Drill tail gas extraction pressure relief device

Abstract

The utility model discloses a kind of drilling tail gas extraction pressure relief devices, including one inside coal-water gas separation tank of negative pressure state, its inlet is communicated to the orifice blowout preventer of drilling device through slag outlet pipe, and its top outlet is communicated to extraction blowout preventer pipeline;Coal-water gas separation tank is provided with a pressure relief pipe on the side of inlet, and pressure relief pipe is communicated to the first interface pipe of a three-way valve by rubber tube, and pressure relief valve is arranged on the first interface pipe;Wherein, drilling tail gas extraction pressure relief device, for before needing to increase drill rod, dismounting water tail pipe joint, by opening pressure relief valve to extract the gas existing in the tail of drill rod. It solves the problem of gas leakage when dismounting drill rod water tail.

Description

Technical Field

[0001] This utility model belongs to the field of coal mine gas extraction and drilling safety technology, specifically relating to a gas extraction and pressure relief device for the drill tail. Background Technology

[0002] In underground coal mine drilling operations, existing technologies have significant shortcomings when it is necessary to disassemble the tailpipe joint or extend the drill pipe. In traditional operations, high concentrations of methane often accumulate at the drill pipe tail, and existing equipment lacks a dedicated methane extraction and depressurization structure. During the disassembly of the tailpipe or the addition of drill pipe, the lack of an effective methane outlet means that the accumulated methane can be released instantly during the disassembly process, easily leading to methane leaks and seriously threatening underground operational safety. Furthermore, existing methane extraction systems typically only extract methane from the borehole interior, neglecting the specific area at the drill pipe tail, making this area a blind spot for methane management. This methane leakage problem not only increases the risk of methane exceeding limits but can also affect the continuity of drilling operations, forcing frequent interruptions and reducing production efficiency. Utility Model Content

[0003] The purpose of this invention is to provide a gas extraction and depressurization device for the treadmill tail section to solve the problem of gas leakage during the disassembly of the drill pipe tail section.

[0004] The present invention adopts the following technical solution: a gas extraction and depressurization device for the tail of a drill, including a coal-water-gas separation box with a negative pressure state inside, the inlet of which is connected to the blowout prevention device at the orifice of the drilling device through a slag discharge pipe, and the top outlet of which is connected to the extraction and blowout prevention pipeline. A pressure relief pipe is installed next to the inlet of the coal-water-gas separator. The pressure relief pipe is connected to the first interface pipe of a three-way valve through a rubber hose. A pressure relief valve is installed on the first interface pipe. Among them, the tail gas extraction and depressurization device is used to extract gas at the tail of the drill pipe by opening the depressurization valve before adding drill pipe or disassembling tailpipe joint.

[0005] Furthermore, the bottom of the coal-water-gas separator is inclined, and a slag outlet is located at the lowest point of the bottom.

[0006] Furthermore, the second and third interface pipes of the three-way valve are respectively connected to the tailpipe connector and the high-pressure water pipe at the tail of the drill pipe.

[0007] The beneficial effects of this invention are as follows: Before disassembling the tailpipe joint or adding drill pipe, opening the pressure relief valve allows for rapid extraction of gas accumulated at the tail of the drill pipe through the negative pressure state of the coal-water-gas separation box. The gas is introduced into the separation box via the pressure relief pipe, hose, and three-way valve, and then discharged through the extraction blowout prevention pipeline, avoiding the risk of direct gas leakage in traditional operations and eliminating the hidden danger of excessive gas levels at the source. No emergency handling is required after a gas leak; drill pipe extension or disassembly can be performed directly, reducing the number of work interruptions and improving the continuity of drilling operations. Compared with traditional methods, this can increase operational efficiency by approximately 30%.

[0008] The coal-water-gas separator is tilted at the bottom and has a slag outlet, which can separate coal slag, water, and gas generated during drilling while extracting gas, preventing debris from clogging the pipeline and ensuring the long-term stable operation of the extraction system. In addition, the design of the three-way valve connecting to the high-pressure water pipe can switch to flushing mode when necessary, realizing the integration of extraction and pipeline cleaning functions. Attached Figure Description

[0009] Figure 1 This is a schematic diagram of the structure of this utility model.

[0010] Among them, 1. coal-water-gas separator, 2. drill rod, 3. tailpipe connector, 4. three-way valve, 5. high-pressure water pipe, 6. pressure relief valve, 7. rubber hose, 8. pressure relief pipe, 9. slag outlet, 10. extraction blowout prevention pipeline, 11. slag outlet pipe, 12. orifice blowout prevention device. Detailed Implementation

[0011] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0012] This utility model provides another type of gas extraction and depressurization device for drill tails, such as... Figure 1 As shown, it includes a coal-water-gas separator 1 with an internal negative pressure state. Its inlet is connected to the blowout preventer 12 of the drilling device through the slag discharge pipe 11, and its top outlet is connected to the extraction blowout preventer pipeline 10. A pressure relief pipe 8 is installed next to the inlet of the coal-water-gas separator 1. The pressure relief pipe 8 is connected to the first interface pipe of a three-way valve 4 through a rubber hose 7. A pressure relief valve 6 is installed on the first interface pipe. Among them, the gas extraction and depressurization device at the treadmill tail is used to extract the gas at the tail of the drill rod 2 by opening the depressurization valve 6 before adding the drill rod 2 or disassembling the tailpipe joint 3.

[0013] A complete gas extraction pathway is formed through the interconnected design of the negative pressure coal-water-gas separator, slag discharge pipe, and extraction blowout prevention pipeline. The pressure relief pipe is connected to the drill pipe tail via a rubber hose and a three-way valve. Before drilling, the pressure relief valve can be opened to extract gas accumulated at the drill tail using the negative pressure of the separator, avoiding gas leakage when disassembling the water tail or connecting the drill pipe. This eliminates safety hazards at the source, ensures the safety of downhole operations, and has a high degree of structural integration, making it compatible with existing drilling equipment.

[0014] In some embodiments, the bottom of the coal-water-gas separator 1 is inclined, and a slag outlet 9 is provided at the lowest position of the bottom.

[0015] The coal-water-gas separator has an inclined bottom and a slag outlet. During gas extraction, gravity causes coal slag to accumulate at the lowest point and be easily discharged through the outlet. This design prevents coal slag from accumulating and clogging the pipelines, ensuring unobstructed gas extraction channels, improving the continuous operation of the unit, reducing the frequency of manual cleaning, lowering maintenance costs, achieving efficient separation of gas, water, and slag, and ensuring the long-term stable operation of the extraction system.

[0016] In some embodiments, the second and third interface pipes of the three-way valve 4 are respectively connected to the tailpipe connector 3 and the high-pressure water pipe 5 at the tail of the drill pipe 2.

[0017] The second and third ports of the three-way valve connect to the tailpipe connector and the high-pressure water pipe respectively, allowing for flexible switching of functions. When extracting gas, the high-pressure water is blocked, creating a gas extraction path; during normal drilling, the high-pressure water is connected to provide flushing fluid to the drill pipe. This design integrates the functions of gas extraction and pressure relief with drilling water supply, avoiding additional pipeline modifications, simplifying the operation process, improving the practicality of the device, meeting the needs of different stages of drilling operations, and increasing construction efficiency.

[0018] The steps for using this utility model's tail gas extraction and depressurization device are as follows: Preparation before operation: Connect the inlet of the coal-water-gas separator to the blowout preventer at the borehole opening of the drilling device via the slag discharge pipe, and connect the top outlet to the extraction blowout preventer pipeline to ensure a negative pressure state inside the separator. Connect the pressure relief pipe to the first interface pipe of the three-way valve via a rubber hose. Install the pressure relief valve on the first interface pipe. Connect the second and third interface pipes of the three-way valve to the water tailpipe connector at the drill rod tail and the high-pressure water pipe, respectively, to complete the system integration of the device.

[0019] Drill tail gas extraction: When it is necessary to disassemble the tailpipe joint or add drill rods, first close the passage between the high-pressure water pipe and the tailpipe joint (if in water supply mode), and slowly open the pressure relief valve. At this time, the gas accumulated at the tail of the drill rod, under the negative pressure of the separation box, enters the coal-water-gas separation box through the tailpipe joint, three-way valve, hose, and pressure relief pipe, and is then extracted to the surface gas extraction system through the extraction blowout prevention pipeline. Observe the gas concentration change during the extraction process. Only after the gas concentration at the tail of the drill rod drops to a safe threshold (e.g., below 1%) can the next step be carried out.

[0020] Drill pipe operation and system reset: After gas extraction is completed, dismantle the tailpipe or extend the drill pipe. After the operation is completed, close the pressure relief valve and restore the three-way valve to normal water supply (if drilling needs to continue). Allow the high-pressure water pipe to supply water to the tailpipe joint through the three-way valve to maintain normal water circulation during drilling. Simultaneously, regularly clean the deposited coal slag through the slag outlet at the bottom of the coal-water-gas separator to ensure unobstructed flow in the separator and pipelines.

[0021] Handling Abnormal Situations: If pipeline blockage or gas extraction efficiency is found during the extraction process, the three-way valve can be used to switch to high-pressure water flushing mode. The high-pressure water flow will flush the pipeline, remove debris, and then the extraction state will be restored to ensure the continuous and effective operation of the device.

Claims

1. A gas extraction and depressurization device for drilling tails, characterized in that, It includes a coal-water-gas separator (1) with an internal negative pressure state, whose inlet is connected to the orifice blowout preventer (12) of the drilling device through the slag discharge pipe (11), and whose top outlet is connected to the extraction blowout preventer pipeline (10). A pressure relief pipe (8) is installed next to the inlet of the coal-water-gas separator (1). The pressure relief pipe (8) is connected to the first interface pipe of a three-way valve (4) through a rubber hose (7). A pressure relief valve (6) is installed on the first interface pipe. The gas extraction and depressurization device at the drill tail is used to extract gas at the tail of the drill rod (2) by opening the depressurization valve (6) before adding the drill rod (2) or disassembling the tailpipe joint (3).

2. The tail gas extraction and depressurization device as described in claim 1, characterized in that, The bottom of the coal-water-gas separator (1) is inclined, and a slag outlet (9) is provided at the lowest position of the bottom.

3. The tail gas extraction and depressurization device as described in claim 1 or 2, characterized in that, The second and third interface pipes of the three-way valve (4) are respectively connected to the tailpipe joint (3) and the high-pressure water pipe (5) at the tail of the drill rod (2).

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