A soil drill bit and a drilling machine for drilling a cast-in-place pile in a deep silt stratum

Abstract

The utility model discloses a kind of soil layer drill bits of deep thick silt stratum cast-in-place pile drilling, belong to drilling technical field, solve the problem of existing drill bit drilling quality not high.It includes earth drill and outer ring scraper, the earth drill includes drill bit body and multiple drill teeth, the drill bit body is detachably installed at the bottom of drill bit middle rod, multiple the drill teeth are evenly fixed in the outer wall of drill bit body;The outer ring scraper includes circular ring and multiple scrapes, the circular ring is detachably installed at the periphery of drill bit middle rod, multiple the scrapes are divided into two layers, and the scrapes of each layer are evenly fixed in the outer wall of circular ring, and the scrapes of upper and lower layers are staggered arrangement, and the outer diameter of circular ring is greater than the maximum diameter of drill bit body.The soil layer drill bit of the utility model can realize drilling and hole channel finishing compaction simultaneously, improve drilling quality.The utility model further discloses a kind of deep thick silt stratum cast-in-place pile drilling drilling machine, which can effectively improve construction efficiency.

Description

Technical Field

[0001] This utility model relates to the field of drilling technology, and more specifically, it relates to a soil drill bit and drilling machine for drilling cast-in-place piles in deep silt strata. Background Technology

[0002] The construction of cast-in-place piles in deep silt formations presents significant technical challenges. Firstly, the high sensitivity and low structural strength of silt result in extremely poor borehole stability; disturbance of the drill bit easily leads to necking or borehole collapse, directly affecting the quality of the hole. The drilling method for cast-in-place piles in deep silt formations involves using a rotary drill bit in conjunction with wall-forming mud, transmitting torque and pressure through the drill rod system to achieve drilling. Therefore, the drill bit is a crucial piece of equipment during construction. In practice, different materials or structures of drill bits are typically used for cutting and drilling in different formations to reduce the risk of drill bit damage and improve construction efficiency.

[0003] Existing drill bits for drilling cast-in-place piles, such as those with authorization announcement numbers: CN 212130403 U, CN

[0004] The drill bits disclosed in patents 208870534U and CN 214576767 U are typically conical in shape with a pointed bottom and a circular top. They utilize multiple teeth on the outer wall of the conical drill bit for rotary cutting, in conjunction with the axial feed of the drilling rig, to achieve drilling of cast-in-place piles in deep silt formations. However, existing drill bits only utilize the teeth on the outer wall of the conical drill bit for cutting. This lack of post-cutting finishing makes it difficult to refine the hole, easily leading to uneven hole walls. This unevenness is particularly prevalent in deep silt formations, severely impacting drilling quality.

[0005] Therefore, it is necessary to design a soil drill bit and drilling machine for drilling deep silt strata cast-in-place piles to solve the aforementioned technical problems. Utility Model Content

[0006] The technical problem to be solved by this utility model is to address the above-mentioned shortcomings of the existing technology. One of its objectives is to provide a soil drill bit for drilling deep silt strata cast-in-place piles, which can realize drilling and duct trimming and compaction at the same time, thereby improving the drilling quality.

[0007] The second objective is to provide a drilling machine for drilling cast-in-place piles in deep silt formations, thereby improving construction efficiency.

[0008] The technical solution of this utility model is as follows: A soil drill bit for drilling deep silt strata cast-in-place piles includes an entry drill bit and an outer ring scraper. The entry drill bit and the outer ring scraper are installed on the drill bit rod from bottom to top, and the entry drill bit and the outer ring scraper are arranged at intervals. The entry drill bit includes a drill bit body and multiple drill teeth. The drill bit body is detachably installed at the bottom of the drill bit rod, and the multiple drill teeth are evenly fixed on the outer wall of the drill bit body. The outer ring scraper includes a ring and multiple scraper blades. The ring is detachably installed on the periphery of the drill bit rod, and the multiple scraper blades are divided into upper and lower layers. Each layer of scraper blades is evenly fixed on the outer wall of the ring, and the upper and lower layers of scraper blades are staggered. The outer diameter of the ring is larger than the maximum diameter of the drill bit body.

[0009] As a further improvement, the drill bit body is a solid cone with a pointed bottom, a flat top, and an arc-shaped outer wall.

[0010] Furthermore, a threaded hole is provided at the center of the drill bit body, and a threaded post is provided at the bottom of the drill bit rod. The threaded post is threaded into the threaded hole, and a locking nut is threaded onto the threaded post. The locking nut is attached to the top surface of the drill bit body.

[0011] Furthermore, the outer wall of the ring and the outer wall of the scraper are both inclined structures that are larger at the top and smaller at the bottom.

[0012] Furthermore, a sleeve is provided inside the ring, and the sleeve is fixedly connected to the ring by multiple connecting rods. The sleeve is slidably sleeved on the drill bit rod, and each connecting rod is provided with a support structure between itself and the drill bit body.

[0013] Furthermore, the support structure includes a support rod, an upper support nut, and a lower support nut. One end of the support rod is fixed to the top of the drill bit body, and the other end slides through the connecting rod. The upper support nut and the lower support nut are threaded onto the support rods on the upper and lower sides of the connecting rod, respectively, and both the upper support nut and the lower support nut are in contact with the surface of the connecting rod.

[0014] Furthermore, the inner wall of the sleeve is rectangular, and correspondingly, the outer wall of the drill bit rod is rectangular.

[0015] Furthermore, the top of the upper scraper protrudes from the top of the ring, and the bottom of the lower scraper protrudes from the bottom of the ring.

[0016] Furthermore, the drill teeth are made of high-manganese alloy.

[0017] The second technical solution of this utility model is as follows: a drilling machine for drilling cast-in-place piles in deep silt strata, including the above-mentioned soil drill bit.

[0018] Beneficial effects

[0019] Compared with the prior art, this utility model has the following advantages:

[0020] 1. The soil drill bit of this utility model increases the stability of the drill bit during the drilling process by setting an outer ring scraper above the soil entry drill bit, which can effectively reduce hole collapse and deviation, and ensure construction quality. After the soil entry drill bit exits the hole, the outer ring scraper can trim and compact the hole wall, which can realize drilling and hole trimming and compaction at the same time, thus improving drilling quality.

[0021] 2. The soil drill bit of this utility model has an outer ring scraper that is slidably mounted on the drill bit rod and supported and fixed by a support structure. The position of the outer ring scraper can be adjusted according to actual needs to ensure the stability of the drill bit during drilling. The soil entry drill bit and the drill bit rod are connected by threads and tightened by a locking nut. By loosening the locking nut and the corresponding support nut of the support structure, the outer ring scraper can be lifted up and detached from the support rod of the support structure. Then, the soil entry drill bit can be rotated to disassemble it. Then, the outer ring scraper can be pulled out along the axial direction of the drill bit rod. This makes the disassembly and maintenance of the soil entry drill bit and the outer ring scraper very convenient. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the main structure of this utility model;

[0023] Figure 2 This is a top view of the structure of this utility model;

[0024] Figure 3 This is a schematic diagram of the front cross-sectional structure of this utility model.

[0025] The components are: 1. Soil-penetrating drill bit; 2. Outer ring scraper; 3. Drill bit rod; 4. Locking nut; 5. Sleeve; 6. Connecting rod; 7. Support rod; 8. Upper support nut; 9. Lower support nut; 101. Drill bit body; 102. Drill teeth; 201. Circular ring; 202. Scraper blade. Detailed Implementation

[0026] The present invention will be further described below with reference to specific embodiments shown in the accompanying drawings.

[0027] See Figure 1-3This utility model discloses a soil drilling bit for drilling deep silt strata for cast-in-place piles, specifically designed for cutting and drilling deep silt strata. The soil drilling bit includes a soil-penetrating drill bit 1 and an outer ring scraper 2. The soil-penetrating drill bit 1 and the outer ring scraper 2 are mounted from bottom to top on the drill bit shaft 3. The soil-penetrating drill bit 1 serves as the main cutting tool, while the outer ring scraper 2 is used to trim and compact the hole wall. The soil-penetrating drill bit 1 and the outer ring scraper 2 are spaced apart to facilitate the removal of debris after cutting by the soil-penetrating drill bit 1. The soil-penetrating drill bit 1 includes a drill body 101 and multiple drill teeth 102. The drill teeth 102 are tapered cutting teeth with a rake angle controlled within the range of 25°-30° and a tooth height of 80-100mm. The drill body 101 is detachably mounted at the bottom of the drill bit shaft 3 for easy soil penetration. The head 1 is disassembled for maintenance. Multiple drill teeth 102 are evenly fixed on the outer wall of the drill bit body 101 to ensure the cutting performance of the drill bit for soil penetration. The outer ring scraper 2 includes a ring 201 and multiple scraper blades 202. The ring 201 is detachably installed on the periphery of the drill bit rod 3, making it easy to disassemble the outer ring scraper 2 for maintenance. The multiple scraper blades 202 are divided into upper and lower layers. Each layer of scraper blades 202 is evenly fixed on the outer wall of the ring 201, and the upper and lower layers of scraper blades 202 are staggered to achieve multiple scraping and finishing of the hole wall. The outer diameter of the ring 201 is larger than the maximum diameter of the drill bit body 101 to ensure that the outer ring scraper 2 can contact the hole wall.

[0028] This utility model of a soil drilling bit, by setting an outer ring scraper 2 above the soil entry drill bit 1, simultaneously scrapes the hole wall, providing radial support above the soil entry drill bit 1, increasing the stability of the drill bit during drilling, effectively reducing hole collapse and off-center drilling, and ensuring construction quality. After the soil entry drill bit 1 drills out of the hole, the outer ring scraper 2 can trim and compact the hole wall, enabling drilling and hole trimming and compaction to be carried out simultaneously, thus improving drilling quality.

[0029] Preferably, the drill bit body 101 is a solid cone with a pointed bottom, a flat top, and an arc-shaped outer wall. In this embodiment of the soil drill bit, the drill bit body 101 adopts a solid cone with a pointed bottom, which can effectively utilize the weight of the drill bit body 101 for axial feed, reducing the pressure applied to the soil-penetrating drill bit 1 by the drilling machine, thereby reducing the load on the drilling machine. It should be noted that this embodiment of the soil drill bit is designed for soil cutting drilling; however, for rock formations, a solid cone drill bit body structure is not suitable.

[0030] Preferably, a threaded hole is provided at the center of the drill bit body 101, and a threaded post is provided at the bottom of the drill bit rod 3. The diameter of the threaded post is smaller than the width of the drill bit rod 3. The threaded post is threaded into the threaded hole, and a lock nut 4 is threaded onto the threaded post. The lock nut 4 fits against the top surface of the drill bit body 101. After the threaded post is threaded into the drill bit body 101, it is tightened by the lock nut 4 to prevent the drill bit body 101 from loosening, and also to facilitate disassembly and maintenance.

[0031] Preferably, the outer wall of the ring 201 and the outer wall of the scraper 202 are both inclined structures with a larger upper surface and a smaller lower surface, which facilitates the axial feeding of the outer ring scraper 2.

[0032] Preferably, a sleeve 5 is provided inside the ring 201. The sleeve 5 is fixedly connected to the ring 201 by multiple connecting rods 6, forming a hollow frame structure to facilitate the discharge of debris. The sleeve 5 is slidably fitted onto the drill bit rod 3, and each connecting rod 6 is provided with a support structure between itself and the drill bit body 101. This allows for both the fixed installation of the outer ring scraper 2 and convenient disassembly and maintenance. Specifically, the support structure includes a support rod 7, an upper support nut 8, and a lower support nut 9. One end of the support rod 7 is fixed to the top of the drill bit body 101, and the other end slides through the connecting rod 6. The upper support nut 8 and the lower support nut 9 are threaded onto the support rod 7 on the upper and lower sides of the connecting rod 6, respectively, and both the upper support nut 8 and the lower support nut 9 are in contact with the surface of the connecting rod 6. This fixes the outer ring scraper 2 onto the drill bit rod 3 above the soil-penetrating drill bit 1, and also allows for height adjustment of the outer ring scraper 2.

[0033] In this embodiment, the outer ring scraper 2 of the soil drill bit is slidably mounted on the drill bit rod 3 and supported and fixed by a support structure. According to actual needs, the upper support nut 8 and the lower support nut 9 can be loosened to adjust the position of the outer ring scraper 2 to ensure the stability of the drill bit during drilling. At the same time, the soil entry drill bit 1 and the drill bit rod 3 are connected by threads and tightened by locking nut 4. By loosening the locking nut 4 and the corresponding support nut of the support structure, the outer ring scraper 2 can be lifted up and disengaged from the corresponding support rod 7 of the support structure. Then, the soil entry drill bit 1 can be rotated to disassemble it. Then, the outer ring scraper 2 can be pulled out along the axial direction of the drill bit rod 3. This makes the disassembly and maintenance of the soil entry drill bit 1 and the outer ring scraper 2 very convenient.

[0034] Preferably, the inner wall of the sleeve 5 is rectangular, and correspondingly, the outer wall of the drill bit rod 3 is rectangular. The sleeve 5 and the drill bit rod 3 adopt a rectangular circumferential limiting structure, which can further prevent the outer ring scraper 2 from rotating relative to the drill bit rod 3 and reduce the load on the support structure.

[0035] Preferably, the top of the upper scraper 202 protrudes from the top of the ring 201, and the bottom of the lower scraper 202 protrudes from the bottom of the ring 201, which effectively increases the axial scraping area of ​​the scraper 202 and further improves the quality of hole wall finishing and compaction.

[0036] Preferably, the drill bit 102 is made of high manganese alloy, which can effectively improve the structural strength of the drill bit 102 and extend its service life.

[0037] A drilling machine for drilling cast-in-place piles in deep silt strata includes the aforementioned soil drill bit, wherein the drill bit rod 3 of the soil drill bit is connected to the output end of the feed system of the drilling machine by means of bolts, flanges or pins, etc., to realize the drilling of cast-in-place piles and effectively improve construction efficiency.

[0038] When the soil drill bit and drilling machine of this embodiment are used in construction in deep silt strata:

[0039] Slurry preparation: High-quality sodium-based bentonite (ratio 90-120 kg / m³) is used. 3 Add 0.8-1.2 kg / m³ 3 PAC thickener, controlling the mud specific gravity to 1.20-1.30 g / cm³ 3 With a viscosity of 25-30s and a sand content of <6%, the solution is stirred at high speed for 40 minutes and then allowed to stand for 36 hours to hydrate. During construction, the viscosity is dynamically adjusted to 28-32s according to the characteristics of the drill bit, and the circulation flow rate is controlled at 1.0-1.5m³. 3 / min. Its single-ring soil drill bit with drill teeth, combined with mud drilling, can effectively ensure the drill bit's drilling and wall protection capabilities in silt and coarse sand formations, greatly improving the accuracy and efficiency of drilling.

[0040] Drilling rig commissioning parameters: For its single-ring soil drill bit with drill teeth, to ensure construction quality and efficiency, the matching and adjustment of rotation speed and mechanical power should be the focus during commissioning. To verify the most suitable parameters for the drill bit improvement, five test piles were used before construction. The table below compares the main performance parameters before and after the improvement in detail:

[0041] Comparison table of test pile results

[0042]

[0043]

[0044] The test pile results show that using a drill bit with a single ring and tapered cutting teeth can effectively reduce the filling coefficient, the grouting inclination, and the motor power of the cast-in-place pile. Under the same drill bit conditions, reducing the rotational speed can effectively reduce power consumption and the filling coefficient.

[0045] During actual construction and commissioning, the rotation speed should be adjusted gradually, initially controlled at 25-30 r / m, and gradually increased to 35 r / m after the equipment is running stably. If it is difficult to drill through coarse sandy strata, the rotation speed should be increased but the drilling speed should be reduced. During construction, close attention should be paid to the drilling speed and power meter to ensure that the equipment operates under the best conditions. After every 5 pile holes are completed, the wear of the cutting teeth and the outer ring cutter of the drill bit can be checked to ensure that they continue to maintain good working performance.

[0046] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several modifications and improvements can be made without departing from the structure of the present utility model. These modifications and improvements will not affect the effectiveness of the present utility model or the practicality of the patent.

Claims

1. A soil drill bit for drilling cast-in-place piles in deep silt strata, characterized in that, The system includes a soil-penetrating drill bit (1) and an outer ring scraper (2). The soil-penetrating drill bit (1) and the outer ring scraper (2) are mounted on the drill bit rod (3) from bottom to top, and the soil-penetrating drill bit (1) and the outer ring scraper (2) are arranged at intervals. The soil-penetrating drill bit (1) includes a drill bit body (101) and a plurality of drill teeth (102). The drill bit body (101) is detachably mounted on the bottom of the drill bit rod (3), and the plurality of drill teeth (102) are evenly fixed on the drill bit body (101). 1) The outer wall; the outer ring scraper (2) includes a ring (201) and multiple scraper blades (202). The ring (201) is detachably installed on the periphery of the drill rod (3). The multiple scraper blades (202) are divided into upper and lower layers. Each layer of scraper blades (202) is evenly fixed on the outer wall of the ring (201), and the upper and lower layers of scraper blades (202) are staggered. The outer diameter of the ring (201) is greater than the maximum diameter of the drill body (101).

2. The soil drill bit for drilling deep silt strata cast-in-place piles according to claim 1, characterized in that, The drill bit body (101) is a solid cone with a pointed bottom, a flat top, and an arc-shaped outer wall.

3. The soil drill bit for drilling deep silt strata cast-in-place piles according to claim 2, characterized in that, The drill bit body (101) has a threaded hole at its center, and the bottom of the drill bit rod (3) has a threaded post. The threaded post is threaded into the threaded hole, and a locking nut (4) is threaded onto the threaded post. The locking nut (4) is attached to the top surface of the drill bit body (101).

4. The soil drill bit for drilling deep silt strata cast-in-place piles according to claim 1, characterized in that, The outer walls of the ring (201) and the scraper (202) are both inclined structures with a larger upper surface and a smaller lower surface.

5. The soil drill bit for drilling deep silt strata cast-in-place piles according to claim 1, characterized in that, The ring (201) is provided with a sleeve (5), and the sleeve (5) is fixedly connected to the ring (201) by multiple connecting rods (6). The sleeve (5) is slidably sleeved on the drill rod (3), and each connecting rod (6) is provided with a support structure between itself and the drill body (101).

6. The soil drill bit for drilling deep silt strata cast-in-place piles according to claim 5, characterized in that, The support structure includes a support rod (7), an upper support nut (8), and a lower support nut (9). One end of the support rod (7) is fixed to the top of the drill bit body (101), and the other end slides through the connecting rod (6). The upper support nut (8) and the lower support nut (9) are threadedly connected to the support rod (7) on the upper and lower sides of the connecting rod (6), respectively, and the upper support nut (8) and the lower support nut (9) are both attached to the surface of the connecting rod (6).

7. A soil drill bit for drilling deep silt strata cast-in-place piles according to claim 5, characterized in that, The inner wall of the sleeve (5) is rectangular, and correspondingly, the outer wall of the drill rod (3) is rectangular.

8. The soil drill bit for drilling deep silt strata cast-in-place piles according to claim 1, characterized in that, The top of the upper scraper (202) protrudes from the top of the ring (201), and the bottom of the lower scraper (202) protrudes from the bottom of the ring (201).

9. A soil drill bit for drilling deep silt strata cast-in-place piles according to claim 1, characterized in that, The drill bit (102) is made of high manganese alloy.

10. A drilling machine for drilling cast-in-place piles in deep silt strata, characterized in that, The soil drill bit includes any one of claims 1-9.

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