Single-shaft anti-slurry-leakage cement mixing pile drill bit structure

Abstract

The invention relates to a single-shaft anti-slurry-leakage cement mixing pile drill bit structure which comprises a drill bit body, the drill bit body is sequentially provided with an upper horizontal cutter strip, a lower horizontal cutter strip and a spiral cutter strip from top to bottom, the upper horizontal cutter strip is connected with the upper ends of a plurality of upper vertical cutter strips, and the lower horizontal cutter strip is connected with the lower ends of a plurality of lower vertical cutter strips. The lower vertical cutter strips are distributed in the extending direction of the lower horizontal cutter strips, lower vertical cutter strip cutting edges extending in the extending direction of the lower vertical cutter strips are arranged at the two ends, in the circumferential direction of the drill bit body, of the lower vertical cutter strips, and the lower ends of the upper vertical cutter strips downwards exceed the upper ends of the lower vertical cutter strips. The drill bit has the advantages that cement and soil can be fully mixed to reduce loss when passing through a sand layer, and the problem that cement is prone to loss when passing through the sand layer due to the fact that an existing drill bit cannot be fully mixed and smashed during construction is solved.

Description

Technical Field

[0001] The invention relates to the technical field of pile foundation construction, in particular to a single-axis anti-leakage cement mixing pile drill bit structure. Background Art

[0002] Deep cement mixing pile is a commonly used foundation reinforcement method. It has the advantages of simple construction, short construction period and low cost, and has been widely used in domestic and foreign projects. The principle is to use the pile driver drill to mix the soil, and the cement slurry is sprayed out from the pile driver drill hole to fully mix with the soil to produce a chemical reaction and harden.

[0003] The common cement mixing pile driver drill bit structure includes a drill bit body, a cement slurry channel is arranged inside the drill bit body along the length axis, the drill bit blade is in the form of a multi-layer blade, a slurry inlet is arranged at the upper part of the drill bit body, and a grouting port is arranged at the lower part of the drill bit body, and the slurry inlet and the grouting port are connected through the cement slurry channel inside the drill bit.

[0004] When constructing soil in complex strata, cement mixing piles using traditional drill bits usually have the following problems: when there are sand layers mixed in the clay layer, the cement slurry sprayed out by the traditional drill bit seeps through the sand layer without being fully mixed with the soil, resulting in slurry waste and reduced pile quality; traditional drill bits are very likely to stick to the soil during the mixing pile construction process, resulting in drill sticking problems; traditional drill bits cannot easily break up soil blocks, resulting in larger soil blocks that cannot be mixed with cement slurry; when cement mixing piles are constructed at the bottom of the pile, the sprayed cement slurry is insufficient to penetrate the soil, resulting in cement slurry gathering near the drill bit; when constructing deep cement mixing piles, traditional drill bits cannot drill easily, resulting in "drill stuck". Summary of the invention

[0005] The present invention provides a single-axis anti-leakage cement mixing pile drill bit structure which can fully mix cement with soil and reduce loss when passing through a sand layer, thereby solving the problem that cement can not be fully mixed and crushed during construction, resulting in easy loss of cement when passing through a sand layer.

[0006] The above technical problems are solved by the following technical solutions: a single-axis anti-leakage cement mixing pile drill bit structure, including a drill bit body, a cement slurry input channel is provided in the drill bit body, and the cement slurry input channel is provided with a grouting port, characterized in that the drill bit body is provided with an upper horizontal blade, a lower horizontal blade and a spiral blade in sequence from top to bottom, and the upper horizontal blade portions are provided with cutting edges extending along the extension direction of the upper horizontal blade at both ends of the drill bit body along the circumference, and the upper horizontal blade is connected to the upper ends of a plurality of upper vertical blades, and the upper vertical blades are divided along the extension direction of the upper horizontal blade. The upper vertical blade is provided with an upper vertical blade portion cutting edge extending in the extension direction of the upper vertical blade at both ends of the drill bit body along the circumference, and the lower horizontal blade is provided with a lower horizontal blade portion cutting edge extending in the extension direction of the lower horizontal blade at both ends of the drill bit body along the circumference, and the lower horizontal blade is connected with the lower ends of a plurality of lower vertical blades, and the lower vertical blades are distributed along the extension direction of the lower horizontal blade, and the lower vertical blade is provided with a lower vertical blade portion cutting edge extending in the extension direction of the lower vertical blade at both ends of the drill bit body along the circumference, and the lower end of the upper vertical blade extends downward beyond the upper end of the lower vertical blade. This technical solution, by providing vertical blades, overcomes the problem of insufficient blade mixing and loss when the traditional drill bit passes through a local sand layer during construction, and at the same time, the vertical blade can better cut the soil, improve the mixing degree of cement slurry and soil, and improve the uniformity and strength of pile formation. The drill bit of the present invention is provided with three types of blade forms, two different nozzles and two types of drill bit lower end tips, which can more effectively solve the problems of slurry leakage, drill sticking, difficulty in drilling and so on in the construction of cement mixing piles in complex strata, and improve the construction quality and efficiency.

[0007] Preferably, the lower end surface of the drill body is also provided with a plurality of drill bits distributed along the circumference of the drill body, and the lower ends of all the drill bits are gathered together, so as to simultaneously cut the soil and assist the drill bit in drilling, thereby improving the construction efficiency when constructing in deep layers or hard soil.

[0008] Preferably, the grouting port is located between the upper horizontal blade and the lower horizontal blade, which can effectively prevent the cement slurry from being injected into the hole wall and then lost when passing through the sandstone layer.

[0009] Preferably, an airflow input channel is provided in the drill bit body, and the airflow input channel is provided with an air jet port penetrating the circumference of the drill bit body. In order to change the deficiency of only spraying grout during construction of traditional drill bits, a cement slurry pipe and a high-pressure air pipe are provided inside the drill bit, so that cement slurry and compressed air can be sprayed out simultaneously during construction. The spraying of compressed air can form a certain space between the drill bit and the soil during the mixing process, which is convenient for the cement slurry to be sprayed out. At the same time, the compressed air can also separate the soil blocks attached to the blades, prevent the problem of the drill sticking during mixing, and enable the soil to achieve the best mixing effect.

[0010] Preferably, the air jet and the grouting port are located on the same horizontal plane, which can improve the depth and efficiency of cement slurry mixing into the soil.

[0011] Preferably, when the drill bit body rotates toward drilling into the soil, the air jets and the grouting ports are distributed from front to back along the rotation direction of the drill bit body, so that airflow can form gaps in the soil slurry before the cement slurry is sprayed out, thereby facilitating the mixing of cement slurry.

[0012] Preferably, the upper horizontal blade and the lower horizontal blade are arranged at intervals along the circumference of the drill bit body, which can improve the cutting effect on the soil and facilitate slurry formation.

[0013] Preferably, it also includes an isolation tube sleeved on the drill body, the grouting port is located inside the space surrounded by the isolation tube, the isolation tube is connected to the suspension ring through a connecting rod, the suspension ring is sleeved on the drill body, a supporting ring and a pressing ring located above the supporting ring are provided on the drill body, the suspension ring is located between the supporting ring and the pressing ring, the supporting ring is used to push up the suspension ring when the drill body moves upward, and the pressing ring is used to press down the suspension ring when the drill body moves downward. The formed mixing pile hole can be isolated from the surrounding land, thereby preferably avoiding the loss of cement slurry through the sand and gravel layer, the isolation sleeve can be raised and lowered together with the drill body without synchronous rotation, thereby ensuring the isolation of dynamic grouting from the hole wall and avoiding the increase in equipment power required to form the mixing pile due to the increase in load.

[0014] Preferably, the lower horizontal blade is fixedly connected to the drill body, the drill body is sleeved with an inner gear ring and an outer gear ring, the outer gear ring is coaxially fixed to the drill body, the inner gear ring is meshed with a plurality of intermediate gears, the intermediate gears are meshed with the inner gear ring, the intermediate gears are distributed along the circumference of the inner gear ring, the outer gear ring can be rotatably supported on a boss fixed to the drill body, the upper horizontal blade is fixed to the outer gear ring, and the upper vertical blade and the lower vertical blade are staggered along the circumference of the drill body. A connected drill body is realized to make the upper and lower vertical blades rotate in opposite directions, which can make the relative speed of the vertical blades fast when the drill body rotates, thereby improving the crushing and cutting effect on the soil.

[0015] Preferably, the outer end of the shotcrete port is provided with a straight section, the opening direction of the straight section is inclined upward, a plug opening outward is passed through the shotcrete port, the plug is connected to the drill bit body by a limit cable preventing the plug from escaping from the shotcrete port, a connecting through hole extending up and down is provided at the outer end of the plug, the opening width of the connecting through hole gradually increases from top to bottom, the wall surface of the hole wall of the connecting through hole on one side of the shotcrete port is a vertical plane, the outer end face of the plug is parallel to the wall surface of the hole wall of the connecting through hole away from the cement output side, a lifting rod is passed through the connecting through hole, a pressing rod is provided on the lifting rod, and a side of the lifting rod away from the shotcrete port is provided with a pressing rod for squeezing the connecting through hole The hole wall makes the plug lose the sealing effect of the extrusion slope on the spraying port, the pressure rod is parallel to the extrusion slope, and a guide groove is formed between the pressure rod and the extrusion slope. The side wall of the plug away from the cement output hole is inserted into the guide groove, and the upper end of the lifting rod is connected with the guide plate after passing through the guide sleeve, and the guide sleeve is fixed with the drill body. When the drill body rotates in the direction of drilling into the soil, the fluid in the borehole passes through the guide plate, which generates a force to float the guide plate, causing the lifting rod to rise and drive the plug to open. When the drill body rotates in the direction of pulling out the soil, the fluid in the borehole passes through the guide plate, which generates a force to press the guide plate downward, causing the lifting rod to descend and drive the plug to close. It can make cement slurry output when drilling in, and not output when rising. The spraying port is not easy to be blocked.

[0016] The present invention has the following advantages: the present invention overcomes the problem of insufficient blade mixing and loss when the traditional drill bit passes through the local sand layer during the construction process by setting a vertical blade. At the same time, the vertical blade can better cut the soil, improve the mixing degree of cement slurry and soil, and improve the uniformity and strength of the pile. The setting of the spiral annular blade and the bottom double-tooth spiral tip can simultaneously cut the soil and assist the drill bit in drilling, thereby improving the construction efficiency when constructing in deep layers or harder soils. To change the deficiency of only spraying grout during construction of the traditional drill bit, a cement slurry pipe and a high-pressure air pipe are set inside the drill bit, so that cement slurry and compressed air can be sprayed out at the same time during construction. The spraying of compressed air can form a certain space between the drill bit and the soil during the mixing process, which is convenient for the spraying of cement slurry. At the same time, the compressed air can also separate the soil blocks attached to the blades, prevent the problem of holding the drill during mixing, and enable the soil to achieve the best mixing effect. The drill bit of the present invention is provided with three types of blade forms, two different nozzles and two types of drill bit lower end tips, which can more effectively solve the problems of slurry leakage, drill sticking, difficulty in drilling and so on in the construction of cement mixing piles in complex strata, and improve the construction quality and efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a front view schematic diagram of the first embodiment; Figure 2 is a side view schematic diagram of embodiment 1; Figure 3is a schematic cross-sectional view of a drill bit body of Embodiment 2; Figure 4 is an axial cross-sectional schematic diagram of embodiment 2; Figure 5 for Figure 4 A local enlarged schematic diagram of point A.

[0018] In the figure: drill body 1, cement slurry input channel 2, shotcrete port 3, air flow input channel 4, air jet port 5, upper horizontal blade 6, lower horizontal blade 7, spiral blade 8, upper vertical blade 9, lower vertical blade 10, drill bit 11, isolation tube 12, connecting rod 13, suspension ring 14, supporting ring 15, pressing ring 16, inner gear ring 17, outer gear ring 18, intermediate gear 19, boss 20, supporting ball 21, straight line segment 22, plug 23, limit cable 24, connecting through hole 25, wall surface 26 of the hole wall of the connecting through hole on the side of the shotcrete port, lifting rod 27, pressing rod 28, extrusion slope 29, side wall 30 of the plug away from the cement output hole side, guide sleeve 31, guide plate 32. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] Example 1, see Figure 1 and Figure 2 A single-axis anti-leakage cement mixing pile drill bit structure includes a drill bit body 1, a cement slurry input channel 2 is provided in the drill bit body, and a grouting port 3 is provided in the cement slurry input channel. An airflow input channel 4 is provided in the drill bit body, and an airflow input channel is provided with an air jet 5 that passes through the circumference of the drill bit body. The air jet and the grouting port are located on the same horizontal plane. When the drill bit body rotates in the direction of drilling into the soil, the air jet and the grouting port are distributed from front to back along the rotation direction of the drill bit body. When in use, the inlet end of the cement slurry input channel is connected to the slurry making equipment, and the inlet end of the airflow input channel is connected to the air compressor.

[0021] The drill bit body is provided with an upper horizontal blade 6, a lower horizontal blade 7 and a spiral blade 8 in sequence from top to bottom. The upper horizontal blade portions are provided with cutting edges extending in the extension direction of the upper horizontal blade at both ends of the upper horizontal blade along the circumference of the drill bit body. The upper horizontal blade is connected with the upper ends of a plurality of upper vertical blades 9. The upper horizontal blade exceeds the spiral blade in the radial direction of the drill bit body. The upper vertical blades are distributed along the extension direction of the upper horizontal blades. The upper vertical blade portions are provided with cutting edges extending in the extension direction of the upper vertical blade at both ends of the upper vertical blade along the circumference of the drill bit body. The lower horizontal blade portion cutting edges extending along the extension direction of the lower horizontal blade are provided at both ends of the drill bit body along the circumference direction of the drill bit body. The lower horizontal blade is connected to the lower ends of a plurality of lower vertical blades 10. The lower vertical blades are distributed along the extension direction of the lower horizontal blade. The lower vertical blade portions cutting edges extending along the extension direction of the lower vertical blade are provided at both ends of the drill bit body along the circumference direction of the drill bit body. The lower end of the upper vertical blade extends downward beyond the upper end of the lower vertical blade. A plurality of drill bits 11 distributed along the circumference direction of the drill bit body are also provided on the lower end surface of the drill bit body. The lower ends of all the drill bits converge together. The grouting port is located between the upper horizontal blade and the lower horizontal blade. The upper horizontal blade and the lower horizontal blade are spaced apart along the circumference direction of the drill bit body.

[0022] Embodiment 2 is different from Embodiment 1 in that: See also Figures 3 to 5 , and further includes an isolation tube 12 sleeved on the drill body, and the grouting port is located inside the space surrounded by the isolation tube. The isolation tube is connected with a suspension ring 14 through a connecting rod 13. The suspension ring is sleeved on the drill body, and a supporting ring 15 and a pressing ring 16 located above the supporting ring are provided on the drill body. The suspension ring is located between the supporting ring and the pressing ring. The supporting ring is used to push up the suspension ring when the drill body moves upward, and the pressing ring is used to press down the suspension ring when the drill body moves downward.

[0023] The lower horizontal blade is fixedly connected to the drill body. The drill body is sleeved with an inner gear ring 17 and an outer gear ring 18. The outer gear ring is coaxially fixed to the drill body. The inner gear ring is meshed with a plurality of intermediate gears 19. The intermediate gears are meshed with the inner gear ring. The intermediate gears are distributed along the circumference of the inner gear ring. The outer gear ring can be rotatably supported on a boss 20 fixed to the drill body. Specifically, a boss annular groove extending along the circumference of the drill body is provided on the upper surface of the convex strip, and a gear ring annular groove extending along the circumference of the drill body is provided on the lower surface of the outer gear ring. The boss annular groove is aligned with the gear ring annular groove, and a plurality of support balls 21 supported in the Chongqing annular groove are provided in the boss annular groove. The upper horizontal blade is fixed on the outer gear ring, and the upper vertical blade and the lower vertical blade are staggered along the circumference of the drill body.

[0024] A straight section 22 is provided at the outer end of the grouting port, and the opening direction of the straight section is inclined upward. A plug 23 opened outward is passed through the grouting port, and the plug is connected to the drill bit body through a limit cable 24 that prevents the plug from escaping from the grouting port. A connecting through hole 25 extending up and down is provided at the outer end of the plug, and the opening width of the connecting through hole gradually increases from top to bottom. The wall surface 26 of the hole wall of the connecting through hole on one side of the grouting port is a vertical plane, and the outer end surface of the plug is parallel to the wall surface of the hole wall of the connecting through hole away from the cement output side. A lifting rod 27 is passed through the connecting through hole, and a pressing rod 28 is provided on the lifting rod. The side of the lifting rod away from the grouting port is provided with a hole wall that squeezes the connecting through hole so that The plug loses its sealing effect on the extrusion slope 29 of the grouting port, the pressure rod is parallel to the extrusion slope, and a guide groove is formed between the pressure rod and the extrusion slope. The side wall 30 of the plug away from the cement output hole is inserted into the guide groove, and the upper end of the lifting rod passes through the guide sleeve 31 and is connected with the guide plate 32. The guide sleeve is fixed together with the drill bit body. When the drill bit body rotates in the direction of drilling into the soil, the fluid in the borehole passes through the guide plate, which generates a force to float the guide plate, causing the lifting rod to rise and drive the plug to open. When the drill bit body rotates in the direction of pulling out of the soil, the fluid in the borehole passes through the guide plate, which generates a force to press the guide plate downward, causing the lifting rod to descend and drive the plug to close.

[0025] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0026] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A single-axis anti-leakage cement mixing pile drill bit structure, comprising a drill bit body, a cement slurry input channel is provided in the drill bit body, and a grouting port is provided in the cement slurry input channel, characterized in that: The drill bit body is provided with an upper horizontal blade, a lower horizontal blade and a spiral blade in sequence from top to bottom, and the two ends of the upper horizontal blade along the circumference of the drill bit body are provided with upper horizontal blade portion cutting edges extending along the extension direction of the upper horizontal blade, and the upper horizontal blade is connected with the upper ends of a plurality of upper vertical blades, and the upper vertical blades are distributed along the extension direction of the upper horizontal blade, and the two ends of the upper vertical blade along the circumference of the drill bit body are provided with upper vertical blade portion cutting edges extending along the extension direction of the upper vertical blade, and the two ends of the lower horizontal blade along the circumference of the drill bit body are connected with the lower ends of the lower vertical blades, and the lower vertical blades are distributed along the extension direction of the lower horizontal blade, and the two ends of the lower vertical blade along the circumference of the drill bit body are provided with lower vertical blade portion cutting edges extending along the extension direction of the lower vertical blade, and the lower end of the upper vertical blade extends downward beyond the upper end of the lower vertical blade.

2. A single-axis anti-leakage cement mixing pile drill bit structure according to claim 1, characterized in that: A plurality of drill bits distributed along the circumference of the drill bit body are also arranged on the lower end surface of the drill bit body, and the lower ends of all the drill bits are gathered together.

3. The single-axis anti-leakage cement mixing pile drill bit structure according to claim 1, characterized in that: The spraying port is located between the upper horizontal blade and the lower horizontal blade.

4. The single-axis anti-leakage cement mixing pile drill bit structure according to claim 1, characterized in that: An airflow input channel is arranged in the drill bit body, and the airflow input channel is provided with an air jet port penetrating the peripheral surface of the drill bit body. To change the deficiency of only spraying grout during traditional drill construction, cement slurry pipes and high-pressure air pipes are set inside the drill bit, so that cement slurry and compressed air can be sprayed out simultaneously during construction. The spraying of compressed air can form a certain space between the drill bit and the soil during the mixing process, which is convenient for spraying cement slurry.

5. A single-axis anti-leakage cement mixing pile drill bit structure according to claim 4, characterized in that: The air jet and the shotcrete jet are located on the same horizontal plane.

6. A single-axis anti-leakage cement mixing pile drill bit structure according to claim 5, characterized in that: When the drill bit body rotates in the direction of drilling into the soil, the air jets and the grouting ports are distributed from front to back along the rotation direction of the drill bit body.

7. The single-axis anti-leakage cement mixing pile drill bit structure according to claim 1, characterized in that: The upper horizontal blade and the lower horizontal blade are arranged at intervals along the circumference of the drill body.

8. The single-axis anti-leakage cement mixing pile drill bit structure according to claim 1, characterized in that: It also includes an isolation tube sleeved on the drill bit body, the grouting port is located inside the space surrounded by the isolation tube, the isolation tube is connected to the suspension ring through a connecting rod, the suspension ring is sleeved on the drill bit body, the drill bit body is provided with a supporting ring and a pressing ring located above the supporting ring, the suspension ring is located between the supporting ring and the pressing ring, the supporting ring is used to push up the suspension ring when the drill bit body moves upward, and the pressing ring is used to press down the suspension ring when the drill bit body moves downward.

9. The single-axis anti-leakage cement mixing pile drill bit structure according to claim 1, characterized in that: The lower horizontal blade is fixedly connected to the drill bit body, and the drill bit body is sleeved with an inner gear ring and an outer gear ring. The outer gear ring is coaxially fixed to the drill bit body, the inner gear ring is meshed with a plurality of intermediate gears, and the intermediate gears are meshed with the inner gear ring. The intermediate gears are distributed along the circumference of the inner gear ring, and the outer gear ring can be rotatably supported on a boss fixed on the drill bit body. The upper horizontal blade is fixed on the outer gear ring, and the upper vertical blade and the lower vertical blade are staggered along the circumference of the drill bit body.

10. The single-axis anti-leakage cement mixing pile drill bit structure according to claim 1, characterized in that: The outer end of the grouting port is provided with a straight section, the opening direction of the straight section is inclined upward, a plug opening outward is passed through the grouting port, the plug is connected to the drill bit body by a limit cable preventing the plug from escaping from the grouting port, the outer end of the plug is provided with a connecting through hole extending up and down, the opening width of the connecting through hole gradually increases from top to bottom, the wall surface of the hole wall of the connecting through hole on one side of the grouting port is a vertical plane, the outer end surface of the plug is parallel to the wall surface of the hole wall of the connecting through hole away from the cement output side, a lifting rod is passed through the connecting through hole, a pressing rod is provided on the lifting rod, and a hole wall of the connecting through hole is squeezed on the side of the lifting rod away from the grouting port The extrusion slope makes the plug lose its sealing effect on the grouting port, the pressure rod is parallel to the extrusion slope, a guide groove is formed between the pressure rod and the extrusion slope, the side wall of the plug away from the cement output hole is inserted into the guide groove, the upper end of the lifting rod passes through the guide sleeve and is connected with the guide plate, the guide sleeve is fixed together with the drill body, when the drill body rotates in the direction of drilling into the soil, the fluid in the borehole passes through the guide plate, the force of floating the guide plate is generated, so that the lifting rod rises and drives the plug to open, when the drill body rotates in the direction of pulling out of the soil, the fluid in the borehole passes through the guide plate, the force of pressing the guide plate is generated, so that the lifting rod descends and drives the plug to close.

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