Directional soil coring and sampling equipment and method

Abstract

The invention discloses a horizontal directional soil coring and sampling device and a horizontal directional soil coring and sampling method. By means of the invention, the position of the desired soil sample (201, 301) is determined and a drilling curve is drawn from the inlet pit (30). A drill tube (136) is driven into the drill bit along a drilling curve to create a drill guide path (140); the drill guide path (140) is then enlarged to a drilling path (150) by a forward reamer (160). In one embodiment, a coring head (210) and a soil extractor (270) are driven into a borehole path (150) to obtain an undisturbed soil sample (201). In another embodiment, an outer tube (336) is driven along a borehole path (150) by a coring head (310), and a rope soil extractor (370) is fed down into the inner bore of the outer tube to obtain an undisturbed soil sample (301).

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] The present invention claims priority from Singapore patent application no. 10202204047U filed on April 19, 2023, the entire disclosure of which is incorporated herein by reference. Technical Field

[0003] The present invention relates to an apparatus and method for directional soil coring and sampling. In particular, the present invention relates to forward directional drilling for obtaining subsurface soil samples. Background Art

[0004] The conventional method of directional coring drilling (core drilling) involves maneuvering a drill bit into the ground to create a guide path according to a planned trajectory for mining minerals or exploring for oil and gas; a core sample of the soil (core sample) is then collected, for example, for soil analysis at the end of the planned trajectory. For this method to work, the soil must be hard enough to provide different reaction forces at the steerable drill bit so that the drill bit can be steered along the planned trajectory; therefore, it is not suitable for soft soils. In addition, the radius of curvature of the planned trajectory is usually in the range of several kilometers; in an urban built environment, there are space constraints, so this conventional directional coring drilling is not suitable for use in an urban environment.

[0005] In urban environments, another traditional method called horizontal directional drilling (HDD) has been used, for example, by contractors to lay pipelines. This method enables the installation of pipelines and utilities beneath obstacles such as roads, rivers, buildings, etc., without the need to remove or relocate these above-ground obstacles. HDD also requires a guide drill path; typically, such a drilling path usually consists of straight tangents and long radius arcs, with the guide drill path starting from an entry point to a relative exit point located on the other side of the ground. In practice, the guide drill path is formed by actuating the pilot drill along a planned trajectory, and the guide drill path is then enlarged by back or reverse drilling, that is, the drilling head is actuated to move along the guide drill path from the exit point to the entry point. This method does not allow the extraction of core soil samples along the guide drill path.

[0006] It can be seen that there is a need to provide another directional drilling (boring) apparatus and method for performing underground directional soil coring and soil sampling. The underground soil can be relatively soft or relatively hard. Summary of the invention

[0007] A simplified overview is given below to provide a basic understanding of the present invention. This overview is not an extensive summary of the present invention, nor is it intended to identify key features of the present invention. Instead, it is presented in a summarized form as a prelude to the detailed description below.

[0008] The present invention seeks an apparatus and method for subsurface soil drilling, soil coring and soil sampling. Preferably, the apparatus and method are suitable for obtaining undisturbed soil samples in soft and hard grounds.

[0009] In one embodiment, the present invention provides a device for directional soil drilling, soil coring and soil sampling, which includes: a manipulable drill bit, which can be connected to the end of a drill pipe, and the manipulable drill bit and the drill pipe can be rotated by a drill pipe machine to form a guide drill path according to a predetermined curve; and a forward reamer, which can be connected to the end of the drill pipe at the distal end, and the forward reamer can be rotated to expand the guide drill path to form a drilling path with a predetermined aperture; wherein the drill pipe is made of an aluminum pipe with a predetermined length and outer diameter, and the drill pipe can be extended into a series of multiple drill pipes, and a male threaded joint (PSC) is formed at one end of each drill pipe, and a matching female threaded joint (BSC) is formed at the opposite other end of each drill pipe.

[0010] Preferably, the forward reamer comprises three regions: a stem region, a conical region and a guide region, the guide region being located in a forward position and formed with a diameter substantially matching the diameter of the guide path. Preferably, the guide region is configured as an elongated cylindrical shape, and an abrasive is deposited at the front tip of the guide region. Preferably, the guide region comprises two parts, the two parts being joined by a male threaded joint (PSC) of a predetermined size and a matching female threaded joint (BSC), the PSC and BSC allowing the front tip to be detachably replaced when the abrasive wears.

[0011] Preferably, the conical region comprises: a front conical region, a middle cylindrical region and a rear conical region. Preferably, the cone angle subtended by the front conical region is smaller than the cone angle subtended by the rear conical region. Preferably, a plurality of spiral bands of abrasive are formed on the conical surface of the front conical region. Preferably, the forward reamer further comprises an internal longitudinal hole, the internal longitudinal hole leading to outlets formed on the front conical region and the rear conical region, the outlet on the front conical region being located between the spiral bands of abrasive. Preferably, the cylindrical surface of the middle cylindrical region is formed by a cylindrical band of abrasive or hard facing material.

[0012] In another embodiment, the apparatus further comprises a coring head engaged with a subassembly of a soil extractor, the subassembly of the soil extractor being threadably connectable to the drill pipe.

[0013] Preferably, the soil extractor comprises: a split mold for accommodating a soil sample; or, the soil extractor comprises: an integral mold; and a longitudinal sleeve, the longitudinal sleeve being arranged in the integral mold to accommodate the soil sample. Preferably, the soil extractor further comprises: a sleeve joint; and a stabilizing device, the stabilizing device being threadably connected to the sleeve joint; preferably, both ends of the sleeve joint are formed with a female threaded joint (BSC); preferably, the stabilizing device is substantially configured as a cylindrical shell having two spaced-apart cylindrical bands of abrasive having a predetermined extension diameter D1.

[0014] In another embodiment, the above-mentioned device further comprises: a series of connected outer tubes, the series of connected outer tubes are used to arrange the drilling path and have the coring head attached to the end of the outer tube; and a rope soil extractor, the rope soil extractor can be received in the series of outer tubes, and the lower end of the rope soil extractor is equipped with a coring tube for receiving a soil sample. Preferably, the coring tube further comprises: a longitudinally split sleeve, the longitudinally split sleeve is used to receive the soil sample.

[0015] Preferably, the coring head is provided with a ring of cutting edges consisting of abrasive; the ring of abrasive is arranged in a plurality of sectors. Preferably, the abrasive is formed by coating, depositing, impregnating, welding or brazing the abrasive onto the coring head.

[0016] In another embodiment, the present invention provides a method for soil coring and soil sampling, which includes: determining an underground location for soil sampling; drawing a drilling curve from an entry pit to the underground location for soil sampling; guiding drilling along the drilling curve using a maneuverable drill bit attached to the end of a drill pipe, the drill pipe being extended during the drilling process; retrieving the drill pipe and the drill bit to the entry pit, replacing the drill bit with a forward reamer, and driving the drill pipe to expand the guide drilling path to form a borehole path; retrieving the drill pipe and the forward reamer to the entry pit, replacing the forward reamer with a coring head and a soil extractor, and driving the coring head and the soil extractor into the borehole path using the drill pipe to obtain a soil sample; and retrieving the drill pipe, the coring head, the soil extractor, and the soil sample from the underground location.

[0017] In another embodiment of the above method, after forming the drilling path, the method also includes: driving an outer tube having a coring head at the end, and extending the outer tube so that the coring head reaches the end of the drilling path; and sending a rope soil extractor downward into the inner hole of the outer tube in series, rotating the outer tube to perform soil coring, and after receiving the soil sample in the coring tube connected to the soil extractor, retrieving the rope soil extractor and the soil sample from the underground location. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The present invention will be described by way of non-limiting embodiments thereof with reference to the accompanying drawings, in which:

[0019] FIG1 shows a conventional horizontal directional drilling system using reverse drilling to enlarge the drill path;

[0020] Figure 2 A horizontal directional drilling device using forward (forward) hole expansion according to an embodiment of the present invention is shown;

[0021] Figure 3 Shows Figure 2 Horizontal directional drilling method for soil coring and soil sampling as shown;

[0022] Figure 4 A forward reamer for creating a drilling path by forward reaming of a pilot drill path according to an embodiment of the present invention is shown;

[0023] Figure 5 A coring head having a soil extractor for obtaining a soil sample according to another embodiment of the present invention is shown;

[0024] Figure 6 Shows Figure 5 The arrangement of abrasives at the coring head is shown;

[0025] Figure 7 An assembly diagram of a split mould (separate mould, combined mould, split mould, breaking mould, split mould) forming part of a soil extractor is shown, and Figure 8 and Fig. 9 The split mold is shown when it is disassembled into two halves;

[0026] Fig.10 and 11 Shown for assembly Figure 8 A pair of pins and holes in the two halves of the split mold are shown to align the locking mechanism;

[0027] FIG. 12 shows the drilling path curve (profile) at test site #1 where the soil is soft; Fig.13 A soil sample obtained at Site #1 using the above-mentioned split mold is shown;

[0028] Fig.14 The drilling path curve at test site #2 with harder soil is shown; in addition, Fig.14 Also shown is a drill guide path plotted using a pitch setting for steering the drill bit; Fig.15 shows a soil sample obtained at Site #2 using the above-described split mold; and

[0029] Fig.16 A wireline soil coring extractor according to another embodiment of the present invention is shown. Fig.17 and 18 Shows Fig.16 Two enlarged images of . DETAILED DESCRIPTION

[0030] One or more specific and alternative embodiments of the present invention will now be described with reference to the accompanying drawings. However, it will be apparent to those skilled in the art that the present invention may be practiced without these specific details. Some details may not be described in detail in order not to obscure the present invention. For ease of reference, a common reference number or series of numbers will be used throughout the accompanying drawings when referring to the same or similar features that are common to the accompanying drawings. In the following description, forward refers to the direction in which a drill guide path or a borehole path is being drilled or bored, and backward or reverse refers to the direction opposite to the drilling or boring.

[0031] FIG. 1 is a simplified diagram showing a known conventional horizontal directional drilling system 1, which is provided as the background technology of the present invention. As shown in FIG. 1 , an underground pipeline 44 will be laid below the ground 10, which has some surface obstacles or land structures, such as buildings 20, roads, rivers, etc. The planned underground trajectory of the pipeline is drawn between an entry pit 30 and an exit pit 32. Then, a rotating drill pipe device 34 is positioned at the entry pit 30 to drive a drill pipe 36 provided with a drill bit (not shown in FIG. 1 ) into the ground; then, when the drill bit is driven into the ground along the planned underground trajectory to form a guide drilling path 40, the drill pipe 36 is continuously connected in series until the drill bit reaches the exit pit 32. The drill pipe 36 is made of steel pipe and is joined by a typical threaded connection, which is referred to in this specification as a female box screw connection BSC and a matching male pin screw connection PSC; generally, the length of the drill pipe 36 is substantially 4 m; as an example related to the present invention, the outer diameter of the drill pipe 36 is substantially 70 mm (or substantially 2.875 inches), and the inner bore of the drill pipe 36 is substantially 55 mm. During horizontal directional drilling, drilling mud is pumped through the inner bore of the drill pipe 36 to lubricate the drill bit; during pilot drilling, the drilling mud is returned to the entry pit 30 through the annular space between the hole of the pilot drilling path 40 and the outer diameter of the drill pipe 36; the drilling mud can be reprocessed and reused. Then, at the exit pit 32, the end of the drill pipe 36 is reconnected to the end of the backward drill 42 and the pipeline 44. By rotating the drill pipe 36 and pulling it back to the drilling equipment 34 (in the so-called reverse drilling process), the drill guide path 40 is enlarged to form the drilling path 41; at the same time, by retrieving the drill pipe 36, the pipe 44 is continuously pulled into the drilling path 41, and after the pipe 44 appears at the entry pit 30, the reverse drilling process stops.

[0032] Figure 2 1 is a simplified diagram showing a system of horizontal directional drilling (HDD) equipment 100 or equipment components according to an embodiment of the present invention. Figure 2 In the embodiment of the present invention, a surface obstacle or land structure such as a building 20 is shown as being located on the ground surface 10. As with the conventional HDD described above, a planned underground trajectory for coring the underground soil is drawn from an entry pit 30. A rotary drilling device 34 is then positioned at the entry pit 30 to drive a non-magnetic drill bit ( Figure 2The drill pipe 136 (not shown) follows the planned trajectory; then, when the drill bit is rotated and pushed into the ground along the planned underground trajectory, the drill pipes 136 are sequentially connected in series to form a guide drilling path 140, so as to reach the desired underground position, at which the soil is cored to obtain a soil sample; the drill pipe 136 is made of an aluminum pipe, for example, the length of the drill pipe 136 is basically 1.8-2m, the outer diameter of the drill pipe 136 is basically 70mm (or basically 2.875 inches), and the inner hole of the drill pipe 136 is basically 55mm. Like conventional HDDs, the ends of these drill pipes 136 are also formed with female threaded joints BSC and matching male threaded joints PSC; in the following description, the BSC and PSC of associated sizes are used for threaded connections on the components used in the present invention. Drilling mud, such as bentonite mud, is pumped through the inner hole of the drill pipe 136 to lubricate the drill bit and move drill cuttings to the entry pit 30. After the guide drill path 140 is formed, for example, with a diameter of substantially 70 mm, the drill pipe 136 and the drill bit are taken into the entry pit 30. Then, the drill bit (e.g., Figure 2 As shown), Figure 3 As shown, the drill pipes 136 are sequentially extended in series, driven in rotation and pushed along the guide drill path 140 to expand the guide drill path 140 to form a borehole path 150 of a desired diameter (e.g., approximately 100 mm), thereby reaching a desired location to collect a soil sample 201; the drill pipes 136 are then successively retracted together with the forward reamer 160; at the entrance pit 30, the forward reamer 160 is replaced by the coring head 210 and the soil extractor assembly 270 in series (e.g., Figure 3 ); by extending and driving the drill pipe 136 until the coring head 210 reaches the end of the drilling path 150 to collect the desired soil sample 201, the coring head 210 and the soil extractor assembly 270 are rotated and driven along the drilling path 150. For example, at the end of the drilling path 150, the drill pipe 136 is driven an additional distance of substantially 200 mm or more to obtain the soil sample 201 located at the end of the drilling path 150. In the following description Figure 4-11 The soil coring process will become clearer when

[0033] like Figure 2As shown, the guide drill path 140 consists of substantially straight sections; two straight sections may be joined by an intermediate curved section having a predetermined radius of curvature, for example, of the order of tens of meters; considering that the drill pipe 136 of the present invention made of aluminum tube is more elastic or flexible, the radius of curvature of the curved section of the guide drill path 140 is significantly lower than the radius of curvature formed using the conventional steel drill pipe 36; for the conventional steel drill pipe 36, the radius of curvature is in the range of several kilometers. In order to drill the straight section of the guide drill path 140, the drill pipe 136 is rotated at a relatively high speed; when a change of direction is required, the drilling speed is temporarily stopped (drilling is temporarily stopped) before continuing to drill the continuous straight section of the guide drill path 140, the drill pipe 136 is oriented, and then it can be gradually pushed to follow the directional blades provided on the guide drill head. In another embodiment, when drilling through soft soil, the directional blades can be adjusted at a steeper pitch angle to achieve a change of direction.

[0034] like Figure 3 As shown, the HDD drilling process 200 of the present invention includes three processes, namely, (1) a pilot drilling process, (2) a forward hole expansion process, and (3) a soil coring process. As will be understood, in the present invention, the soil coring process is performed by a soil extractor 270 or a rope soil extractor 370. Now, referring to Figure 4 To describe the forward hole expansion process. Figure 4 A forward reamer 160 is shown according to an embodiment of the present invention. Figure 4As shown, the forward reamer 160 is composed of three regions, namely, a stem region 162, a conical region 164, and a guide region 166. The guide region 166 is rectangular and elongated, and its diameter is substantially equal to the diameter of the guide drill path 140. Preferably, the guide region 166 is composed of two parts 167 and 168, which are threadedly connected to a female threaded joint (BSC) and a male threaded joint (PSC) of associated sizes; the part 168 is located at the tip of the guide region 166, and its front tip is covered with an abrasive 180a; preferably, the abrasive 180a can be made of tungsten carbide, industrial diamond or similar hard abrasives to reduce wear when the forward reamer 160 is rotated and pushed to expand the guide drill path 140. When the abrasive 180a is worn, the tip part 168 can be replaced with a new component. The conical region 164 is composed of a middle cylindrical region 170, a front conical region 172, and a rear conical region 174. The cone angle subtended by the front conical region 172 is smaller than the cone angle subtended by the rear conical region 174, which means that the conical surface defined by the front conical region 172 is longer than the rear cone surface at the rear conical region 174; the diameter of the front conical region 172 at the guide region 166 gradually transitions to the diameter D at the cylindrical region 170; for example, the diameter D is substantially 100 mm. In one embodiment, the conical surface of the front conical region 172 has a plurality of abrasive bands 180b spirally formed thereon; the number of the abrasive bands 180b may be two or more. At the cylindrical region 170, two or more spaced circumferential abrasive belts 180c are provided thereon; like the abrasive 180a, the abrasive belts 180b, 180c may be made of tungsten carbide, industrial diamond or similar hard abrasives; as an alternative to the abrasive belts 180c, a circumferential band of hard facing material may be formed on the cylindrical portion 170; for example, when the forward reamer 160 is made of carbon steel or alloy steel, the circumferential hard facing band may be formed by carburizing or nitriding. Extending from the rear conical region 174 is the stem region 162; the stem region 162 has a female threaded joint BSC for threading into a male threaded joint PSC located at the end of the associated drill pipe 136.

[0035] Return to reference Figure 4, there is an inner hole d formed along the longitudinal axis of the forward reamer 160; through the inner hole d, drilling mud is injected into the forward reamer 160 through the drill pipe 136, and flows out through the outlets 176, 177 respectively located on the front cone surface (front cone surface) 172 and the rear cone surface (rear cone surface) 174, so as to be used for lubrication during the reaming process. There are three outlets 177 on the rear cone surface 174, which are equally spaced at 120 degrees, for example, with a diameter of substantially 19 mm. The number of outlets 177 located at the rear cone surface 174 is kept relatively less than the number of outlets 176 located at the front cone surface 172, so as to deliver sufficient drilling mud to the front area of ​​the forward reamer 160 during forward reaming; with such a structure of the outlets 176, 177, a small part of the supplied drilling mud flows out through the outlet 177 to help clean the drill cuttings and make them flow back to the inlet pit 30. Meanwhile, when the forward reamer 160 operates, drill cuttings and drilling mud flow through the space between the forward reamer 160 and the drilling path 150 , and eventually flow back to the entry pit 30 .

[0036] After the pilot drill path 140 is enlarged into the borehole path 150 by operating the forward reamer 160, both the drill pipe 136 and the forward reamer 160 are retrieved to the entry pit 30. Then, the forward reamer 160 at the end of the drill pipe 136 is Figure 5 The coring head 210 and soil extractor 270 assembly is shown replaced.

[0037] Figure 5 An exploded view of the components of the coring head 210 and the soil extractor 270 is shown. The coring head 210 is configured similarly to the sleeve 212, and the positive annular end of the sleeve 212 is formed with an abrasive 180d. Similar to the above, the abrasive 180d can be made of tungsten carbide, industrial diamond, or similar hard abrasives. In one embodiment, the abrasive 180d is formed into an annular arrangement; in another embodiment, as Figure 6 As shown, the abrasive 180d is arranged in four parts to form four cutting blades. The abrasive 180d or the cutting blades can be formed by coating, depositing or impregnating in a processing chamber; alternatively, the abrasive part or the cutting blade can be provided as a solid piece and welded or brazed to the forward end of the coring head 210. Preferably, the second end or the opposite end of the coring head 210 is formed with a female threaded joint BSC.

[0038] Connectable to the BSC of the coring head 210 is a subassembly of a soil extractor 270. Figure 5 As shown, according to one embodiment, the soil extractor 270 is composed of a split mold 271, a sleeve joint 274, a stabilizing device 276 and a bent joint 278. Figure 7 The assembled mold 271 is shown, and Figure 8-9The split die 272 is shown divided into two halves. The split die 271 is basically composed of a split annular sleeve 271, each end of which has a male threaded connector PSC of associated size to cooperate with the BSC formed on the coring head 210. Figure 8 and Fig. 9 As shown, the split annular sleeve 271 is split along the longitudinal axis to form two split halves 271a, 271b. Figure 9-11 As shown, these splicing halves 271a, 271b are aligned and held together by three sets of pin 272-hole 273 mechanisms. In one embodiment, pin 272 can be threadedly fixed to the splicing edge on the splicing half 271b of the lower part, and the matching hole 273 is located on the splicing half 271a of the upper part. However, due to the symmetry of the splicing halves 271a, 271b, the pin 272 and the hole 273 are located on opposite sides, so the upper half and the lower half can be described reversibly. In another embodiment, the pin 272 can be tightly fitted into the splicing edge instead of being threaded. Preferably, the cooperation between the pin 272 and the matching hole 273 is a loose cooperation, so that the splicing halves 271a, 271b can be relatively easy or quickly assembled or disassembled at the operation site.

[0039] from Figure 5 It can be seen that both ends of the split mold 271 are formed with male threaded joints PSC; the advantage is that the inner hole of the split mold 271 is kept cylindrical and smooth. Figure 5 As shown, the stabilizer 276 is configured as a substantially cylindrical housing having two extended and spaced apart strips of abrasives 180e, 180f on its outer cylindrical surface. In one embodiment, the strips of abrasives 180e, 180f are covered in a cylindrical shape of diameter D1; in one embodiment, D1 is substantially the extended diameter D (located at the coring head 210). D1 may be several percentage points greater than the diameter D, for example, the extended diameter D1 is less than 10% greater than the diameter D. When D1>D, the stabilizer 276 is used to further expand the borehole path 150 during soil coring, so that the stabilizer 276 forms a close contact in the borehole path 150; thus, during soil coring, the stabilizer 276 dynamically stabilizes or centers the coring head 210. In one embodiment, the front tip of the stabilizer 276 is formed with a male threaded connector PSC, and the opposite end is formed with a female threaded connector BSC. With this configuration, a sleeve joint 274 is provided to connect the PSC end of the split mold 271 with the PSC end of the stabilization device 276.

[0040] like Figure 5 As shown, in one embodiment, the rear end of the stabilizing device 276 can be threadedly connected to the proximal end of the drill pipe 136 (the drill pipe is at Figure 5In an alternative embodiment, the rear end of the stabilizing device 276 is threaded directly to the proximal end of the associated drill pipe 136.

[0041] Two field tests were conducted to demonstrate the working principles of the above-described apparatus 100 and directional pilot drilling, forward reaming and soil coring / sampling process 200. The soil at Site #1 (Kranji) was a soft marine clay. As shown in the penetration curves in FIG. 12 , the pilot drill path (now labeled 140a) and the borehole path (now labeled 150a) were substantially 30 m in length and substantially 12 m in depth. Due to the soft soil conditions, the borehole path traced a slightly deviated curve 150b as the forward reamer 160 was retrieved or withdrawn; this deviated curve 150b is expected in soft soils, and this result demonstrates that the depth curve method used in the above-described invention is quite accurate.

[0042] Fig.13 The above-described split mould 271 is shown being used to obtain a soil sample 201 at the end of the borehole path 150a at Site #1 (Kranji). Fig.13 It was demonstrated that the above-mentioned directional guide drilling process, forward hole expansion process and soil coring process can be successfully carried out in basically soft marine clay.

[0043] Fig.14 The above-mentioned split mold 271 is shown being used to obtain a soil sample 201 at the end of the drilling path 150c located at Site #2 (Kent Ridge). The soil at Site #2 (Kent Ridge) is relatively hard. Fig.14 As shown, the length of the drilling path 150c is substantially 30m and the depth is approximately 10m. At the entrance pit 30, the drilling path is launched (drilled) at an angle of incidence of approximately 8 to 13 degrees. In addition, the drilling path curve 140b is plotted to a depth of approximately 14m with the directional blades at the drill bit set to a pitch angle of approximately 3%. Another drilling path curve 140c is also plotted, but the directional blades are set to a pitch angle of substantially 8%; when the directional blades are set to a higher pitch angle, the plotted drilling path 140c has a substantially curved curve. Fig.14 , the topographic curve of the ground 10 and the borehole path curves 140b, 140c drawn at site #2 are shown to verify that the borehole path curve method used is reasonably accurate and reliable.

[0044] Fig.15 The split mold 271a, 271b is shown split in half and a soil sample 201 is obtained from Site #2. Fig.13 and 15The combined mold 271 is shown to be successfully used to obtain undisturbed soil samples in soft foundations and hard bottoms; this also demonstrates the working principle of the forward expansion and soil coring / sampling process 200, and the ability of the coring head 210 and soil extractor 270 of the present invention to obtain soil coring and soil sampling without interference.

[0045] Fig.16 A rope soil coring extractor system 300 according to another embodiment of the present invention is shown. Fig.17 and 18 The upper and lower parts of the rope soil coring extractor system 300 are shown respectively. As in the above embodiment, a drilling curve for drilling into the ground is planned, and a pilot drill path 140 is formed according to the drilling curve; the borehole path 140 is then expanded with a forward reamer 160 to form a borehole path 150; in this embodiment, a series of outer tubes 336 extended by BSC and PSC threaded connections are provided to arrange the borehole path 150, and the rope soil coring extractor 300 is sent down to one end of the outer tube 336 to obtain a soil sample 301. Fig.16 As shown, the soil coring extractor system 300 is comprised of an outer tube 336, an overshot 303, a soil extractor 370, and a coring head 310. The method of using the soil coring extractor system 300 facilitates obtaining multiple soil samples 301 without retrieving the outer tube 336.

[0046] like Fig.16 As shown, the soil extractor 370 and the coring head 310 are preferably fed downwardly into the outer tube 336 by gravity or pneumatic means. The upper end of the soil extractor 370 is provided with an overshot coupling 304. At a position rearward of the overshot coupling 304, the two parts of the outer tube 336 are joined by a transfer tube 305; the transfer tube 305 has internal steps 305a that cooperate with spring loaded latches 306 extending from the head assembly 375 of the soil extractor 370. When the latches 306 are connected with the steps 305a of the transfer tube 305, the soil extractor 370 is rotationally fixed relative to the outer tube 336. To retrieve the soil extractor 370, the overshot 303 is sent downwardly into the outer tube 336 by the rope 302 to connect with the overshot coupling 304; during the connection process, the latches 306 are released, and the soil extractor 370 is retrieved from the ground by withdrawing the rope 302.

[0047] like Fig.17As shown, the soil extractor 370 has a set of bearings 308 at the rear of the head assembly 375. The lower portion of the soil extractor 370 becomes non-rotatable relative to the outer tube 336 through the bearings 308; in other words, during the soil coring process, the coring tube 371 located at the lower portion of the soil extractor 370 remains non-rotatable because the outer tube 336 and the coring head 310 are rotating; during the soil coring process, the soil sample 301 is received in the coring tube 371. The coring head 310 has an abrasive ring (180g) Figure 16-18 ), which can be formed by coating, deposition, impregnation, welding or brazing; preferably, the abrasive 180g is as Figure 6 The abrasive 180g is similarly arranged as shown to form a soil coring or cutting edge; preferably, the abrasive 180g is covered to substantially the same diameter as the drilling path 150.

[0048] like Fig.18 As shown, near the coring head 310, the outer tube 336 has two belts of stabilizers 337; similar to the above description, the belts of the stabilizers 337 are covered with abrasive 180 or hard surface material 180c; when the outer tube 336 rotates during soil coring in the drilling path 150, the tightening contact provided by the belts of the stabilizers 337 helps to stabilize the soil coring process at the coring head 310.

[0049] A core gripper assembly 390 is provided at the lower end of the core tube 371, which is used to disconnect the soil sample 301 from the ground before retrieving the soil extractor 370. The core gripper assembly 390 consists of a grip case 391, a split ring 392, and a stop ring 393. The grip case 391 has a countersunk surface and cooperates with a matching conical surface on the split ring 392; the stop ring 393 defines the travel distance of the split ring 392. Preferably, the conical surfaces on the grip case 391 and the split ring 392 are hardened. After the soil coring process is completed and the soil extractor 370 is about to be pulled up from the inside of the outer tube 336, the split ring 392 squeezes the soil sample 301 and disconnects the soil sample 301 from its connection with the ground; in this way, the soil sample 301 remains in the core tube 371 in an undisturbed state after the soil extractor 370 is retrieved from the ground.

[0050] Preferably, the soil extractor 370 together with the coring tube 371 can slide freely in the outer tube 336; in order to facilitate the sliding of the coring tube 371 in the outer tube 336, a belt of a stabilizing device 376 is provided on the coring tube 372.

[0051] Although specific embodiments have been described and illustrated, it should be understood that many changes, modifications, variations and combinations of variations disclosed in the text description and the drawings may be made to the present invention without departing from the scope of the present invention; for example, the core tube 371 may be provided with an internal longitudinal split sleeve to accommodate the soil sample 301; similarly, the split mold 271 may be configured as an integral mold 271c (not shown in the drawings), and an internal longitudinal split sleeve is provided inside the integral mold 271c to accommodate the soil sample 201; in this way, the longitudinal split sleeve located inside the core tube 371 or the integral mold 271c will help to easily remove the soil samples 201, 301 in an undisturbed state.

Claims

1. A device for directional soil drilling, soil coring and soil sampling, wherein: The equipment for directional soil drilling, soil coring and soil sampling includes: a steerable drill bit that can be connected to the end of a drill pipe, the steerable drill bit and the drill pipe being rotatable by a pipe drill to form a drill guide path according to a predetermined curve; and A forward reamer, which can be connected to the end of the drill pipe at the distal end and can be rotated to expand the guide drill path to form a drilling path of a predetermined aperture; The drill pipe is made of an aluminum pipe with a predetermined length and outer diameter, and the drill pipe can be extended into a series of connected drill pipes, with a male threaded joint (PSC) formed at one end of each drill pipe and a matching female threaded joint (BSC) formed at the other opposite end of each drill pipe.

2. The device according to claim 1, wherein The forward reamer includes three regions: a stem region, a conical region, and a guide region. The guide region is located in a forward position and is formed with a diameter that substantially matches a diameter of the guide path.

3. The device according to claim 2, wherein: The guide area is configured in a long cylindrical shape, and abrasive is deposited at a front tip of the guide area.

4. The device according to claim 2 or 3, wherein: The guide area comprises two parts joined by a predetermined sized male threaded connection (PSC) and a matching female threaded connection (BSC), the PSC and BSC allowing the front tip to be removably replaced when the abrasive wears.

5. The device according to any one of claims 2 to 4, wherein: The conical region includes: a front conical region, a middle cylindrical region and a rear conical region.

6. The device according to claim 5, wherein: The cone angle subtended by the front conical region is smaller than the cone angle subtended by the rear conical region.

7. The device according to claim 5 or 6, wherein: A plurality of spiral belts of abrasive are formed on the conical surface of the front conical area.

8. The device according to claim 7, wherein: The forward reamer also includes an inner longitudinal bore leading to outlets formed on the front conical region and the rear conical region, the outlet on the front conical region being located between the spiral bands of the abrasive material.

9. The apparatus according to any one of claims 5 to 8, wherein: The cylindrical surface of the central cylindrical region is formed from a cylindrical band of abrasive or hard facing material.

10. The device according to claim 1, wherein: The device also includes: A coring head engages with a subassembly of a soil extractor that is threadably connectable to a drill pipe.

11. The device according to claim 10, wherein: The soil extractor includes a split mold for receiving a soil sample, the split mold being threadably connected to the coring head.

12. The device according to claim 10, wherein: The soil extractor includes: an integral mold; and a longitudinal sleeve disposed within the integral mold to accommodate a soil sample.

13. The device according to claim 11 or 12, wherein: The soil extractor further includes: a sleeve joint; and a stabilizing device capable of being threadably connected to the sleeve joint.

14. The device according to claim 13, wherein: Both ends of the sleeve joint are formed with female threaded joints (BSC).

15. The apparatus according to claim 13 or 14, wherein: The stabilization device is configured essentially as a cylindrical housing having two spaced-apart cylindrical belts of abrasive material having a predetermined extension diameter D1.

16. The apparatus according to claim 1, wherein: The device also includes: a series of connected outer tubes for arranging the drilling path and having the coring head attached to the ends of the outer tubes; and A rope soil extractor is capable of being received within the outer tubes in series, and a core tube is configured at the lower end of the rope soil extractor for receiving a soil sample.

17. The apparatus according to claim 16, wherein: The core tube further comprises a longitudinally spliced ​​sleeve, and the longitudinally spliced ​​sleeve is used for receiving the soil sample.

18. The apparatus according to any one of claims 10 to 17, wherein: The coring head is basically configured as a sleeve, and a ring with a cutting edge consisting of abrasive is formed at the annular edge of the sleeve.

19. The apparatus according to claim 18, wherein: The abrasive rings are arranged in multiple sections.

20. The apparatus according to claim 18 or 19, wherein: The abrasive is formed by coating, depositing, impregnating, welding or brazing the abrasive onto the coring head.

21. A method for soil coring and soil sampling, wherein: The method for soil coring and soil sampling comprises: Identify underground locations for soil sampling; plotting a bore curve from the entry pit to the subsurface location for soil sampling; conducting guided drilling along the drilling curve using a steerable drill bit attached to the end of a drill pipe, the drill pipe being extended during drilling; After pilot drilling, the drill pipe and the drill bit are retrieved to the entry pit, the drill bit is replaced with a forward reamer, and the drill pipe is driven in to expand the pilot drilling path to form a drilling path; retrieving the drill pipe and the forward reamer to the entry pit, replacing the forward reamer with a coring head and a soil extractor, and driving the coring head and the soil extractor into the borehole path with the drill pipe to obtain a soil sample; and The drill pipe, coring head, soil extractor, and soil sample are retrieved from the underground location.

22. A method for soil coring and soil sampling, wherein: The method for soil coring and soil sampling comprises: Identify underground locations for soil sampling; plotting a bore curve from the entry pit to the subsurface location for soil sampling; conducting guided drilling along the drilling curve using a steerable drill bit attached to the end of a drill pipe, the drill pipe being extended during drilling; After pilot drilling, the drill pipe and the drill bit are retrieved to the entry pit, the drill bit is replaced with a forward reamer, and the drill pipe is driven in to expand the pilot drilling path to form a drilling path; driving an outer tube having a coring head at an end thereof and extending the outer tube so that the coring head reaches the end of the drilling path; and A rope soil extractor is lowered into the inner bore of the series-connected outer tube, the outer tube is rotated to perform soil coring, and after the soil sample is received in a coring tube connected to the soil extractor, the rope soil extractor and the soil sample are retrieved from the underground location.

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