Empty well descending section blasting method
By using the layer-by-layer inward blasting method and setting blastholes in layers, the problems of hole wall damage and debris falling into the well bottom during the empty well lowering process were solved, thus saving the well wall protection and cleaning costs.
Patent Information
- Application Number
- CN202511137127.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-14
- Publication Date
- 2025-10-17
AI Technical Summary
In the existing technology, during the blasting process of the empty well lowering section, the hole wall is easily damaged and debris easily falls into the well bottom, causing blockage and making it difficult to clean.
The method of layer-by-layer inward blasting is adopted. Different types of blast holes are set according to different annular areas, including vertical and horizontal blast holes. The amount of explosives is reduced layer by layer. The height of each layer of layered blasting is 4m, and the total height is 12m.
It reduces the vibration impact of blasting on the well wall, prevents debris from falling to the bottom of the well, avoids the cost of empty well blockage and debris cleaning, and reduces risks.
Smart Images
Figure CN120800115A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the technical field of empty well section reduction blasting, and particularly relates to an empty well section reduction blasting method. BACKGROUND
[0002] In open-pit and underground combined mining, the empty well such as a ventilation shaft on the ground surface needs to be reduced in section with the platform. The ventilation shaft and the like penetrates each section in the underground, and is one of main drainage systems in the underground. Acid mist is heavy in the communication passage of the ventilation shaft and each section in the underground, and equipment is difficult to operate, and it is difficult to clean the broken slag. Therefore, the surface port of the ventilation shaft can only be reduced in section, and it is necessary to ensure that the broken slag cannot fall into the wellbore, and it is necessary to strictly control the blasting vibration.
[0003] The prior art does not clearly perform corresponding section and layer blasting, and in principle, the total charge amount is controlled to perform blasting. The blasting vibration is difficult to control, the hole wall is damaged, the broken slag falls into the well to cause the well to be blocked or falls into the bottom of the well, and it is difficult to clean. SUMMARY
[0004] The application solves the technical problem of providing an empty well section reduction blasting method, avoiding that the hole wall is damaged in the blasting process, and the broken slag falls into the well to cause the well to be blocked or falls into the bottom of the well and is difficult to clean.
[0005] In order to solve the above technical problem, the technical scheme adopted by the application is that:
[0006] An empty well section reduction blasting method comprises the following steps:
[0007] S1: The area outside the 15m periphery of the ventilation shaft well mouth is pre-advanced in place;
[0008] S2: The annular area with a distance of 8-15m from the well mouth of the ventilation shaft well mouth is divided into a plurality of sector areas, a first blast hole in the vertical direction is arranged in each sector area, the plurality of first blast holes are distributed in a circumferential array with the ventilation shaft as the center, the first blast hole is arranged with explosives, and the total charge amount of the annular area with a distance of 8-15m from the well mouth is not more than 300kg; each sector area is sequentially blasted at intervals;
[0009] S3: A second blast hole is transversely arranged on the outer circumferential surface of the annular area with a distance of 3-8m from the well mouth, the horizontal direction depth of the second blast hole is 5m; a plurality of second blast holes are distributed in a circumferential array with the ventilation shaft as the center, the second blast hole is arranged with explosives, and the total charge amount of the annular area with a distance of 3-8m from the well mouth is not more than 48kg;
[0010] S4: arranging third blast holes laterally on the outer circumferential surface of the annular region within a range of 3m around the wellhead, the horizontal depth of the third blast hole being 2m, the interval between two adjacent third blast holes being 1m, and the third blast holes being arranged in a circumferential array with the ventilation shaft as the center, and arranging explosives in the third blast holes, the total explosive amount in the annular region within a range of 3m being not more than 10kg.
[0011] Further, in the above method for descending section blasting of an empty shaft, the total height of the descending section blasting is 12m, and the descending section blasting is performed in three layers, each layer having a height of 4m, and the steps S2-S4 are repeated three times, and in S2, the depth of the first blast hole is 4m.
[0012] Further, in the above method for descending section blasting of an empty shaft, S1 is specifically: blasting an annular region within a range of 60-100m around the ventilation shaft with a total explosive amount of not more than 4t, and the descending section blasting height is 12m.
[0013] Further, in the above method for descending section blasting of an empty shaft, the second blast hole includes an upper row of holes and a lower row of holes arranged vertically, and the lower row of holes is located 1m away from the outer side ground, and the upper row of holes is located 2.5m away from the outer side ground.
[0014] Further, in the above method for descending section blasting of an empty shaft, the upper row of holes is an upward hole obliquely arranged upward, and the angle between the axis of the upward hole and the horizontal plane is 5-9 degrees.
[0015] The beneficial effects of the present application are:
[0016] By means of descending section blasting from the outside to the inside layer by layer and longitudinal layering descending section, different blast hole arrangement structures and specific explosive amounts are selected according to different annular regions, in particular, the annular region of 8-15m is blasted by means of interval blasting in multiple sector regions, this region adopts vertical blast hole arrangement, and the annular region of 3-8m adopts horizontal blast hole arrangement, and by means of decreasing explosive amount from the outside to the inside layer by layer, the vibration influence on the ventilation shaft wall during the descending section blasting can be reduced, the debris generated by the vibration of the ventilation shaft wall can be avoided from falling into the shaft bottom, the phenomenon of empty shaft blockage and the phenomenon of debris falling into the shaft bottom during the descending section blasting of the empty shaft can be avoided, the cost of shafting and debris cleaning can be saved, and the risk caused by the corresponding measures and manual cleaning due to the empty shaft blockage and the debris falling into the shaft bottom can be avoided. BRIEF DESCRIPTION OF DRAWINGS
[0017] Figure 1 It is a top view schematic diagram of the wellhead peripheral region of the method for descending section blasting of an empty shaft according to the embodiment of the present application;
[0018] Figure 2 It is a sectional view schematic diagram of the wellhead peripheral region blasting S1-S2 stage of the method for descending section blasting of an empty shaft according to the embodiment of the present application;
[0019] Figure 3A cross-sectional view of the wellhead peripheral region blasting S2-S3 stage of the empty well step-down blasting method of the embodiment of the present application;
[0020] Figure 4 A cross-sectional view of the wellhead peripheral region blasting S3-S4 stage of the empty well step-down blasting method of the embodiment of the present application;
[0021] Figure 5 A cross-sectional view of the wellhead peripheral region blasting S4 completion stage of the empty well step-down blasting method of the embodiment of the present application;
[0022] Label explanation:
[0023] 1, first blast hole; 2, second blast hole; 21, upper row of holes; 22, lower row of holes; 3, third blast hole; 4, ventilation shaft. DETAILED DESCRIPTION
[0024] To explain the technical content, the purpose and the effect of the present application in detail, the following will be described in conjunction with the embodiments and the accompanying drawings.
[0025] Please refer to Figures 1 to 5 , the embodiment of the present application relates to an empty well step-down blasting method, comprising the following steps:
[0026] Referring to Figure 2 , S1: the area outside the wellhead 15m of the ventilation shaft 4 is pre-advanced in place; that is, the area outside the wellhead 15m is directly blasted and settled 12m, and the annular area within the range of 15m is reserved;
[0027] Referring to Figure 1 and Figure 2 , S2: the annular area within the distance of 8-15m from the wellhead of the ventilation shaft 4 is divided into multiple sector areas, and each sector area is arranged with a vertical first blast hole 1, and the multiple first blast holes 1 are distributed in a circumferential array with the ventilation shaft 4 as the center, the first blast hole 1 is arranged with explosives, and the total explosive quantity of the 8-15m annular area is not more than 300kg; each sector area is blasted one by one with interval;
[0028] In this step, the sector area is blasted one by one with interval, which can reduce the vibration influence on the well wall during blasting and avoid the well wall debris falling into the wellhead; referring to Figure 1 , the 8-15m area is divided into six equally divided sector areas, which are (1)-(6) in turn, and can be blasted one by one in the blasting order of (1)-(3)-(5)-(2)-(4)-(6);
[0029] Referring to Figure 3S3: arranging the second blast hole 2 on the outer circumferential surface of the annular region of 3-8m around the well mouth in a transverse direction, the horizontal depth of the second blast hole 2 is 5m; a plurality of second blast holes 2 are distributed in a circumferential array with the ventilation shaft 4 as the center, the second blast hole 2 is arranged with explosives, and the total explosive amount in the annular region of 3-8m is not more than 48kg;
[0030] After S2, the outer circumferential surface is formed outside the annular region of 3-8m around the well mouth, by arranging the second blast hole 2 on the outer circumferential surface in a transverse direction, compared with the direct vertical direction setting of the blast hole in S1, the vibration influence on the well wall during blasting can be reduced, and the well wall debris falling into the well mouth can be avoided.
[0031] Referring to Figure 4 S4: arranging the third blast hole 3 on the outer circumferential surface of the annular region of 3m around the well mouth in a transverse direction, the horizontal depth of the third blast hole 3 is 2m, the distance between two adjacent third blast holes 3 is 1m, a plurality of third blast holes 3 are distributed in a circumferential array with the ventilation shaft 4 as the center, the third blast hole 3 is arranged with explosives, and the total explosive amount in the annular region of 3m is not more than 10kg.
[0032] The total height of the bench blasting is 12m, which is divided into three layers for bench blasting, and each layer has a height of 4m, the steps of S2-S4 are repeated three times, and in S2, the depth of the first blast hole 1 is 4m.
[0033] Figures 2 to 5 The process schematic diagram of the first layer of blasting bench is shown, and after the third blast hole 3 is completed, the well wall around the ventilation shaft 4 may be relatively thin, which can be replaced by mechanical cutting instead of direct blasting, so that the well wall debris falling into the well can be avoided. The steps of S2-S4 are repeated three times, so that the purpose of reducing the bench by 12m can be achieved.
[0034] In the above embodiments, by means of blasting the bench from the outside to the inside layer by layer, and longitudinal layered benching, different blast hole setting structures and specific explosive amounts are selected according to different annular regions, especially the 8-15m annular region adopts the interval blasting mode of being divided into multiple sector regions, this region adopts the vertical direction blast hole setting, and the 3-8m annular region adopts the transverse blast hole setting, by gradually decreasing the explosive amount from the outside to the inside layer by layer, the vibration influence on the well wall of the ventilation shaft 4 during the blasting benching process can be reduced, and the debris generated by the vibration of the ventilation shaft 4 wall can be avoided from falling into the well bottom, the phenomenon of empty well blocking and the phenomenon of debris falling into the well bottom can be avoided, the cost of well cleaning and debris cleaning can be saved, and the risk caused by the corresponding measures and manual cleaning due to the empty well blocking and the debris falling into the well bottom can be avoided.
[0035] Preferably, S1 specifically comprises: blasting the annular region of 60-100m around the well mouth with a total explosive amount of less than 4t, and the bench blasting height is 12m.
[0036] Referring to Figure 3 Preferably, the second blasthole 2 comprises an upper row of holes 21 and a lower row of holes 22 distributed vertically, the lower row of holes 22 is located 1m away from the outer side ground, and the upper row of holes 21 is located 2.5m away from the outer side ground. The ground refers to the platform formed after the outer layer of the descending section is blasted.
[0037] Preferably, the upper row of holes 21 is an upward hole opened obliquely upward, and the angle between the axis of the upward hole and the horizontal plane is 5-9 degrees. The upper row of holes 21 is provided with a certain inclination angle, which can reduce the impact on the inner side wall during blasting, and further achieve the purpose of avoiding the falling of the wall debris into the well bottom.
[0038] The above is only an embodiment of the present application, and does not limit the patent scope of the present application, and any equivalent transformation or direct or indirect application in the related technical field by using the content of the specification and drawings of the present application is also included in the patent protection scope of the present application.
Claims
1. A method for empty well drop section blasting, characterized in that: The following steps are involved: S1: Advance the area 15m outside the ventilation shaft opening into position in advance; S2: Divide the annular area 8-15 meters from the ventilation shaft mouth into multiple sector-shaped areas. Arrange a vertical first blasthole in each sector-shaped area. The multiple first blastholes are arranged in a circular array with the ventilation shaft as the center. Explosives are placed in the first blastholes. The total amount of explosives in the 8-15 meter annular area does not exceed 300 kg. Blasting is carried out one by one in each sector-shaped area at intervals. S3: Secondary blastholes are arranged transversely on the outer circumference of a 3-8m annular area around the wellhead. The horizontal depth of the second blastholes is 5m. Multiple secondary blastholes are arranged in a circular array centered on the ventilation shaft. Explosives are placed in the second blastholes. The total charge in the 3-8m annular area does not exceed 48kg. S4: A third blasthole is arranged horizontally on the outer circumferential surface of an annular area within 3m around the wellhead. The horizontal depth of the third blasthole is 2m, and the distance between two adjacent third blastholes is 1m. Multiple third blastholes are distributed in a circular array with the ventilation shaft as the center. Explosives are placed in the third blastholes. The total amount of explosives in the annular area within 3m does not exceed 10kg.
2. The empty well drop section blasting method according to claim 1, characterized in that: The total height of the descending blasting is 12m, which is carried out in three layers with a descending blasting height of 4m per layer. The steps S2-S4 are repeated three times. In S2, the depth of the first blast hole is 4m.
3. The empty well drop section blasting method according to claim 2, characterized in that: S1 specifically involves blasting the annular area of 60-100m around the ventilation shaft with a total charge of less than 4t, and the descending blasting height is 12m.
4. The empty well drop section blasting method according to claim 1, characterized in that: The second blastholes include an upper row of holes and a lower row of holes distributed up and down. The lower row of holes is located 1 meter away from the outer ground, and the upper row of holes is located 2.5 meters away from the outer ground.
5. The empty well drop section blasting method according to claim 4, characterized in that: The upper row of holes are upwardly opened obliquely, and the angle between the axis of the upward hole and the horizontal plane is 5-9 degrees.