Anti-necking device for soft soil foundation variable-diameter drill bit

Abstract

The utility model relates to a kind of soft soil foundation variable-diameter drill bit necking-preventing devices applied to drilling device field, drill string drilling is automatically paused after setting meter number in the present scheme, intelligent detection component starts operation immediately, in the vertical hollow cavity of middle column, electric push rod pushes vertical linkage push rod, so that high-strength soil breaking probe is pierced into soil layer through through-hole, by its integrated miniature soil pressure sensor, moisture content sensor and soil hardness gauge, key parameters are synchronously collected and transmitted to control terminal, when soft soil, the hydraulic rod telescopic column of instruction variable-diameter drill bit component extends, through load solid ring and U type side ear block, variable-diameter V type drill rod is pushed open, conical convex block cuts hole wall and expands diameter, accurately offsets soft soil retraction, when hard soil, drill rod is kept to fold, maintain round hole drilling, this dynamic adjustment mechanism can adapt to complex soil layer change, realize the automation and intelligentization of soft soil foundation drilling necking-preventing.

Description

Technical Field

[0001] This utility model relates to a drill bit anti-neck device, and more particularly to a soft soil foundation variable diameter drill bit anti-neck device applied in the field of drilling equipment. Background Technology

[0002] A variable diameter drill bit is a specialized drilling tool that can dynamically adjust the borehole diameter according to construction needs. It is widely used in foundation engineering, underground pipeline laying and other fields, and is especially suitable for soft soil foundations and other scenarios that require flexible adaptation to different soil layer characteristics.

[0003] Chinese patent CN201874473U discloses a cross-diameter drill bit. This drill bit has a cylindrical sliding shaft with a sliding sleeve that can slide up and down. An adjusting rod is fixed to the sliding sleeve. The lower end of a plate-shaped drill bit is hinged to the lower end of the sliding shaft, and the upper end of the drill bit is sequentially hinged to the adjusting rod and both sides of the sliding sleeve. Users can change the diameter of the drill bit as needed, making it convenient and practical.

[0004] Chinese patent CCN214196191U discloses a variable-diameter drill bit, including a drill rod with a movable chamber inside. A first spring is fixedly connected to the bottom of the inner wall of the movable chamber, and a connecting block is fixedly connected to the bottom of the first spring. The connecting block is slidably disposed in the movable chamber, and a drill bit is fixedly connected to the bottom of the connecting block. Multiple first limiting blocks are fixedly connected to the drill bit. By using the connecting blocks, the drill bit can retract when it encounters rocks or other objects during drilling, causing the reaming rod to move outward, thereby increasing the diameter of the drill hole and preventing the drill bit from getting stuck. Forcibly pulling it out can easily damage the drill bit, rendering it unusable and affecting the construction progress.

[0005] Existing necking prevention devices for variable-diameter drill bits rely on manual experience to judge soil properties, which cannot identify soft soil sections in real time during drilling. Often, necking is discovered too late, leading to rework, requiring secondary hole enlargement or removal and re-drilling. This not only increases the construction period and cost, but also exacerbates the damage to the soft soil structure due to repeated disturbance. Utility Model Content

[0006] The technical problem that this utility model aims to solve in response to the above-mentioned prior art is that existing anti-neck devices for variable diameter drill bits rely on manual experience to judge the properties of soil layers, and cannot identify soft soil sections in real time during drilling. As a result, rework is often required due to the late detection of necking, which necessitates secondary hole enlargement or removal and re-drilling. This not only increases the construction period and cost, but also exacerbates the damage to the soft soil structure due to repeated disturbances.

[0007] To address the aforementioned problems, this utility model provides a necking prevention device for a variable-diameter drill bit in soft soil foundations. The device includes a drilling assembly, a variable-diameter drill bit assembly at its lower end, an intelligent detection assembly within the variable-diameter drill bit assembly, and a soil removal assembly within the intelligent detection assembly. The drilling assembly includes a drill string, with a main drill bit mounted at its lower end. The variable-diameter drill bit assembly includes a hydraulic rod fixing column fixedly connected between the drill string and the main drill bit. A hydraulic rod telescopic column is slidably connected to the lower end of the hydraulic rod fixing column, and the hydraulic rod fixing column and the hydraulic rod telescopic column are spaced apart from each other. One end of each component is fixedly connected to a load-bearing ring. The outer end of the load-bearing ring is fixedly connected to multiple U-shaped side lugs. A pair of variable-diameter V-shaped drill rods are rotatably connected between the upper and lower corresponding U-shaped side lugs. The intelligent detection component includes a central column fixedly connected to the outside of the hydraulic rod fixing column. Multiple vertical hollow cavities are opened at the outer end of the central column. An electric push rod is fixedly connected to the inner wall of the vertical hollow cavity. A vertical linkage push rod is installed at the output end of the electric push rod. Multiple high-strength soil-breaking probes are fixedly connected to the end of the vertical linkage push rod away from the central column.

[0008] In the aforementioned anti-neck device for variable-diameter drill bits in soft soil foundations, this solution adopts a dynamic adjustment mechanism that can adapt to complex soil layer changes, ensuring that the borehole diameter always meets the design requirements, greatly improving construction quality, and realizing the automation and intelligence of anti-neck drilling in soft soil foundations.

[0009] As a further improvement of this application, multiple vertical hollow cavities and multiple variable-diameter V-shaped drill rods are spaced apart, and the soil removal assembly includes an external vertical plate fixedly connected to the opening of the vertical hollow cavity.

[0010] As a further improvement of this application, the outer side of the external upright plate is provided with multiple through holes that cooperate with the high-strength soil-breaking probe, and the inner sidewall of the through holes is fixedly connected with an inner convex auxiliary metal cylinder.

[0011] As a further improvement of this application, multiple springs are fixedly connected to the inner wall of the convex auxiliary metal cylinder, and a strong electromagnetic arc strip is fixedly connected to the end of each spring away from the convex auxiliary metal cylinder.

[0012] As another improvement of this application, the end of the strong electromagnetic arc strip away from the spring is fixedly connected to an inner convex soil scraping bar, and the inner convex soil scraping bar and the outer wall of the high-strength soil breaking probe are in contact with each other.

[0013] As a further improvement to this application, the end of the variable-diameter V-type drill pipe away from the hydraulic rod telescopic column is fixedly connected to a plurality of equally spaced conical protrusions, and the drilling assembly is externally connected to a control terminal.

[0014] As a further improvement to this application, the multiple high-strength soil-breaking probes of the vertical linkage push rod are a miniature earth pressure sensor, a moisture content sensor, and a soil hardness tester.

[0015] In summary, this solution automatically pauses drilling after the drill string reaches the set depth, and the intelligent detection component immediately starts operation. Inside the vertical hollow cavity of the central column, an electric actuator pushes a vertical linkage actuator, causing a high-strength soil-breaking probe to penetrate the soil layer through the through-hole. Utilizing its integrated micro earth pressure sensor, moisture sensor, and soil hardness gauge, it simultaneously collects key parameters and transmits them to the control terminal. When encountering soft soil, the hydraulic rod extension column of the variable-diameter drill bit assembly is extended, pushing the variable-diameter V-shaped drill rod open through the load-bearing retaining ring and U-shaped side lugs. The conical protrusion cuts the hole wall, expanding the diameter and precisely counteracting the shrinkage of soft soil. When encountering hard soil, the drill rod remains retracted, maintaining the circular hole drilling. This dynamic adjustment mechanism can adapt to complex soil layer changes, ensuring that the borehole diameter always meets design requirements, significantly improving construction quality, and achieving automation and intelligence in preventing necking during drilling in soft soil foundations. Attached Figure Description

[0016] Figure 1 This is an isometric view of the drilling assembly according to the first embodiment of this application;

[0017] Figure 2 This is an enlarged structural view of a partial truncated section of the drill string according to the first embodiment of this application;

[0018] Figure 3 This is a top view of the drill string structure according to the first embodiment of this application;

[0019] Figure 4 This is a structural diagram of the intelligent detection component according to the first and second embodiments of this application;

[0020] Figure 5 This is a structural diagram of the variable diameter drill bit assembly according to the first embodiment of this application;

[0021] Figure 6 This is a structural diagram of the soil removal component according to the second embodiment of this application;

[0022] Figure 7 This is a structural diagram of the inner convex auxiliary metal cylinder according to the second embodiment of this application.

[0023] Explanation of the labels in the diagram:

[0024] 1. Drilling assembly; 100. Drill string; 101. Main drill bit; 2. Variable diameter drill bit assembly; 200. Hydraulic rod fixing column; 201. Hydraulic rod telescopic column; 202. Load-bearing retaining ring; 203. U-shaped side lug block; 204. Variable diameter V-shaped drill rod; 205. Conical protrusion block; 3. Intelligent detection assembly; 301. Central column; 302. Vertical hollow cavity; 303. Electrical push rod; 304. Vertical linkage push rod; 305. High-strength soil breaking probe; 4. Soil removal assembly; 400. External upright plate; 401. Through hole; 402. Inwardly protruding auxiliary metal cylinder; 403. Spring; 404. Strong electromagnetic arc strip; 405. Inwardly protruding soil scraping bar. Detailed Implementation

[0025] The two embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0026] First implementation method:

[0027] Figures 1-5 This invention discloses a necking prevention device for a variable-diameter drill bit in soft soil foundations, comprising a drilling assembly 1, a variable-diameter drill bit assembly 2 at the lower end of the drilling assembly 1, an intelligent detection assembly 3 in cooperation with the variable-diameter drill bit assembly 2, and a soil removal assembly 4 in the intelligent detection assembly 3. The drilling assembly 1 includes a drill string 100, with a main drill bit 101 mounted at the lower end of the drill string 100. The variable-diameter drill bit assembly 2 includes a hydraulic rod fixing column 200 fixedly connected between the drill string 100 and the main drill bit 101. A hydraulic rod telescopic column 201 is slidably connected to the lower end of the hydraulic rod fixing column 200. A load-bearing retaining ring 202 is fixedly connected to the ends of both the hydraulic rod fixing column 200 and the hydraulic rod telescopic column 201 that are far apart from each other. Multiple U-shaped side lugs 203 are fixedly connected to the outer end of the device. A pair of variable-diameter V-shaped drill rods 204 are rotatably connected between the upper and lower corresponding U-shaped side lugs 203. The intelligent detection component 3 includes a central column 301 fixedly connected to the outside of the hydraulic rod fixing column 200. Multiple vertical hollow cavities 302 are opened at the outer end of the central column 301. An electric push rod 303 is fixedly connected to the inner wall of the vertical hollow cavity 302. A TOLOMATICEA-05 miniature electric push rod can be used. A vertical linkage push rod 304 is installed at the output end of the electric push rod 303. Multiple high-strength soil-breaking probes 305 are fixedly connected to the end of the vertical linkage push rod 304 away from the central column 301.

[0028] Multiple vertical hollow cavities 302 and multiple variable-diameter V-shaped drill rods 204 are spaced apart. Multiple equidistant conical protrusions 205 are fixedly connected to the end of the variable-diameter V-shaped drill rod 204 away from the hydraulic rod telescopic column 201. The drilling assembly 1 is externally connected to a control terminal, which can be a PLC S7-1200 series controller. The multiple high-strength soil-breaking probes 305 of the vertical linkage push rod 304 are micro earth pressure sensors, which can be BNC815 series biaxial pressure sensors, moisture content sensors, FDR-100 high-frequency capacitive sensors, soil hardness testers, or ST-1 type micro hardness sensors.

[0029] Figures 1-5 This scheme demonstrates that the main drill bit 101 at the lower end of the drill string 100 rotates and drills to form the initial borehole. At this time, the variable diameter drill bit assembly 2 is in a retracted state, the hydraulic rod telescopic column 201 retracts into the hydraulic rod fixed column 200, and the upper and lower load-bearing rings 202 drive the variable diameter V-shaped drill rod 204 to retract through the U-shaped side lugs 203 to avoid interfering with the initial borehole. During the drilling process, a preset pause time limit is set, which can pause after drilling a set number of meters, and the intelligent detection component 3 starts the detection program. The electric push rod 303 in the vertical hollow cavity 302 outside the middle column 301 extends, pushing the vertical linkage push rod 304 to extend outward, so that multiple high-strength soil-breaking probes 305 pass through the through hole 401 of the soil-removing component 4 and penetrate into the soil layer of the borehole wall. Since the high-strength soil-breaking probes 305 are micro Earth pressure sensors, moisture content sensors, and soil hardness testers can simultaneously collect data on soil shrinkage force, moisture content, and hardness, and transmit the signals to an external control terminal. The control terminal determines the soil properties based on the detection data. If it is soft soil with high moisture content, low hardness, and high shrinkage force, it immediately instructs the variable diameter drill bit assembly 2 to operate. The hydraulic rod telescopic column 201 extends downward, pushing the variable diameter V-shaped drill rod 204 outward through the load-bearing retaining ring 202 and U-shaped side lug 203. The conical protrusion 205 at its end cuts the hole wall, expanding the borehole diameter to counteract the shrinkage of the soft soil. If it is hard soil, the variable diameter V-shaped drill rod 204 remains in a contracted state, maintaining the initial circular hole drilling. The above process is repeated cyclically to effectively ensure that the borehole diameter in soft soil layers always meets the design requirements and effectively prevents necking.

[0030] The second implementation method,

[0031] Figure 4 , Figures 6-7This invention illustrates a necking prevention device for a variable-diameter drill bit in soft soil foundations. The soil-removing component 4 includes an outer vertical plate 400 fixedly connected to the opening of a vertical hollow cavity 302. Multiple through-holes 401, which cooperate with a high-strength soil-breaking probe 305, are opened on the outer side of the outer vertical plate 400. An inner convex auxiliary metal cylinder 402 is fixedly connected to the inner wall of the through-holes 401. Multiple springs 403 are fixedly connected to the inner wall of the inner convex auxiliary metal cylinder 402. A strong electromagnetic arc strip 404 is fixedly connected to the end of each spring 403 away from the inner convex auxiliary metal cylinder 402. An inner convex soil scraper is fixedly connected to the end of the strong electromagnetic arc strip 404 away from the spring 403. The inner convex scraping rib 405 and the outer wall of the high-strength soil-breaking probe 305 come into contact with each other. After the test is completed, the electric push rod 303 drives the vertical linkage push rod 304 to retract, and the high-strength soil-breaking probe 305 is pulled out of the soil layer. At this time, the soil removal component 4 works synchronously. The inner convex auxiliary metal cylinder 402 on the inner side of the outer vertical plate 400 pushes the strong electromagnetic arc strip 404 to tighten through the spring 403, so that the inner convex scraping rib 405 fits tightly against the outer wall of the high-strength soil-breaking probe 305. During the retraction of the high-strength soil-breaking probe 305, the attached soil is scraped off to avoid affecting the accuracy of the next test, reduce the manual cleaning process, and improve the continuous operation capability of the equipment.

[0032] In light of current practical needs, the above-described embodiments adopted in this application are not limited to these. Any changes made within the scope of knowledge possessed by those skilled in the art without departing from the concept of this application still fall within the protection scope of this utility model.

Claims

1. A necking prevention device for variable diameter drill bits in soft soil foundations, characterized in that: The system includes a drilling assembly (1), a variable diameter drill bit assembly (2) at the lower end of the drilling assembly (1), an intelligent detection assembly (3) in cooperation with the variable diameter drill bit assembly (2), a soil removal assembly (4) in the intelligent detection assembly (3), a drill string (100) at the lower end of the drill string (100), a main drill bit (101) installed thereon, and a hydraulic rod fixing column (200) fixedly connected between the drill string (100) and the main drill bit (101). A hydraulic rod telescopic column (201) is slidably connected to the lower end of the hydraulic rod fixing column (200). A load-bearing retaining ring (202) is fixedly connected to the ends of the hydraulic rod fixing column (200) and the hydraulic rod telescopic column (201) that are far apart from each other. The outer end of the load-bearing ring (202) is fixedly connected to a plurality of U-shaped side lugs (203), and a pair of variable diameter V-shaped drill rods (204) are rotatably connected between the upper and lower corresponding U-shaped side lugs (203). The intelligent detection component (3) includes a central column (301) fixedly connected to the outside of the hydraulic rod fixing column (200). The outer end of the central column (301) is provided with a plurality of vertical hollow cavities (302). The inner wall of the vertical hollow cavity (302) is fixedly connected to an electric push rod (303). The output end of the electric push rod (303) is equipped with a vertical linkage push rod (304). The end of the vertical linkage push rod (304) away from the central column (301) is fixedly connected to a plurality of vertically equidistant high-strength soil-breaking probes (305).

2. The anti-neck device for a variable-diameter drill bit in soft soil foundation according to claim 1, characterized in that: The plurality of vertical hollow cavities (302) and the plurality of variable diameter V-shaped drill rods (204) are spaced apart, and the soil removal assembly (4) includes an outer vertical plate (400) fixedly connected to the opening of the vertical hollow cavity (302).

3. The anti-neck device for a variable-diameter drill bit in soft soil foundation according to claim 2, characterized in that: The outer side of the external upright plate (400) is provided with a plurality of through holes (401) that cooperate with the high-strength soil-breaking probe (305), and the inner sidewall of the through holes (401) is fixedly connected with an inner convex auxiliary metal cylinder (402).

4. The anti-neck device for a variable-diameter drill bit in soft soil foundation according to claim 3, characterized in that: Multiple springs (403) are fixedly connected to the inner sidewall of the inner convex auxiliary metal cylinder (402), and a strong electromagnetic arc strip (404) is fixedly connected to the end of the corresponding multiple springs (403) away from the inner convex auxiliary metal cylinder (402).

5. The anti-neck device for a variable-diameter drill bit in soft soil foundation according to claim 4, characterized in that: The end of the strong electromagnetic arc strip (404) away from the spring (403) is fixedly connected to an inner convex soil scraping bar (405), and the inner convex soil scraping bar (405) and the outer wall of the high-strength soil breaking probe (305) are in contact with each other.

6. The anti-neck device for a variable-diameter drill bit in soft soil foundation according to claim 5, characterized in that: The variable-diameter V-shaped drill rod (204) has a plurality of equally spaced conical protrusions (205) fixedly connected to one end away from the hydraulic rod telescopic column (201), and the drilling assembly (1) is externally connected to a control terminal.

7. The anti-neck device for a variable-diameter drill bit in soft soil foundation according to claim 1, characterized in that: The multiple high-strength soil-breaking probes (305) of the vertical linkage push rod (304) are respectively a micro earth pressure sensor, a moisture content sensor, and a soil hardness meter.

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