and made of damping material, filling the space between the cheeks with a low-blast explosive, characterized in that the cheeks oriented towards the detachable block are made of steel, while the cheeks have protrusions to form a directed load in the rock.  2. The method according to claim 1, characterized in that the cheeks have a cross-sectional dimension of at least 0.87 diameter of the borehole.  3. The method according to PP.1 and 2, characterized in that between the cheeks set springing elements.

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