Combined drill bit for cement-soil mixing piles

Abstract

The utility model relates to a combined drill bit for cement soil mixing pile, which comprises: a plurality of center drill rods, which are arranged at intervals, and a plurality of drill rod blades are fixedly installed at the lower sections of the center drill rods at intervals; a plurality of outer sleeve drill rods, which are coaxially rotatably sleeved on the upper sections of the center drill rods; a mixing assembly, which is coaxially fixed at the bottom end of the outer sleeve drill rods, a plurality of mixing outer blades are fixedly installed on the outer side of the mixing assembly at intervals, a plurality of mixing inner blades are fixedly installed on the inner side of the mixing assembly at intervals, the mixing inner blades and the drill rod blades are arranged in a staggered manner; and the mixing outer blades of adjacent mixing assemblies are arranged in a staggered manner. The mixing outer blades and the mixing inner blades of the combined drill bit are responsible for cutting and mixing the soil in the pile body and the surrounding soil, ensuring that most of the area of the mixing pile is forcibly mixed, the mixing range completely covers the mixing pile range, fully mixing the cement slurry and the soil, improving the quality of the mixing pile, and achieving good mixing effect.

Description

Technical Field

[0001] This utility model belongs to the field of mixing pile construction technology, and relates to drill bits for mixing pile construction, especially a combined drill bit for cement-soil mixing piles. Background Technology

[0002] Mixing piles are a common method for foundation treatment and constructing underground water-stop curtains, and are constructed using drill bits. Currently, widely used drill bits are mainly divided into unidirectional mixing drill bits and bidirectional mixing drill bits, each with the following problems:

[0003] 1. Unidirectional mixing drill bit: With fewer mixing blades and larger axial spacing, the cutting effect on the soil is limited, resulting in insufficient mixing of cement slurry and soil. This easily leads to the formation of unmixed "plain soil cores" or cement slurry-rich "cemented lumps" inside the pile, which seriously affects the uniformity and overall strength of the mixing pile. In addition, when constructing a continuous wall of mixing piles, it is necessary to interlock adjacent piles to form a seal. The mixing effect of the unidirectional mixing drill bit in the overlapping area is poor, which can easily form a weak zone for water seepage.

[0004] 2. When the diameter of the mixing pile is large, the soil mixing effect near the blade edge of the traditional bidirectional mixing drill bit is significantly worse. In addition, bidirectional mixing drill bits are mostly cage-type. This structure means that when constructing interlocking mixing piles, such as biaxial mixing piles, one pile can only be constructed first and then the other pile, and the pile spacing is smaller than the pile diameter. Since the construction is not carried out simultaneously, this interlocking is called hard interlocking, which not only easily causes pile deviation, but also results in poor interlocking effect and makes it difficult to guarantee the water-stopping effect. Utility Model Content

[0005] The purpose of this utility model is to overcome the shortcomings of the existing technology and provide a combined drill bit for cement-soil mixing piles that is simple in structure and quick to construct.

[0006] To solve the above problems, the technical solution of this utility model is as follows:

[0007] A combined drill bit for cement-soil mixing piles, comprising:

[0008] Several central drill rods are arranged in parallel at vertical intervals, and several drill rod blades are fixedly installed at intervals on the lower section of each central drill rod.

[0009] Several outer drill pipes are coaxially and rotatably mounted on the upper section of the central drill pipe;

[0010] The mixing components are coaxially rotated and mounted on the lower section of the central drill rod, and fixed to the bottom end of the outer drill rod. Several outer mixing blades are fixedly installed at intervals on the outer surface of the mixing components, and several inner mixing blades are fixedly installed at intervals on the inner surface of the mixing components. The several inner mixing blades and several drill rod blades are staggered.

[0011] The outer blades of adjacent mixing components are staggered.

[0012] In a further embodiment, the stirring range of the inner stirring blades partially overlaps with the stirring range of the drill pipe blades.

[0013] In a further embodiment, the stirring ranges of the outer blades of adjacent stirring components partially overlap.

[0014] In a further embodiment, adjacent stirring components rotate in opposite directions.

[0015] In a further embodiment, the rotation directions of the center drill pipe and the outer drill pipe are opposite.

[0016] In a further embodiment, the rotational speed of the center drill pipe is different from that of the outer drill pipe.

[0017] In a further embodiment, a soil-breaking drill tip is fixedly installed at the bottom end of the central drill rod extending from the mixing assembly.

[0018] In a further embodiment, the outer stirring blade, the inner stirring blade, and the drill pipe blade are all inclined.

[0019] In a further embodiment, the diameter of the stirring assembly is larger than the diameter of the outer drill rod.

[0020] In a further embodiment, the stirring assembly includes several connecting plates, which are evenly distributed circumferentially around the outer drill rod, and are parallel to the central drill rod.

[0021] The top ends of several connecting plates are fixed on the first ring at the bottom end of the outer casing drill rod, and the bottom ends of several connecting plates are bent inward and connected to the second ring. The first ring and the second ring are coaxially rotated and fitted on the central drill rod.

[0022] Several connecting plates have outer stirring blades fixedly mounted on their outer surfaces, and several connecting plates have inner stirring blades fixedly mounted on their inner surfaces.

[0023] Compared with the prior art, the beneficial effects of this utility model are:

[0024] 1. Several drill blades are fixedly installed on the lower section of the central drill rod of this combined drill bit. The drill blades are responsible for cutting and mixing the soil around the drill rod. A mixing assembly is coaxially mounted on the central drill rod. Several inner mixing blades are fixedly installed on the inner side of the mixing assembly, and several outer mixing blades are fixedly installed on the outer side of the mixing assembly. The outer and inner mixing blades are responsible for cutting and mixing the soil inside the pile and the surrounding soil, ensuring that most areas of the mixing pile are forcibly mixed. The mixing range completely covers the mixing pile area, achieving full mixing of cement slurry and soil, improving the quality of the mixing pile, and achieving good mixing effect.

[0025] 2. The stirring component of this combined drill bit includes several first stirring units and second stirring units arranged alternately, where the rotation directions of the first stirring unit and the second stirring unit are opposite. The rotation directions of several central drill pipes are respectively opposite to those of the first stirring unit and the second stirring unit, and the rotation speed of the central drill pipe is higher or lower than that of the first stirring unit and the second stirring unit, so that under the differential reverse drive of the drill pipe blades, the soil in the pile center is powerfully broken and stirred; at the same time, the opposite stirring directions can form a powerful broken stirring at the咬合部位 (bite part), and the kneading effect brought by the reverse rotation is combined to ensure the construction quality of the bite part.

[0026] 3. The stirring component of this combined drill bit is connected to the outer sleeve drill pipe as a whole, and the main body of the stirring component is parallel to the central drill pipe, which can realize the vertical cutting and stirring of the soil, forming a rigid and three-dimensional cage-type stirring framework. Through the internal and external cooperation and two-way shearing stirring method with the central drill pipe, the cement and the soil are extremely evenly mixed, greatly enhancing the stirring effect, ensuring the diameter of the formed pile, and significantly improving the quality of a single pile. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is the front view of a combined drill bit for a cement-soil mixing pile;

[0028] Figure 2 It is the top view of a combined drill bit for a cement-soil mixing pile;

[0029] Figure 3 It is the schematic diagram of a combined drill bit for a cement-soil mixing pile.

[0030] In the figure: 1. Central drill pipe; 11.破土钻尖 (breaking soil drill tip); 12. Drill pipe blade; 2. Outer sleeve drill pipe; 3. Stirring component; 31. Stirring outer blade; 32. Stirring inner blade; 33. First ring; 4. Second ring. DETAILED IMPLEMENTATION MANNER

[0031] It should be noted that the term "咬合部位" in the original text is not clearly defined. You may need to further clarify its specific meaning according to the context for a more accurate translation. Also, the term "破土钻尖" is a literal translation for "11、破土钻尖", and it might be more appropriate to have a more descriptive and accurate name depending on the actual function and design of this part in the drill bit.In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present utility model. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first", "second", etc. may explicitly or implicitly include one or more of such features. In the description of the present utility model, unless otherwise specified, the meaning of "plurality" is two or more.

[0032] Embodiment 1:

[0033] A combined drill bit for a cement-soil mixing pile, as Figures 1 to 3 shown, includes three central drill pipes 1, and the three central drill pipes 1 are arranged at intervals; an outer drill pipe 2 is coaxially sleeved on the upper segment of the central drill pipe 1, and a plurality of drill pipe blades 12 are fixedly installed at intervals on the lower segment of the central drill pipe 1. A破土钻尖11 is fixedly installed at the bottom end of the central drill pipe 1, and the破土钻尖11 is a triangular sheet structure, which is convenient for drilling soil. The central drill pipe 1 and the outer drill pipe 2 are respectively connected to an external driving device, such as a motor, etc., and are adapted to drive the central drill pipe 1 and the outer drill pipe 2 to rotate respectively. The central drill pipe 1 and the drill pipe blade 12 are connected together by welding, or a hoop, or a bolt, or integral forming, etc., for stirring the soil near the central drill pipe 1. The破土钻尖11 and the central drill pipe 1 are connected together by welding, or a hoop, or a bolt, or integral forming, etc., and are used for breaking soil and stirring the pile tip during the drilling process. Preferably, the number of the central drill pipes 1 can be increased or decreased according to the construction requirements; the interval distance between two adjacent central drill pipes 1 is determined according to the use requirements; the size of the破土钻尖11 is adjusted according to the soil quality requirements. In a harder soil layer, the size of the破土钻尖11 should be smaller than that of the stirring component 3, and in a softer soil layer, the size of the破土钻尖11 can be the same as that of the stirring component 3.

[0034] It should be noted that there seems to be an incorrect or incomplete character "破土钻尖11" in the original Chinese text which might affect the accuracy of the translation. You may want to check and correct it in the original for a more precise translation.The bottom end of the outer casing drill pipe 2 is fixedly installed with a stirring component 3. The stirring component 3 is coaxially sleeved outside the central drill pipe 1. The diameter of the stirring component 3 is larger than that of the outer casing drill pipe 2. The bottom end of the stirring component 3 is higher than the破土 drill tip 11; the rotation direction of the central drill pipe 1 is opposite to that of the stirring component 3, and the rotation speed of the central drill pipe 1 is higher or lower than that of the stirring component 3. The stirring component 3 includes two first stirring units and one second stirring unit. The first stirring units and the second stirring unit are arranged alternately, and the rotation direction of the second stirring unit is opposite to that of the two first stirring units. In this embodiment, the second stirring unit is located between the two first stirring units. Preferably, the number of the first stirring units and the second stirring unit can be increased or decreased according to the number of the central drill pipes 1; the first stirring units and the second stirring unit can rotate and stir simultaneously, or can rotate and stir successively according to the construction requirements.

[0035] The bottom end of the outer casing drill pipe 2 is fixedly installed with a first ring 33; both the first stirring unit and the second stirring unit include three strip-shaped connecting plates. The three strip-shaped connecting plates are fixedly installed on the first ring 33 and are evenly distributed circumferentially. The three strip-shaped connecting plates are all parallel to the central drill pipe 1 and vertically cut and stir the soil during rotation to form a three-dimensional stirring, making the stirring more sufficient; the bottom ends of the three strip-shaped connecting plates are bent inward and connected to the second ring 34. Both the first ring 33 and the second ring 34 are coaxially sleeved outside the central drill pipe 1. Preferably, the number of the strip-shaped connecting plates can be increased or decreased according to the construction requirements; the strip-shaped connecting plates and the outer casing drill pipe 2 are fixedly connected together by means of flange, or welding, or bolts, or integral forming, etc.

[0036] A number of stirring inner blades 32 are fixedly installed at intervals on the inner side surface of the strip-shaped connecting plate. The number of the stirring inner blades 32 and the number of the drill pipe blades 12 are arranged staggeredly, and the rotation range of the stirring inner blades 32 partially overlaps with the rotation range of the drill pipe blades 12; a number of stirring outer blades 31 are fixedly installed at intervals on the outer side surface of the strip-shaped connecting plate. The stirring outer blades 31 of the first stirring unit and the stirring outer blades 31 of the second stirring unit are arranged staggeredly, and the rotation range of the stirring outer blades 31 of the first stirring unit partially overlaps with the rotation range of the stirring outer blades of the second stirring unit. As Figure 3 shown, a number of the drill pipe blades 12, a number of the stirring outer blades 31, and a number of the stirring inner blades 32 can all be inclined, and the inclination angle is between 30° and 45°; or as Figure 1 shown, a number of the drill pipe blades 12, a number of the stirring outer blades 31, and a number of the stirring inner blades 32 can all be horizontal. Preferably, the sizes of the first stirring unit, the second stirring unit, the stirring inner blades 32, and the stirring outer blades 31 are related to the diameter of the mixing pile and the biting size, and are adjusted according to the actual construction requirements.

[0037] The working principle of the present utility model is as follows: according to the actual construction requirements, the corresponding number of central drill pipes 1, the first stirring unit and the second stirring unit are set; during construction, a number of central drill pipes 1 are respectively arranged at a number of mixing pile positions, and stirring construction is carried out simultaneously. The破土钻尖 (soil-breaking drill tip) 11 first breaks the soil body, and the outer casing drill pipes 2 respectively drive the first stirring unit and the second stirring unit to rotate, so as to stir the main area of the pile body and ensure the咬合施工效果 (construction effect of the overlapping of mixing piles). During the stirring process, the slurry of the curing material can be conveyed to the soil-breaking drill tip 11 through the channel inside the central drill pipe 1 and sprayed out through the spray holes on the side wall of the central drill pipe 1.

[0038] In addition, it should be understood that although this specification is described according to the embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art. It should be noted that the term "破土钻尖" is a literal translation, and it may be necessary to adjust it according to the specific context to make it more accurate in the actual technical field. Also, "咬合施工效果" is a literal translation and may need to be refined according to the actual meaning in the relevant technical field.

Claims

1. A combined drill bit for cement-soil mixing piles, characterized in that, include: Several central drill rods (1) are arranged in parallel at vertical intervals, and several drill rod blades (12) are fixedly installed at intervals on the lower section of each central drill rod (1). Several outer drill rods (2) are coaxially rotated and fitted onto the upper section of the central drill rod (1); The stirring assembly (3) is coaxially rotated and mounted on the lower section of the central drill rod (1) and fixedly installed at the bottom end of the outer drill rod (2). Several outer stirring blades (31) are fixedly installed at intervals on the outer surface of the stirring assembly (3), and several inner stirring blades (32) are fixedly installed at intervals on the inner surface of the stirring assembly (3). The several inner stirring blades (32) and the several drill rod blades (12) are staggered. The outer stirring blades (31) of adjacent stirring components (3) are staggered.

2. The combined drill bit for cement-soil mixing piles according to claim 1, characterized in that, The stirring range of the inner stirring blade (32) partially overlaps with the stirring range of the drill pipe blade (12).

3. The combined drill bit for cement-soil mixing piles according to claim 2, characterized in that, The stirring ranges of the outer stirring blades (31) of the adjacent stirring components (3) partially overlap.

4. The combined drill bit for cement-soil mixing piles according to any one of claims 1 to 3, characterized in that, The adjacent stirring components (3) rotate in opposite directions.

5. The combined drill bit for cement-soil mixing piles according to claim 4, characterized in that, The rotation direction of the central drill rod (1) is opposite to that of the outer drill rod (2).

6. The combined drill bit for cement-soil mixing piles according to claim 5, characterized in that, The rotational speed of the central drill rod (1) is different from that of the outer drill rod (2).

7. The combined drill bit for cement-soil mixing piles according to any one of claims 1 to 3, characterized in that, A soil-breaking drill tip (11) is fixedly installed at the bottom end of the central drill rod (1) extending from the mixing assembly (3).

8. The combined drill bit for cement-soil mixing piles according to any one of claims 1 to 3, characterized in that, The outer stirring blade (31), the inner stirring blade (32), and the drill rod blade (12) are all inclined.

9. The combined drill bit for cement-soil mixing piles according to any one of claims 1 to 3, characterized in that, The diameter of the stirring assembly (3) is larger than the diameter of the outer drill rod (2).

10. The combined drill bit for cement-soil mixing piles according to any one of claims 1 to 3, characterized in that, The stirring assembly (3) includes several connecting plates, which are evenly distributed around the outer outer drill rod (2) in a circumferential axial direction, and are parallel to the central drill rod (1). The top ends of several connecting plates are fixed on the first ring (33) at the bottom end of the outer casing drill rod (2). The bottom ends of several connecting plates are bent inward and connected together with the second ring (34). The first ring (33) and the second ring (34) are coaxially rotated and fitted on the central drill rod (1). The outer stirring blades (31) are fixedly mounted on the outer side of several of the connecting plates, and the inner stirring blades (32) are fixedly mounted on the inner side of several of the connecting plates.

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