Large-diameter hard sand layer stirring screw drill bit

Abstract

The utility model relates to a large-diameter hard sand layer stirring screw drill bit which comprises a drill bit body and a drill body, the drill bit body is fixedly connected under the drill body, spiral blades used for guiding the drilling direction are arranged on the peripheral wall of the drill bit body, and long-wing stirring blades and short-wing stirring blades are arranged on the peripheral wall of the drill body. The spiral blade, the short-wing stirring blade and the long-wing stirring blade are sequentially arranged from the bottom to the top of the stirring screw drill bit; the short-wing stirring blade is located between the long-wing stirring blade and the spiral blade, the outer diameter of the short-wing stirring blade is smaller than that of the long-wing stirring blade, the outer diameter of the short-wing stirring blade is larger than that of the spiral blade, and the outer diameter of the long-wing stirring blade is equal to the pore-forming diameter; the drill bit is provided with a first channel capable of spraying high-pressure water flow, and a high-pressure nozzle is installed on the first channel and located in the center of the bottom of the drill bit. According to the utility model, the defects of the existing equipment drill bit are overcome, and the efficient stirring and pile planting construction can still be realized under the complicated geological condition.

Description

Technical Field

[0001] The utility model belongs to the technical field of pile driving construction, and particularly relates to a large-diameter stirring screw drill bit for hard sand layers. Background Technique

[0002] For mixing and driving piles, first, a deep mixing machine is used to cut and mix the soil mass and then inject cement slurry. High-speed cutting and mixing are carried out according to the preset grouting volume and cutting and mixing times to form a fluid cement-soil pile. Secondly, a precast pile is implanted into the cement-soil pile to form a composite pile foundation. Compared with the traditional bored cast-in-place pile process, mixing and driving piles have low cost, do not take soil, have no mud discharge, and high construction efficiency. Compared with the traditional precast concrete pile process, mixing and driving piles do not produce soil squeezing effect and can penetrate hard interlayers. It is a new type of pile foundation construction process with no pollution, low cost, high work efficiency, and good engineering quality, and is a pile foundation scheme widely promoted in recent years.

[0003] However, when facing the requirements of large-diameter hole forming and hard sand layers, the existing drill bits often face the problems of low efficiency and insufficient durability. The cutting force and hole-forming effect of traditional drill bits in hard sand layers are not good, resulting in slow penetration speed and serious wear, increasing the construction cost and time. The high hardness and complexity of hard sand layers put forward higher requirements for the structure of drill bits. Therefore, a drill bit with both high efficiency and high durability is needed. Summary of the Utility Model

[0004] The purpose of the utility model is to overcome the deficiencies existing in the prior art, and provide a large-diameter stirring screw drill bit for hard sand layers to overcome the deficiencies in the drill bits of existing equipment and ensure efficient mixing and driving pile construction under complex geological conditions.

[0005] The purpose of the utility model is completed by the following technical solutions. This large-diameter stirring screw drill bit for hard sand layers includes a drill bit and a drill body. The drill bit is fixedly connected directly below the drill body. A spiral blade for guiding the drilling direction is arranged on the outer peripheral wall of the drill bit. Long-wing stirring blades and short-wing stirring blades are arranged on the outer peripheral wall of the drill body. The spiral blade, the short-wing stirring blade, and the long-wing stirring blade are arranged in sequence from the bottom to the top of the stirring screw drill bit. The short-wing stirring blade is located between the long-wing stirring blade and the spiral blade. The outer diameter of the short-wing stirring blade is smaller than the outer diameter of the long-wing stirring blade, and the outer diameter of the short-wing stirring blade is larger than the outer diameter of the spiral blade. The outer diameter of the long-wing stirring blade is equal to the hole-forming diameter. A first channel capable of spraying high-pressure water flow is arranged on the drill bit, and a high-pressure nozzle is installed on the first channel. The high-pressure nozzle is located at the center of the bottom of the drill bit.

[0006] The beneficial effects of the present utility model are as follows: Compared with the prior art, a spiral blade, a short-wing blade, and a long-wing blade are sequentially arranged on the drill bit and the drill body, and the outer diameters increase step by step, realizing three-stage drilling and forming holes step by step, reducing the hole-forming resistance, prolonging the service life of the drill bit. At the same time, the combination design of the long and short blades optimizes the distribution of the cutting force, reduces the wear of a single blade. The design of the high-pressure nozzle and the drill bit with a guiding spiral blade reduces the drilling resistance, improves the hole-forming efficiency, effectively solves the problem of difficult footage in the process of large-diameter drilling, and improves the drilling efficiency in large-diameter hard sand layers.

[0007] Preferably, the drill bit is conical, the top of the drill bit is fixed to the axial end face of the drill body by welding, the high-pressure nozzle is fixedly installed at the center of the bottom of the drill bit, and the first channel is arranged along the axial center of the drill bit; By means of the conical drill bit and the high-pressure nozzle arranged at the bottom, high-pressure water flow can be sprayed. On the one hand, the high-pressure water flow softens the soil body, and on the other hand, it uses the water jet to cut the soil body, destroys the soil body structure, further reduces the footage resistance, and speeds up the footage speed.

[0008] Preferably, a circular tube is installed at the inner center of the drill body, and the circular tube is communicated with the first channel; This makes the water flow of the high-pressure nozzle smoother.

[0009] Preferably, an external joint for fixedly connecting the stirring screw drill bit and the drill pipe is installed and fixed on the axial other end face of the drill body, and a second channel is arranged at the inner center of the external joint, and the second channel is communicated with the circular tube; Through the setting of the above structure, it is not only convenient to fixedly connect the stirring screw drill bit and the drill pipe, but also enables the high-pressure water required by the high-pressure nozzle to flow in from the outside high pressure.

[0010] Preferably, positioning teeth are provided at the bottom of the spiral blade, the positioning teeth are located at the center of the bottom of the drill bit and protrude from the bottom of the drill bit, and the high-pressure nozzle is located inside the positioning teeth; Through the setting of the positioning teeth, the stirring screw drill bit can realize the positioning function in the initial stirring process. The above setting method of the high-pressure nozzle can prevent the stirring screw drill bit from being blocked during the cutting and stirring process with the soil body.

[0011] Preferably, a pair of long-wing stirring blades are provided and symmetrically distributed along the center of the drill body, and a pair of short-wing stirring blades are provided and symmetrically distributed along the center of the drill body; Through the setting of the above structure, the stability and linearity of the blades in the drilling hole are ensured. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 is the front view structural schematic diagram of the large-diameter hard sand layer stirring screw drill bit of the present utility model.

[0013] Figure 2 is Figure 1 the schematic cross-sectional structure diagram of A-A.

[0014] Figure 3 is the schematic bottom view structure diagram of the present utility model.

[0015] The reference numerals in the drawings are respectively: 1, drill bit; 2, drill body; 3, spiral blade; 4, long-wing stirring blade; 5, short-wing stirring blade; 6, high-pressure nozzle; 7, external joint; 11, first channel; 21, circular tube; 31, positioning tooth; 71, second channel. Specific embodiments

[0016] The following will introduce the present utility model in detail with reference to the drawings: As shown in the Figures 1 to 3 drawings, the present utility model includes a drill bit 1 and a drill body 2. The drill bit 1 is fixedly connected directly below the drill body 2. A spiral blade 3 for guiding the drilling direction is provided on the outer peripheral wall of the drill bit 1. Long-wing stirring blades 4 and short-wing stirring blades 5 are provided on the outer peripheral wall of the drill body 2. The spiral blade 3, the short-wing stirring blade 5 and the long-wing stirring blade 4 are arranged in sequence from the bottom to the top of the stirring screw drill bit; the short-wing stirring blade 5 is located between the long-wing stirring blade 4 and the spiral blade 3, and the outer diameter of the short-wing stirring blade 5 is smaller than the outer diameter of the long-wing stirring blade 4, the outer diameter of the short-wing stirring blade 5 is larger than the outer diameter of the spiral blade 3, and the outer diameter of the long-wing stirring blade 4 is equal to the hole-forming diameter; a first channel 11 capable of spraying high-pressure water flow is provided on the drill bit 1, and a high-pressure nozzle 6 is installed on the first channel 11, and the high-pressure nozzle 6 is located at the center of the bottom of the drill bit 1; there are a pair of long-wing stirring blades 4 and they are symmetrically distributed along the center of the drill body 2, and there are a pair of short-wing stirring blades 5 and they are symmetrically distributed along the center of the drill body 2; two pairs of blades with different lengths and symmetrically arranged are designed, and combined with the guiding drill bit and the high-pressure nozzle to improve the drilling efficiency and durability, and it is especially suitable for the stirring and pile planting of large-diameter hard sand layers. At the same time, there is one pair of short-wing stirring blades 5 and one pair of long-wing stirring blades 4, which are symmetrically arranged around the drill body 2. During the process of stirring and forming a hole, three-level drilling is realized, and the hole is formed step by step, reducing the hole-forming resistance and improving the footage efficiency.

[0017] The drill bit 1 is conical. The top of the drill bit 1 is fixedly connected to the axial end face of the drill body 2 by welding. The high-pressure nozzle 6 is installed and fixed at the center of the bottom of the drill bit 1, and the first channel 11 is arranged along the axial center of the drill bit 1. A circular tube 21 is installed at the inner center of the drill body 2, and the circular tube 21 is communicated with the first channel 11. An external joint 7 for fixedly connecting the stirring screw drill bit and the drill pipe is installed and fixed on the axial other end face of the drill body 2, and a second channel 71 is provided at the inner center of the external joint 7, and the second channel 71 is communicated with the circular tube 21.

[0018] The bottom of the spiral blade 3 is provided with positioning teeth 31. The positioning teeth 31 are located at the bottom center of the drill bit 1 and protrude from the bottom of the drill bit 1, and the high-pressure nozzle 6 is located inside the positioning teeth 31.

[0019] The working principle of the present utility model is as follows: The drill bit 1 is used to guide the drilling direction. It is equipped with a spiral blade 3 and has a self-drilling function. The spiral structure helps to reduce blockage and improve the drilling speed, thereby completing the first-level drilling; the short-wing mixing blade 5 is used for preliminary cutting and hole expansion, which is the second-level drilling; the diameter of the long-wing mixing blade 4 is the same as the hole-forming diameter. When drilling, it contacts the soil layer that has been broken and hole-expanded, and performs further refinement cutting and shaping, finally completing the third-level drilling. Due to the adoption of three-level drilling and hole formation step by step, the hole-forming resistance is reduced and the service life of the drill bit is extended.

[0020] The above is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed in the present application should be covered by the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A large-diameter hard sand layer stirring screw drill bit, comprising a drill bit (1) and a drill body (2), characterized in that: The drill bit (1) is fixedly connected to the bottom of the drill body (2); a spiral blade (3) for guiding the drilling direction is provided on the outer peripheral wall of the drill bit (1); a long-wing stirring blade (4) and a short-wing stirring blade (5) are provided on the outer peripheral wall of the drill body (2); the spiral blade (3), the short-wing stirring blade (5) and the long-wing stirring blade (4) are arranged in sequence from the bottom to the top of the stirring screw drill bit; the short-wing stirring blade (5) is located between the long-wing stirring blade (4) and the spiral blade (3); the outer diameter of the short-wing stirring blade (5) is smaller than the outer diameter of the long-wing stirring blade (4); the outer diameter of the short-wing stirring blade (5) is larger than the outer diameter of the spiral blade (3); and the outer diameter of the long-wing stirring blade (4) is equal to the hole diameter; the drill bit (1) is provided with a first channel (11) capable of spraying high-pressure water flow, and a high-pressure nozzle (6) is installed on the first channel (11); the high-pressure nozzle (6) is located at the bottom center of the drill bit (1).

2. The large diameter hard sand layer stirring screw drill bit according to claim 1, characterized in that: The drill bit (1) is cone-shaped, the top of the drill bit (1) is fixed to an axial end face of the drill body (2) by welding, the high-pressure nozzle (6) is mounted and fixed on the bottom center of the drill bit (1), and the first channel (11) is arranged along the axial center of the drill bit (1).

3. The large diameter hard sand layer stirring screw drill bit according to claim 2, characterized in that: A circular tube (21) is installed at the inner center of the drill body (2), and the circular tube (21) is connected to the first channel (11).

4. The large diameter hard sand layer stirring screw drill bit according to claim 3, characterized in that: An external joint (7) for fixedly connecting a stirring screw drill bit to a drill rod is mounted on the other axial end surface of the drill body (2), and a second channel (71) is provided at the inner center of the external joint (7), and the second channel (71) is connected to the circular tube (21).

5. The large diameter hard sand layer stirring screw drill bit according to claim 1, characterized in that: The bottom of the spiral blade (3) is provided with a positioning tooth (31), the positioning tooth (31) is located at the bottom center of the drill bit (1) and protrudes from the bottom of the drill bit (1), and the high-pressure nozzle (6) is located on the inner side of the positioning tooth (31).

6. The large diameter hard sand layer stirring screw drill bit according to claim 1, characterized in that: A pair of long-wing stirring blades (4) are provided and are symmetrically distributed along the center of the drill body (2), and a pair of short-wing stirring blades (5) are provided and are symmetrically distributed along the center of the drill body (2).

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