Drilling equipment and drilling construction method

Abstract

The present invention relates to a drilling device and a drilling construction method, comprising the following steps: drilling a target rock formation using a pilot drill to form a grouting channel; injecting slurry into the grouting channel using the pilot drill to fill the grouting channel and surrounding rock gaps; after the slurry solidifies, reaming the grouting channel using a reaming drill bit to form a target borehole; and reversing the reaming drill bit and the pilot drill to remove the reaming drill bit and the pilot drill from the target borehole. The drilling construction method of the present invention has a simple operating process, achieves good reinforcement and repair effects on the surrounding rock around the borehole, ensures the stability of the reaming drilled hole and prevents collapse, and has low construction costs.

Description

Technical Field

[0001] The present invention relates to the technical field of drilling construction, in particular to a drilling device and a drilling construction method. Background Art

[0002] In natural gas extraction and fracturing decompression projects, borehole collapse is a common problem faced by drilling operations. Once a borehole is formed and a fracturing device is installed, collapse can lead to accidents such as the inability to recover the fracturing device and the inability to carry out the fracturing project. Therefore, to ensure the smooth progress of subsequent projects after the borehole is opened, the borehole needs to be reinforced to prevent the problem of borehole collapse. However, the related drilling reinforcement process is complex, the construction cycle is long, and the construction cost of long-distance drilling is high. Summary of the Invention

[0003] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0004] To this end, an embodiment of the present invention proposes a drilling construction method, which has a simple operation process, good surrounding rock reinforcement and repair effects around the borehole, ensures that the expanded borehole is stable and does not collapse, and has low construction costs.

[0005] An embodiment of the present invention further provides a drilling device.

[0006] The drilling construction method according to an embodiment of the present invention comprises the following steps:

[0007] Drilling the target rock formation by a pilot drill to form a grouting channel;

[0008] injecting slurry into the grouting channel through the pilot drill to fill the grouting channel and the surrounding rock gaps around the grouting channel;

[0009] After the slurry solidifies, the grouting channel is enlarged by a reaming drill bit to form a target borehole;

[0010] The reaming drill bit and the pilot drill are reversed to withdraw the reaming drill bit and the pilot drill from the target borehole.

[0011] According to the drilling construction method of an embodiment of the present invention, a pilot drill can be used to drill a hole and form a grouting channel, and slurry can be injected into the grouting channel so that the grouting channel and the surrounding rock gaps around the grouting channel can be filled with slurry. After the slurry solidifies, the grouting channel and the surrounding rock formations can be bonded and strengthened. The grouting channel can then be drilled a second time using a reaming drill bit to make the structure of the target borehole formed more stable, avoiding the problem of borehole collapse. In addition, the operation process of the above-mentioned construction method is simple, the surrounding rock reinforcement and repair effect around the borehole is good, and the reaming drilling is ensured to be stable and not collapse, and the construction cost is low.

[0012] In some embodiments, the slurry includes a first reaction slurry and a second reaction slurry, the solidification rate of the first reaction slurry is higher than the solidification rate of the second reaction slurry, and “injecting slurry into the grouting channel through the pilot drill to fill the grouting channel and the surrounding rock around the grouting channel” includes the following steps:

[0013] injecting a first reaction slurry into the grouting channel through the pilot drill;

[0014] sealing the first reaction slurry at the opening of the grouting channel;

[0015] The second reaction slurry is injected into the grouting channel through the pilot drill, and the second reaction slurry penetrates into the surrounding rock cracks due to the pressure in the grouting channel.

[0016] In some embodiments, the first reaction slurry is thixotropic and can form a paste state. The first reaction slurry does not flow when there is no grouting pressure, and can form a shape that contacts the grouting channel. After solidification, it will expand to seal the opening of the grouting channel.

[0017] In some embodiments, the slurry penetrates into the surrounding rock cracks to form a reinforcement layer, and the radial dimension of the reinforcement layer along the target borehole is greater than or equal to 50 mm and less than or equal to 100 mm.

[0018] In some embodiments, the pilot drill rig includes a drill rod and a pilot drill bit, the pilot drill bit is arranged at one end of the drill rod, the reaming drill bit is coaxially arranged on the drill rod and is movable along the length direction of the drill rod, the diameter of the pilot drill bit is D1, and the diameter of the reaming drill bit is D2, wherein 2≤D2 / D1≤4.

[0019] In some embodiments, the reaming drill bit is threadedly connected to the drill rod.

[0020] In some embodiments, a drainage channel is provided in the drill rod, and a water pump and a slurry pump are provided at the end of the drill rod, and both the water pump and the slurry pump are connected to the drainage channel.

[0021] When the pilot drill bit and / or the reaming drill bit is drilling, the water pump supplies water into the drainage channel to flush the borehole;

[0022] When injecting slurry into the grouting channel, the slurry pump supplies slurry into the drainage channel, so that the grouting channel and the surrounding rock gaps are filled with slurry.

[0023] In some embodiments, a nozzle is provided on the drill rod, and there is at least one nozzle. The nozzle is provided at one end of the drill rod adjacent to the pilot drill bit and is connected to the drainage channel.

[0024] According to another embodiment of the present invention, the drilling equipment includes: a pilot drill, the pilot drill includes a drill rod and a pilot drill bit, the pilot drill bit is arranged at one end of the drill rod, a drainage channel is provided in the drill rod, a nozzle is provided on the drill rod, the nozzle is provided at one end of the drill rod adjacent to the pilot drill bit and is connected to the drainage channel; a reaming drill bit, the reaming drill bit is provided on the drill rod and is movable along the length of the drill rod, the diameter of the reaming drill bit is larger than the diameter of the pilot drill bit.

[0025] According to the drilling equipment of the embodiment of the present invention, a pilot drill can be used to drill a hole and form a grouting channel, and slurry can be injected into the grouting channel so that the grouting channel and the surrounding rock gaps around the grouting channel can be filled with slurry. After the slurry solidifies, the grouting channel and the surrounding rock formations can be bonded and strengthened. The grouting channel can then be drilled a second time using a reaming drill bit to make the structure of the target borehole formed more stable and avoid the problem of borehole collapse. Therefore, the drilling equipment of the embodiment of the present invention is easy to operate, resulting in a better reinforcement effect of the surrounding rock around the borehole and low construction costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of a grouting channel before grouting in the drilling construction method according to an embodiment of the present invention.

[0027] Figure 2 It is a schematic diagram of the grouting channel after grouting in the drilling construction method according to an embodiment of the present invention.

[0028] Figure 3 It is a schematic diagram of the drilling construction method according to an embodiment of the present invention when drilling into a target borehole.

[0029] Figure 4 It is a process flow chart of the drilling construction method according to an embodiment of the present invention.

[0030] Reference numerals:

[0031] 1. Pilot drilling rig; 11. Drill rod; 111. Drain channel; 12. Pilot drill bit;

[0032] 2. Reaming drill bit.

[0033] 3. Grouting channel;

[0034] 4. Target drilling;

[0035] 5. Reinforcement layer. DETAILED DESCRIPTION

[0036] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0037] Please refer to the following Figures 1 to 4 A drilling device and a drilling construction method according to an embodiment of the present invention are described.

[0038] like Figures 1 to 4 As shown, the drilling construction method according to an embodiment of the present invention includes the following steps:

[0039] S1: Drilling the target rock formation by a pilot drill 1 to form a grouting channel 3;

[0040] S2: injecting slurry into the grouting channel 3 through the pilot drill 1 to fill the grouting channel 3 and the surrounding rock cracks around the grouting channel 3;

[0041] S3: After the slurry solidifies, the grouting channel 3 is enlarged by the reaming drill bit 2 to form a target borehole 4;

[0042] S4 : Reverse the reaming drill bit 2 and the pilot drill 1 to withdraw the reaming drill bit 2 and the pilot drill 1 from the target borehole 4 .

[0043] According to the drilling construction method of the embodiment of the present invention, a pilot drill 1 can be used to drill a hole and form a grouting channel 3, and slurry can be injected into the grouting channel 3 so that the grouting channel 3 and the surrounding rock gaps around the grouting channel 3 can be filled with slurry. After the slurry solidifies, the grouting channel 3 and the surrounding rock formations can be bonded and strengthened. Then, the grouting channel 3 can be drilled a second time by the reaming drill bit 2 to make the structure of the target borehole 4 formed finally more stable, avoiding the problem of borehole collapse. In addition, the operation process of the above-mentioned construction method is simple, the surrounding rock reinforcement and repair effect around the borehole is good, ensuring that the reaming drilling is stable and does not collapse, and the construction cost is low.

[0044] It is understandable that if Figures 1 to 3As shown, the drilling construction method of an embodiment of the present invention drills a small-diameter pilot hole to form a grouting channel 3. By injecting a thixotropic grouting material under pressure, the grouting channel 3 is filled and the cracks in the broken surrounding rock are filled, bonded, and strengthened to reinforce the surrounding rock around the borehole. Later, a reaming drill bit 2 is used to perform a secondary drilling on the reinforced surrounding rock to form a target borehole 4 in which the fracturing device can be installed. Therefore, the drilling construction method of an embodiment of the present invention can achieve long borehole consolidation. Without the borehole collapsing, the fracturing device can be successfully installed, completed, and safely recovered, ultimately ensuring the smooth implementation of the fracturing project.

[0045] Optionally, the slurry includes a first reaction slurry and a second reaction slurry, and the first reaction slurry solidifies faster than the second reaction slurry. In other words, the first reaction slurry solidifies faster than the second reaction slurry. "Injecting slurry into the grouting channel 3 using the pilot drill 1 to fill the grouting channel 3 and the surrounding rock surrounding the grouting channel 3" includes the following steps:

[0046] Injecting the first reaction slurry into the grouting channel 3 through the pilot drill 1;

[0047] The first reaction slurry is sealed at the opening of the grouting channel 3;

[0048] The second reaction slurry is injected into the grouting channel 3 through the pilot drill 1 , and the second reaction slurry penetrates into the surrounding rock cracks due to the pressure in the grouting channel 3 .

[0049] Specifically, the first reaction slurry is thixotropic and can form a paste state. The first reaction slurry does not flow when there is no grouting pressure, and can form a shape that contacts the grouting channel 3. After solidification, it will expand to seal the opening of the grouting channel 3.

[0050] It is understandable that the drilling construction method of the embodiment of the present invention can first inject the first reaction slurry (fast reaction material) and then inject the second reaction slurry (slow reaction material). The first reaction slurry forms a sealing effect near the hole mouth, and the second reaction slurry plays a role in promoting the movement of the first reaction slurry in the early stage. Then the first reaction slurry seals the hole mouth so that the second reaction slurry can be grouted under pressure and penetrate into the cracks in the surrounding rock to achieve reinforcement of the surrounding rock. When the material in the borehole and the cracks is completely solidified, the reaming drill bit 2 is used for secondary drilling. The reaming drill bit 2 is rotated and the internal thread of the drill bit is engaged with the drill rod 11 to advance and realize reaming drilling. At this time, the surrounding rock has been reinforced and strengthened and will not collapse again, so as to ensure the subsequent installation of the fracturing device and carry out subsequent construction.

[0051] Alternatively, as Figure 2 and Figure 3As shown, the slurry penetrates into the cracks in the surrounding rock to form a reinforcement layer 5. The reinforcement layer 5 can repair the original broken surrounding rock to ensure that the surrounding rock will not collapse during hole expansion and drilling. The radial dimension of the reinforcement layer 5 along the target borehole 4 is greater than or equal to 50 mm and less than or equal to 100 mm. In other words, the radial dimension of the slurry penetrating into the cracks in the surrounding rock is greater than or equal to 50 mm and less than or equal to 100 mm. The inventors of the present application have found through experiments that when the radial dimension of the slurry penetrating into the cracks in the surrounding rock meets the above-mentioned value, the structure of the borehole can be made more stable and the consumption of slurry can be reduced, resulting in lower construction costs.

[0052] In some embodiments, as Figure 3 As shown, the pilot drill rig 1 includes a drill rod 11 and a pilot drill bit 12. The pilot drill bit 12 is provided at one end of the drill rod 11. The reaming drill bit 2 is coaxially provided on the drill rod 11 and is movable along the length direction of the drill rod 11. The diameter of the pilot drill bit 12 is D1, and the diameter of the reaming drill bit 2 is D2, wherein 2≤D2 / D1≤4. For example, the ratio of D2 / D1 can be 2, 3 or 4. In an embodiment of the present invention, the diameter of the pilot drill bit 12 can be 46 mm, and the diameter of the reaming drill bit 2 is 150 mm. The inventors of the present application have found through experiments that when D2 / D1 satisfies the above ratio, the work efficiency during drilling construction can be higher and the drilling effect can be better.

[0053] Alternatively, as Figures 1 to 3 As shown, a drainage channel 111 is provided in the drill rod 11, and a water pump (not shown) and a slurry pump (not shown) are provided at the end of the drill rod 11, and the water pump and the slurry pump are connected to the drainage channel 111. When the pilot drill bit 12 and the reaming drill bit 2 are drilling, the water pump supplies water to the drainage channel 111 to flush the borehole. When injecting slurry into the grouting channel 3, the slurry pump supplies slurry into the drainage channel 111 so that the grouting channel 3 and the surrounding rock gaps are filled with slurry. It can be understood that the operator can inject different liquids into the drainage channel 111 according to actual construction needs. The construction operation is simple, and it is convenient for the processing and manufacturing of the drill rod 11, and the construction cost is low.

[0054] Alternatively, as Figure 1 As shown, a nozzle (not shown) is provided on the drill rod 11, and the nozzle is provided at one end of the drill rod 11 adjacent to the pilot drill bit 12 (as shown in FIG. Figure 1 The right end of the middle drill rod 11) is connected to the drainage channel 111. When the pilot drill bit 12 and the reaming drill bit 2 are drilling, the nozzle can spray water into the borehole to clean the drill bits. When injecting slurry into the grouting channel 3, the slurry can be injected into the borehole through the nozzle. There can be one or more nozzles, which is not limited in this application.

[0055] like Figures 1 to 3As shown, a drilling apparatus according to another embodiment of the present invention includes a pilot drill 1 and a reaming drill bit 2. The pilot drill 1 includes a drill rod 11 and a pilot drill bit 12. The pilot drill bit 12 is disposed at one end of the drill rod 11. The drill rod 11 is provided with a drainage channel 111. The drill rod 11 is provided with a nozzle. The nozzle is disposed at one end of the drill rod 11 adjacent to the pilot drill bit 12 and communicates with the drainage channel 111. The reaming drill bit 2 is disposed on the drill rod 11 and is movable along the length of the drill rod 11. The diameter of the reaming drill bit 2 is larger than that of the pilot drill bit 12.

[0056] According to the drilling equipment of the embodiment of the present invention, a pilot drill 1 can be used to drill a hole and form a grouting channel 3, and slurry can be injected into the grouting channel 3 so that the grouting channel 3 and the surrounding rock gaps around the grouting channel 3 can be filled with slurry. After the slurry solidifies, the grouting channel 3 and the surrounding rock formations can be bonded and strengthened. The grouting channel 3 can then be drilled a second time using the reaming drill bit 2 to make the structure of the target borehole 4 formed in the end more stable, thereby avoiding the problem of borehole collapse. Therefore, the drilling equipment of the embodiment of the present invention is easy to operate, resulting in a better reinforcement effect of the surrounding rock around the borehole and a lower construction cost.

[0057] Optionally, the diameter of the pilot drill bit 12 is D1, and the diameter of the reaming drill bit 2 is D2, where 2 ≤ D2 / D1 ≤ 4. For example, the ratio D2 / D1 can be 2, 3, or 4. In an embodiment of the present invention, the diameter of the pilot drill bit 12 can be 46 mm, and the diameter of the reaming drill bit 2 can be 150 mm. The inventors of this application have discovered through experiments that when D2 / D1 satisfies the above ratio, drilling efficiency can be increased and drilling results can be improved.

[0058] Optionally, the reaming drill bit 2 is threadedly connected to the drill rod 11. It is understood that the inner wall of the reaming drill bit 2 is provided with an internal thread, and the outer wall of the drill rod 11 is provided with an external thread, and the external thread cooperates with the internal thread, so that the reaming drill bit 2 can be rotated relative to the drill rod 11, so that the reaming drill bit 2 moves along the length direction of the drill rod 11 to expand the rock formation.

[0059] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0060] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0061] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or communication; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0062] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0063] In the present invention, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples without contradiction.

[0064] Although the above embodiments have been shown and described, it is understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. Changes, modifications, substitutions and variations of the above embodiments by those skilled in the art are all within the scope of protection of the present invention.

Claims

1. A drilling construction method, characterized in that: The drilling equipment used in the drilling construction method includes a pilot drill and a reaming drill bit. The pilot drill includes a drill rod and a pilot drill bit. The pilot drill bit is provided at one end of the drill rod. The reaming drill bit is coaxially provided on the drill rod and is movable along the length of the drill rod. The reaming drill bit is threadedly connected to the drill rod. The diameter of the pilot drill bit is D1, and the diameter of the reaming drill bit is D2, wherein 2≤D2 / D1≤4; The drilling construction method comprises the following steps: Drilling the target rock formation by a pilot drill to form a grouting channel; Injecting slurry into the grouting channel through the pilot drill to fill the grouting channel and surrounding rock cracks around the grouting channel, the slurry comprising a first reactive slurry and a second reactive slurry, the first reactive slurry having a higher solidification rate than the second reactive slurry, the first reactive slurry having thixotropy and being capable of forming a paste state, the first reactive slurry not flowing in the absence of grouting pressure, and being capable of forming a shape in contact with the grouting channel, and expanding after solidification to seal the opening of the grouting channel; After the slurry solidifies, the grouting channel is enlarged by a reaming drill bit to form a target borehole; Reversing the reaming drill bit and the pilot drill to withdraw the reaming drill bit and the pilot drill from the target borehole; “Injecting slurry into the grouting channel through the pilot drilling rig to fill the grouting channel and the surrounding rock around the grouting channel” includes the following steps: injecting a first reaction slurry into the grouting channel through the pilot drill; sealing the first reaction slurry at the opening of the grouting channel; Injecting a second reaction slurry into the grouting channel through the pilot drill, wherein the second reaction slurry penetrates into the surrounding rock cracks due to the pressure in the grouting channel; By first injecting the first reaction slurry and then injecting the second reaction slurry, the first reaction slurry forms a sealing effect near the opening, the second reaction slurry pushes the first reaction slurry to move in the early stage, and then the first reaction slurry seals the hole so that the second reaction slurry can be grouted under pressure and penetrate into the cracks of the surrounding rock, thereby achieving reinforcement of the surrounding rock.

2. The drilling construction method according to claim 1, characterized in that: The slurry penetrates into the surrounding rock cracks to form a reinforcement layer, and the radial dimension of the reinforcement layer along the target borehole is greater than or equal to 50 mm and less than or equal to 100 mm.

3. The drilling construction method according to claim 1, characterized in that: A drainage channel is provided in the drill rod, and a water pump and a slurry pump are provided at the end of the drill rod, both of which are connected to the drainage channel. When the pilot drill bit and / or the reaming drill bit is drilling, the water pump supplies water into the drainage channel to flush the borehole; When injecting slurry into the grouting channel, the slurry pump supplies slurry into the drainage channel, so that the grouting channel and the surrounding rock gaps are filled with slurry.

4. The drilling construction method according to claim 3, characterized in that: The drill rod is provided with a nozzle, and there is at least one nozzle. The nozzle is provided at one end of the drill rod adjacent to the pilot drill bit and is communicated with the drainage channel.

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