CN204060615U - Mine fracturing drilling and sealing device - Google Patents
Mine fracturing drilling and sealing device Download PDFInfo
- Publication number
- CN204060615U CN204060615U CN201420542026.4U CN201420542026U CN204060615U CN 204060615 U CN204060615 U CN 204060615U CN 201420542026 U CN201420542026 U CN 201420542026U CN 204060615 U CN204060615 U CN 204060615U
- Authority
- CN
- China
- Prior art keywords
- casing
- steel pipe
- water
- sealing device
- injection steel
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Abstract
The utility model discloses a kind of mine fracturing drilling and sealing device, comprise casing and penetrate the water-injection steel pipe in casing, it is outer and insert in boring that casing is stretched out in one end of water-injection steel pipe, the other end of water-injection steel pipe is by being symmetrical arranged and being semicircular upper casing lid and lower casing lid blocks and passes outside upper casing lid and lower casing lid, upper casing lid is all fixedly connected with casing with lower casing lid, upper casing covers and is provided with exhaust opening, exhaust opening arranges exhaust gate valve, lower casing covers and is provided with grouting port, grouting port is arranged slip casting gate valve, be positioned at casing and external diameter is greater than the cylindrical cloth bag of casing internal diameter after be set with bulging on one section of water-injection steel pipe of boring, the two ends of cylindrical cloth bag are all fixedly connected with water-injection steel pipe, cylindrical cloth bag is built with polyurethane material, cylindrical cloth bag is provided with the zipper opening loaded for polyurethane material.The utility model uses easy to operate, and realize cost low, sealing of hole speed is fast, effective, can realize the borehole sealing of arbitrary angle.
Description
Technical field
The utility model belongs to coal bed gas extraction technical field, is specifically related to a kind of mine fracturing drilling and sealing device.
Background technology
Along with the increase of the pit mining degree of depth, geostatic stress constantly increases, and coal-bed gas pressure and gas bearing capacity strengthen year by year, and some mines become highly gassy mine or coal and gas outburst mine from low gaseous mine.Safety of Coal Mine Production condition worsens further, Gas Disaster serious threat China major part mining area, is the significant problem needing to solve.Coal seam gas-bearing capacity increases and gas permeability of coal seam is deteriorated, and causes gas pumping difficulty to strengthen, and gas pumping radius reduces, and has a strong impact on extracting result.Fracturing is the anti-reflection effective way in coal seam, is the strong guarantee improving the extraction of Gas pre-drainage concentration.Hydraulic fracturing anti-reflection technology is exactly to coal seam press-in water under high pressure by boring, when the speed that hydraulic pressure enters far exceedes the natural water absorbing capacity in coal seam, because flow resistance increases, the fluid pressure entering coal seam rises gradually, when exceeding the rock pressure above coal seam, closed crack original in coal seam will be pressed off forms new distribution network, and coal seam permeability will increase, thus improve gas pumping effect, ensure the safety in production in colliery.
For underground coal mine hydraulic fracturing technology, an important technical barrier is exactly the high pressure sealing problem of boring, and the quality of sealing of hole is directly connected to the success or not of fracturing.At present, the underground coal mine fracturing encapsulating method mainly taked of holing has the inorganic material such as cement mortar, hole packer sealing of hole, cement mortar sealing of hole can not invade minute fissure completely due to cement mortar, by naturally sinking to solidifying, easily cause coal bed gas extraction later stage sealing material to be separated with coal seam, drainage occurs when causing water filling and causes sealing of hole failure; The inorganic material sealing of holes such as hole packer are easily by high pressure disruption, and sealing of hole success rate is low, and material price is high, cause sealing cost high.
Utility model content
Technical problem to be solved in the utility model is for above-mentioned deficiency of the prior art, a kind of mine fracturing drilling and sealing device is provided, its structure is simple, use easy to operate, realize cost low, sealing of hole speed is fast, and sealing of hole is effective, the borehole sealing of arbitrary angle can be realized, practical.
For solving the problems of the technologies described above, the technical solution adopted in the utility model is: a kind of mine fracturing drilling and sealing device, it is characterized in that: comprise casing and penetrate the water-injection steel pipe in casing, it is outer and insert in boring that casing is stretched out in one end of described water-injection steel pipe, the other end of described water-injection steel pipe is by being symmetrical arranged and being semicircular upper casing lid and lower casing lid blocks and passes outside upper casing lid and lower casing lid, described upper casing lid is all fixedly connected with casing with lower casing lid, described upper casing covers and is provided with exhaust opening, described exhaust opening arranges exhaust gate valve, described lower casing covers and is provided with grouting port, described grouting port is arranged slip casting gate valve, be positioned at casing and external diameter is greater than the cylindrical cloth bag of casing internal diameter after be set with bulging on one section of water-injection steel pipe of boring, the two ends of described cylindrical cloth bag are all fixedly connected with water-injection steel pipe, described cylindrical cloth bag is built with polyurethane material, described cylindrical cloth bag is provided with the zipper opening loaded for polyurethane material.
Above-mentioned mine fracturing drilling and sealing device, is characterized in that: the level that is fitted with in described exhaust opening stretches into the stack in casing, the inwall of described casing is arranged at intervals with two for lifting the suspension ring of stack.
Above-mentioned mine fracturing drilling and sealing device, is characterized in that: the stack length stretched in casing is the length of water-injection steel pipe in casing
Above-mentioned mine fracturing drilling and sealing device, is characterized in that: the two ends of described cylindrical cloth bag are all fixedly connected with water-injection steel pipe by steel wire.
Above-mentioned mine fracturing drilling and sealing device, is characterized in that: the steel pile casting of described casing to be wall thickness be 10mm ~ 15mm, the length of described casing is 36m ~ 38m, the internal diameter 0.2m ~ 0.4m larger than the internal diameter of boring of described casing.
Above-mentioned mine fracturing drilling and sealing device, is characterized in that: the length of described water-injection steel pipe is 42m ~ 44m, and the external diameter of described water-injection steel pipe is 4cm ~ 6cm, and the length passing one section of water-injection steel pipe outside casing lid and lower casing lid is 2m ~ 4m.
Above-mentioned mine fracturing drilling and sealing device, is characterized in that: the length of described cylindrical cloth bag is 2m ~ 4m.
Above-mentioned mine fracturing drilling and sealing device, is characterized in that: described upper casing lid is fixedly connected with casing by the first bolt, and described lower casing lid is fixedly connected with casing by the second bolt.
Above-mentioned mine fracturing drilling and sealing device, is characterized in that: the shape of described exhaust opening is tubular, and the length of described exhaust opening is 0.5m ~ 1.5m, and the internal diameter of described exhaust opening is 1.5cm ~ 2.5cm.
Above-mentioned mine fracturing drilling and sealing device, is characterized in that: the shape of described grouting port is tubular, and the length of described grouting port is 1m ~ 2m, and the internal diameter of described grouting port is 2cm ~ 4cm.
The utility model compared with prior art has the following advantages:
1, the utility model structure is simple, and processing and fabricating is convenient, uses easy to operate.
2, adopt the utility model to carry out sealing of hole, drilling front end adopts the polyurethane material shutoff of cylindrical cloth bag and inside thereof, and remainder is casing structure, significantly can reduce the use of polyurethane material; Casing can protect drilling orifice, prevents collapse hole, prevents the sediment in boring procedure from refluxing, and casing can reduce the gas permeability of sealing of hole section surrounding medium simultaneously, reduces the gas leakage of boring, thus realizes the sealing of mine fracturing boring.
3, exhaust ports of the present utility model can the stack of grafting certain length as required, exhaust opening does not run in tracheae time, the utility model be applicable to boring direction obliquely from the horizontal by certain angle or boring direction be the operating mode of horizontal direction, when stretching into the stack in casing when the level that is fitted with in exhaust opening, the utility model is applicable to boring direction obliquely from the horizontal by the operating mode of certain angle, the novel bored grouting sealing of hole that can realize arbitrary angle of this use, injecting paste material blocking exhaust opening in slip casting process can be avoided, injecting paste material can be made evenly to be full of whole space, realize the sealing of coal seam hydraulic fracture boring.
4, of the present utility model to realize cost low, and sealing of hole speed is fast, and sealing of hole is effective, practical, is convenient to promote the use of.
In sum, the utility model structure is simple, uses easy to operate, realizes cost low, and sealing of hole speed is fast, and sealing of hole is effective, can realize the borehole sealing of arbitrary angle, practical.
Below by drawings and Examples, the technical solution of the utility model is described in further detail.
Accompanying drawing explanation
Fig. 1 is the structural representation of the utility model embodiment 1.
Fig. 2 is the right view of Fig. 1.
Fig. 3 is the structural representation of the utility model embodiment 2.
Fig. 4 is the right view of Fig. 3.
Description of reference numerals:
1-boring; 2-cylindrical cloth bag; 3-water-injection steel pipe;
4-casing; 5-1-upper casing lid; 5-2-lower casing lid;
6-exhaust opening; 7-grouting port; 8-1-the first bolt;
8-2-the second bolt; 9-steel wire; 10-stack;
11-suspension ring; 12-polyurethane material.
Detailed description of the invention
Embodiment 1
As depicted in figs. 1 and 2, the water-injection steel pipe 3 that the utility model comprises casing 4 and penetrates in casing 4, it is outer and insert in boring 1 that casing 4 is stretched out in one end of described water-injection steel pipe 3, the other end of described water-injection steel pipe 3 blocks by being symmetrical arranged and being semicircular upper casing lid 5-1 and lower casing lid 5-2 and passes outside upper casing lid 5-1 and lower casing lid 5-2, described upper casing lid 5-1 is all fixedly connected with casing 4 with lower casing lid 5-2, described upper casing lid 5-1 is provided with exhaust opening 6, described exhaust opening 6 arranges exhaust gate valve, described lower casing lid 5-2 is provided with grouting port 7, described grouting port 7 arranges slip casting gate valve, be positioned at casing 4 and external diameter is greater than the cylindrical cloth bag 2 of casing 4 internal diameter after be set with bulging on one section of water-injection steel pipe 3 of boring 1, the two ends of described cylindrical cloth bag 2 are all fixedly connected with water-injection steel pipe 3, described cylindrical cloth bag 2 is built with polyurethane material 12, described cylindrical cloth bag 2 is provided with the zipper opening loaded for polyurethane material 12.
As shown in Figure 1, in the present embodiment, the two ends of described cylindrical cloth bag 2 are all fixedly connected with water-injection steel pipe 3 by steel wire 9.
As shown in Figure 1, in the present embodiment, described casing 4 for wall thickness be the steel pile casting of 10mm ~ 15mm, the length of described casing 4 is 36m ~ 38m, the internal diameter 0.2m ~ 0.4m larger than the internal diameter of boring 1 of described casing 4.Preferably, the wall thickness of described casing 4 is 12mm, and the length of described casing 4 is 37m, the internal diameter 0.3m larger than the internal diameter of boring 1 of described casing 4.
As shown in Figure 1, in the present embodiment, the length of described water-injection steel pipe 3 is 42m ~ 44m, and the external diameter of described water-injection steel pipe 3 is 4cm ~ 6cm, and the length passing one section of water-injection steel pipe 3 outside casing lid 5-1 and lower casing lid 5-2 is 2m ~ 4m.Preferably, the length of described water-injection steel pipe 3 is 43m, and the external diameter of described water-injection steel pipe 3 is 5cm, and the length passing one section of water-injection steel pipe 3 outside casing lid 5-1 and lower casing lid 5-2 is 3m.
As shown in Figure 1, in the present embodiment, the length of described cylindrical cloth bag 2 is 2m ~ 4m.Preferably, the length of described cylindrical cloth bag 2 is 3m.
As depicted in figs. 1 and 2, in the present embodiment, described upper casing lid 5-1 is fixedly connected with casing 4 by the first bolt 8-1, and described lower casing lid 5-2 is fixedly connected with casing 4 by the second bolt 8-2.
As depicted in figs. 1 and 2, in the present embodiment, the shape of described exhaust opening 6 is tubular, and the length of described exhaust opening 6 is 0.5m ~ 1.5m, and the internal diameter of described exhaust opening 6 is 1.5cm ~ 2.5cm.Preferably, the length of described exhaust opening 6 is 1m, and the internal diameter of described exhaust opening 6 is 2cm.
As depicted in figs. 1 and 2, in the present embodiment, the shape of described grouting port 7 is tubular, and the length of described grouting port 7 is 1m ~ 2m, and the internal diameter of described grouting port 7 is 2cm ~ 4cm.Preferably, the length of described grouting port 7 is 1.5m, and the internal diameter of described grouting port 7 is 3cm.
In the present embodiment, exhaust opening 6 does not run in tracheae 10, hole sealing device in the present embodiment is the operating mode of horizontal direction from the horizontal by certain angle or boring 1 direction for 1 direction of holing obliquely, and the detailed process adopting the hole sealing device in the present embodiment to carry out mine fracturing drilling and sealing comprises the following steps:
(1) in the boring 1 of mine fracturing, get out that internal diameter matches with the external diameter of casing 4, the hole sealing device installing hole of length 40cm ~ 60cm less of the length of casing 4;
(2) be placed in by casing 4 in described hole sealing device installing hole, the aperture 40cm ~ 60cm of described hole sealing device installing hole is stretched out in one end of casing 4, the gap clay backfilling compacting between casing 4 outer wall and described hole sealing device installing hole inwall;
(3) first cylindrical cloth bag 2 is sleeved on water-injection steel pipe 3, then the two ends of cylindrical cloth bag 2 are all fixedly connected on water-injection steel pipe 3 by steel wire 9, then the slide fastener of the zipper opening in cylindrical cloth bag 2 is opened, polyurethane material 12 is loaded rapidly in cylindrical cloth bag 2 equably, strain the slide fastener of the zipper opening in cylindrical cloth bag 2 again, the entirety of cylindrical cloth bag 2 and water-injection steel pipe 3 is quickly passed through casing 4, and make cylindrical cloth bag 2 withstand on the intersection of boring 1 and described hole sealing device installing hole, polyurethane material 12 meeting rapid expanding in cylindrical cloth bag 2 forms the shutoff between boring 1 and casing 4 top,
(4) the first bolt 8-1 is adopted to be fixedly connected on casing 4 by upper casing lid 5-1, and adopting the second bolt 8-2 to be fixedly connected on casing 4 by lower casing lid 5-2, water-injection steel pipe 3 is blocked by upper casing lid 5-1 and lower casing lid 5-2 and passes outside upper casing lid 5-1 and lower casing lid 5-2;
(5) by grouting port 7 to slip casting in the gap between section drainage tube 4 outer wall of between cylindrical cloth bag 2 and casing lid 5 and casing 4 inwall, stop slip casting when slurry phenomenon appears returning in exhaust opening 6, and close described slip casting gate valve and described exhaust gate valve;
(6) water-injection steel pipe 3 is connected with the high pressure pumping station of fracturing, carries out coal seam hydraulic fracture.
Embodiment 2
As shown in Figure 3 and Figure 4, the present embodiment as different from Example 1: the level that is fitted with in described exhaust opening 6 stretches into the stack 10 in casing 4, the inwall of described casing 4 is arranged at intervals with two for lifting the suspension ring 11 of stack 10.Stack 10 length stretched in casing 4 is the length of water-injection steel pipe 3 in casing 4
all the other structures are all identical with embodiment 1.
In the present embodiment, the level that is fitted with in exhaust opening 6 stretches into the stack 10 in casing 4, hole sealing device in the present embodiment is for holing 1 direction obliquely from the horizontal by the operating mode of certain angle, when arranging stack 10 for preventing slip casting, steam vent is blocked, the hole sealing device in the present embodiment is adopted to carry out the detailed process of mine fracturing drilling and sealing as different from Example 1: also to need to insert stack 10 after step (4) on exhaust opening 6, stack 10 to stretch in casing 4 and inserts in suspension ring 11, is fixed by suspension ring 11.All the other steps are all identical with embodiment 1.
The above; it is only preferred embodiment of the present utility model; not the utility model is imposed any restrictions; every above embodiment is done according to the utility model technical spirit any simple modification, change and equivalent structure change, all still belong in the protection domain of technical solutions of the utility model.
Claims (10)
1. a mine fracturing drilling and sealing device, it is characterized in that: comprise casing (4) and penetrate the water-injection steel pipe (3) in casing (4), casing (4) is stretched out and insert in boring (1) outward in one end of described water-injection steel pipe (3), the other end of described water-injection steel pipe (3) blocks by being symmetrical arranged and being semicircular upper casing lid (5-1) and lower casing lid (5-2) and passes upper casing lid (5-1) and lower casing lid (5-2) outward, described upper casing lid (5-1) is all fixedly connected with casing (4) with lower casing lid (5-2), described upper casing lid (5-1) is provided with exhaust opening (6), (6) arrange exhaust gate valve to described exhaust opening, described lower casing lid (5-2) is provided with grouting port (7), (7) arrange slip casting gate valve to described grouting port, be positioned at casing (4) and external diameter is greater than the cylindrical cloth bag (2) of casing (4) internal diameter after be set with bulging on one section of water-injection steel pipe (3) of boring (1), the two ends of described cylindrical cloth bag (2) are all fixedly connected with water-injection steel pipe (3), described cylindrical cloth bag (2) is built with polyurethane material (12), described cylindrical cloth bag (2) is provided with the zipper opening loaded for polyurethane material (12).
2. according to mine fracturing drilling and sealing device according to claim 1, it is characterized in that: the level that is fitted with in described exhaust opening (6) stretches into the stack (10) in casing (4), the inwall of described casing (4) being arranged at intervals with two for lifting the suspension ring (11) of stack (10).
3. according to mine fracturing drilling and sealing device according to claim 2, it is characterized in that: stack (10) length stretched in casing (4) is the length of water-injection steel pipe (3) in casing (4)
4. according to mine fracturing drilling and sealing device according to claim 1, it is characterized in that: the two ends of described cylindrical cloth bag (2) are all fixedly connected with water-injection steel pipe (3) by steel wire (9).
5. according to mine fracturing drilling and sealing device according to claim 1, it is characterized in that: described casing (4) for wall thickness be the steel pile casting of 10mm ~ 15mm, the length of described casing (4) is 36m ~ 38m, the internal diameter 0.2m ~ 0.4m larger than the internal diameter of boring (1) of described casing (4).
6. according to mine fracturing drilling and sealing device according to claim 1, it is characterized in that: the length of described water-injection steel pipe (3) is 42m ~ 44m, the external diameter of described water-injection steel pipe (3) is 4cm ~ 6cm, and the length passing casing lid (5-1) and lower casing lid (5-2) one section of water-injection steel pipe (3) is outward 2m ~ 4m.
7. according to mine fracturing drilling and sealing device according to claim 1, it is characterized in that: the length of described cylindrical cloth bag (2) is 2m ~ 4m.
8. according to mine fracturing drilling and sealing device according to claim 1, it is characterized in that: described upper casing lid (5-1) is fixedly connected with casing (4) by the first bolt (8-1), described lower casing lid (5-2) is fixedly connected with casing (4) by the second bolt (8-2).
9. according to mine fracturing drilling and sealing device according to claim 1, it is characterized in that: the shape of described exhaust opening (6) is tubular, the length of described exhaust opening (6) is 0.5m ~ 1.5m, and the internal diameter of described exhaust opening (6) is 1.5cm ~ 2.5cm.
10. according to mine fracturing drilling and sealing device according to claim 1, it is characterized in that: the shape of described grouting port (7) is tubular, the length of described grouting port (7) is 1m ~ 2m, and the internal diameter of described grouting port (7) is 2cm ~ 4cm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420542026.4U CN204060615U (en) | 2014-09-19 | 2014-09-19 | Mine fracturing drilling and sealing device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420542026.4U CN204060615U (en) | 2014-09-19 | 2014-09-19 | Mine fracturing drilling and sealing device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN204060615U true CN204060615U (en) | 2014-12-31 |
Family
ID=52202153
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201420542026.4U Expired - Fee Related CN204060615U (en) | 2014-09-19 | 2014-09-19 | Mine fracturing drilling and sealing device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN204060615U (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104653150A (en) * | 2015-02-04 | 2015-05-27 | 成都科创佳思科技有限公司 | Plugging device |
| CN105507940A (en) * | 2016-01-11 | 2016-04-20 | 山东科技大学 | Slotting, plugging and fracturing integrated type intensified marsh gas extraction device and method |
| CN110513100A (en) * | 2019-09-11 | 2019-11-29 | 华北科技学院 | A kind of field experiment method improving gas pressure measurement success rate |
| CN112855071A (en) * | 2021-02-04 | 2021-05-28 | 河南理工大学 | Device and method for plugging gas extraction drill hole by using microbial mineralization circulation |
-
2014
- 2014-09-19 CN CN201420542026.4U patent/CN204060615U/en not_active Expired - Fee Related
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104653150A (en) * | 2015-02-04 | 2015-05-27 | 成都科创佳思科技有限公司 | Plugging device |
| CN105507940A (en) * | 2016-01-11 | 2016-04-20 | 山东科技大学 | Slotting, plugging and fracturing integrated type intensified marsh gas extraction device and method |
| CN105507940B (en) * | 2016-01-11 | 2018-01-30 | 山东科技大学 | One kind cuts envelope pressure integration and strengthens gas pumping device and method |
| CN110513100A (en) * | 2019-09-11 | 2019-11-29 | 华北科技学院 | A kind of field experiment method improving gas pressure measurement success rate |
| CN110513100B (en) * | 2019-09-11 | 2023-04-07 | 华北科技学院 | On-site experiment method for improving gas pressure measurement success rate |
| CN112855071A (en) * | 2021-02-04 | 2021-05-28 | 河南理工大学 | Device and method for plugging gas extraction drill hole by using microbial mineralization circulation |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN203430473U (en) | Underground hydraulic fracturing drill hole sealing device of coal mine | |
| CN204060615U (en) | Mine fracturing drilling and sealing device | |
| CN107035401B (en) | A kind of abandoned mine fire damp administers new technology | |
| CN207131371U (en) | Coal mine gas drainage holes controllable capsule bag type hole-sealing device with pressure | |
| CN105822341B (en) | A kind of hypotonic anti-reflection system and method for coal seam supercritical carbon dioxide | |
| CN103195390B (en) | The nearly horizontal mash gas pumping drilling encapsulating method in this coal seam a kind of | |
| CN206722798U (en) | A kind of combined type coal-bed flooding pressure break and gas pumping one hole sealing device | |
| CN103452525A (en) | Gas pumping fixing occluder and use method thereof | |
| CN102926700B (en) | Grouting bag type hole packer with multi-section seal | |
| CN204344065U (en) | The outer fluid filling hole sealing device of a kind of pipe | |
| CN203756114U (en) | Grouting hole packer with capsular bag | |
| CN104295263A (en) | Radial hole sealing device for drill holes for exhausting coal bed gas | |
| CN106761584A (en) | Abandoned mine goaf coal bed gas ground discharge and mining method under a kind of aqueous conditions | |
| CN109681262A (en) | A method of improving gas drilling extraction concentration in broken coal body | |
| CN108678721A (en) | Packaged type hydraulic fracturing and injection hole sealing integrated apparatus and its construction method | |
| CN214836257U (en) | Extraction drilling hole failure hole sealing processing apparatus | |
| CN104696006B (en) | Ground drilling penetrates the method for abandoned coal pillar extraction multilamellar old dead zone remnants coal bed gas | |
| CN112431628A (en) | Drilling gas extraction and hole sealing integrated device and sealing method thereof | |
| CN104963674B (en) | Hypotonic coal seam frozen-thawed cracking anti-reflection method | |
| CN203515458U (en) | Double-hole pipe slurry filling hole sealing device | |
| CN206458334U (en) | Water pumping gas production tubing string | |
| WO2020006870A1 (en) | Gas extraction hole drilling and hole sealing method for building anti-seepage barrier based on grooving-backfilling method | |
| CN105201546A (en) | Device and method for improving gas extraction concentration | |
| CN105019935A (en) | Overground/underground combined pressure relief outburst elimination coal seam rapid channel digging method | |
| CN205677660U (en) | System that a kind of hypotonic coal seam supercritical carbon dioxide is anti-reflection |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20141231 Termination date: 20150919 |
|
| EXPY | Termination of patent right or utility model |