A drilling device for drilling a cast-in-place pile hole

Abstract

This invention relates to the field of pile drilling rig technology, specifically to a drilling device for drilling and grouting pile holes. It includes a main mast with a sliding assembly on it. A power head is fixedly mounted on the sliding assembly, and a mechanically locked drill rod is sleeved inside the power head. The upper end of the mechanically locked drill rod is rotatably connected to the sliding assembly. By using a stirring plate inside the drill bucket, combined with water injection through the inlet pipe and pumping out mud and water, solid soil is collected and continuously pumped out as mud and water, maintaining an effective volume in the drill bucket. This allows for continuous drilling without frequent lifting and unloading of soil, significantly improving construction efficiency. Simultaneously, the negative pressure environment created by pumping water helps stabilize the borehole wall and reduces the risk of borehole collapse. Furthermore, this invention employs a dual anti-rotation mechanism—ground locking and underground rollers pressing against the well wall—to ensure that the pipeline remains statically arranged throughout the entire depth range, fundamentally preventing entanglement accidents and guaranteeing operational continuity and safety.

Description

Technical Field

[0001] This invention relates to the field of pile hole drilling technology, specifically to a drilling device for drilling and grouting pile holes. Background Technology

[0002] In cast-in-place pile construction, rotary drilling rigs are commonly used drilling equipment. They use a power head to rotate the mechanically locked drill rod, driving the drill bucket to cut through the soil and rock. The bottom of the drill bucket has cutting teeth and a feed hole. The rotating cutting action forces the excavated soil into the drill bucket. Once the bucket is full, the drill bit must be pulled up to the surface to unload the soil, and then the drill bit is lowered back down to continue operation. This intermittent operation mode results in a significant amount of time being spent on pulling up the drill bit, unloading the soil, and lowering the drill bit again, with auxiliary operations accounting for a large proportion of the time, severely restricting construction efficiency. This problem is particularly prominent in water-rich strata, sandy layers, and weathered rock layers, where the excavated soil has high water content and high viscosity, making unloading the drill bit difficult and necessitating frequent pulling up and unloading.

[0003] To address the aforementioned issues, some existing technologies attempt to incorporate water injection channels into the drill bit to wet the slag and reduce its viscosity, or to install slurry discharge pipes to extract the mud. However, these solutions face the significant problem of pipes twisting and tangling as the drill bit rotates. The water injection and slurry discharge pipes are highly susceptible to entanglement and even breakage during drill rod rotation, severely impacting equipment operation and safety. Currently, there is no effective method to ensure the stability and safety of the pipeline layout throughout the entire drilling process while achieving continuous slag discharge. Therefore, it is necessary to propose a drilling device for bored pile holes. Summary of the Invention

[0004] To address the problems in the prior art, the present invention provides a drilling device for bored pile holes.

[0005] The technical solution adopted by the present invention to solve its technical problem is: a drilling device for bored pile holes, including a main mast, a sliding assembly on the main mast, a power head fixedly installed on the sliding assembly, a mechanically locked drill rod sleeved inside the power head, the upper end of the mechanically locked drill rod being rotatably connected to the sliding assembly, a gooseneck assembly for assisting the lifting and lowering of the sliding assembly being provided at the top of the main mast, the sliding assembly for limiting the vertical lifting and lowering path of the power head and the mechanically locked drill rod, an elastic assembly for buffering being provided at the lower end of the mechanically locked drill rod, a fixed cylinder being sleeved at the lower end of the elastic assembly, the elastic assembly and the fixed cylinder being fixedly connected by a bolt assembly, and a drill bucket assembly being fixedly installed on the fixed cylinder; A rotating cylinder is rotatably connected to the outer wall of the fixed cylinder. Two second connecting rods are fixedly installed on the outer wall of the rotating cylinder. A baffle cylinder is fixedly installed on both second connecting rods. Two limiting holes are opened on the baffle cylinder. A cylinder is fixedly installed on the rotating cylinder. A U-shaped mounting bracket is fixedly installed at the output end of the cylinder. A limiting roller is rotatably connected inside the U-shaped mounting bracket. A mounting seat is sleeved on each of the two second connecting rods. A rectangular hole is opened through the mounting seat. The mounting seat is slidably connected to the second connecting rod through the rectangular hole. A mounting hole is opened on the mounting seat. A through hole is opened at the lower end of the mounting hole. A water pump is fixedly installed in one of the mounting holes. A water inlet pipe is fixedly installed in the other mounting hole. A drain pipe is fixedly installed at the output end of the water pump.

[0006] Specifically, the drill bucket assembly includes a first connecting rod, which is fixedly connected to the outer wall of the fixed cylinder. A drill bucket is fixedly installed on the first connecting rod. The lower end of the drill bucket has an inclined feed hole. Two rows of inclined cutting teeth are fixedly installed on the lower surface of the drill bucket, and the two rows of cutting teeth are located on one side of the two feed holes. The upper surface of the first connecting rod is arc-shaped. A stirring plate is fixedly installed at the bottom of the inside of the drill bucket.

[0007] Specifically, the sliding assembly includes two slide blocks, both of which are slidably connected to the main mast. One slide block is fixedly connected to the power head, and the other slide block is rotatably connected to the mechanical lock drill rod. A drive cylinder is fixedly installed on the main mast, and the output end of the drive cylinder is fixedly connected to one of the slide blocks.

[0008] Specifically, the goose head assembly includes a cable conveyor wheel, which is rotatably connected to the top of the main mast via a rotating shaft. A winch cable is conveyed on the cable conveyor wheel, and one end of the winch cable is fixedly connected to one of the slides.

[0009] Specifically, the elastic component includes a T-slot, which is formed at the lower end of the mechanical lock drill rod. A T-rod is slidably connected in the T-slot, and the lower end of the T-rod is fixedly connected to the fixed cylinder by a bolt assembly. A lower pressure plate is sleeved on the T-rod, and a spring is sleeved on the T-rod.

[0010] Specifically, the upper end of the spring abuts against the lower end of the mechanical lock drill rod, and the lower end of the spring abuts against the upper surface of the lower pressure plate.

[0011] Specifically, the bolt assembly includes mounting screw holes, which are formed on the fixed cylinder and the T-shaped rod, and the mounting screw holes on the fixed cylinder and the T-shaped rod are threaded together to connect to the mounting bolt.

[0012] Specifically, the second connecting rod is rectangular in shape, and the two side walls of the second connecting rod fit against the two side walls of the rectangular hole, and the lower surface of the mounting base is arc-shaped.

[0013] The beneficial effects of this invention are as follows: The drilling device for bored piles described in this invention, by installing a mixing plate inside the drill bucket and continuously injecting water through the water inlet pipe and pumping out mud and water in real time, transforms the traditional solid soil collection method into a fluidized continuous discharge mode. This ensures that the drill bucket always maintains an effective volume margin, enabling long-stroke continuous drilling operations without frequent drilling and soil unloading. This significantly reduces auxiliary operation time and greatly improves construction efficiency and economic benefits. At the same time, the negative pressure environment formed at the bottom of the hole during the drainage process effectively reduces the water head pressure inside the hole, helping to maintain hole wall stability and suppressing the risk of hole collapse and diameter reduction. This invention improves the quality of pile hole formation, making it particularly suitable for cast-in-place pile construction in water-rich strata and complex geological conditions. Furthermore, it establishes a dual anti-rotation protection mechanism for different working conditions above and below ground during drilling. This mechanism combines external ground-based equipment locking with underground cylinder-driven limit rollers pressing against the well wall. The rolling contact between the rollers and the well wall effectively suppresses the rotation of the grid cylinder while not hindering the lifting and lowering motion, ensuring that the inlet and outlet pipes remain statically arranged throughout the entire depth range. This fundamentally eliminates pipe entanglement accidents and fully guarantees the continuity and safety of drilling operations. Attached Figure Description

[0014] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0015] Figure 1 A schematic diagram of the external structure of a drilling device for a bored pile hole provided by the present invention; Figure 2 A schematic diagram of the connection structure between the T-shaped rod and the drill bucket of a drilling device for bored pile holes provided by the present invention; Figure 3 Exploded view of the T-shaped rod and drill bucket of a drilling device for a bored pile hole provided by the present invention; Figure 4 An exploded view of the elastic component of a drilling device for a bored pile hole provided by the present invention; Figure 5 A schematic diagram of the rotating cylinder and the blocking cylinder of a drilling device for a bored pile hole provided by the present invention; Figure 6 A schematic diagram of the structure of the mounting base of the drilling device for bored pile holes provided by the present invention; Figure 7 A top view of the drill bucket structure of a drilling device for a bored pile hole provided by the present invention; Figure 8This is a schematic diagram of the drill bucket structure of a drilling device for a bored pile hole provided by the present invention.

[0016] In the diagram: 1. Main mast; 2. Power head; 3. Mechanically locked drill rod; 4. Fixed cylinder; 5. First connecting rod; 6. Drill bucket; 7. Feed hole; 8. Cutting tooth; 9. Rotating cylinder; 10. Second connecting rod; 11. Barrier cylinder; 12. Limiting hole; 13. Cylinder; 14. U-shaped mounting bracket; 15. Limiting roller; 16. Mounting seat; 17. Rectangular hole; 18. Mounting hole; 19. Water pump; 20. Water inlet pipe; 21. Drain pipe; 22. Slide seat; 23. Drive cylinder; 24. Cable conveyor wheel; 25. Hoisting cable; 26. T-slot; 27. T-bar; 28. Lower pressure plate; 29. ​​Spring; 30. Mounting screw hole; 31. Mounting bolt; 32. Mixing plate; 33. Through hole. Detailed Implementation

[0017] like Figures 1-8 As shown, the present invention provides the following technical solution: Example 1: A drilling device for bored pile holes includes a main mast 1, which is mounted on a tracked chassis. A sliding assembly is provided on the main mast 1, and a power head 2 is fixedly installed on the sliding assembly. A mechanically locked drill rod 3 is sleeved inside the power head 2. The upper end of the mechanically locked drill rod 3 is rotatably connected to the sliding assembly. A gooseneck assembly for assisting the lifting and lowering of the sliding assembly is provided at the top of the main mast 1. The sliding assembly is used to limit the vertical lifting and lowering path of the power head 2 and the mechanically locked drill rod 3. An elastic assembly for buffering is provided at the lower end of the mechanically locked drill rod 3. A fixed cylinder 4 is sleeved on the lower end of the elastic assembly. The elastic assembly and the fixed cylinder 4 are fixedly connected by a bolt assembly. A drill bucket assembly is fixedly installed on the fixed cylinder 4. A rotating cylinder 9 is rotatably connected to the outer wall of the fixed cylinder 4. Two second connecting rods 10 are fixedly installed on the outer wall of the rotating cylinder 9. A baffle cylinder 11 is fixedly installed on both second connecting rods 10. Two limiting holes 12 are opened on the baffle cylinder 11. A cylinder 13 is fixedly installed on the rotating cylinder 9. A U-shaped mounting bracket 14 is fixedly installed at the output end of the cylinder 13. A limiting roller 15 is rotatably connected inside the U-shaped mounting bracket 14. A mounting seat 16 is sleeved on both second connecting rods 10. A rectangular hole 17 is opened through the mounting seat 16. The mounting seat 16 is slidably connected to the second connecting rod 10 through the rectangular hole 17. A mounting hole 18 is opened on the mounting seat 16. A through hole 33 is opened through the lower end of the mounting hole 18. A water pump 19 is fixedly installed in one of the mounting holes 18. A water inlet pipe 20 is fixedly installed in the other mounting hole 18. A drain pipe 21 is fixedly installed at the output end of the water pump 19.

[0018] The drill bucket assembly includes a first connecting rod 5, which is fixedly connected to the outer wall of the fixed cylinder 4. A drill bucket 6 is fixedly mounted on the first connecting rod 5. The lower end of the drill bucket 6 has an inclined feed hole 7. Two rows of inclined cutting teeth 8 are fixedly mounted on the lower surface of the drill bucket 6, and the two rows of cutting teeth 8 are located on one side of the two feed holes 7. The upper surface of the first connecting rod 5 is arc-shaped. A stirring plate 32 is fixedly mounted on the bottom of the inside of the drill bucket 6. The cutting teeth 8 cut into the soil or rock layer at an inclined angle when the drill bucket 6 rotates. This effectively reduces cutting resistance and improves rock-breaking efficiency; the inclined feed hole 7 facilitates the smooth entry of slag into the drill bucket 6 under the action of centrifugal force, reducing the risk of feed blockage; the mixing plate 32 fully mixes the slag and injected water when the drill bucket 6 rotates, accelerating the formation of mud-water fluidization and providing conditions for continuous slag discharge; the arc-shaped setting on the upper surface of the first connecting rod 5 can cooperate with the arc-shaped surface of the lower surface of the mounting base 16 when the drill bucket 6 rotates, and after the mounting base 16 sinks to the working position, it is lifted by the arc surface to avoid interfering with the normal rotation of the drill bucket 6, thereby ensuring the smooth operation of the drilling process.

[0019] The sliding assembly includes two sliding blocks 22, both of which are slidably connected to the main mast 1. One sliding block 22 is fixedly connected to the power head 2, and the other sliding block 22 is rotatably connected to the mechanically locked drill rod 3. A drive cylinder 23 is fixedly installed on the main mast 1, and the output end of the drive cylinder 23 is fixedly connected to one of the sliding blocks 22. The two sliding blocks 22 respectively undertake the lifting and guiding functions of the power head 2 and the mechanically locked drill rod 3, ensuring that they lift and lower in a straight line along the main mast 1, effectively preventing hole position deviation caused by skew during drilling. The upper ends of the power head 2 and the mechanically locked drill rod 3 are independently slidably connected, allowing the power head 2 to drive the drill rod to rotate independently, while the upper sliding block of the mechanically locked drill rod 3 only serves as a guide and suspension. The two do not interfere with each other, ensuring the reliability of power transmission and improving the stability of the lifting system. The drive cylinder 23 provides controllable feed pressure, allowing the drill bucket 6 to maintain a constant downward pressure during drilling, adapting to the drilling needs of different formations.

[0020] The goose-head assembly includes a cable conveyor wheel 24, which is rotatably connected to the top of the main mast 1 via a rotating shaft. A winch cable 25 is conveyed on the cable conveyor wheel 24. One end of the winch cable 25 is fixedly connected to one of the slides 22, and the other end of the winch cable 25 is connected to a winch on a tracked chassis. The winch drives the slides 22 to rise and fall along the main mast 1 after the winch cable 25 is reversed via the cable conveyor wheel 24, realizing the rapid lifting and lowering of the drill bucket 6. The rotatable connection of the cable conveyor wheel 24 can effectively reduce the wear of the winch cable 25 during the reversal process, extend the service life of the cable, and at the same time ensure the smoothness and response speed of the lifting action, significantly shorten the auxiliary operation time, and work in conjunction with the continuous slag removal system to further improve the overall construction efficiency.

[0021] The bolt assembly includes mounting screw holes 30, which are formed on the fixed cylinder 4 and the T-shaped rod 27. The mounting screw holes 30 on the fixed cylinder 4 and the T-shaped rod 27 are threaded together with mounting bolts 31. By using the threaded connection between the mounting bolts 31 and the mounting screw holes 30, a detachable fixed connection between the fixed cylinder 4 and the T-shaped rod 27 can be achieved. This ensures the connection rigidity between the drill bucket 6 and the mechanically locked drill rod 3 during operation, preventing loosening during drilling, and also facilitates the quick disassembly and replacement of the drill bucket 6, reducing the difficulty of maintenance and repair.

[0022] The second connecting rod 10 is rectangular, with its two side walls fitting against the two side walls of the rectangular hole 17. The lower surface of the mounting base 16 is arc-shaped, and the rectangular cross-section of the second connecting rod 10 fits against the wall of the rectangular hole 17 on the mounting base 16, forming a circumferential limiting structure. This effectively prevents the mounting base 16 from rotating around the axis on the second connecting rod 10, ensuring that the mounting base 16 always maintains the correct installation angle, thereby stabilizing the positions of the water inlet pipe 20 and the water pump 19. The arc shape of the lower surface of the mounting base 16 matches the arc shape of the upper surface of the first connecting rod 5. During the rotation of the drill bucket 6, the arc surface contacts the mounting base 16, allowing it to be smoothly lifted, avoiding interference with the rotating drill bucket 6 and ensuring coordinated movement of all components. Simultaneously, the mounting base 16 can automatically return to the working position when the drill bucket 6 is stationary or descending, without the need for additional driving components, simplifying the structure and improving operational reliability.

[0023] When using it, follow these steps: Step 1: The tracked chassis raises the main mast 1 using the luffing cylinder, and then moves the main mast 1 to directly above the drill bucket 6. At this point, the rotating cylinder 9 is fitted onto the fixed cylinder 4, and the winch unwinds the winch cable 25. The mechanical lock drill rod 3 then descends, allowing the T-shaped rod 27 to be inserted into the fixed cylinder 4. The T-shaped rod 27 and the fixed cylinder 4 are then fixed by connecting the mounting bolt 31 to the mounting screw hole 30, thus completing the connection between the drill bucket 6 and the mechanical lock drill rod 3.

[0024] Step 2: The tracked chassis moves the drill bucket 6 to the marked position of the grouting pile hole. Then, the power head 2 can be started to drive the mechanical lock drill rod 3 and the drill bucket 6 to rotate. The cutting teeth 8 will first penetrate the soil, gravel, and weathered rock to cut the soil and crush the rock, so that the slag can enter the drill bucket 6 through the feed hole 7.

[0025] Step 3: Simultaneously start the external water injection equipment to inject clean water into the water inlet pipe 20. The water inlet pipe 20 pours water into the drill bucket 6 at an angle through the inclined through hole 33, thereby dispersing the incoming soil. When the drill bucket 6 rotates, it will also drive the soil and water to rotate through the stirring plate 32, thereby mixing into mud-water. The mounting base 16 will descend under its own weight, causing the lower end of the through hole 33 to descend into the drill bucket 6. Then, the water pump 19 can be started to pump out the mud-water in the drill bucket 6, thereby ensuring that the soil in the drill bucket 6 will not be filled and can continue to operate.

[0026] Step 4: When the drill bucket 6 is still on the ground, a support can be set up on the ground, and the fixing device on the support can be inserted into the limiting hole 12 on the grid plate 11 to fix the grid cylinder 11 so that the grid cylinder 11 cannot rotate, thus avoiding the water inlet pipe 20 and the drain pipe 21 from getting tangled on the mechanical lock drill rod 3. When the drill bucket 6 descends to the ground, the cylinder 13 is activated, which drives the U-shaped mounting frame 14 to move outward. The U-shaped mounting frame 14 then moves the limiting roller 15 to the outside of the blocking cylinder 11 and abuts against the inner wall of the pile hole. The limiting hole 12 supports the U-shaped mounting frame 14 and the limiting roller 15. Thus, the lateral blocking between the limiting roller 15 and the inner wall of the pile hole prevents the blocking cylinder 11 from rotating. The rolling of the limiting roller 15 does not affect the raising and lowering of the blocking cylinder 11 or the drill bucket 6. Furthermore, during the rotation of the drill bucket 6, the arc surface of the lower surface of the mounting base 16 will abut against the arc surface of the upper surface of the first connecting rod 5, thereby pushing the mounting base 16 to rise, thus preventing the mounting base 16 from blocking and affecting the rotation of the drill bucket 6.

[0027] Example 2: The technical solutions in this example that differ from Example 1 include: The elastic component includes a T-slot 26, which is located at the lower end of the mechanical lock drill rod 3. A T-rod 27 is slidably connected within the T-slot 26. The lower end of the T-rod 27 is fixedly connected to the fixed cylinder 4 via a bolt assembly. A lower pressure plate 28 is fitted onto the T-rod 27, and a spring 29 is fitted onto the T-rod 27. The upper end of the spring 29 abuts against the lower end of the mechanical lock drill rod 3, and the lower end of the spring 29 abuts against the upper surface of the lower pressure plate 28. When the drill bucket 6 experiences external resistance and rebounds, it pushes the T-rod 27 upward. The T-rod 27 rises within the T-slot 26 and compresses the spring 29, thereby buffering the rebound energy. Simultaneously, the mechanical lock drill rod 3 continuously drives the drill bucket 6 to operate through the cooperation of the T-slot 26 and the T-rod 27.

Claims

1. A drilling device for bored pile holes, comprising a main mast (1), characterized in that, A sliding assembly is provided on the main mast (1), and a power head (2) is fixedly installed on the sliding assembly. A mechanical lock drill rod (3) is sleeved inside the power head (2). The upper end of the mechanical lock drill rod (3) is rotatably connected to the sliding assembly. A goose head assembly for assisting the sliding assembly in raising and lowering is provided at the top of the main mast (1). The sliding assembly is used to limit the vertical raising and lowering path of the power head (2) and the mechanical lock drill rod (3). An elastic assembly for buffering is provided at the lower end of the mechanical lock drill rod (3). A fixed cylinder (4) is sleeved on the lower end of the elastic assembly. The elastic assembly and the fixed cylinder (4) are fixedly connected by a bolt assembly. A drill bucket assembly is fixedly installed on the fixed cylinder (4). A rotating cylinder (9) is rotatably connected to the outer wall of the fixed cylinder (4). Two second connecting rods (10) are fixedly installed on the outer wall of the rotating cylinder (9). A baffle cylinder (11) is fixedly installed on both second connecting rods (10). Two limiting holes (12) are opened on the baffle cylinder (11). A cylinder (13) is fixedly installed on the rotating cylinder (9). A U-shaped mounting bracket (14) is fixedly installed at the output end of the cylinder (13). A limiting roller (15) is rotatably connected inside the U-shaped mounting bracket (14). The two second connecting rods (10) Each of the components is fitted with a mounting base (16), and a rectangular hole (17) is provided through the mounting base (16). The mounting base (16) is slidably connected to the second connecting rod (10) through the rectangular hole (17). The mounting base (16) is provided with a mounting hole (18), and a through hole (33) is provided through the lower end of the mounting hole (18). A water pump (19) is fixedly installed in one of the mounting holes (18), and a water inlet pipe (20) is fixedly installed in the other mounting hole (18). A drain pipe (21) is fixedly installed at the output end of the water pump (19).

2. The drilling device for a bored pile hole according to claim 1, characterized in that: The drill assembly includes a first connecting rod (5), which is fixedly connected to the outer wall of the fixed cylinder (4). A drill bucket (6) is fixedly installed on the first connecting rod (5). The lower end of the drill bucket (6) is provided with an inclined feed hole (7). Two rows of inclined cutting teeth (8) are fixedly installed on the lower surface of the drill bucket (6), and the two rows of cutting teeth (8) are located on one side of the two feed holes (7). The upper surface of the first connecting rod (5) is arc-shaped. A stirring plate (32) is fixedly installed at the bottom of the inside of the drill bucket (6).

3. The drilling device for a bored pile hole according to claim 1, characterized in that: The sliding assembly includes two slides (22), both of which are slidably connected to the main mast (1). One of the slides (22) is fixedly connected to the power head (2), and the other slide (22) is rotatably connected to the mechanical lock drill rod (3). A drive cylinder (23) is fixedly installed on the main mast (1), and the output end of the drive cylinder (23) is fixedly connected to one of the slides (22).

4. The drilling device for a bored pile hole according to claim 1, characterized in that: The goose head assembly includes a cable conveyor wheel (24), which is rotatably connected to the top of the main mast (1) via a rotating shaft. A winch cable (25) is conveyed on the cable conveyor wheel (24), and one end of the winch cable (25) is fixedly connected to one of the slides (22).

5. The drilling device for a bored pile hole according to claim 1, characterized in that: The elastic component includes a T-slot (26), which is located at the lower end of the mechanical lock drill rod (3). A T-rod (27) is slidably connected in the T-slot (26). The lower end of the T-rod (27) is fixedly connected to the fixed cylinder (4) by a bolt assembly. A lower pressure plate (28) is sleeved on the T-rod (27), and a spring (29) is sleeved on the T-rod (27).

6. The drilling device for a bored pile hole according to claim 5, characterized in that: The upper end of the spring (29) abuts against the lower end of the mechanical lock drill rod (3), and the lower end of the spring (29) abuts against the upper surface of the lower pressure plate (28).

7. The drilling device for a bored pile hole according to claim 1, characterized in that: The bolt assembly includes mounting screw holes (30) which are formed on the fixed cylinder (4) and the T-shaped rod (27). The mounting screw holes (30) on the fixed cylinder (4) and the T-shaped rod (27) are threaded together with mounting bolts (31).

8. The drilling device for a bored pile hole according to claim 1, characterized in that: The second connecting rod (10) is rectangular, and the two sides of the connecting rod (10) are in contact with the two sides of the rectangular hole (17), and the lower surface of the mounting base (16) is arc-shaped.

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