A diamond wire saw cutting and blasting combined well construction method

Abstract

The present invention discloses a diamond wire saw cutting and blasting combined well-forming method, (1) designing a rectangular well section according to ventilation requirements and geological conditions, designing a number of guide holes for vertical excavation from top to bottom; setting one or two of the guide holes as drilling process inspection pretreatment holes, performing drilling process inspection pretreatment on them, detecting the reliability of the drilling process, and obtaining the process parameters of each round of well-forming cutting and drilling; (2) accurately drilling the well section; (3) using a diamond wire saw to sequentially cut the edge line of the well in a first horizontal and then vertical manner to form a suspended rock block; (4) performing segmented blasting to drop the ore to form a well. The present invention has the advantages of high safety and smooth and regular well wall, and can greatly reduce the labor intensity, reduce the working time exposed to the working surface, facilitate the subsequent recovery and effectively control the mining width of the ore vein, and provide a technical basis for reducing the mixing of waste rock.

Description

Technical Field

[0001] The invention belongs to the technical field of shaft excavation in underground mining operations, and in particular relates to a diamond wire saw cutting and blasting combined shaft forming method. Background Art

[0002] The skylight is an important project that is indispensable for underground mining. Traditional skylight construction methods generally include common method, hanging tank method or climbing tank method. The three have common disadvantages, that is, the workers all work in the well, the site is a single-head working face, and there are disadvantages such as poor ventilation, high labor intensity, low efficiency and poor safety.

[0003] Chinese patent CN113432497A discloses a one-time well blasting method for deep skylight, including filling concrete in the interval of 0.2m to 0.4m from the bottom of the hole, and filling a first filling layer above the concrete; laying a first layer of explosive packages above the first filling layer, wherein the first layer of explosive packages is provided with detonators; laying a second filling layer above the first layer of explosive packages; laying a second layer of explosive packages above the second filling layer, wherein the second layer of explosive packages is provided with detonators; laying a third filling layer above the second layer of explosive packages; connecting the blasting device to the detonators in the first layer of explosive packages and the detonators in the second layer of explosive packages respectively; and delaying the detonation of the first layer of explosive packages and the detonators in the second layer of explosive packages by the delayed detonator in the blasting device to complete the one-time well blasting of the deep skylight. The use of this patent can solve the various safety hazards existing in the current deep skylight construction method.

[0004] Chinese patent CN110307762 B discloses a method for rapid well construction based on deep hole hole-by-hole blasting technology, which includes the following steps: Step A1: Around the well project, the well connection level tunnels are excavated at both ends of the well to form upper and lower construction working surfaces; then the shaft center line of the well is calibrated and laid out according to the engineering design; Step A2: The lower well connection level tunnel is expanded and top pressed, and the lower construction working surface is blasted with shallow holes to form a chamber space with a volume of V on the lower working surface; Step A3: Arrange blast holes along the cross section of the well, the number of blast holes is N, of which B blast holes are charge holes, and the other NB blast holes are large-diameter empty holes; the large-diameter empty holes are arranged in a rhombus; the B charge holes are divided into a core hole and a first charge hole layer, a second charge hole layer, and a third charge hole layer according to their orientation, and each charge hole layer has C blast holes; then charge is charged according to the design and then blasted to form a well. The patent can quickly generate a usable patio by blasting.

[0005] Although the above patent has improved safety, the rock fragments are large, the well construction cost is high, and the well construction is irregular, making it unsuitable for promotion and application. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide a diamond wire saw cutting and blasting combined well-drilling method, which can meet the current national requirements for improving the safety and efficient production level of mines, and at the same time has the advantages of high safety and smooth and regular well walls, and can greatly reduce labor intensity and reduce the working time exposed to the working surface, which is convenient for subsequent recovery and effectively controls the mining width of the ore vein, and provides a technical basis for reducing the mixing of waste rock.

[0007] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0008] A diamond wire saw cutting and blasting combined well construction method comprises the following steps:

[0009] (1) A rectangular shaft section is designed according to ventilation requirements and geological conditions, and several guide holes are designed to be excavated vertically from top to bottom; one or two of the guide holes are set as drilling process inspection pretreatment holes, and drilling process inspection pretreatment is performed on them to detect the reliability of the drilling process and obtain the process parameters of each round of well cutting and drilling;

[0010] (2) Precise drilling of the patio section;

[0011] (3) Use a diamond wire saw to cut the edge line of the skylight in a first horizontal and then vertical manner to form a suspended rock block;

[0012] (4) Carry out segmented blasting to form a shaft.

[0013] Preferably, in step (1), the rectangular shaft section is divided into blocks, which are sawn and blasted block by block.

[0014] Preferably, the block section size is controlled within 2.0m×2.0m.

[0015] Preferably, the method for precise drilling in step (2) is: select the drill bit model according to the construction conditions of the rope saw machine and the later blasting requirements, use the tunnel drilling rig to drill the remaining guide holes respectively, and control the drilling pressure, rotation speed and return time of the drilling rig.

[0016] Preferably, the hole spacing of the drilled holes is ≥400 mm.

[0017] Preferably, when detecting the drilling reliability, the vertical up and down drilling horizontal offset is ≤0.15m.

[0018] Preferably, in step (3), the specific cutting method is:

[0019] S1: Start cutting the three side lines of the skylight with a rope saw, first cut the two horizontal sides, then cut the one vertical side, so that the skylight forms a suspended rock mass;

[0020] S2: Diamond wire rope is lifted upward from bottom to top to saw the suspended rock mass. When the diamond wire rope reaches the designed length, it is cut off. Then the wire saw machine is driven back to the original starting position for cutting. The diamond wire saw is reconnected and set, until the top of the upper tunnel is sawed.

[0021] S3: Divide the rock mass within the cutting edge into a number of horizontal segments, and then into a number of vertical segments, and repeat the sawing in step S2 until the horizontal and vertical sawing are completed.

[0022] Preferably, in step (4), the specific method of segmented blasting is: divide the shaft into several sections in the vertical direction, load explosives according to a pre-designed detonation sequence, and use a method of downward blasting with slight differences in layers inside and outside the layer and upward blasting or a method of bi-directional blasting with slight differences in layers inside and outside the layer and bi-directional blasting to implement blasting and mine dropping.

[0023] Preferably, in step (4), the detonation order of the staged blasting is: groove hole → auxiliary hole → peripheral hole.

[0024] Preferably, in step (4), the depth of the well is 10 to 50 m.

[0025] Preferably, the diamond wire saw cutting and blasting combined well-building method is suitable for well-building operations of advanced wells, cutting slot wells, chute wells, and ventilation wells.

[0026] The present invention has the following advantages:

[0027] The present invention adopts the combined well-forming technology, which firstly overcomes the problems of poor safety, high labor intensity and low efficiency of the existing skylight construction methods; secondly, the blockiness of the fallen ore and rock debris is effectively controlled, eliminating the problem of high subsequent processing costs such as secondary crushing; thirdly, the skylight is neatly formed, the skylight wall is smooth and there is less pumice.

[0028] According to the existing equipment and blasting technology, the cross-sectional size of the blocks is controlled within 2.0m×2.0m, the size of the rock slag in the skylight can be effectively controlled, and the frequency of the secondary crushing link is greatly reduced, which not only facilitates the shoveling and transportation of the slag but also reduces costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 A top view of the drilling arrangement of Example 1;

[0030] Figure 2 A top view of the drilling arrangement of Example 2;

[0031] Figure 3 This is a top view of the drilling arrangement of Example 3. DETAILED DESCRIPTION

[0032] In order to facilitate a better understanding of the present invention, the following examples are used to illustrate the present invention. These examples belong to the protection scope of the present invention, but do not limit the protection scope of the present invention.

[0033] Example 1

[0034] A diamond wire saw cutting and blasting combined well construction method comprises the following steps:

[0035] (1) According to the geology, occurrence conditions and ventilation requirements of the tunnel ore body, a rectangular advanced shaft section with a size of 3.5m×1.2m was designed. It was divided into two areas, block A and block B, for sawing. The sizes were 2.0m×1.2m and 1.5m×1.2m respectively. Six vertical guide holes were designed from top to bottom, namely 1#, 2#, 3#, 4#, 5# and 6#, and 13 pre-blasting holes with a hole spacing of 400mm. The first sawing surface was selected, a small rectangular 1.5m×1.2m block A, with edge lines of 1#2#3#4#; 7# was set as the drilling process inspection pretreatment hole, and the drilling process inspection pretreatment was performed on it to detect the reliability of the drilling process, such as Figure 1 As shown in the figure, the horizontal deviation of vertical up and down drilling is ≤0.15m, and the process parameters of each round of well cutting and drilling are obtained;

[0036] (2) According to the construction conditions of the rope saw machine and the later blasting requirements, select Drill bit: Use a tunnel drill to accurately drill holes in the skylight section. Use the tunnel drill to drill six guide holes 1#, 2#, 3#, 4#, 5#, and 6#, respectively. The drilling efficiency is 3m / h, the rated drilling pressure is 8Mpa, the speed is 115r / min, the rated torque is 350N·m, and the water supply pressure is 0.8Mpa.

[0037] (3) Use a diamond wire saw to cut the three edge lines of the skylight in block A in sequence, first horizontally and then vertically, 1#2#, 3#4#, and 1#4#, to form a suspended rock block; cut the diamond wire from bottom to top by lifting and sawing for 10m, then cut the diamond wire, and then drive the wire saw back to the original starting position for cutting, reconnect and set the diamond wire saw for cyclic cutting until the top of the skylight in the upper tunnel is sawed; divide the rock mass within the cutting edge into several horizontal segments, and then into several vertical segments, and repeat the above sawing until the horizontal and vertical sawing are completed;

[0038] (4) According to the geological conditions of the surrounding rock, the skylight is divided into sections from bottom to top in the vertical direction. The blasting is carried out by layered blasting. The explosives are loaded in the order of slot hole → auxiliary hole → peripheral hole. The method of blasting the ore downward and upward with slight difference in layers inside and outside the layer is adopted to implement blasting. After the blasting is completed, the ore is removed and the remaining rectangular block B is sawed and blasted in sections according to the cutting method of the first rectangular block until the skylight is formed. The depth of the skylight is 24m.

[0039] Example 2

[0040] A diamond wire saw cutting and blasting combined well construction method comprises the following steps:

[0041] (1) According to the geology, occurrence conditions and ventilation requirements of the tunnel ore body, a rectangular advanced shaft section with a size of 3.5m×2.0m was designed. It was divided into two areas, block A and block B, for sawing. The sizes were 2.0m×2.0m and 1.5m×2.0m respectively. Six vertical guide holes were designed from top to bottom, namely 1#, 2#, 3#, 4#, 5# and 6#, and 23 pre-blasting holes with a hole spacing of 500mm. The first sawing surface was selected, a small rectangular 1.5m×2.0m block A, with edge lines of 1#2#3#4#; 7# was set as the drilling process inspection pretreatment hole, and the drilling process inspection pretreatment was performed on it to detect the reliability of the drilling process, such as Figure 2 As shown in the figure, the horizontal deviation of vertical up and down drilling is ≤0.15m, and the process parameters of each round of well cutting and drilling are obtained;

[0042] (2) According to the construction conditions of the rope saw machine and the later blasting requirements, select Drill bit: Use a tunnel drill to accurately drill holes in the skylight section. Use the tunnel drill to drill six guide holes, namely, 1#, 2#, 3#, 4#, 5#, and 6#. The drilling efficiency is 4m / h, the rated drilling pressure is 8Mpa, the speed is 115r / min, the rated torque is 350N·m, and the water supply pressure is 1.2Mpa.

[0043] (3) Use a diamond wire saw to cut the three edge lines of the skylight in block A in sequence, first horizontally and then vertically, to form a suspended rock block; cut the diamond wire from bottom to top by lifting and sawing for 10m, then cut the diamond wire, and then drive the wire saw back to the original starting position for cutting, reconnect and set the diamond wire saw for cyclic cutting until the top of the skylight in the upper tunnel is sawed; divide the rock mass within the cutting edge into several horizontal segments, and then into several vertical segments, and repeat the above sawing until the horizontal and vertical sawing is completed;

[0044] (4) According to the geological conditions of the surrounding rock, the skylight is divided into sections from bottom to top in the vertical direction. The blasting is carried out by layered blasting. The explosives are loaded in the order of slot hole → auxiliary hole → peripheral hole. The method of blasting the ore downward and upward with slight difference in layers inside and outside the layer is adopted to implement blasting. After the blasting is completed, the ore is removed and the remaining rectangular block B is sawed and blasted in sections according to the cutting method of the first rectangular block until the skylight is formed. The depth of the skylight is 50m.

[0045] Example 3

[0046] A diamond wire saw cutting and blasting combined well construction method comprises the following steps:

[0047] (1) According to the geology, occurrence conditions and ventilation requirements of the tunnel ore body, a rectangular ventilation shaft section is designed with a size of 4.0m×2.0m. It is divided into two areas, block A and block B, for sawing. The size of each area is 2.0m×2.0m. Six vertical guide holes are designed from top to bottom, namely 1#, 2#, 3#, 4#, 5#, and 6#. There are 27 pre-blasting holes with a hole spacing of 500mm. The first sawing surface block A is selected, and the edge lines are 1#2#3#4#; 7# is set as the drilling process inspection pretreatment hole, and the drilling process inspection pretreatment is performed on it to detect the reliability of the drilling process, such as Figure 3 As shown in the figure, the horizontal deviation of vertical up and down drilling is ≤0.15m, and the process parameters of each round of well cutting and drilling are obtained;

[0048] (2) According to the construction conditions of the rope saw machine and the later blasting requirements, select Drill bit: Use a tunnel drill to accurately drill holes in the skylight section. Use the tunnel drill to drill six guide holes, namely, 1#, 2#, 3#, 4#, 5#, and 6#. The drilling efficiency is 3.6m / h, the rated drilling pressure is 8Mpa, the speed is 115r / min, the rated torque is 350N·m, and the water supply pressure is 1.1Mpa.

[0049] (3) Use a diamond wire saw to cut the three edge lines of the skylight in block A in sequence, first horizontally and then vertically, 1#2#, 3#4#, and 1#4#, to form a suspended rock block; cut the diamond wire from bottom to top by lifting and sawing for 10m, then cut the diamond wire, and then drive the wire saw back to the original starting position for cutting, reconnect and set the diamond wire saw for cyclic cutting until the top of the skylight in the upper tunnel is sawed; divide the rock mass within the cutting edge into several horizontal segments, and then into several vertical segments, and repeat the above sawing until the horizontal and vertical sawing are completed;

[0050] (4) According to the geological conditions of the surrounding rock, the skylight is divided into sections from bottom to top in the vertical direction. The blasting is carried out by layered blasting. The explosives are loaded in the order of slot hole → auxiliary hole → peripheral hole. The method of blasting the ore downward and upward with slight difference in layers inside and outside the layer is adopted to implement blasting. After the blasting is completed, the ore is removed and the remaining rectangular block B is sawed and blasted in sections according to the cutting method of the first rectangular block until the skylight is formed. The depth of the skylight is 13m.

[0051] Comparative Example 1

[0052] The well construction method of the raise drilling rig includes the following steps:

[0053] (1) The advanced shaft section is designed according to the geology of the ore body, the conditions of the ore vein occurrence and the ventilation requirements. The surveying personnel mark the center hole of the shaft on site and excavate downward from the center hole according to the designed inclination angle. During the pilot hole excavation process, the drilling parameters should be reasonably selected according to the rock formation conditions. During the drilling process, attention should be paid to the rotation speed, penetration and mud removal conditions;

[0054] (2) A stabilizer should be installed every 10 m of pilot hole drilling, and the inclination should be measured every 20 m. When the pilot hole passes through soft and hard interlayers, a small drill should be used to reduce the drilling speed;

[0055] (3) After the pilot hole is excavated in place, the cutterhead is installed and the hole is expanded upward in the reverse direction. The rock slag and magma at the bottom of the well should be removed in time;

[0056] (4) After the patio is formed, install the staircase platform from bottom to top according to the design requirements.

[0057] Comparative Example 2

[0058] The manual well digging method from top to bottom includes the following steps:

[0059] (1) A rectangular advanced shaft section is designed according to the geology of the ore body, the conditions of the ore vein occurrence and the ventilation requirements of the mining area. The shaft is divided into a hoisting room and a ladder room. The hoisting room is used to lift rock slag and materials, and the ladder room is used for personnel to go up and down. Before the shaft is excavated, the surveyor marks the four corner holes of the shaft on site and excavates downward. The center line of the shaft should be checked every 5m of excavation;

[0060] (2) The blastholes are cut in a wedge shape, and the depth of the cut should not exceed 1.5 m. When encountering a large number of surrounding rock slides during excavation, more holes should be drilled and less explosives should be loaded;

[0061] (3) After the well mouth is excavated 3m downward, cement masonry is required within the 2.5m area of ​​the well mouth to harden the mouth, and installation of lifting equipment and anti-fall facilities;

[0062] (4) The first pedestrian access road to the mining area (cross-section of 2.0 m × 2.0 m) is located 3.5 m below the opening of the skylight, and pedestrian access roads are subsequently excavated every 4 m to lead to the mining area.

[0063] (5) When digging the skylight downwards, a temporary staircase platform must be built. Once the skylight is excavated through, the staircase platform must be disassembled and assembled piece by piece from bottom to top according to the design requirements.

[0064] Comparative experiment

[0065] The safety, operating efficiency and cost, rock chip size control, forming regularity, smoothness and pumice, and applicable cross-sectional shape of Examples 1 to 3 and Comparative Examples 1 to 2 were evaluated respectively, and the evaluation results are shown in the following table.

[0066]

[0067] It can be seen from the above table that the well-forming methods of Examples 1 to 3 of the present invention have high safety, high operating efficiency, low cost, large and uniform rock fragments, and are convenient for shoveling; the formation is regular, smooth, with less pumice, and the cross-section is rectangular. The safety, operating efficiency, rock fragment size control, forming regularity, smoothness, and pumice situation of the well-forming method of Example 1 using a reverse drilling rig are comparable to those of the present invention, but the cost is high and the cross-sectional range is different. The safety and rock fragment size control of the well-forming method using manual digging from top to bottom of Example 2 are comparable to those of the present invention, but the operating efficiency is slow and the cost is high, the forming regularity decreases, the well wall is not smooth, and the applicable well-forming section is different from that of the present invention. It can be seen that the well-forming method of the present invention is superior to the well-forming method using a reverse drilling rig and the well-forming method using manual digging from top to bottom, and is more convenient for effective control of subsequent mining vein amplitudes.

[0068] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A diamond wire saw cutting and blasting combined well construction method, characterized in that: The following steps are involved: (1) According to the ventilation requirements and geological conditions, a rectangular shaft section is designed, and the rectangular shaft section is divided into blocks, which are sawed and blasted one by one. The size of the block section is controlled within 2.0m×2.0m; a number of vertical guide holes are designed from top to bottom, and one or two of the guide holes are set as drilling process inspection pretreatment holes. The drilling process inspection pretreatment is performed on them to detect the reliability of the drilling process, and the process parameters of each round of well cutting and drilling are obtained; (2) Precise drilling of the patio section; (3) Use a diamond wire saw to cut the edge line of the skylight in a horizontal and then vertical manner to form a suspended rock block; the specific cutting method is: S1: Start cutting three side lines of the skylight with a rope saw, first cut two horizontal sides, then cut one vertical side, so that the skylight forms a suspended rock mass; S2: Diamond wire rope is lifted upward from bottom to top to saw the suspended rock mass. When the diamond wire rope reaches the designed length, it is cut off. Then the wire saw machine is driven back to the original starting position for cutting. The diamond wire saw is reconnected and set, until the top of the upper tunnel is sawed. S3: Divide the rock mass within the cutting edge into a number of horizontal segments, and then into a number of vertical segments, and repeat the sawing in step S2 until the horizontal and vertical sawing are completed; (4) Carry out segmented blasting to drop the ore and form a shaft. The specific method of segmented blasting is to divide the shaft into several sections in the vertical direction, load the explosives according to the pre-designed detonation sequence, and use the method of throwing the slag downward and blasting upward with slight differences inside and outside the layer or the method of throwing the slag in both directions and blasting in both directions to implement blasting.

2. The diamond wire saw cutting and blasting combined well construction method according to claim 1, characterized in that: The method for accurate drilling in step (2) is as follows: select the drill bit model according to the construction conditions of the rope saw machine and the later blasting requirements, use the tunnel drilling rig to drill the remaining guide holes respectively, and control the drilling pressure, rotation speed and return time of the drilling rig.

3. The diamond wire saw cutting and blasting combined well construction method according to claim 1, characterized in that: The hole spacing of the drilled holes is ≥400mm.

4. The diamond wire saw cutting and blasting combined well construction method according to claim 1, characterized in that: When testing the reliability of the drilling process, the vertical horizontal deviation of the upper and lower drilling holes is ≤0.15m.

5. The diamond wire saw cutting and blasting combined well construction method according to claim 1, characterized in that: In step (4), the detonation order of the staged blasting is: slot hole → auxiliary hole → peripheral hole.

6. The diamond wire saw cutting and blasting combined well construction method according to claim 1, characterized in that: In step (4), the depth of the well is 10 to 50 m.

7. The diamond wire saw cutting and blasting combined well construction method according to any one of claims 1 to 6, characterized in that: It is suitable for well completion operations in advanced raise shafts, cutting slot shafts, chute shafts and ventilation shafts.

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