Multi-section water-gel cartridges for coal mine gas extraction
By connecting threaded pipes to both ends of the charge tube and adopting a tight connection design, the problem of loosening and leakage of multi-section water-gel charge in ultra-long depth and high elevation angle blast holes was solved, realizing the stability of the charge and energy transfer, improving the effect of coal seam pre-splitting and gas extraction, and improving the safety of coal mine production.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- HUAINAN SHUNTAI CHEM
- Filing Date
- 2025-05-22
- Publication Date
- 2026-05-26
AI Technical Summary
Existing multi-section water-gel propellant columns have become loose in ultra-long depth and high-angle blast holes, leading to leakage of the propellant column, which affects coal seam pre-fracturing and gas extraction, and reduces the level of safe production in coal mines.
Threaded tubes are axially integrated at both ends of the charge tube, and the upper and lower plugs are tightly connected through the threaded tubes to enhance the connection strength between the charge particles. A limiting circular plate and a segmented sleeve design are used to ensure sealing and stability. A support cover is used to prevent loosening, and a shallow anti-slip groove is set on the outer peripheral wall to increase friction.
It improves the stability of the explosive charge during the blasting process, reduces the risk of leakage, ensures effective energy transfer and blasting effect, enhances the efficiency of coal seam pre-splitting and gas extraction, and improves the safety level of coal mine production.
Smart Images
Figure CN224285678U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of coal mine gas extraction technology, and specifically relates to a multi-section water-gel explosive column based on coal mine gas extraction. Background Technology
[0002] Deep coal seams in coal mine shafts are buried deep, posing a strong risk of gas outbursts and making gas extraction difficult. Excavation of coal seams in areas with high gas outburst risk is particularly dangerous. In recent years, water-gel explosive charges for coal mine gas extraction have been widely used in deep-hole pre-splitting blasting projects in coal seams both domestically and internationally, achieving good results.
[0003] To accommodate the boreholes drilled for deep-hole blasting in coal seams, multi-section water-gel explosive charges consisting of multiple series-connected explosive charges are typically used. Each explosive charge is a columnar explosive structure formed by loading water-gel explosive into a specific outer shell. Each charge is 1m long and the outer shell is made of flame-retardant, anti-static PVC tubing. The two ends of the tubing are designed with upper and lower plugs, which ensures the sealing of the explosive while facilitating reliable connection between the explosive charges.
[0004] However, in existing explosive charges, the upper and lower plugs are generally sealed to the tube ends using an interference fit, while adjacent explosive charges are connected by screws to their respective upper and lower plugs. This results in the shells of adjacent explosive charges not being tightly connected. When encountering extremely long and deep boreholes with large elevation angles, the explosive charge at the end of a multi-section water-gel explosive charge has to bear the weight of most of the subsequent explosive charges. Their connections are prone to loosening, leading to leakage of the liquid phase components of the water-gel explosive, or even detachment, affecting the detonation effect of the entire water-gel explosive charge. This, in turn, affects deep-hole pre-fracturing and gas extraction in coal seams, reducing the safety level of coal mine production. Utility Model Content
[0005] This utility model addresses the shortcomings of existing technologies by providing a multi-section water-gel explosive charge for coal mine gas extraction. The specific technical solution is as follows:
[0006] This utility model provides a multi-section water-gel propellant column for coal mine gas extraction, which is composed of multiple propellant columns connected in series.
[0007] The drug cartridge includes a drug-filled cylindrical tube, both ends of which are integrally connected to threaded tubes axially, and the outer diameter of the threaded tubes is smaller than the outer diameter of the drug-filled cylindrical tube; one of the threaded tubes is screwed with an upper plug, and the other threaded tube is inserted with a lower plug.
[0008] When two adjacent drug cartridges are connected in series, the upper plug of one drug cartridge is screwed into a threaded pipe in the other drug cartridge that has a lower plug already inserted.
[0009] As a preferred technical solution of this utility model, the lower plug includes a second plug with a cylindrical structure. One end of the second plug is axially integrated with a limiting circular plate. The second plug is interference-fitted with the corresponding threaded pipe and sealed. The outer diameter of the limiting circular plate is the same as the outer diameter of the threaded pipe.
[0010] As a preferred embodiment of this utility model, the upper plug includes a sleeve, which is divided into an upper chamber and a lower chamber by a partition integrally sealed in the middle of its inner part. The inner peripheral wall of the lower chamber is screwed into the outer peripheral wall of the corresponding threaded tube, and a cylindrical plug block is integrally connected to the top wall of the lower chamber. The plug block is gap-sealed into the corresponding threaded tube. The upper chamber is screwed into the threaded tube of the adjacent drug pellet, which has a lower plug already inserted.
[0011] In a preferred embodiment of this invention, the outer diameter of the sleeve is the same as the outer diameter of the charge tube.
[0012] As a preferred technical solution of this utility model, the outer end face of the limiting circular plate is provided with a square groove in the axial direction, and a handle is vertically arranged in the middle of the square groove. The handle is provided with grooves on both sides.
[0013] As a preferred technical solution of this utility model, the outer peripheral wall of the drug-loading tube is provided with multiple sets of anti-slip shallow grooves of arc-shaped structure at equal intervals along the axis.
[0014] As a preferred technical solution of this utility model, a circular cover is provided at the end of the multi-section water-based adhesive cartridge. The cover is screwed into a threaded tube with a lower plug already inserted in the cartridge body, and a lead hole is radially opened on one side of the bottom of the cover.
[0015] In a preferred embodiment of this invention, the outer diameter of the cover is the same as the outer diameter of the loading tube.
[0016] The beneficial effects of this utility model are:
[0017] This invention relates to a multi-section water-gel propellant charge. It integrates threaded tubes axially at both ends of the propellant tube, with one threaded tube sealed with a plug and the other with a lower plug. When two adjacent propellant charges are connected in series, the upper plug of one charge is directly screwed into the threaded tube of the other. This design significantly enhances the connection strength between the propellant tubes in adjacent charges, effectively resisting the weight of the following charge and preventing loosening or detachment in ultra-long depth and high-angle boreholes. This tight connection ensures the stability of the propellant charge during blasting and reduces the risk of leakage due to loose connections. Attached Figure Description
[0018] Figure 1 A schematic diagram of the multi-section water-based adhesive cartridge structure of this utility model is shown;
[0019] Figure 2 A schematic diagram of the connection structure of the Chinese medicine column of this utility model is shown;
[0020] Figure 3 A schematic diagram of the exploded structure of the Chinese medicine column of this utility model is shown;
[0021] Figure 4 A schematic diagram (I) of the upper plug structure in this utility model is shown;
[0022] Figure 5 A schematic diagram (II) of the structure of the upper plug in this utility model is shown;
[0023] Figure 6 A cross-sectional view of the upper plug in this utility model is shown;
[0024] Figure 7 A schematic diagram of the lower plug structure of this utility model is shown;
[0025] Figure 8 This invention provides a schematic diagram of the structure of the herbal medicine column assembly cover.
[0026] Figure 9 A schematic diagram of the cover structure in this utility model is shown.
[0027] The figure shows: 1. Propellant cartridge; 11. Propellant loading tube; 111. Threaded tube; 112. Anti-slip shallow groove; 12. Upper plug; 121. Sleeve; 122. Partition plate; 123. Plug one; 13. Lower plug; 131. Plug two; 132. Limiting round plate; 133. Square groove; 134. Pull handle; 135. Groove; 2. Support cover; 21. Lead hole. Detailed Implementation
[0028] To make the objectives, technical solutions, and advantages of this utility model clearer, the following detailed description is provided in conjunction with embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this utility model.
[0029] Example 1
[0030] To address the technical problems in the background section, the following multi-section water-gel explosive charge based on coal mine gas extraction is proposed:
[0031] Combination Figures 1-3 As shown, a multi-section water-gel propellant column based on coal mine gas extraction is composed of multiple propellant columns 1 connected in series.
[0032] The drug cartridge 1 includes a drug-filling circular tube 11, with threaded tubes 111 integrally connected to both ends of the drug-filling circular tube 11 axially, and the outer diameter of the threaded tubes 111 is smaller than the outer diameter of the drug-filling circular tube 11; one of the threaded tubes 111 is screwed with an upper plug 12, and the other threaded tube 111 is inserted with a lower plug 13.
[0033] When two adjacent drug cartridges 1 are connected in series, the upper plug 12 of one drug cartridge 1 is screwed into the threaded tube 111 of the other drug cartridge 1, which has a lower plug 13 already inserted and sealed.
[0034] By adopting the above technical solution, the multi-section water-gel propellant charge integrates threaded tubes 111 axially at both ends of the propellant tube 11, and screws a plug 12 onto one of the threaded tubes and inserts a lower plug 13 onto the other threaded tube. When two adjacent propellant charges 1 are connected in series, the upper plug 12 of one propellant charge 1 is directly screwed onto the threaded tube 111 of the other propellant charge 1. This design significantly enhances the connection strength between the propellant tubes 11 in adjacent propellant charges 1, and can more effectively resist the self-weight of the propellant charge behind it, preventing loosening or falling off in ultra-long depth and high elevation boreholes. This tight connection method ensures the stability of the propellant charge 1 during the blasting process and reduces the risk of leakage due to loose connection.
[0035] Because the connections between the explosive charges 1 are tight and stable, the shock wave and energy generated during the explosion can be transferred more effectively between the explosive charges 1, reducing energy loss caused by loose connections or leakage. This efficient energy transfer ensures the uniformity and reliability of blasting, which helps to realize deep hole pre-fracturing of coal seams and gas extraction, and improves the safety production level of coal mines.
[0036] Example 2
[0037] Combination Figures 2-8 As shown, based on the above embodiments, this embodiment further provides the following:
[0038] In this embodiment, as Figure 2 , Figure 3 and Figure 7 As shown, the lower plug 13 includes a cylindrical plug block 131. One end of the plug block 131 is axially integrated with a limiting circular plate 132. The plug block 131 is press-fitted into the corresponding threaded pipe 111, and the outer diameter of the limiting circular plate 132 is the same as the outer diameter of the threaded pipe 111.
[0039] By adopting the above technical solution, the interference fit between the plug block 131 in the lower plug 13 and the threaded tube 111, as well as the design of the limiting circular plate 132, can not only ensure the sealing of the connection between the lower plug 13 and the drug-filling circular tube 11, but also ensure that the outer diameter of the limiting circular plate 132 is the same as the outer diameter of the threaded tube 111, and will not affect the subsequent screw connection with the upper plug 12 of the adjacent drug column 1.
[0040] like Figures 2-6 As shown, the upper plug 12 includes a sleeve 121, which is divided into an upper chamber and a lower chamber by a partition 122 axially and integrally sealed in the middle of its inner part. The inner peripheral wall of the lower chamber is screwed to the outer peripheral wall of the corresponding threaded tube 111, and a cylindrical plug block 123 is axially and integrally connected to the top wall of the lower chamber. The plug block 123 is gap-locked and sealed to the corresponding threaded tube 111. The upper chamber is screwed to the threaded tube 111 of the adjacent drug pellet 1, which has a lower plug 13 already inserted and sealed.
[0041] By adopting the above technical solution, the upper plug 12 divides the sleeve 121 into an upper chamber and a lower chamber through the partition 122. The inner peripheral wall of the lower chamber is screwed into the threaded tube 111, and the upper chamber is screwed into the threaded tube 111 of the adjacent propellant column 1, which has the lower plug 13 already inserted and sealed. In this way, the propellant loading tubes 11 of the two adjacent propellant columns 1 can be directly connected by a large-area, tight threaded connection, which can prevent loosening or falling off in ultra-long depth and high elevation angle boreholes.
[0042] Meanwhile, the lower chamber of the inner peripheral wall of the sleeve 121 in the upper plug 12 is screwed into the threaded pipe 111, while the plug block 123 is interlocked with the threaded pipe 111. This double sealing design ensures a tight connection and high sealing between the upper plug 12 and the charge tube 11.
[0043] like Figure 2 and Figure 8 As shown, the outer diameter of the sleeve 121 is the same as the outer diameter of the charge tube 11.
[0044] By adopting the above technical solution, the outer diameter of the sleeve 121 is designed to be the same as the outer diameter of the charge tube 11, which enables the entire multi-section water-gel charge to fit tightly with the inner wall of the drilled borehole, thereby improving the blasting effect.
[0045] like Figure 7 As shown, a square groove 133 is axially formed on the outer end face of the limiting circular plate 132, and a handle 134 is vertically arranged in the middle of the square groove 133. Grooves 135 are symmetrically formed on both sides of the handle 134.
[0046] By adopting the above technical solution, the square groove 133 and the handle 134 can facilitate the insertion and removal of the lower plug 13 and the charge tube 11; the groove 135 on the side of the handle 134 can increase the friction force when the user's fingers grip and insert / remove the plug.
[0047] like Figure 3 and Figure 8 As shown, the outer circumferential wall of the drug-loading tube 11 is provided with multiple sets of arc-shaped anti-slip shallow grooves 112 at equal intervals along the axial direction.
[0048] By adopting the above technical solution, the anti-slip shallow groove 112 can increase the friction between the outer wall of the charge tube 11 and the inner wall of the borehole, which can effectively prevent the entire multi-section water-gel charge from slipping in the borehole at a high elevation angle.
[0049] Example 3
[0050] Combination Figure 8 and Figure 9 As shown, based on the above embodiments, this embodiment further provides the following:
[0051] In this embodiment, as Figure 8 and Figure 9 As shown, a circular cover 2 is fitted at the end of the multi-section water-based adhesive cartridge. The cover 2 is screwed into the threaded tube 111 in the corresponding cartridge body 1, which has a lower plug 13 already inserted and sealed. A lead hole 21 is radially opened on one side of the bottom of the cover 2.
[0052] By adopting the above technical solution, the cover 2 can prevent the liquid phase components of the water-gel explosive from leaking out due to the loosening of the lower plug 13 of the explosive body 1 at the end of the multi-section water-gel explosive.
[0053] In addition, a special detonator is inserted into the propellant body 1 at the end of the multi-section water-based propellant column, and the lead wire hole 21 at the bottom of the cover 2 allows the lead wire of the detonator to be led out from the bottom of the propellant tube 11 and then pass through the lead wire hole 21 to connect with the external detonation device.
[0054] like Figure 8 As shown, the outer diameter of the cover 2 is the same as the outer diameter of the drug-loading tube 11.
[0055] By adopting the above technical solution, the outer diameter of the cover 2 is designed to be the same as the outer diameter of the charge tube 11, so that the entire multi-section water-gel charge can fit tightly with the inner wall of the drilled borehole, thereby improving the blasting effect.
[0056] Working principle and usage process of this utility model:
[0057] When using this utility model, firstly, according to actual needs, prepare several sections of explosive cylinder 1. Each section of explosive cylinder 1 is filled with appropriate water-gel explosive. One end of the threaded tube 111 of the explosive cylinder 11 is screwed with an upper plug 12, and the other end is inserted with a lower plug 13. The lower plug 13 is sealed by an interference fit between the plug block 2 131 and the corresponding threaded tube 111.
[0058] During assembly, the upper plug 12 of one propellant cartridge 1 is screwed tightly to the threaded tube 111 of another propellant cartridge 1 with the lower plug 13 already inserted, and this process is repeated until the required length is reached. The upper plug 12's sleeve 121 is divided into an upper chamber and a lower chamber by a partition 122. The lower chamber is screwed to the threaded tube 111 of the corresponding propellant cartridge 1, and the upper chamber is connected to the threaded tube 111 of the adjacent propellant cartridge 1 with the lower plug 13 already inserted, forming an integrated series structure.
[0059] After assembly, the circular cover 2 is screwed onto the lower plug 13 of the tail end of the explosive charge 1. The lead wire hole 21 at the bottom of the cover 2 is used to install and lead out the lead wire of the detonator. In use, the assembled multi-section water-gel explosive charge is placed in the designated borehole in the coal mine and detonated through the lead wire.
[0060] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.
Claims
1. A multi-section water-gel propellant column for coal mine gas extraction, the multi-section water-gel propellant column being composed of multiple propellant columns (1) connected in series, characterized in that: The drug cartridge (1) includes a drug-filling circular tube (11), both ends of which are axially and integrally connected with threaded tubes (111), and the outer diameter of the threaded tubes (111) is smaller than the outer diameter of the drug-filling circular tube (11); one of the threaded tubes (111) is screwed with an upper plug (12), and the other threaded tube (111) is inserted with a lower plug (13); When two adjacent drug cartridges (1) are connected in series, the upper plug (12) of one drug cartridge (1) is screwed into the threaded tube (111) of the other drug cartridge (1) which has a lower plug (13) already inserted.
2. The multi-section water-gel explosive column based on coal mine gas extraction according to claim 1, characterized in that: The lower plug (13) includes a cylindrical plug block two (131), one end of which is axially integrated with a limiting circular plate (132). The plug block two (131) is press-fitted into the corresponding threaded pipe (111), and the outer diameter of the limiting circular plate (132) is the same as the outer diameter of the threaded pipe (111).
3. The multi-section water-gel explosive column based on coal mine gas extraction according to claim 2, characterized in that: The upper plug (12) includes a sleeve (121), which is divided into an upper chamber and a lower chamber by a partition (122) axially and integrally sealed in the middle of its inner part. The inner peripheral wall of the lower chamber is screwed into the outer peripheral wall of the corresponding threaded tube (111), and a cylindrical plug block (123) is axially and integrally connected to the top wall of the lower chamber. The plug block (123) is gap-locked into the corresponding threaded tube (111). The upper chamber is screwed into the threaded tube (111) of the adjacent drug cartridge (1) which has a lower plug (13) already inserted.
4. The multi-section water-gel explosive column based on coal mine gas extraction according to claim 3, characterized in that: The outer diameter of the sleeve (121) is the same as the outer diameter of the charge tube (11).
5. The multi-section water-gel explosive column based on coal mine gas extraction according to claim 2, characterized in that: The outer end face of the limiting circular plate (132) is provided with a square groove (133) axially, and a handle (134) is vertically arranged in the middle of the square groove (133). The handle (134) is provided with grooves (135) symmetrically on both sides.
6. The multi-section water-gel explosive column based on coal mine gas extraction according to claim 1, characterized in that: The outer circumferential wall of the drug-loading tube (11) is provided with multiple sets of anti-slip shallow grooves (112) with equal spacing in the axial direction.
7. The multi-section water-gel explosive column based on coal mine gas extraction according to claim 2, characterized in that: The multi-section water-based gel cartridge is fitted with a circular cover (2) at its end. The cover (2) is screwed into a threaded tube (111) with a lower plug (13) already inserted in the cartridge body (1). A lead hole (21) is radially opened on one side of the bottom of the cover (2).
8. The multi-section water-gel explosive column based on coal mine gas extraction according to claim 7, characterized in that: The outer diameter of the cover (2) is the same as the outer diameter of the drug-filling tube (11).