A gas extraction drill rod with extraction device

Abstract

The utility model discloses a kind of gas extraction using drill rod belt extraction device, belong to coal mine safety equipment technical field.The device mainly includes blowout preventer, drill rod, water source, extraction pipe and the tee joint connected in the tail of drill rod.The tee joint is connected with water supply pipe and gas exhaust pipe respectively, and control valve controlled by controller is equipped on each pipeline.Blowout preventer inlet is equipped with pressure sensor.The core of the utility model is that controller can receive pressure signal in real time, when detecting blowout (pressure>0.5MPa), water supply valve can be automatically and quickly closed and gas exhaust valve is opened, drill rod internal passage is switched to gas extraction passage, and high-pressure gas in borehole is directly extracted into current system through gas exhaust pipe.The device realizes the automatic response and disposal of blowout preventer in second level, fundamentally solves the problem of slow response and gas overrun caused by traditional method, and significantly improves the safety and efficiency of borehole operation.

Description

Technical Field

[0001] This utility model belongs to the technical field of gas extraction equipment, specifically relating to a gas extraction device using a drill pipe with extraction mechanism. Background Technology

[0002] As coal mining depths increase and excavation work extends, coal seams are showing a trend of gradually increasing gas content and pressure. During gas drainage drilling, blowouts frequently occur, often leading to localized gas exceedances, borehole blockages, and drill bit jamming, severely impacting drilling progress and, more importantly, posing safety hazards to production.

[0003] If a blowout occurs, the large amount of gas accumulated inside cannot be quickly extracted, posing a danger to production. Although blowout prevention devices are installed at the borehole opening, existing technology has the following inherent drawbacks:

[0004] Response lag: The discovery of the blowout relies on manual observation, and there is a delay of minutes from occurrence to taking action, which cannot contain the initial violent gas outburst.

[0005] Passive handling: Traditional blowout preventer devices can only passively extract gas that has already been ejected to the orifice, and cannot directly and quickly drain the high-pressure gas accumulated inside the borehole.

[0006] Interruption of operations: When dealing with blowouts, drilling often needs to be stopped and the drill rod removed. This process can easily cause gas to leak out of the hole instantly, resulting in excessive gas levels in the return airflow and severely slowing down the tunneling efficiency.

[0007] Therefore, there is an urgent need for an active safety device that can automatically and quickly respond to the blowout and directly remove the gas inside the borehole without interrupting the drilling operation. Utility Model Content

[0008] The present invention aims to address the shortcomings of the prior art by providing a gas extraction device using a drill pipe with extraction mechanism.

[0009] The technical solution adopted in this utility model is:

[0010] A gas extraction device using a drill rod with extraction mechanism includes a blowout preventer, an extraction pipe, a drill rod, and a water source. The blowout preventer is located at the borehole position and is connected to the extraction pipe. The tail end of the drill rod is connected to the water source via a water pipe.

[0011] A tee is connected to the tail of the drill rod. The first end of the tee is connected to the drill rod, the second end is connected to a water source through a water pipe, and the third end is connected to a manifold through a gas drain pipe.

[0012] A first control valve is provided on the connecting pipe between the drill rod and the tee, a second control valve is provided on the water pipe, and a third control valve is provided on the gas discharge pipe;

[0013] The device also includes a controller and a pressure sensor disposed at the air inlet of the blowout preventer.

[0014] The controller is communicatively connected to the pressure sensor, the first control valve, the second control valve, and the third control valve;

[0015] The controller is configured to: in response to a pressure value detected by a pressure sensor, perform a nozzle control operation when the pressure value exceeds a first preset threshold, the nozzle control operation including closing a second control valve and opening a third control valve.

[0016] Furthermore, the first control valve, the second control valve, and the third control valve are all solenoid valves.

[0017] Furthermore, the controller is also configured to: after performing the nozzle control operation, in response to the pressure value detected by the pressure sensor being lower than a second preset threshold, perform a recovery operation, the recovery operation including closing the third control valve and opening the second control valve.

[0018] Furthermore, the execution of the recovery operation also depends on the pressure value remaining below a second preset threshold for a predetermined period of time.

[0019] Furthermore, the first preset threshold is 0.5 MPa.

[0020] Furthermore, the tee is connected to the tail of the drill rod via a rubber hose.

[0021] Furthermore, the manifold is externally connected to a negative pressure suction device.

[0022] Compared with the prior art, the beneficial effects of this utility model are:

[0023] 1. This utility model reduces the response time of the nozzle from the manually judged "minute level" (45-60 seconds) to "second level" (<3 seconds) through closed-loop automatic control of "pressure sensor → controller → control valve", thereby curbing the rapid gas outburst from the source.

[0024] 2. When a blowout occurs, this invention quickly switches the internal channel of the drill pipe from a water supply channel to a gas extraction channel, achieving targeted and direct extraction of high-pressure gas inside the borehole, preventing it from spreading into the roadway space. Field tests show that the highest gas concentration in the return airflow during a blowout is only 0.35%, consistently remaining within the safety regulations' limits.

[0025] 3. The process of spraying holes in this utility model is completed automatically without stopping drilling or removing the drill rod. The processing time for a single spraying hole is reduced from about 25 minutes to about 5 minutes, the average effective drilling time per hole is reduced by about 28%, and the failure of stuck drill and blocked hole caused by gas accumulation is effectively avoided.

[0026] 4. This utility model has a simple structure, only requiring the addition of a tee and a control valve to the existing drill pipe tail section, which can be implemented using a mature PLC or embedded controller. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the structure of a drill pipe used in existing gas extraction technology;

[0028] Figure 2 This is a schematic diagram of the structure of this utility model;

[0029] In the diagram: 1. Blowout preventer; 2. Extraction pipe; 3. Drill rod; 4. Operating vehicle; 5. Water source; 6. Water pipe; 7. Manifold; 8. Tee; 9. First shut-off valve; 10. Second shut-off valve; 11. Third shut-off valve; 12. Gas discharge pipe. Detailed Implementation

[0030] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0031] like Figure 2 As shown, a gas extraction device using a drill rod includes a blowout preventer 1, an extraction pipe 2, a drill rod 3, an operating vehicle 4, and a water source 5. The blowout preventer 1 is fixed to the roadway wall at the borehole location by anchor bolts or the like, and its outlet is connected to the extraction pipe 2 for conventional borehole gas extraction. The tail end of the drill rod 3 is connected to the water source 5 via a high-pressure water pipe 6.

[0032] The key improvement in this embodiment is that a 19mm diameter tee is connected to the tail of the drill rod 3 via a high-pressure resistant rubber hose. The first end (port A) of the tee 8 is connected to the tail of the drill rod 3 via the hose, the second end (port B) is connected to the water source 5 via the water pipe 6, and the third end (port C) is connected to the gas drainage network manifold 7 in the mine via the gas discharge pipe 12. The manifold 7 is externally connected to a high-power negative pressure suction device.

[0033] A first control valve 9 is installed on the connecting pipe between drill pipe 3 and tee 8 to isolate the drill pipe during maintenance or emergencies. A second control valve 11 is installed on water pipe 6 to control the opening and closing of the water supply path. A third control valve 10 is installed on gas vent pipe 12 to control the opening and closing of the gas vent path. In this embodiment, the first control valve 9, the second control valve 11, and the third control valve 10 are all normally open two-position two-way solenoid valves (when using the second control valve 11 and the third control valve 10, the first control valve 9 can remain normally open, with a fast response speed, suitable for automated control).

[0034] A pressure sensor is installed inside the air inlet (i.e., the end facing the borehole) of the blowout preventer device 1 to monitor the gas pressure inside the borehole in real time.

[0035] The controller's control logic is configured as follows:

[0036] Initialization: The system starts up, the controller opens the first control valve 9 and the second control valve 11, and closes the third control valve 10, and the drill rod is in normal drilling water supply mode.

[0037] Continuous monitoring: The controller continuously reads the pressure values ​​from the pressure sensor.

[0038] Orifice detection and handling: When the detected pressure value is >0.5MPa (first preset threshold), the controller determines that an orifice has occurred and immediately executes the following sequence of operations:

[0039] A. Send a shut-off signal to the second control valve 11 to cut off the water supply;

[0040] B. Delay for 0.5 seconds (after ensuring the water circuit is completely closed, send an opening signal to the third control valve 10 to open the gas discharge passage).

[0041] At this time, the high-pressure gas in the borehole is efficiently drawn into the manifold 7 through the inside of the drill rod 3, the tee 8, and the gas discharge pipe 12, thus achieving safe drainage;

[0042] Status Recovery: After opening the gas venting passage, the controller continues to monitor the pressure value. When the pressure value P remains below 0.2 MPa (the second preset threshold) for 10 seconds (a predetermined time), the controller determines that the nozzle treatment is complete and immediately executes the recovery operation.

[0043] A. Send a shut-off signal to the third control valve 10 to cut off the gas venting passage.

[0044] B. After a delay of 0.5 seconds, an opening signal is sent to the second control valve 11 to restore water supply.

[0045] The system automatically returns to normal drilling mode.

[0046] To verify the practical effectiveness of this invention, a field comparative test was conducted in a deep mine (burial depth -850m, coal seam gas pressure 1.8MPa). The test compared the performance of the traditional drill pipe device and the drill pipe with pumping device of this invention, which is equipped with a three-way valve for automatic switching, under the same geological conditions.

[0047] 1. Experimental conditions and methods

[0048] Experimental group: The device of this embodiment was used, and the controller pressure threshold was set to 0.5MPa.

[0049] Control group: The conventional drill pipe device (i.e., as described in the background art, water is supplied only through the drill pipe and passively extracted by the blowout preventer at the orifice).

[0050] Monitoring indicators: nozzle response time, return air gas concentration, and effective drilling time per hole.

[0051] Data collection: Data from 10 valid nozzle events were collected for each group, and the average value was taken.

[0052] The experimental test results are shown in the table below:

[0053] Nozzle response time Manual judgment and attempt to process takes an average of 45-60 seconds. <3 seconds (automatic detection and switching) Response speed improved by approximately 95%. Gas concentration in return air during nozzle operation Average 0.78% (frequent over-limit) Maximum 0.35% (stable within a safe range) Gas concentration reduced by 55% Single nozzle processing time Approximately 25 minutes (operation must be stopped and pressure manually released) Approximately 5 minutes (the system completes automatically, with minimal interruption during drilling). Processing efficiency increased by 80% Average effective drilling time per hole Approximately 2.5 hours (interrupted due to excessive gas levels at the nozzles). Approximately 1.8 hours Drilling efficiency improved by approximately 28%. Stuck drill / blocked hole incidence It occurred 3 times in 10 experiments 0 occurrences in 10 experiments Effectively avoid construction failures

[0054] Experimental results demonstrate that this invention, through closed-loop automatic control of "pressure signal from the anti-blowout device → controller → solenoid valve," improves the blowout response from "minutes" to "seconds," fundamentally avoiding the risk of gas accumulation caused by human judgment and operational delays.

[0055] During the injection process, the methane concentration in the return airflow remained consistently below the 1.0% safety limit stipulated in the "Coal Mine Safety Regulations," demonstrating that this embodiment can effectively control methane diffusion and prevent over-limit accidents.

[0056] The significant reduction in single-hole drilling time (28% increase in efficiency and avoidance of stuck drill failures) directly translates into faster production progress and lower equipment maintenance costs, resulting in significant economic benefits.

[0057] Therefore, this utility model, through the combination of structural innovation and automatic control logic, has solved the long-standing technical problems of "slow nozzle response, easy gas exceedance, and low drilling efficiency" in the process of drilling deep coal seam gas, and has achieved unexpected technical results.

[0058] The working process of this utility model:

[0059] During normal drilling: Drill rod 3 performs drilling operations, third shut-off valve 11 is opened, second shut-off valve 10 is closed, and water source 5 supplies water to drill rod 3 through water pipe 6 for cooling the drill bit and removing cuttings. Blowout preventer 1 is installed at the borehole opening to prevent gas from escaping and extracts gas from the borehole opening through extraction pipe 2.

[0060] When a blowout occurs: Blowout prevention device 1 detects a blowout phenomenon, such as a sudden increase in gas pressure, and transmits a signal to the controller. The controller first closes the third shut-off valve 11, cutting off the water supply to water source 5; then it opens the second shut-off valve 10, allowing the gas in the borehole to enter the manifold 7 through the internal channel of drill rod 3, tee 8, and gas discharge pipe 12, where it is quickly extracted by an external suction device. In this way, the gas accumulated in the borehole is directly discharged, preventing it from spreading into the roadway and preventing gas levels from exceeding limits.

[0061] After the blowout treatment is completed: the controller controls the second shut-off valve 10 to close based on the feedback signal from the blowout prevention device 1, such as when the gas pressure returns to normal, and then controls the third shut-off valve 11 to open, restoring water supply and continuing normal drilling operations.

[0062] Throughout the process, the first shut-off valve 9 can be used to isolate the drill pipe 3 from the tee 8, and can be manually or automatically closed in maintenance or emergency situations, improving system flexibility.

[0063] This invention achieves rapid response and safe handling of the nozzle by automatically controlling valve switching, significantly improving the safety and efficiency of gas extraction.

Claims

1. A gas extraction device with a drill rod and extraction device, comprising a blowout preventer (1), an extraction pipe (2), a drill rod (3) and a water source (5), wherein the blowout preventer (1) is installed at the drilling position, the blowout preventer (1) is connected to the extraction pipe (2), and the tail of the drill rod (3) is connected to the water source (5) through a water pipe (6). Its features are, A tee (8) is connected to the tail of the drill rod (3). The first end of the tee (8) is connected to the drill rod (3), the second end is connected to the water source (5) through the water pipe (6), and the third end is connected to the manifold (7) through the gas drain pipe (12). A first control valve (9) is provided on the connecting pipe between the drill rod (3) and the tee (8), a second control valve (11) is provided on the water pipe (6), and a third control valve (10) is provided on the gas discharge pipe (12). The device also includes a controller and a pressure sensor disposed at the air inlet of the blowout preventer (1); The controller is communicatively connected to the pressure sensor, the first control valve (9), the second control valve (11), and the third control valve (10); The controller is configured to: in response to a pressure value detected by a pressure sensor, perform a nozzle control operation when the pressure value exceeds a first preset threshold, the nozzle control operation including closing the second control valve (11) and opening the third control valve (10).

2. The gas extraction device using a drill pipe with extraction mechanism according to claim 1, characterized in that, The first control valve (9), the second control valve (11) and the third control valve (10) are all solenoid valves.

3. The gas extraction device according to claim 1, characterized in that, The controller is also configured to: after performing the nozzle control operation, in response to the pressure value detected by the pressure sensor being lower than a second preset threshold, perform a recovery operation, the recovery operation including closing the third control valve (10) and opening the second control valve (11).

4. The gas extraction device according to claim 3, characterized in that, The execution of the recovery operation also depends on the pressure value remaining below the second preset threshold for a predetermined period of time.

5. The gas extraction device using a drill pipe with extraction mechanism according to claim 1, characterized in that, The first preset threshold is 0.5 MPa.

6. The gas extraction device using a drill pipe with extraction mechanism according to claim 1, characterized in that, The tee (8) is connected to the tail of the drill rod (3) via a rubber hose.

7. The gas extraction device using a drill pipe with extraction mechanism according to claim 1, characterized in that, The manifold (7) is connected to an external negative pressure suction device.

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