Consolidation grouting blanket borehole protection device and method of use

Abstract

The application discloses a kind of consolidated grouting covering layer borehole protection device and use method, the device includes connecting sleeve, support sleeve and drill bit sleeve, connecting sleeve, support sleeve and drill bit sleeve are all hollow cylindrical sleeve, connecting sleeve top is connected with top cover, and the top of connecting sleeve is blocked by top cover, and the upper surface of top cover is connected with drill pipe connecting device;Several drill bits are connected on the bottom ring of drill bit sleeve;Connecting sleeve, support sleeve and drill bit sleeve are connected from top to bottom by screw thread.Connecting sleeve, support sleeve and drill bit sleeve are left in the soil by support sleeve and drill bit sleeve, and support wall is formed by cylindrical sleeve, to avoid the collapse of covering layer and shrinkage hole;Meanwhile, the support sleeve of multiple sections is hollow rigid tube with diameter greater than drill pipe, and screw thread is arranged at both ends, to facilitate lengthening connection when drilling, and to be drilled by drilling machine during construction;Diamond grain drill bit is installed in advance on the sleeve of support sleeve, and diamond grain or drill bit sleeve can be replaced when serious wear occurs in later period.

Description

Technical Field

[0001] This invention belongs to the field of consolidation grouting drilling technology, specifically relating to a consolidation grouting cover layer drilling wall protection device and its usage method. Background Technology

[0002] The overburden refers to loose deposits and sediments of various origins that cover the bedrock, such as layers of sand and gravel, sandy soil, and artificially filled gravelly soil. During consolidation grouting, because the overburden is relatively soft and not dense, borehole collapse and shrinkage are prone to occur during drilling. Therefore, an effective wall protection structure is required to penetrate the overburden.

[0003] For small-diameter orifices, the main types of wall protection include mud slurry wall protection and steel casing wall protection. However, if mud slurry wall protection is used, a large number of mud pits and sedimentation tanks need to be excavated on site, which places high demands on the site. Furthermore, the mud slurry can easily cause environmental pollution during the treatment process, making mud slurry wall protection less suitable. Traditional steel casing wall protection mainly uses a vibratory hammer to drive the steel casing into the cover layer. This requires high equipment investment costs, and the cover layer contains large stones, making the driving process difficult. Furthermore, it is not easy to pull out the casing after grouting.

[0004] Therefore, it is necessary to study a hole wall protection device and construction method suitable for consolidation grouting cover layer drilling to effectively solve the phenomena of hole collapse and hole shrinkage during cover layer drilling. Summary of the Invention

[0005] The purpose of this invention is to provide a device and method for protecting the borehole wall during consolidation grouting, so as to avoid borehole collapse during consolidation grouting.

[0006] The objective of this invention is achieved through the following technical means: a borehole wall protection device for consolidation grouting cover layer, comprising a connecting sleeve, a supporting sleeve, and a drill bit sleeve. The connecting sleeve, supporting sleeve, and drill bit sleeve are all hollow cylindrical sleeves. A top cover is connected to the top of the connecting sleeve, sealing the top of the connecting sleeve. A drill rod connecting device is connected to the upper surface of the top cover. Several drill bits are connected to the bottom ring of the drill bit sleeve. The connecting sleeve, supporting sleeve, and drill bit sleeve are connected from top to bottom by threads.

[0007] The drill bit is a diamond drill bit.

[0008] There are several support sleeves, and the several support sleeves are connected from top to bottom as one unit by threads.

[0009] The bottom of the connecting sleeve is connected to an external thread, and the inner wall of the top of the support sleeve is opened with an internal thread. The bottom of the support sleeve is connected to an external thread, and the inner wall of the top of the drill bit sleeve is opened with an internal thread. The external thread is inserted into the internal thread and matches the internal thread.

[0010] The connecting sleeve is detachably connected to the drill rod via a drill rod connecting device.

[0011] The drill pipe connecting device is a drill bit connecting sleeve, and the inner wall of the drill bit connecting sleeve has threads that match the drill bit.

[0012] A method for using a borehole wall protection device for consolidation grouting cover layer includes the following steps. The device is connected by connecting the connecting sleeve, support sleeve, and drill bit sleeve from top to bottom through threads. The connecting sleeve is then connected to the bottom of the drill rod through the drill bit connecting sleeve. The wall protection device is drilled in, the drill rod is started, and the connecting casing, support casing and drill bit casing are drilled downward through the drill bit at the bottom of the drill bit casing; In drilling operations, the connecting sleeve is separated from the drill rod and the support sleeve. The drill bit is connected to the drill rod and drills through the hollow part inside the support sleeve.

[0013] When the bottom of the connecting sleeve is close to the ground, but the drill bit sleeve has not yet reached the predetermined depth, the support sleeve is replaced, the drill rod stops working, the connecting sleeve is separated from the drill rod, the connecting sleeve is separated from the lower support sleeve, a new support sleeve is reconnected on the uppermost support sleeve, the drill rod, the connecting sleeve and the newly added support sleeve are reconnected, and drilling continues downward. This step is repeated until the drill bit sleeve reaches the predetermined depth, at which point the support sleeve is drilled in and remains in the soil.

[0014] The beneficial effects of this invention are as follows: by leaving the support casing and drill bit casing in the soil, the cylindrical casing forms a supporting wall, effectively preventing hole collapse during consolidation grouting drilling; simultaneously, the multi-section support casing is a hollow rigid tube with a diameter larger than the drill rod, and both ends are threaded, facilitating lengthening during drilling, and is drilled in by a drilling rig; the diamond drill bit is pre-installed on the support casing, and can be replaced with the diamond drill bit or drill bit casing when it becomes severely worn later. This method is more environmentally friendly than previous construction methods, and the casing is drilled in by a drilling rig, eliminating the need for additional equipment; furthermore, the casing can be reused. Attached Figure Description

[0015] Figure 1 Schematic diagram of the borehole wall protection device for consolidation grouting cover layer; Figure 2 This is a schematic diagram of the connecting sleeve structure; Figure 3 This is a schematic diagram of the supporting sleeve structure; Figure 4 This is a schematic diagram of the drill bit casing structure; Figure 5 This is a bottom view of the drill bit casing structure; In the diagram: 1. Connecting sleeve; 2. Support sleeve; 3. Drill bit sleeve; 4. Top cap; 5. Drill bit; 6. Drill bit connecting sleeve; The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Detailed Implementation

[0016] like Figure 1 The device for borehole wall protection of consolidation grouting cover layer shown includes a connecting sleeve 1, a supporting sleeve 2, and a drill bit sleeve 3. The connecting sleeve 1, the supporting sleeve 2, and the drill bit sleeve 3 are all hollow cylindrical sleeves. A top cover 4 is connected to the top of the connecting sleeve 1, and the top cover 4 seals the top of the connecting sleeve 1. A drill rod connecting device is connected to the upper surface of the top cover 4. Several drill bits 5 are connected to the bottom ring of the drill bit sleeve 3. The connecting sleeve 1, the supporting sleeve 2, and the drill bit sleeve 3 are connected from top to bottom by threads.

[0017] like Figure 1 As shown, the wall protection device mainly consists of three types of casings, all of which are hollow cylindrical casings. The connecting casing 1 has only one section, located at the top, and is used to connect with the drill rod. The drill rod drives the three types of casings to drill downwards. A top cover 4 is provided on the top of the connecting casing 1 to seal the top of the connecting casing 1, and a drill rod connecting device is provided on the upper surface of the top cover for detachable connection with the drill rod.

[0018] like Figure 5 As shown, the drill bit 5 is a diamond drill bit.

[0019] Several diamond drill bits 5 are connected to the circular surface at the bottom of the drill bit sleeve 3. When the diamond drill bits 5 are severely worn in the later stages, the diamond drill bits or the entire drill bit sleeve 3 can be replaced.

[0020] Driven by the drill rod, the diamond drill bit 5 drills a ring-shaped hole in the soil through the entire wall protection device. Since all three types of casings are hollow, only the casing wall is drilled open, while the inside of the casing remains the original soil.

[0021] The support casing 2 is connected between the connecting casing 1 and the drill bit casing 3, and finally remains in the soil to form a casing wall like a fence, which supports the surrounding soil and prevents the overburden layer from collapsing and shrinking during subsequent drilling.

[0022] There are several support sleeves 2, and the several support sleeves 2 are connected from top to bottom as one unit by threads.

[0023] Depending on the required drilling depth, a sufficient number of support sleeves can be selected and spliced ​​together to facilitate lengthening and connection, making it more applicable and eliminating the need to customize support sleeves of the required length according to the drilling depth.

[0024] like Figures 2 to 4As shown, the bottom of the connecting sleeve 1 is connected with an external thread, the top inner wall of the support sleeve 2 is opened with an internal thread, the bottom of the support sleeve 2 is connected with an external thread, the top inner wall of the drill bit sleeve 3 is opened with an internal thread, the external thread is inserted into the internal thread and matches the internal thread.

[0025] The connecting sleeve 1 is detachably connected to the drill rod via a drill rod connecting device.

[0026] The drill pipe connecting device is a drill bit connecting sleeve 6, and the inner wall of the drill bit connecting sleeve 6 has threads that match the drill bit.

[0027] All casings are interconnected by threads. The drill pipe connection device is a casing with threads on its inner wall that matches the threads on the bottom of the drill bit.

[0028] like Figure 1 As shown, a method for using a borehole wall protection device for consolidation grouting cover layer includes the following steps: The device is connected by connecting the connecting sleeve 1, the support sleeve 2, and the drill bit sleeve 3 from top to bottom through threads. The connecting sleeve is then connected to the bottom of the drill rod through the drill bit connecting sleeve 6. The wall protection device is drilled in, the drill rod is started, and the connecting casing 1, support casing 2 and drill bit casing 3 are drilled downward through the drill bit 5 at the bottom of the drill bit casing 3; In the drilling operation, the connecting sleeve 1 is separated from the drill rod and the supporting sleeve 2. The drill bit is connected to the drill rod and drills through the hollow part inside the supporting sleeve 2.

[0029] When the bottom of the connecting sleeve 1 is close to the ground, but the drill bit sleeve 3 has not yet reached the predetermined depth, the support sleeve 2 is replaced, the drill rod stops working, the connecting sleeve 1 is separated from the drill rod, the connecting sleeve 1 is separated from the lower support sleeve 2, a new support sleeve 2 is reconnected on the uppermost support sleeve 2, the drill rod, the connecting sleeve 1 and the newly added support sleeve 2 are reconnected, and drilling continues downward. This step is repeated until the drill bit sleeve 3 reaches the predetermined depth, at which point the support sleeve 2 is drilled in and remains in the soil.

[0030] During use, first connect the connecting sleeve 1, the support sleeve 2, and the drill bit sleeve 3 from top to bottom, and then connect the connecting sleeve 1 to the drill pipe. Drilling then begins, the drill rod starts, and the drill bit sleeve 3 moves downwards. Due to the limited length of the initial connecting sleeve 1, support sleeve 2, and drill bit sleeve 3, it is very likely that the connecting sleeve 1 is close to the ground, but the drill bit sleeve 3 has not yet reached the predetermined depth, that is, inside the bedrock layer. Furthermore, if the support sleeve 2 is set too long, then during installation, the height of the connecting sleeve 1, support sleeve 2, and drill bit sleeve 3 will exceed the height that the drill rod can lift, making it impossible to stand the connecting sleeve 1, support sleeve 2, and drill bit sleeve 3 upright.

[0031] Therefore, several shorter support sleeves 2 are spliced ​​together. Assuming that only one support sleeve 2 was used at the beginning, called support sleeve 2 No. 1, as the drilling goes down, most of support sleeve 2 No. 1 is buried in the soil, and only a small part is still above the ground, that is, the bottom of the connecting sleeve 1 is close to the ground. Separate the connecting sleeve 1 from the drill pipe, then separate the connecting sleeve 1 from the first support sleeve 2. Connect the second support sleeve 2 to the top of the first support sleeve 2. Connect the tops of the connecting sleeve 1 and the second support sleeve 2. Raise the drill pipe to a certain height and reconnect it with the connecting sleeve 1. Start the drill pipe to continue drilling. Repeat the installation of the third and fourth support sleeves 2 until the drill bit sleeve 3 hits the bedrock layer. The casing installation is then complete.

[0032] Then the connecting sleeve 1 is separated from the drill rod and separated from the uppermost supporting sleeve 2. All the supporting sleeves 2 and drill bit sleeves 3 are left in the soil to form a sleeve wall, which blocks the surrounding cover layer. Since all the sleeves are hollow, the inside of the sleeves is still soil.

[0033] The drill rod is connected to the drill bit, and drilling begins from the soil section in the middle of the casing. Since the drill bit and drill rod are supported by the walls of the casing 2 and the drill bit casing 3 on both sides, hole collapse and hole shrinkage will not occur.

Claims

1. A device for borehole wall protection in a consolidation grouting capping layer, characterized in that: It includes a connecting sleeve (1), a support sleeve (2) and a drill bit sleeve (3). The connecting sleeve (1), the support sleeve (2) and the drill bit sleeve (3) are all hollow cylindrical sleeves. The top of the connecting sleeve (1) is connected to a top cover (4), which seals the top of the connecting sleeve (1). A drill rod connecting device is connected to the upper surface of the top cover (4). Several drill bits (5) are connected to the bottom ring of the drill bit sleeve (3). The connecting sleeve (1), the support sleeve (2) and the drill bit sleeve (3) are connected from top to bottom by threads.

2. The device for borehole wall protection of a consolidation grouting cover layer according to claim 1, characterized in that: The drill bit (5) is a diamond drill bit.

3. The device for borehole wall protection of a consolidation grouting cover layer according to claim 1, characterized in that: There are several support sleeves (2), and several support sleeves (2) are connected from top to bottom as one unit by threads.

4. A borehole wall protection device for consolidation grouting cover layer according to claim 1 or 3, characterized in that: The bottom of the connecting sleeve (1) is connected with an external thread, the top inner wall of the support sleeve (2) is opened with an internal thread, the bottom of the support sleeve (2) is connected with an external thread, the top inner wall of the drill bit sleeve (3) is opened with an internal thread, the external thread is inserted into the internal thread and matches the internal thread.

5. The device for borehole wall protection of a consolidation grouting cover layer according to claim 1, characterized in that: The connecting sleeve (1) is detachably connected to the drill rod via the drill rod connecting device.

6. A borehole wall protection device for consolidation grouting cover layer according to claim 1 or 5, characterized in that: The drill pipe connecting device is a drill bit connecting sleeve (6), and the inner wall of the drill bit connecting sleeve (6) has threads that match the drill bit.

7. The method of using the consolidation grouting cover layer borehole wall protection device according to any one of claims 1-6, characterized in that: Includes the following steps, The device is connected by connecting the connecting sleeve (1), the support sleeve (2) and the drill bit sleeve (3) from top to bottom through threads, and connecting the connecting sleeve to the bottom of the drill rod through the drill bit connecting sleeve (6); The wall protection device is drilled in, the drill rod is started, and the connecting casing (1), support casing (2) and drill bit casing (3) are drilled downward through the drill bit (5) at the bottom of the drill bit casing (3); In the drilling operation, the connecting sleeve (1) is separated from the drill rod and the supporting sleeve (2), and the drill bit is connected to the drill rod. The drill bit drills through the hollow part inside the supporting sleeve (2).

8. The method of using the consolidation grouting cover layer borehole wall protection device according to claim 7, characterized in that: When the bottom of the connecting sleeve (1) is close to the ground, but the drill bit sleeve (3) has not yet reached the predetermined depth, the support sleeve (2) is replaced, the drill rod stops working, the connecting sleeve (1) is separated from the drill rod, the connecting sleeve (1) is separated from the lower support sleeve (2), a new support sleeve (2) is reconnected on the uppermost support sleeve (2), the drill rod, the connecting sleeve (1) and the newly added support sleeve (2) are reconnected, and drilling continues downward. This step is repeated until the drill bit sleeve (3) reaches the predetermined depth. At this time, the support sleeve (2) is drilled in and left in the soil.

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