JP2019100126A - Excavation pipe, method of manufacturing excavation pipe and method of excavation ground - Google Patents

Abstract

To provide an excavation pipe capable of suppressing the prolongation of construction period and the increase in construction cost even on a ground containing many relatively large gravel.SOLUTION: An excavation pipe according to one aspect of the present invention comprises a first pipe having a first end and a second end opposite to the first end, and opening at the first end and the second end, an excavation bit located at the first end, and a suction prevention portion disposed at the opening of the first pipe at the first end and provided with the opening. The first pipe has a first inner pipe and a first outer pipe arranged to cover the outer peripheral surface of the first inner pipe at an interval between the outer peripheral surface of the first inner pipe. The size of the opening in the suction prevention portion is smaller than the minimum value of the inner diameter of the first inner pipe.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a drilling pipe, a method of manufacturing the drilling pipe, and a method of drilling a ground.

  Conventionally, as described in Non-Patent Document 1, a reverse circulation rotary method is known as a method of excavating the ground. The drilling pipe used in the reverse circulation rotary method has a first end and a second end opposite to the first end, and the pipe opens at the first end and the second end; And a drill bit disposed at one end. The pipe has an inner pipe and an outer pipe arranged to cover the outer peripheral surface of the inner pipe at a distance between the outer peripheral surface of the inner pipe.

  In the reverse circulation rotary method, water is made to flow between the outer peripheral surface of the pipe and the drilling hole in the direction from the second end toward the first end, and between the outer peripheral surface of the inner pipe and the inner peripheral surface of the outer pipe. The ground is excavated by excavating the ground with an excavating bit while flowing air to the ground and discharging the soil and weirs excavated from the ground with the water through the inner pipe.

Conrad company homepage, July 13, 2017 search, Internet (https://conrad-stanen.nl/en/products/combi-500)

  The reverse circulation rotary method works effectively on a ground that does not contain a large number of weirs or a ground that contains only small weirs. However, for example, in a ground that contains a relatively large number of ridges, such as the ground in Japan, the ridge cut from the ground may clog the inner pipe when it is discharged. If the weir is clogged, it will be necessary to extract the drill pipe from the drilling hole and take out the clogged clog.

  Such a problem can be solved, for example, by thickening the pipe. However, thickening the pipe increases the weight of the drill pipe. When excavating the ground by the reverse circulation rotary method, the excavation pipe is supported by heavy machinery. Also, heavy equipment pulls out the drilling pipe from the drilling hole after the end of drilling. If the weight of the drill pipe increases by thickening the drill pipe according to the size of the weir included in the ground, it is necessary to change the design of the heavy machine according to the weight of the drill pipe. As a result, the construction period will be prolonged and construction costs will increase.

  The present invention has been made in view of the problems of the prior art as described above. More specifically, the present invention is directed to a drilling pipe, a method of manufacturing a drilling pipe, and a ground pipe capable of suppressing an increase in construction period and an increase in construction cost even on a ground including a large number of relatively large ridges. Provide a drilling method.

  A drilling pipe according to an aspect of the present invention has a first end and a second end opposite to the first end, and a first pipe open at the first end and the second end; The drill bit includes a digging bit disposed at the first end, and a suction preventing portion disposed at the opening of the first pipe at the first end and provided with the opening. The first pipe has a first inner pipe and a first outer pipe arranged to cover the outer peripheral surface of the first inner pipe at an interval between the outer peripheral surface of the first inner pipe. The size of the opening in the suction prevention portion is smaller than the minimum value of the inner diameter of the first inner pipe.

  When the ground is excavated by the reverse circulation rotary method using the excavation pipe according to one aspect of the present invention, the diameter of the weir cut from the ground is smaller than the minimum value of the inner diameter of the first inner pipe However, it is difficult to be sucked into the first inner pipe. Therefore, according to the excavating pipe according to one aspect of the present invention, excavating the ground by the reverse circulation rotary method without thickening the first pipe is possible even if the ground contains a large number of relatively large weirs. it can. That is, according to the excavation pipe which concerns on 1 aspect of this invention, even if it is a ground which contains many comparatively large coffins, the extension of construction period and the increase in construction cost can be suppressed.

  In the above-mentioned excavation pipe, the suction prevention part may be constituted by a plurality of wires, and the opening of the suction prevention part may be demarcated by the wire arranged adjacently. In this case, the suction preventing portion can be easily attached at the excavation site.

  In the above-described drill pipe, each of the wires may be fixed to the first inner pipe at one end. Each of the wires may be fixed to the drilling bit at the other end. In this case, it is possible to improve the durability of the suction preventing portion constituted by the wire.

  In the above-described drilling pipe, the opening surface defined by the adjacently disposed wires may intersect a direction orthogonal to the direction from the second end to the first end. In this case, since it becomes easy to detach the soot which was once captured by the suction prevention part from the suction prevention part, the digging efficiency can be improved.

  In the above-mentioned excavation pipe, the size of the opening in the suction prevention portion may be configured to be adjustable by curving the wire. In this case, the size of the opening of the suction preventing portion can be easily adjusted at the excavation site.

  The above-mentioned drilling pipe has a third end and a fourth end which is an end opposite to the third end, and a second pipe which opens at the third end and the fourth end, and a first O-ring And a second O-ring. The second pipe has a second inner pipe and a second outer pipe disposed so as to cover the outer peripheral surface of the second inner pipe at a distance from the outer peripheral surface of the second inner pipe. It is also good. The first inner pipe and the second inner pipe are airtightly connected by the first O-ring, and the first outer pipe and the second outer pipe are airtightly connected by the second O-ring. The third end may be connected. In this case, even when connecting a plurality of pipes, it is possible to suppress a drop in the pressure of air in the pipes.

  In the method of manufacturing a drilling pipe according to one aspect of the present invention, the step of preparing the above-mentioned drilling pipe, the step of performing test drilling of the ground, and suction prevention according to the size of the weir collected from the ground in the test drilling Adjusting the size of the opening in the part by bending the wire.

  According to the method of manufacturing a drilling pipe according to one aspect of the present invention, it is possible to obtain a drilling pipe in which the size of the opening in the suction preventing portion is appropriately adjusted according to the condition of the ground, so the construction period is prolonged. An increase in construction costs can be suppressed.

  In the ground excavating method according to an aspect of the present invention, water is made to flow between the drilling hole and the outer peripheral surface of the first pipe in the direction from the second end toward the first end, and with the outer peripheral surface of the first inner pipe The ground is excavated by the digging bit while flowing air in the direction from the second end to the first end with the inner circumferential surface of the first outer pipe, and soil and weeds excavated from the ground are firstly The steps of discharging through the pipe and adjusting the size of the opening in the suction block by curving the wire when a part of the weir is clogged in the first inner pipe.

  According to the method of excavating the ground according to one aspect of the present invention, the size of the opening of the suction preventing portion is adjusted at the excavation site even when a part of the weir cut out from the ground is clogged. As a result, it is possible to easily cope with the clogging of the weirs, so it is possible to suppress the prolongation of the construction period and the increase of the construction cost.

  According to a drilling pipe according to an aspect of the present invention, a method of manufacturing a drilling pipe according to an aspect of the present invention, and a method of excavating a ground according to an aspect of the present invention And the increase in construction costs can be curbed.

It is a side view of a drilling pipe concerning an embodiment. It is a sectional view of a drilling pipe concerning an embodiment. FIG. 2 is an enlarged view of region III of FIG. 1; It is a front view from the direction IV of FIG. It is process drawing which shows the manufacturing method of the excavation pipe which concerns on embodiment. It is process drawing which shows the excavation method of the ground using the excavation pipe which concerns on embodiment. It is a schematic diagram which shows the reverse circulation rotary construction method using the excavation pipe which concerns on embodiment.

  Embodiments of the present invention will be described with reference to the drawings. In the following drawings, the same or corresponding parts will be denoted by the same reference numerals, and the description thereof will not be repeated.

(Configuration of drilling pipe according to the embodiment)
Hereinafter, the configuration of the drilling pipe 10 according to the embodiment will be described.

  FIG. 1 is a side view of a drilling pipe 10 according to an embodiment. As shown in FIG. 1, the digging pipe 10 has a first pipe 1, a digging bit 2, and a suction preventing portion 3. The drilling pipe 10 further includes a second pipe 4, a first O-ring 5, and a second O-ring 6 (see FIG. 2 for the first O-ring 5 and the second O-ring 6). It may be done. In addition, in FIG. 1, although illustrated about the case where the number of pipes is 2, the number of the pipe which comprises the excavation pipe 10 may be three or more.

  The first pipe 1 has a first end 1a and a second end 1b. The first end 1 a is one end of the first pipe 1. The second end 1 b is the opposite end of the first end 1 a. The first pipe 1 is open at the first end 1 a and the second end 1 b. The central axis of the first pipe 1 is along the direction from the second end 1 b to the first end 1 a.

  FIG. 2 is a cross-sectional view of the drilling pipe 10 according to the embodiment. In addition, illustration of the excavation bit 2 and the suction prevention part 3 is abbreviate | omitted in FIG. The first pipe 1 has a first inner pipe 11 and a first outer pipe 12. The first inner pipe 11 has an inner circumferential surface 11 a and an outer circumferential surface 11 b. The first inner pipe 11 is cylindrical. The first inner pipe 11 is preferably cylindrical. The first outer pipe 12 has an inner circumferential surface 12 a and an outer circumferential surface 12 b. The first outer pipe 12 is cylindrical. The first outer tube 12 is preferably cylindrical. The first inner pipe 11 and the first outer pipe 12 are preferably arranged concentrically around the central axis in a cross-sectional view perpendicular to the direction from the second end 1 b to the first end 1 a.

  The first outer pipe 12 is disposed outside the first inner pipe 11. The first outer pipe 12 is disposed such that the inner circumferential surface 12 a faces the outer circumferential surface 11 b. That is, the first outer pipe 12 is disposed so as to cover the outer peripheral surface 11 b. The first outer pipe 12 is disposed at a distance from the outer circumferential surface 11 b. That is, a space is formed between the inner circumferential surface 12a and the outer circumferential surface 11b. The minimum value of the inner diameter of the first inner pipe 11 is, for example, 150 mm.

  As shown in FIG. 1, the digging bit 2 is attached to the first pipe 1. More specifically, the drilling bit 2 is attached to the first end 1a. The digging bit 2 contacts the ground and digs the ground when the first pipe 1 rotates around the central axis. The tip of the drilling bit 2 is at a position projecting beyond the first end 1 a.

  The suction prevention part 3 is arrange | positioned at the 1st end 1a. The suction prevention unit 3 prevents a part of the weir generated by the excavation bit 2 excavating the ground from being sucked into the first pipe 1.

  FIG. 3 is an enlarged view of region III of FIG. FIG. 4 is a front view from direction IV of FIG. In FIG. 4, the illustration of the drilling bit 2 is omitted. As shown to FIG.3 and FIG.4, it is preferable that the suction prevention part 3 is comprised by the some wire. The number of wires constituting the suction prevention unit 3 is, for example, three. However, the number of wires constituting the suction preventing portion 3 is not limited to this. That is, the number of wires constituting the suction prevention unit 3 may be two or four or more. In addition, in the following example, the suction prevention part 3 shall be comprised by the wire 31, the wire 32, and the wire 33. As shown in FIG.

  Each of the wire 31, the wire 32 and the wire 33 is preferably fixed to the outer peripheral surface of the first pipe 1 (that is, the outer peripheral surface 12 b of the first outer pipe 12) at one end. The fixing of the wires 31, 32 and 33 to the first pipe is preferably performed by welding, for example.

  Each of the wire 31, the wire 32 and the wire 33 is preferably fixed to one another at the other end. The other ends of the wire 31, the wire 32 and the wire 33 are preferably in a position projecting beyond the first end 1 a. Each of the wire 31, the wire 32 and the wire 33 is more preferably fixed to the drilling bit 2 at the other end.

  The wires 31, the wires 32 and the wires 33 are preferably arranged at equal intervals in the circumferential direction of the first pipe 1. The wire 31, the wire 32, and the wire 33 are rod-like members having a plastic deformability that can be bent at a construction site. The wire 31, the wire 32, and the wire 33 are reinforcing bars made of carbon steel, for example.

  The suction preventing portion 3 is provided with an opening 34. The number of openings 34 is preferably multiple. In the example of FIG. 3, three openings 34 are respectively defined by the wires 31 and 32, the wires 32 and 33, and the wires 33 and 31. That is, when the suction prevention part 3 is comprised by several wires, the opening 34 is defined by the wire arrange | positioned adjacently.

  The size of the opening 34 is smaller than the minimum value of the inner diameter of the first inner pipe 11. When the drill pipe 10 has the second pipe 4, the size of the opening 34 is smaller than the minimum value of the inner diameter of the second inner pipe 41. That is, the size of the opening 34 is smaller than the minimum value of the inner diameter of the inner pipe of the pipe constituting the drilling pipe 10. When the opening 34 is defined by a wire, the size of the opening 34 is defined by the diameter of the inscribed circle of the area defined by the wire.

  The size of the opening 34 can be adjusted by curving the wire 31, the wire 32 and the wire 33 when the suction preventing portion 3 is configured by the wire 31, the wire 32 and the wire 33. More specifically, by bending the wires 31, 32 and 33 toward the central axis of the first pipe 1, the size of the opening 34 can be reduced.

  The opening surface defined by the wires 31 and 32, the opening surface defined by the wires 32 and 33, and the opening surface defined by the wires 33 and 31 have the direction of the central axis of the first pipe 1 (second end It is preferable to intersect a direction perpendicular to the direction from 1b to the first end 1a). That is, the opening surface defined by the wires 31 and 32, the opening surface defined by the wires 32 and 33, and the opening surface defined by the wires 33 and 31 are orthogonal to the direction of the central axis of the first pipe 1. Preferably not.

  As shown in FIG. 1, the second pipe 4 has a third end 4 a and a fourth end 4 b. The third end 4 a is one end of the second pipe 4. The fourth end 4 b is the opposite end of the third end 4 a. The second pipe 4 is open at the third end 4 a and the fourth end 4 b. The central axis of the second pipe 4 is along the direction from the third end 4a to the fourth end 4b. The third end 4a is connected to the second end 1b. The central axis of the second pipe 4 is preferably connected to the first pipe 1 so as to coincide with the central axis of the first pipe 1.

  As shown in FIG. 2, the second pipe 4 has a second inner pipe 41 and a second outer pipe 42. The second inner pipe 41 has an inner circumferential surface 41 a and an outer circumferential surface 41 b. The second inner pipe 41 is cylindrical. The second inner pipe 41 is preferably cylindrical. The second outer pipe 42 has an inner circumferential surface 42 a and an outer circumferential surface 42 b. The second outer pipe 42 is cylindrical. The second outer tube 42 is preferably cylindrical. The second inner pipe 41 and the second outer pipe 42 are preferably arranged concentrically around the central axis in a cross-sectional view perpendicular to the direction from the fourth end 4 b toward the third end 4 a.

  The second outer pipe 42 is disposed outside the second inner pipe 41. The second outer pipe 42 is disposed such that the inner circumferential surface 42 a faces the outer circumferential surface 41 b. That is, the second outer pipe 42 is disposed so as to cover the outer peripheral surface 41 b. The second outer pipe 42 is disposed at a distance from the outer circumferential surface 41 b. That is, a space is formed between the inner circumferential surface 42a and the outer circumferential surface 41b.

  The first inner pipe 11 and the second inner pipe 41 are airtightly connected by the first O-ring 5. The first outer pipe 12 and the second outer pipe 42 are airtightly connected by the second O-ring 6. More specifically, the first inner pipe 11 is inserted into the second inner pipe 41, and the first O-ring 5 is disposed between the inner peripheral surface 11a and the outer peripheral surface 41b, thereby making the first inner The pipe 11 and the second inner pipe 41 are airtightly connected. Further, in a state where the first outer pipe 12 is inserted into the second outer pipe 42, the first outer pipe 12 and the second outer pipe 42 are connected by screws, and between the inner circumferential surface 12a and the outer circumferential surface 42b The first outer pipe 12 and the second outer pipe 42 are airtightly connected by arranging the second O-ring 6 in the second. The first O-ring 5 may be disposed between the outer circumferential surface 11b and the inner circumferential surface 41a, and the second O-ring 6 is disposed between the outer circumferential surface 12b and the inner circumferential surface 42a. May be

(Method of Manufacturing Drilling Pipe According to Embodiment)
Below, the manufacturing method of the excavation pipe 10 which concerns on embodiment is demonstrated.

  FIG. 5: is process drawing which shows the manufacturing method of the excavation pipe 10 which concerns on embodiment. As shown in FIG. 5, the method of manufacturing the digging pipe 10 includes a preparation step S1, a test digging step S2, and an opening adjustment step S3.

  In the preparation step S1, preparation of the drilling pipe 10 is performed. In the test drilling step S2, test drilling of the ground is performed. In the test drilling step S2, a weir is collected from the ground. More specifically, in the test drilling step S2, test drilling is performed using a test drilling drill pipe. The test digging pipe has a pipe including an inner pipe and an outer pipe, and a drill bit attached to one end of the pipe. The minimum value of the inner diameter of the inner pipe used for the test drilling pipe is smaller than the minimum value of the inner diameter of the first inner pipe 11. For example, the minimum value of the inner diameter of the inner pipe used for the test drilling pipe is 80 mm.

  By carrying out test drilling of the ground by the reverse circulation rotary method using the drilling pipe for test drilling, a part of the weir cut out from the ground is clogged with the inner pipe of the drilling pipe for test drilling. The soot stuck in the inner pipe of this test drilling pipe is sampled and its size is measured.

  In the opening adjustment step S3, the size of the opening 34 of the suction preventing portion 3 is adjusted in accordance with the size of the crucible collected in the test digging step S2. According to the inventors' rule of thumb, the maximum value of the size of the weir cut out from the rock is about 1 to 3 times the size of the weir collected in the test drilling step S2 (hereinafter referred to as a predetermined coefficient) Often there is. In the opening adjustment step S3, the size of the opening 34 is appropriately determined, for example, in consideration of such a predetermined coefficient. By the above, manufacture of drilling pipe 10 concerning an embodiment is completed.

(Excavation method of the ground using the excavation pipe according to the embodiment)
Below, the excavation method of the ground using the excavation pipe 10 which concerns on embodiment is demonstrated.

  FIG. 6 is a process chart showing a method of excavating the ground using the excavation pipe 10 according to the embodiment. As shown in FIG. 6, the method of excavating the ground using the excavation pipe 10 includes an excavation step S4 and an opening readjustment step S5.

  FIG. 7 is a schematic view showing a reverse circulation rotary method using the excavation pipe 10 according to the embodiment. As shown in FIG. 7, in the excavation process S4, excavation of the ground is performed using the excavation pipe 10. More specifically, water W is supplied between the outer peripheral surface of the drilling pipe 10 and the inner wall surface of the drilling hole H. The water W flows in the direction from the second end 1 b to the first end 1 a. The drilling hole H is, for example, a heat source well.

  Air A is supplied between the outer peripheral surface 11 b of the first inner pipe 11 and the inner peripheral surface 12 a of the first outer pipe 12. Air A is supplied in a direction from the second end 1 b to the first end 1 a. The air A is supplied, for example, by a compressor (not shown).

  The drill bit 2 drills the bottom of the drill hole H by rotating the drill pipe 10 around the central axis. In this way, gravel and earth and sand are scraped from the ground. The weir and soil are lifted by the air A together with the water W and discharged through the first inner pipe 11. At this time, since the soot which is larger than the minimum value of the inner diameter of the first inner pipe 11 does not easily pass through the opening 34 of the suction preventing portion 3, it hardly enters the inside of the first pipe 1.

  During the excavation process S4, a part of the weir cut out from the ground may clog the first inner pipe 11. In this case, the size of the opening 34 is adjusted in the opening readjustment step S5. For example, by bending the wire 31, the wire 32, and the wire 33, the size of the opening 34 is adjusted. After the opening readjustment step S5 is completed, the digging step S4 is resumed.

(Excavating pipe according to the embodiment, manufacturing method of the excavating pipe according to the embodiment and effect of excavating method of ground using the excavating pipe according to the embodiment)
Below, the effect of the excavation pipe 10 which concerns on embodiment, the manufacturing method of the excavation pipe 10 which concerns on embodiment, and the excavation method of the ground using the excavation pipe 10 which concerns on embodiment is demonstrated.

  When a weir larger than the minimum value of the inner diameter of the first inner pipe 11 intrudes into the inside of the excavating pipe 10, the weir may be clogged in the first inner pipe 11. However, in the digging pipe 10, the size of the opening 34 of the suction preventing portion 3 is smaller than the minimum value of the inner diameter of the first inner pipe 11. Therefore, in the drilling pipe 10, a weir larger than the minimum value of the inner diameter of the first inner pipe 11 is difficult to intrude into the inside of the drilling pipe 10.

  Therefore, according to the digging pipe 10, it is possible to prevent clogs cut from the ground from being clogged in the digging pipe 10 without thickening the first pipe 1 (without increasing the weight of the digging pipe 10 significantly). As a result, the construction period can be prolonged and the construction cost increase can be suppressed.

  When the suction prevention part 3 is comprised by the some wire, the suction prevention part 3 can be attached to the 1st pipe 1 by methods, such as welding. Therefore, in this case, the suction preventing portion 3 can be easily attached at the drilling site.

  When each of the wires constituting the suction preventing portion 3 is fixed to the first end 1a at one end and fixed to the digging bit 2 at the other end, each of the wires constituting the suction preventing portion 3 is firmly fixed Be done. Therefore, in this case, the durability of the suction preventing portion 3 can be improved.

  As described above, the weir cut out of the ground is lifted by the air A along the direction from the first end 1a to the second end 1b. Therefore, when the opening surface defined by the wire constituting the suction prevention portion 3 is orthogonal to the direction of the central axis of the first pipe 1, the suction force by the air A is trapped at the weirs captured by the opening 34. Acts strongly. Therefore, it is difficult for the weir captured in the opening 34 to separate from the opening 34, and there is a possibility that the opening 34 may be blocked. As a result, the discharge efficiency of soot, earth and sand, etc. may be reduced, and the digging efficiency may be reduced.

  In the case where the opening surface defined by the wire forming the suction preventing portion 3 intersects with the direction orthogonal to the direction from the second end 1 b toward the first end 1 a (that is, the opening surface is the center of the first pipe 1 The suction force by the air A acting on the weir captured in the opening 34 is relatively weak (if not orthogonal to the direction of the axis). Therefore, it is easy for the weir captured in the opening 34 to be detached, and the opening 34 is not easily blocked by the weir. Therefore, in this case, the drilling efficiency can be improved.

  When the suction prevention part 3 is comprised by several wires, the opening 34 is demarcated by the wire arrange | positioned adjacently. Therefore, the size of the opening 34 can be easily adjusted by bending the wire. Therefore, in this case, the size of the opening 34 can be appropriately adjusted at the excavation site according to the condition of the ground.

  The drilling pipe 10 further includes a second pipe 4, a first O-ring 5 and a second O-ring 6, and the first inner pipe 11 and the second inner pipe 41 are airtightly sealed by the first O-ring 5. When the second end 1 b and the third end 4 a are connected by connecting the first outer pipe 12 and the second outer pipe 42 airtightly by the second O-ring 6, Even in the case of connecting a pipe, it is possible to suppress a drop in the pressure of air A in the pipe.

  According to the method of manufacturing the drilling pipe 10 according to the embodiment, the drilling pipe 10 in which the size of the opening 34 is appropriately adjusted can be obtained according to the condition of the ground, so the construction period is prolonged and the construction cost is increased. Can be suppressed.

  According to the method of excavating the ground using the excavating pipe 10 according to the embodiment, even if a part of the weir cut out from the ground is clogged, the wire constituting the suction preventing portion 3 at the excavating site By curving the opening 34 and adjusting the size of the opening 34, it is possible to easily cope with the clogging of the weir, so it is possible to suppress the prolongation of the construction period and the increase of the construction cost.

  It should be understood that the embodiment disclosed this time is illustrative in all points and not restrictive. The scope of the present invention is indicated not by the embodiments described above but by the claims, and is intended to include the meanings equivalent to the claims and all modifications within the scope.

  The above embodiments are advantageously applied to a drilling pipe for reverse circulation rotary construction.

  A air, H drilling hole, W water, 10 drilling pipe, 1 first pipe, 1a first end, 1b second end, 11 first inner pipe, 11a inner peripheral surface, 11b outer peripheral surface, 12 first outer pipe, 12a inner circumferential surface, 12b outer circumferential surface, 2 drilling bit, 3 suction preventing portion, 31, 32, 33 wire, 34 opening, 4 second pipe, 4a third end, 4b fourth end, 41 second inner pipe, 41a Inner peripheral surface, 41b outer peripheral surface, 42 second outer pipe, 42a inner peripheral surface, 42b outer peripheral surface, 5 first O ring, 6 second O ring, S1 preparation process, S2 test drilling process, S3 opening adjustment process , S4 drilling process, S5 opening readjustment process.

Claims (8)

A first pipe having a first end and a second end opposite to the first end, and opening at the first end and the second end;
A drilling bit disposed at the first end;
And a suction prevention portion disposed at an opening of the first pipe at the first end and provided with an opening,
The first pipe has a first inner pipe and a first outer pipe arranged to cover the outer peripheral surface of the first inner pipe at a distance between the first inner pipe and the outer peripheral surface of the first inner pipe. And
The size of the opening in the suction prevention portion is a digging pipe smaller than the minimum value of the inner diameter of the first inner pipe. The suction prevention unit is constituted by a plurality of wires,
The drilling pipe according to claim 1, wherein the opening of the suction prevention part is delimited by the wire arranged adjacently. Each of the wires is fixed at one end to the first end,
The drilling pipe according to claim 2, wherein each of the wires is fixed at the other end to the drilling bit.   The excavating pipe according to claim 2 or 3, wherein an open surface defined by the wires disposed adjacent to each other intersects a direction orthogonal to a direction from the second end toward the first end.   The excavation pipe according to any one of claims 2 to 4, wherein the size of the opening in the suction preventing portion is configured to be adjustable by curving the wire. A second pipe having a third end and a fourth end opposite to the third end, and opening at the third end and the fourth end;
With the first o-ring,
And a second o-ring,
The second pipe has a second inner pipe and a second outer pipe arranged to cover the outer peripheral surface of the second inner pipe at a distance between the second inner pipe and the outer peripheral surface of the second inner pipe. And
The first inner pipe and the second inner pipe are airtightly connected by the first O-ring, and the first outer pipe and the second outer pipe are airtightly connected by the second O-ring. The drilling pipe according to any one of claims 1 to 5, wherein the second end and the third end are connected. A method of manufacturing the drilling pipe according to any one of claims 2 to 5, wherein
Preparing the drilling pipe;
A step of conducting a test excavation of the ground,
Adjusting the size of the opening in the suction preventing portion by curving the wire in accordance with the size of a weir collected from the ground in the test drilling. It is an excavating method of the ground performed using said drilling pipe according to any one of claims 2 to 5, wherein
Water is allowed to flow from the second end toward the first end between the drilling hole and the outer peripheral surface of the first pipe, and the outer peripheral surface of the first inner pipe and the inner peripheral surface of the first outer pipe Between the second end and the first end while flowing air in a direction from the second end to the first end, excavating the ground with the digging bit, and discharging the soil and weeds excavated from the ground through the first inner pipe together with the water The process to
And adjusting the size of the opening in the suction preventing portion by curving the wire when part of the weir is clogged in the first inner pipe.

Images