Drilling system for recovering near-intact cores from loose to hard ground

Abstract

The device operates with a conventional rotary drive with a piling hammer. The torque and impact of the drill head are transmitted to the drill start pipe (8) at the drill bit. Inside the rotating start pipe (8) is a non-rotating sleeve (17). The non-rotating sleeve (17) is attached at the bottom to the inside of the drill bit, which rotates underneath. As a unique feature, the sleeve (17) is connected by compression and tension via a sleeve adapter (21) to an axial series that is rotatable relative to each other and is also connected to a pressure, flushing, and recovery pipe (PFR) (19) connected to the series together with the rotating drill head. The PFR (19) rotates together with the drill head and drill pipe, and the sleeve adapter (21) is connected to the non-rotating sleeve (17). With respect to the PFR, firstly, the sleeve (17) is pressurized from above, secondly, flushing is effected so that flushing water for the bore is directed into the PFR (19) and forced outward from the pressing sleeve (17), and thirdly, the sleeve (17) can be retrieved to obtain a drilled sample with little damage.

Description

[Technical Field]

[0001] The drilling system specifically relates to a method and device for capturing drill core from hard as well as soft ground, whereby nearly intact drill core samples can be captured and deposited. [Background technology]

[0002] This means that cylindrical drill cores, also known as drill core catchers or drill sample catchers, are retrieved from the ground in hollow cylindrical sleeves and transported to the surface. Such cores are, for example, about one meter long and 10 to 20 cm in diameter. However, their length can be significantly larger or smaller depending on the requirements and dimensions of the drilling machine. At the surface, the drill cores are removed from the hollow cylindrical sleeves and then laid horizontally and freely accessible on, for example, the inner shell of a semi-cylindrical cylinder or on a flat base. When such soil samples are removed from the sleeves, they are not 100% intact, insofar as they partially crumble due to the hardness of the material. However, the sleeves can also be fitted with a liner, made of, for example, rigid polyvinyl chloride or another suitable material, which fits snugly against the inner wall of the sleeve and is then pushed through the soil material along with the sleeve during the drilling operation. In this case, after the sleeve is retrieved, the liner is removed from the sleeve leaving the drill core unchanged as it was in the ground, and the liner can later be released, for example by cutting its diameter into sections, so that the sample remains completely intact. One advantage of using a liner is that any volatile contaminants present in the drill core are trapped and remain stored in the drill core after it is retrieved from the sleeve. However, the use of liners is more complicated and also more expensive than drilling without such a liner.

[0003] The soil samples collected in this way provide information about the soil's quality, specifically about any contaminants that have seeped into the soil over time. Therefore, a reliable damage register can be created, and appropriate measures can be initiated to improve such soils. This is particularly relevant to agronomy, where knowledge about the soil's quality, its mineral composition, and its nutrient richness can be gained, or possible soil deficiencies can be learned. Knowledge can then be gained about which crops the soil is suitable for and how fertilizers should be applied, ultimately facilitating ecological and high-yield management of agricultural land. Such core drilling is also suitable for obtaining soil samples from old landfills, suspected contaminated soils, and loose rock layers, as well as fine sand, peat, and marine chalk. The drilling method also works in soil layers under groundwater.

[0004] Obtaining soil samples for geotechnical evaluation from solid ground is well known and frequently used. Currently, there is an internationally recognized standard penetration test (SPT) defined in the American Society for Testing and Materials (ASTM) standard D1586. The test uses a thick-walled sample tube with an outer diameter of 50.8 mm, an inner diameter of 35 mm, and a length of approximately 650 mm. This is driven into the ground at the bottom of the borehole by impact with a slide hammer weighing 63.5 kg, which drops the tube over a distance of 760 mm. The sample pipe is driven 150 mm into the ground, and the number of blows required to penetrate the pipe 150 mm into the ground to a depth of 450 mm is recorded. The sum of the number of blows required for the second and third 6-inch penetrations is called the "standard penetration resistance" or "N-value," expressed in blows per foot (bpf). This value is essential for many types of geological calculations, such as bearing strength and subsidence estimation. If 50 blows are insufficient to advance the penetration at 150mm intervals, the penetration after 50 blows is recorded. The blow count produces an index of soil density, which is used in many empirical geotechnical formulas.

[0005] While drilling hard ground is well-established in the state of the art, drilling loose ground and especially retrieving drill cores from loose ground is particularly laborious. This is because, in addition to the rotary drill bit, a piling is required for drilling, i.e., strong impacts are required on the drill head, which then needs to transfer these force impacts to the entire drill pipe, i.e., the drill pipe, the core barrel, and the drill bit attached to the drill pipe. All parts are therefore subjected to enormous mechanical and thermal stresses, so that their service life is often less than desired. For this reason, no practically satisfactory drilling system yet exists that delivers reasonably acceptable core quality and, above all, also provides an acceptable service life for the drilling system used.

[0006] Therefore, extraction of cylindrical soil samples from loose ground has been carried out in the past with drilling rigs of a fairly special design. The drilling rig encloses a drill pipe having a starter tube with a drill bit at its lower end, whereby drilling into the ground is carried out by rotating the drill pipe, and thus also the starter tube and the drill bit, and simultaneously by hammering and thus ramming. Inside the starter tube, a sleeve is inserted with little clearance as a drill core catcher. This sleeve is located at the bottom of the drill bit on a protrusion that projects radially inward from the drill bit.

[0007] Such a drilling method is described in EP 2050923 A1. The drilling method is described as requiring that the drill core catcher or sleeve be held inside the initial pipe to prevent its rotation. For this purpose, a special fixing rod is proposed that is rotatably fixed, i.e., does not rotate, and extends all the way from the top to the bottom of the drill pipe. The fixing rod is intended to fasten the rotatably fixed sleeve. However, it has been shown that in practice, the fixing rod does not need to hold the sleeve on the drill rig so that it cannot rotate. The reason for this is that when the sleeve is lowered or sunk, it is somehow clamped by the drill core itself, which enters the sleeve through the drill core, to ensure that the sleeve does not rotate. In principle, the result is that the sleeve does not rotate during drilling, but rather is pushed down axially all the way through the drilled-out core and sunk all the way through this core, without rotating with the movement of the initial pipe that rotates around it. Thus, practical experience has shown that the problem sought to be solved in EP 2050923 A1 was unrealistic, i.e., no solution to the problem existed at all. A drill core growing in a submerged sleeve rotates very little, or at most only very slightly, simply because it is connected to the ground. As a result, a locking rod to hold the sleeve in place and prevent it from rotating is not needed. Locking rods can also have adverse effects, namely, when, under certain substrate conditions, the sleeve rotates by a small angle in the direction of the core bit's rotation, despite the rotation-resistant locking rod. While this does not affect the quality of the drill core, when such a locking rod is used, it cannot absorb the resulting twisting and will shear. This leads to unplanned and lengthy drilling shutdowns and time-consuming improvisation efforts to somehow recover the core.

[0008] However, usually, after the drilling section has reached its destination, the drilling section is stopped, the sleeve together with the drill core is pulled up from the starter pipe, the drill core is pushed out of the sleeve in a horizontal position, and the empty sleeve can be reinserted into the starter pipe. For deeper drilling, an extension of a portion of the drill pipe can carry the starter pipe together with the drill core to a deeper position. In this regard, a method is presented in EP 2050923 A1.

[0009] In the prior art, so-called rope core drilling methods are known, which allow the drill core to be easily retrieved from hard rock or hard ground. These methods work using devices with clinker closures, which have complex structures that are unsuitable for drilling loose ground. This is because, as a result of the necessary ramming impacts, these devices for retrieving the drill core will likely fail within a fairly short time. Furthermore, it is not possible to use ropes to push down the casing or core catcher over the exposed drill core.

[0010] The difficulty of obtaining such cores from loose soil is manifold and almost exceptionally underestimated. Drilling rigs can generate torques of up to 28,000 Nm, and the impact of the pile driving can produce enormous force impulses, i.e., for example, 2400 min -1 The resulting impacts have fairly high force peaks with individual impact energies of up to 500 Nm, which are used at frequencies of 1000 m / s. This places extreme demands on the structure and its stability, which are difficult to determine purely by calculation. Many parts used in the tests proved to be worn out and unusable after a short period of use. Reference is made here to, for example, sonic hammer drills, or more generally to all commercially available drill drives and hammer drills, and these drills apply throughout.

[0011] Also, improper drilling techniques can result in contaminants from certain geological formation depths being carried down from the drill bit or core barrel during the drilling process, making the recovered drill core samples largely unrepresentative of their original state.

[0012] So far, no excavators are available that can be considered suitable for collecting soil samples in almost their original state, not only from solid rock masses but also from loose rock masses, in particular in the form of cores. Known devices do not function reliably over long periods of use, making it impossible to efficiently and simply obtain and retrieve cores, especially from loose ground, and thus to retrieve as many cores per unit of time as possible without damage. [Prior art documents] [Patent documents]

[0013] [Patent Document 1] European Patent Application Publication No. 2050923 [Non-patent literature]

[0014] [Non-Patent Document 1] American Society for Testing and Materials (ASTM) Standard D1586 Summary of the Invention [Problem to be solved by the invention]

[0015] Against this background, the present invention itself was designed to provide a drilling system, i.e., a method and a device for obtaining nearly original soil samples, specifically from loose ground but equally from hard subsoil, which is clearly superior to conventional methods in several respects: the actual drilling should be faster and possible drilling interruptions should be short and to a minimum; the device is expected to have a much longer service life than conventional drill pipes and their components; the borehole should provide a nearly original soil sample, and, depending on its nature, it should be possible to ensure that in the event of collapse due to the hardness of the material, the information value of the sample examination is not or only slightly impaired. [Means for solving the problem]

[0016] This problem is solved by a method according to the features of patent claim 1 and with a device for carrying out the method according to the features of patent claim 6.

[0017] In the following description, this drilling system, i.e., apparatus, and a method of operating with the apparatus are presented, and individual features and aspects of the method and apparatus are explained in an understandable manner. Specific features and operation of the apparatus, and components of the apparatus, are described generically. [Brief explanation of the drawings]

[0018] [Figure 1] A hammer drill with a drive and a hammer for rotating the drill head with a hammer. [Figure 2] A hammer drill in a horizontal position, seen from below. [Figure 3] A hammer drill with the drill head in an upright position. [Figure 4] A drill head shown separately, with external threads for screwing onto the drill pipe. [Figure 5]A drill head with a central axial hole for flushing and radial holes for ventilation is shown in Figure 4 in longitudinal section. [Figure 6] An assembled drilling system consisting of a drilling head, drill pipe, initial pipe, and drill bit attached to the drilling system. [Figure 7] Figure 6. Complex excavation system viewed from below at an angle. [Figure 8] Drill pipe as an extension element seen obliquely from below. [Figure 9] Figure 8 Drill pipe as an extension element seen obliquely from above. [Figure 10] A close-up of the drill bit seen from below. [Figure 11] Shown assembled from top to bottom are the pressure, flushing, and recovery pipe adapters (PFR adapters), followed by the pressure, flushing, and recovery pipe PFR, and at the bottom of the pressure, flushing, and recovery pipe PFR is a sleeve or core catcher. [Figure 12] PFR adapter installed on top of pressure, flushing, and recovery pipe PFR. [Figure 13] Pressure, flushing and recovery pipe PFR as extension element, seen from below at an angle. [Figure 14] A sleeve adapter for impact pressure resistant connections of sleeves or drill core catchers to pressure, flushing and recovery pipes, viewed diagonally from top to bottom. [Figure 15] Sleeve adapter of Figure 14 for impact pressure resistant connection of sleeve or core catcher to pressure, flushing, and recovery pipes, viewed diagonally from top to bottom. [Figure 16] 16 is an exploded view of the sleeve adapter of FIGS. 14 and 15, with the individual parts aligned; FIG. [Figure 17] A sleeve or core catcher seen diagonally from below. [Figure 18] A sleeve or core catcher seen tilted from above. [Figure 19] Rolling spring retainer in sleeve to hold core. [Figure 20] The drill head above the underlying pressure, flushing, and recovery pipes with the initial pipe underneath, with the sleeve inserted before being removed from the initial pipe. [Figure 21] Pressure, flushing, and recovery pipe at point of pulling upward to remove sleeve or core catcher from initial pipe. [Figure 22] Pressure, flushing, and recovery tubes after the sleeve or core catcher is withdrawn upward from the initial tube. [Figure 23] Sleeve adapter pulled out of sleeve at bottom of pressure, flushing, and recovery tube. [Figure 24] The bottom of the sleeve adapter is shown enlarged to reveal the bore for the fixing bolt and the fixing bolt next to the bore. [Figure 25] Pressure, flushing, and recovery tubes with sleeve adapters in connection with empty or empty sleeves. [Figure 26] Pressure, flushing, and recovery tubes with sleeve adapter and empty sleeve before insertion into the initial tube. [Figure 27] Pressure, flushing, and recovery pipes with sleeve adapters and empty sleeves inserted into the initial pipe when installing drill pipe onto the initial pipe. [Figure 28] Pressure against the initial pipe, flushing, and downward movement of the drill pipe across the recovery pipe. [Figure 29] The drill pipe is being screwed into the initial pipe. [Figure 30] The prepared drill pipe threaded against the initial pipe. [Figure 31] PFR adapters installed on top of the pressure, flushing, and recovery pipes.PFR adapters installed on top of the pressure, flushing, and recovery pipes. [Figure 32]PFR adapters for pressure, flushing and recovery pipe PFRs mounted ready to use. [Figure 33] The drill head sits atop the pressure, flushing, and recovery pipes and the upper end of the upper drill pipe. [Figure 34] Close-up of the lower threaded section of the drill head and PFR adapter with the pressure, flushing, and recovery pipes connected to the bottom inside the drill pipe. [Figure 35] A drill head with a drive flange underneath that extends over the upper end of the pressure, flushing, and recovery pipe for threading against the drill pipe. [Figure 36] A drill head with a drive flange threaded against the drill pipe. DETAILED DESCRIPTION OF THE INVENTION

[0019] First, Figure 1 shows a hammer drill with a drive and hammer for rotating the drill head with a hammer, such as those commercially available. At the bottom, an output shaft 1 with a screw 3 protrudes, which is rotated by a laterally arranged hydraulic drive 2. Inside, the hammer drill houses a hammer mechanism, which is ram-broken from above on the output shaft 1. The rotation speed of the drive varies from about 50 to 1000 rpm. As the speed decreases, the torque on the output shaft 1 increases, reaching about 15 kNm at 50 rpm. The hammer impact force is generated with a water pressure of up to 200 bar and can reach a maximum of 2400 min. -1, delivering impact energies of up to 500 Nm. In Figure 2, the hammer drill is shown in a view from below, with the output shaft 1 projecting downwards, and in Figure 3, in the upright position in use when the hammer drill is in use, the drill head 5 is connected below to the output shaft 1, for which purpose a screw 3 on the output shaft 1 is screwed into the drill head. Figure 4 shows the drill head enlarged and separated, with an external thread for screwing into the drill pipe, and in Figure 5, the drill head is further shown in longitudinal section. The central axial bore 6 for flushing, the axial bore 37 with its inner wall from below, and the radial bores 7 for ventilation can be seen.

[0020] The drilling system according to the invention will now be presented and explained starting from Figure 6. Here, the drilling system 4 is first seen as a whole from the outside. The drilling system 4 is, in principle, quite simple, consisting of only eight parts, namely, from top to bottom, as seen from the outside: 1. Drill head 5 2. One or more drill pipe sections threaded together to form drill pipe 9 3.Initial tube 8 4. Drill Bit 10 The parts that are inside the drill pipe 9 or drill pipe section and the initial pipe 8, and therefore not visible in FIG. 6, are the following parts, which are shown from top to bottom in FIG. 5. Pressure, Flushing, and Recovery Pipe Adapter (PFR Adapter) 18 6. One or more pressure, flushing, and recovery pipes (PFR) threaded together 7. Sleeve Adapter 21 8. Sleeve 17

[0021] First, Figure 6 shows the assembled drilling system 4 with the driving drill head 5 at the top. The drill head 5 screws into the female threads of the adjacent drill pipe 9, which can then drive and rotate the drill pipe 9 in a clockwise direction when viewed from above. Here, the lower male thread of the drill pipe 9 screws into the matching female threads on the upper part of the initial pipe 8. These threads are relatively coarse threads milled out of the pipe material. After each screwing together using the rotating drill head 5, the threads are preferably re-greased. If there is more than one drill pipe section, the drill pipe 9 can be advanced and extended deeper into the ground. The drill pipe sections are advantageously approximately one meter long. They can then be conveniently stacked on the drilling rig for insertion, supported by one person. The initial pipe 8 supports the drill bit 10 at its lower end. Figure 7 shows this composite drilling system from an oblique view below, while Figure 8 shows a single drill pipe 9 from an oblique view below. At the lower end, a relatively coarse external thread 11 is formed in the drill pipe 9 so that it can be threaded into a matching internal thread 12 of an adjacent drill pipe 9, such as that shown in FIG. 9, or, with the above formation, the coarse external thread 11 can be threaded into the lowest pipe, i.e., the initial pipe 8. As seen from above, the hammer drill drive rotates clockwise when drilling, i.e., in terms of tightening these connecting threads 11, 12. Of course, drilling in a counterclockwise direction is equally possible, but then the threads used would also need to go around the other path.

[0022] Finally, FIG. 10 shows an enlarged view of the drill bit 10, viewed obliquely from below. The drilling segments 13, offset by carbide pins, are brazed to the bottom of the drill bit, and a lateral outer spacing element 15 with an inclined surface 14 provides upward spacing. The volume of material axially located below the drill bit segments 13 of the drill bit 10—i.e., the volume of material located exactly below the rotating ring formed by the drill bit 10—is partially deposited into the drill core, partially deposited into the surrounding ground, and partially transported upward when excessive weight is applied to the outside of the drill bit 10, initial pipe 8, and drill pipe 9. In the lower area of ​​the drill bit 10, a shoulder 16 is formed on the inside of a radially inward-protruding protrusion, on which a sleeve, drilling sample sleeve, or drill core catcher rests, although this is not shown here. This sleeve is flush with the inside of this protrusion. Thus, as the drill bit 10 advances, the submerged sleeve or drill core catcher overlaps the exposed drill core, tightly enclosing it. Other commercially available drill bits, such as diamond or otherwise pointed bits, can be used.

[0023] Starting at the bottom, Figure 11 shows the sleeve 17 or drill core catcher. Continuing to the top, one can see the sleeve adapter 21, then the pressure, flushing, and recovery pipe 19, topped by the pressure, flushing, and recovery pipe adapter 18. The pipe adapter 18 is where the impact of the pile driver acts. In the example shown, this pressure, flushing, and recovery pipe 19 rotates uniformly with the initial pipe 8 and any inserted drill pipe sections for drill pipe 9 (Figure 6).

[0024] A rather special and crucially important element is the sleeve adapter 21 between the pressure, flushing, and recovery pipe 19 and the sleeve 17 or drill core catcher, as shown here. While the pressure, flushing, and recovery pipe 19 rotates and impacts, the submerged sleeve 17 does not rotate but surrounds the drill core that grows inside the submerged sleeve 17 during drilling. Only powerful, high-frequency ramming impacts act from the pressure, flushing, and recovery pipe 19 on the sleeve 17, exerting enormous peak forces on this sleeve adapter 21. Therefore, this adapter must be interposed between the rotating pressure, flushing, and recovery pipe 19 and the non-rotating sleeve 17, and must simultaneously be able, on the one hand, to absorb and permanently withstand the enormous impacts at high impact cadences, and, on the other hand, to translate the rotation of the pressure, flushing, and recovery pipe 19 relative to the non-rotating support of the sleeve 17. Since this cannot be done without sliding friction, it is clear that a large amount of frictional heat is also generated. The sleeve adapter 21 should be able to absorb this thermally, and at the same time, the sleeve adapter 21 needs to be properly cooled to handle this continuously generated frictional heat and dissipate it to the outside.

[0025] 12 shows a close-up view of the pressure, flushing, and recovery pipe adapter 18, or PFR adapter, above the pressure, flushing, and recovery pipe 19. Through an axial bore with an inner wall 52, flushing water travels downward through the interior of the pressure, flushing, and recovery pipe 19 and is directed outwardly within the sleeve adapter 21 toward the outside of the initial pipe 8. A circumferential annular groove 54 can be seen in the pressure, flushing, and recovery pipe adapter 18 into which an O-ring is inserted to seal against the inner wall of the axial bore 37 of the drill head 5.

[0026] 13 shows, as required, a hollow pressure, flushing, and salvage pipe section (PFR) 53 as an extension pipe to the hollow pressure, flushing, and salvage pipe 19, with the PFR 53 simply threaded with a lower external thread into an upper internal thread associated with the pressure, flushing, and salvage pipe 19 connected below. The extension pipe 53 thus substantially matches the actual pressure, flushing, and salvage pipe 19, and in the example shown has an internal thread at the top for extension.

[0027] In the following, a very essential and specific element of this drilling system will be presented: the sleeve adapter 21, which ensures the connection from the PFR 19 to the sleeve 17. For this purpose, FIG. 14 shows, in a diagonal view from above, this sleeve adapter 21 for the impact pressure-resistant connection of the sleeve 17 or drill core catcher to the pressure, flushing, and recovery pipe PFR 19. At the top, a threaded stub 35 protrudes from the sleeve adapter 21 and terminates at the bottom of the sleeve adapter's base 22, which forms a plate or shoulder 44 at the top. On this threaded stub 35, located on the base 22, the pressure, flushing, and recovery pipe 19 is threaded into the lower internal thread and thus rotates uniformly with the drill pipe 9 and the rotating pressure, flushing, and recovery pipe 19. A sealing ring 36 continues downwards, preferably made of hard plastic rubber, and can rotate together with the base 22. The fixed lower part 24 of the adapter 21 is connected to the sleeve 17 in a pressure-locked but non-rotational manner, with the resulting pressure, flushing, and rotation of the salvage pipe 19 absorbed between the base 22 and the fixed receiving ring 23. Here, on the visible portion of the lower part 24, the sliding sleeve 25 can be seen, and its importance becomes clear. The sleeve 17 or core catcher is pressed from below over this lower part 24 with a precise fit until the upper edge of the sleeve 17 abuts the sliding sleeve 25 at the bottom. A compression ring 33 made of hardened steel is also attached to the bottom of the adapter receiving ring 23. At the bottom of the lower part 24 of the base 22, a rubber washer 27 can also be seen, which protrudes slightly radially beyond the lower part 24 to seal the sleeve adapter 21 against the inner wall of the sleeve 17.

[0028] In FIG. 15, the sleeve adapter 21 is shown in a diagonal view from below. Here, as before, from top to bottom, we can see first the threaded stub 35 for screwing onto the pressure, flushing, and recovery pipe 19 from above. Next, we can see the shoulder 44 of the base 22 of the sleeve adapter 21, followed immediately by the plastic hard rubber sealing ring 36 resting on the receiving ring 23. This is followed by the sliding sleeve 25, under which we can see the compression ring 33 made of hardened steel. The rubber washer 27, which protrudes slightly radially to contact the inner wall of the sleeve 17 and seal the sleeve adapter 21, is fastened to the lower part 24 by the steel washer 29 and, here, four axial screws 31. We can also see the diametric bore 43 for the fixing bolt, which then extends through this diametric bore in the lower part 24, as will be apparent from the next view, as well as the bore 38 for the locking bolt.

[0029] The detailed structure of the sleeve adapter 21 can be seen in FIG. 16, which shows the sleeve adapter 21 in an exploded view with the parts separated along the central axis. Starting from the top, first, we can see the base body 22 of the adapter 21, which is intended to rotate, followed by the seal ring 36, a hard plastic rubber ring that contacts and seals with the initial tube 8. This then rests on the receiving ring 23, shown below. This receiving ring 23 is fixed, i.e., does not rotate, during operation, and is integrated at the bottom into a tapered section, which has a radial bore 41 around its entire periphery into which a cylindrical pin 32 fits; the pin 32 is shown further down in the lower section 24, and its function will soon become apparent. Below the receiving ring 23, the circlip / seegler ring 26 is shown as a retaining ring that rests in an annular groove 45 in the base body 22 when assembled. Similarly, from below, the fixed lower part 24 of the sleeve adapter 21 is pressed over this tapered portion of the receiving ring 23, and then the cylindrical pins 32, which are depicted all around, are pressed from the outside into the radial bores 42 of the lower part 24, and likewise into the radial bores 41 of the receiving ring 23, and then the radial bores 41, 42 align, thereby rotatably fixing and connecting these two parts 23, 24 to each other. After the insertion of these cylindrical pins 32, the sliding sleeve 25 slides over this tapered lower part of the receiving ring 23, covering and thus securing the cylindrical pins 32.

[0030] The retaining ring 26 is then inserted into the annular groove 45 at the lower end of the base 22, thereby securing the retaining ring 26 to the base 22 with the axially secured locating ring 23. The lower portion 24 of the adapter 21 has a diametric bore 43 for receiving a securing pin (not shown). Two radial bores 38, perpendicular to the diametric bore 43 and lying on a common axis, are inserted into the radial bores 38 to secure the inserted securing bolts 34. Each of these two securing bolts 34 has a forwardly pressure-loaded ball 40 that engages a longitudinal groove in the inserted locating bolt and secures the recess 56, e.g., by engaging the recess 56 partially along the length of the groove. After insertion into the bores 38, the securing bolts 34 are secured by a circlip / segar ring 39. Flushing water flows outward, as will become apparent, from top to bottom through the hollow pressure, flushing, and recovery pipe 19, axially through the drill fixing bolts in the bore 43. This flushing water flows first through the sleeve adapter 21 and then radially out the lower part 24, i.e., through the fixing bolts in the axial bore, on both sides, at the end faces, and thus outward. The thrust ring 33 absorbs the axial force acting on the sliding sleeve 25 and distributes it evenly to the locating ring 23, made from aluminum bronze. A rubber washer 27 and a slightly smaller steel washer 29 are fastened to four washers 28 and, as shown, by four screws 31 and their associated spring washers 30, securing the washers 27, 29 to the lower part 24.

[0031] FIG. 17 shows the sleeve 17 or drill core catcher as seen from below at an angle. At its lower edge, the sleeve 17 is fitted with several spring steel elements 20 distributed around its periphery, which protrude upward and arcuately toward the central axis of the sleeve 17. When the sleeve 17, which receives a ramming impact from above, as well as the initial tube 8 and drill bit 10, is inverted from above over the entire exposed drill core as the drill bit 10 and initial tube 8 drill forward, these spring steel elements 20 are pressed against the inner wall of the sleeve 17 by the drill core. The sleeve 17 is then placed over the entire fixed drill core without rotating and moves purely axially; thus, the spring steel elements 20 are attached to the inside of the sleeve 17. However, when the sleeve 17 is pulled up together with the pressure, flushing, and recovery tube 19, these spring steel elements 20 act as barbs. If the drill core does not generate sufficient adhesion when the sleeve 17 is pulled up together with the pipe 19, these spring steel elements 20 will radially engage the drill core in the event of a slight slippage of the sleeve 17 on the drill core, bend towards the central axis of the sleeve 17 and form a catch basket for the drill core, so that the spring steel elements 20 are firmly held on the sleeve 17 and prevent it from slipping downwards, i.e. reliably preventing core loss of loose rock. In the upper edge region of the sleeve 17, a radial bore 46 can be seen for flushing water emerging from the sleeve adapter 21.

[0032] FIG. 18 shows the sleeve 17 or drill core catcher seen at an angle from above, revealing two diametrically aligned holes 46 made in the upper edge region of the sleeve 17. As the sleeve 17 slides over the lower part 24 of the sleeve adapter 21, these two bores 46 lie on top of the radial bores 43 in the lower part 24, so that flushing water flowing out from the end faces of the fixing pins inserted in the bores 43 eventually penetrates from the inside to the outside of the adapter 21 and through these aligned bores 46 in the upper region of the sleeve 17, far to the outside. This flushing water performs several functions. First, it cools the sleeve adapter 21, which is heated by the sliding friction between the rotating base 22, the plastic hard rubber sliding ring 36, the fixed receiving ring 23, and the lower part 24, and which is also heated by the ramming impact. Furthermore, the flushing water lubricates between the outside of the non-rotating sleeve 17 and the inside of the initial pipe 8 which rotates around the sleeve, and finally the flushing water carries debris radially outwards from under the drill bit 10 and then upwards on the outside of the initial pipe 8. This continuously flushes the borehole and also lubricates and cools the outside of the initial pipe 8. However, depending on the circumstances, it is also possible to dry the drill.

[0033] Figure 19 shows the insert in a relaxed, unwound state, with the spring steel element 20 forming, as it were, a comb. As can be seen in Figure 17, this comb is wound longitudinally and then inserted into the bottom of the sleeve 17, this comb resting on the inner shoulder 58.

[0034] Thus, the individual parts of the drilling system are disclosed and explained. Now, how does one work with this drilling system to drill loose ground and retrieve drill cores from the loose ground? For this purpose, the entire procedure is explained by a series of diagrams, as shown, for example, in Figures 20 to 36.

[0035] First, FIG. 20 shows the exposed initial pipe 8 with the sleeve 17 inside it at the bottom, and the hollow pressure, flushing, and recovery pipe 19 threaded onto the initial pipe 8 by the sleeve adapter 21. Above this is the drill head 5, which is set to rotate by the hydraulic drill drive of the hammer drill 2 via a flange 47. Between this drill head 5 and the lowest section, an initial pipe 8, a drill pipe section, can be inserted as needed as an extension pipe for the drill pipe 9, depending on the desired drilling depth. The drill head 5 is initially threaded directly onto the initial pipe 8. Drilling is then carried out until the initial pipe 8 is drilled almost to the bottom. The drill head 5 is then rotated counterclockwise to unscrew the initial pipe 8. When the initial pipe 8 is in the ground, and as shown here, when the initial pipe 8 is exposed, i.e., the drill head 5 and drive flange 47 have been removed, the pressure, flushing, and recovery pipe 19, along with the sleeve 17 hanging from the pipe 19 at its bottom, can be pulled axially upward from the initial pipe 8, just revealing the sleeve adapter 21, as shown in FIG. 21 . In FIG. 22 , the adapter 21 has been fully pulled out of the initial pipe 8 by the pressure, flushing, and recovery pipe 19, along with the sleeve 17 or drill core catcher hanging from the pipe 19. Here, the face of the locking bolt 48 holding the sleeve 17 tightly to the sleeve adapter 21 can be seen. In this situation, the sleeve 17 is pulled up from the initial pipe 8 by the pressure, flushing, and recovery pipe 19 until it finally reaches the surface.

[0036] As shown in FIG. 23, once at the surface, as already done in the illustrated view, the locking bolt 48 is slammed, pulled, or pushed out of the bore 43 in the lower portion 24 of the sleeve adapter 21. Here, only the empty diametric bore 43 in the lower portion 24 of the sleeve adapter 21 is visible. As can be seen in FIG. 16, the locking pin 34 is inserted into two bores 38 made at right angles to the bore 43, which have forward-facing balls 40 pressurized by compression springs. As is clear from FIG. 24, the locking bolt 48 is forced out of the diametric bore 43 in front of the retaining bolt 34 against the resistance of these pressure-loaded balls 40.

[0037] FIG. 24 shows the lower part 24 of the sleeve adapter 21 enlarged to reveal the inside of the diameter bore 43 for the fixing bolt 48, which is shown in isolation next to the sleeve adapter 21. However, to insert it into the lower part 24 of the sleeve adapter 21, it must first be rotated 45° about its longitudinal axis, as indicated by the arrow. From this locating pin 48, on two opposite sides, there are channel-shaped recessed longitudinal grooves 50, the bottom of which has a partially curved recess 56 that runs along the entire length of the locating pin 48. The spring-loaded balls 40 (FIG. 16) of the retaining bolt 34 fit into these recesses 56, and only when the fixing bolt 48 receives a sufficiently strong longitudinal blow can they overcome their clamping by pushing back the spring-loaded balls 40, which can then be pushed out or pulled out of the bore 43, while the longitudinal grooves 50 slide outward past the balls 40. As can be seen here, a central transverse bore 49 is formed in the locating pin 48 which communicates with an axial bore 55. These bores 49, 55 serve to guide flushing water which passes through the sleeve adapter 21 from above, through the axial bore 51, through the transverse bore 49 and into the fixing bolt 48, and then outward from the end face along the axial bore 55 into the fixing bolt 48. One of the holes 46, previously engaged and retained by the locating pin 48, through which the flushing water exits, can also be seen in the sleeve 17 in FIG.

[0038] Once the sleeve 17 or drill core catcher is in a horizontal position at the surface and the drill core lying in the sleeve 17 is carefully pushed out of the sleeve 17, either mechanically or hydraulically, using a piston in a jug-shaped drill core carrier, the drill core remains almost intact. The empty sleeve 17 can then be immediately reinserted to remove the next drill core, or the ready empty sleeve 17 can be immediately reinserted. In one variant, a liner can be inserted into the sleeve 17, which then lines up inside the sleeve 17 and the drill core grows. In this case, the retrieved drill core, together with the liner, is pushed out of the sleeve 17 and remains absolutely intact, like a sausage. Individual slices can be cut off to examine the structure of the drill core and its changing behavior along its entire length. In that process, when the sleeve 17 is transported to the surface together with the drill core, then after the sleeve 17 is separated from the sleeve adapter 21, the empty sleeve 17 can be immediately and without any delay connected to the sleeve adapter 21, which can then be immediately lowered back into the initial pipe 8 in the borehole, and thus drilling can continue without the need to interrupt drilling operations as a result of removing the drill core from the retrieved sleeve 17.

[0039] FIG. 25 shows how the sleeve adapter 21 is connected to the empty sleeve 17 by lowering it onto the sleeve 17, and when the hole 43 of the sleeve adapter 21 aligns with the hole 46 of the sleeve 17, the locating pin 48 can be inserted and the sleeve 17 can be lowered immediately into the initial pipe 8 together with the pressure, flushing, and recovery pipe 19. This lowering state is shown in FIG. 26. As soon as the sleeve 17 is fully inserted into the initial pipe 8, i.e., as soon as the sleeve 17 contacts the bottom of the drill bit 10, the next step proceeds as shown in FIG. 27. As shown in FIG. 28, the drill pipe 9 is slid over the entire pressure, flushing, and recovery pipe 19 as an extension pipe, lowered to the bottom of the initial pipe 8, and then screwed into the initial pipe 8 as shown in FIG. 29. After screwing, the situation shown in FIG. 30 is obtained. Finally, as shown in Figure 31, the pressure, flushing and recovery pipe adapter 18 of the pressure, flushing and recovery pipe 19 is first fitted or screwed on, and then, from the situation shown in Figure 32, the drill head 5 with the drive flange 47 is screwed on as shown in Figure 33. Details of this are shown in Figures 34 to 36.

[0040] As can be seen from this description and the drawings, the pressure, flushing, and recovery pipe 19 is appropriately named. First, the pipe 19 rotates uniformly with the drill pipe 9 or initial pipe 8 during drilling, and the sleeve adapter 21 is attached at its lower end to the fixed sleeve 17 or drill core catcher. Strong ramming impacts on the pressure, flushing, and recovery pipe 19 are reliably and directly transmitted by the sleeve adapter 21 to the sleeve 17 or drill core catcher. The drill core catcher is thus pressed down with the same pressure as the drill bit 10, ensuring continuous submersion of the sleeve 17 throughout the exposed drill core. Thus, the pressure, flushing, and recovery pipe 19 primarily fulfills a pressure function. During drilling, flushing water can be pumped downward through the pressure, flushing, and recovery pipe 19, which then flows outward through the sleeve adapter 21. That is, the flushing water first travels axially through the pressure, flushing, and recovery pipe 19, then travels axially through the sleeve adapter 21, and finally travels radially, i.e., axially through the diametrically inserted fixing bolts 48 on the two end faces, and then travels outward through the bore 46 of the sleeve 17. Therefore, the pressure, flushing, and recovery pipe 19 also has a second flushing function. When it is necessary to recover the filled sleeve 17 with the drill core trapped inside, the filled sleeve 17 with the drill core inside is recovered using the pressure, flushing, and recovery pipe 19 after the drill head 5 is loosened. Therefore, the pressure, flushing, and recovery pipe 19 also has a recovery function. The pressure, flushing, and recovery pipe 19 integrally combines these three important functions.

[0041] In the embodiment described so far, the pressure, flushing, and recovery pipes 19 rotate together with the drill head 5 and the drill pipe 9, and the sleeve adapter 21 is carried to the non-rotating or rotating sleeve 17 by having two axial continuations that are rotatable relative to each other. A sealing ring 36, preferably made of hard plastic rubber, is arranged between the axial continuations. In an alternative embodiment, a rotary disk body constructed similarly to the sleeve adapter, hereafter referred to as the drill head adapter, is screwed, with its upper part having a threaded stub, into a bore in the drill head 5 that has an internal thread for this purpose. The upper part of the rotary disk body or drill head adapter rotates together with the drill head 5, while the lower part, which is rotatable relative to the upper part, remains fixed. Here, the drill head adapter is connected to the upper end of the rotation, flushing, and recovery pipes 19 by a fixing bolt, just like the lower part of the sleeve adapter 21 already presented. However, the fixing bolt then does not require an axial bore, but only a lateral bore to allow the flushing water to proceed downward. At the bottom, the pressure, flushing, and recovery pipe 19 is then threaded only into the lower part of the sleeve adapter 21, for which purpose this lower part forms a threaded butt at the top, while the rotary, flushing, and recovery pipe 19 has an associated internal thread at the bottom. The lower part of the sleeve adapter 21 is connected to the sleeve 17 by means of the fixing bolt 48, as already presented, using the axial bore 55. As previously mentioned, flushing is brought from the drill head 5 through the pressure, flushing, and recovery pipe 19 and the lower part of the sleeve adapter 21, and then outward through the fixing bolt 48. In this alternative embodiment, the pressure, flushing, and recovery pipe 19 also performs the three functions mentioned above: first, to apply pressure to the sleeve 17; second, to flush the sleeve 17, thus cooling it; and third, to recover the sleeve 17 when it is filled, i.e., to pull it upward until it is exposed to sunlight.And in this embodiment, despite the fact that the pressure, flushing and recovery pipe 19 remains non-rotating, if the sleeve 17 rotates by a small angle in the process of being submerged over the entire drill core, the sleeve 17 can rotate together with the drill core and the drill head adapter is carried in this case to the rotary drill head 5 as a rotating disc body at the top with two parts that follow each other axially and are rotatable relative to each other.

[0042] Using the method according to the invention for core drilling from loose to hard ground and obtaining excavation samples or soil samples from the ground, and likewise using the device according to the invention for carrying out the method, excavation samples or soil samples can be obtained in almost original condition, allowing optimal evaluation and analysis of their contents. [Explanation of symbols]

[0043] 1 Hammer drill output shaft 2 Hydraulic drill drive for hammer drill 3 Screw of output shaft 1 4. Drilling System 5 Drill Head 6 Axial bore in drill head 7 Radial bores (vent holes) in drill head 8 Initial tube 9 Drill pipe, drill pipe extension 10 drill bits 11 Male thread at the bottom of the drill pipe / extension pipe 9 12 Female thread at the top of the drill pipe / extension pipe 9 13 Tungsten carbide tipped drill bit segments 14 Bevel surface of element 15 under excessive weight 15 Stripping Elements 16 Radial protruding heel 17 Sleeve, Drill Core Catcher 18 Pressure, flushing, and recovery pipe adapters 19 Pressure, flushing, and recovery pipes 20 Spring steel element at the lower inner edge of the core catcher 17 21 Sleeve adapter between pressure, flushing and recovery pipe and sleeve / drill core catcher 17 22 Base on the top of the sleeve adapter 21 23 Locating ring for sleeve adapter 21 24 Lower part of sleeve adapter 21 25 Sliding sleeve for sleeve adapter 21 26 Preferably a DIN471-65 x 2.5 circlip 27 Bottom rubber washer for sleeve adapter 21 28 Washer for sleeve adapter 21 29 Steel washer at the bottom of sleeve adapter 21 30 spring washers, preferably DIN128-A8 31 Screws, preferably hexagonal screws with threads on the head ISO4017-M8 x 20 32 Parallel pin, preferably NW8 x 25 mm with internal thread M5 33 Thrust ring to sleeve adapter 21 34 Rock bolt with pressure ball 40 35 Threaded stub at top of sleeve adapter 21 36 Upper seal ring preferably made from plastic hard rubber 37 Axial bore of drill head 5 38 Hole for lock bolt 34 39 Circlip / Seagull Ring for Lock Bolt 34 40 Pressure-loaded ball in front of rock bolt 34 41 radial bores all around the fixed positioning ring 23 of the sleeve adapter 21 42 radial bores all around the fixed lower portion 24 of the sleeve adapter 21 43 Hole in the bottom of the fixed type for the fixing bolt 48 44 Shoulder on the top of the base 22 of the sleeve adapter 21 45 Annular groove at the bottom of the base 22 46 Diameter hole in the top of the sleeve 17 47 Drive flange on drill head 5 48 Fixing bolt at the bottom 24 of the sleeve adapter 21 49 Horizontal hole of fixing bolt 48 50 Vertical groove of fixing bolt 48 51 Axial bore in the lower part 24 of the sleeve adapter 21 for flushing water 52 inner wall of the axial bore in the pressure, flushing, and recovery adapter 18 53 Pressure, flushing, and salvage pipe sections such as extension pipes 54 O-ring groove in pressure, flushing, and salvage pipe adapter 18 55 Axial hole of fixing bolt 48 56 Partial recess along the longitudinal groove 50

Claims

1. 1. A method for core drilling and obtaining samples from hard as well as loose ground, comprising: a starter tube (8) drilled into the ground by a drilling system (4) by means of rotary and overlapping ramming, the drilling system (4) comprising the starter tube (8) and a drill bit (10) fastened to the starter tube (8) at its bottom, and a drill pipe (9) consisting of one or more drill pipe sections and attachable to the starter tube (8), inside which a sleeve (17) or drill core catcher advances axially together with the starter tube (8); a) The initial pipe (8) with the drill bit (10) arranged at the end and the drill pipe (9) are drilled into the ground when rotated and hammered by a drivable drill head (5) capable of receiving a hammer impact force, and the sleeve (17) of the initial pipe (8) is held by the initial pipe (8) without rotating as a result of the drill core relatively increasing in the sleeve (17) and is pushed down from above by a pressure, flushing and recovery pipe (19), so that the sleeve (17) moves axially together with the initial pipe (8). the drill core moves downwards, and thus the drill core builds up inside the sleeve (17), and the pressure, flushing and recovery pipe (19) either rotates together with the initial pipe (8) and the drill pipe (9), or pressurizes the sleeve (17) without rotating by a sleeve adapter (21) with parts that can rotate relative to each other or a rotating disc body when a drill head adapter rotates on top and is connected to the drill head (5), and the pressure, flushing and recovery pipe (19) pressurizes the sleeve (17) without rotating; b) after the sleeve (17) has been filled, the drill head (5) lifts the initial pipe (8) or the drill pipe (9) and unscrews any drill pipe (9) that is above the initial pipe (8) and still above the bottom, so that the pressure, flushing and recovery pipe (19) is exposed and pulled out together with the sleeve (17) from the initial pipe (8), and the sleeve (17) is removed from the pressure, flushing and recovery pipe (19).

2. After step b), c) an empty sleeve (17) is connected at its bottom to the pressure, flushing and recovery pipe (19), suspended on the pressure, flushing and recovery pipe (19) and lowered into the initial pipe (8), and depending on the drilling depth, one or more sections of the pressure, flushing and recovery pipe (19) are inserted as extension pipes (53), and accordingly one or more drill pipe sections of the drill pipe (9) are inserted and coupled to the drill head (5); d) drilling continues until the sleeve (17) is filled, and after step d) step b) is repeated; 2. The method according to claim 1, characterized in that in parallel with these processes or with a time delay, the drill core is mechanically, hydraulically or pneumatically removed from the recovered casing (17) in a horizontal position of the casing (17) into a suitable horizontal pipe section.

3. 3. The method according to claim 1 or 2, characterized in that at the lower end of the sleeve (17), a spring steel element (20) initially oriented toward the center and inside the lower mouth area swings as the drilling sample rotates and grows inside the sleeve (17) when the sleeve (17) is on the bottom side, and the spring steel element (20) holds the drill core in the sleeve (17) when it is pulled out of the sleeve (17).

4. Method according to any one of claims 1 to 3, characterized in that no fixing rod is provided for retaining said sleeve (17).

5. 5. The method according to any one of claims 1 to 4, characterized in that the initial pipe (8) and any drill pipes (9) and the pressure, flushing and recovery pipes (19) are connected and disconnected by screwing and unscrewing the drill head (5), which is mechanically driven by a rotary drive.

6. 10. A device for carrying out the method according to claim 1, comprising a rotary drive with a rotatable drilling head (5) that can be impacted from above by a pile driver and a torque that can be transmitted to an initial pipe (8) with a drill bit (10) arranged at the end and to a drill pipe (9) consisting of one or more drill pipe sections connected to the initial pipe (8) at its upper part, inside the initial pipe (8) a sleeve (17) or bore core catcher, respectively, provides flushing without rotation, whereby the sleeve (17) is connected to the drill head (5) with a pressure lock and a traction lock by a sleeve adapter (21) having parts that can rotate relative to each other and pressure, flushing and recovery pipes (19) connected to the parts, Thus, either the pressure, flushing and recovery pipes (19) are connected to the drill head (5) by rotating at the same speed, and the sleeve (17) can be impacted by the pressure, flushing and recovery pipes (19) via the sleeve adapter (21) that is detachable from the sleeve (17), or the pressure, flushing and recovery pipes (19) are connected to the drill head (5) without rotating, and the sleeve (17) can be impacted by the pressure, flushing and recovery pipes (19) by pressure, while a rotating disc body is installed on top of the pressure, flushing and recovery pipes (19) as a drill head adapter with mutually rotatable parts and connected to the drill head (5).

7. 7. The device according to claim 6, characterized in that the sleeve (17) is mounted at its lower end to the upper end of the drill bit (10), which rotates freely along the bottom of the initial tube (8), in contact with a protrusion (16) projecting radially inward.

8. 8. A device according to claim 6 or 7, characterized in that no fixing rod is provided to hold the sleeve (17).

9. 9. A device according to any one of claims 6 to 8, characterized in that the sleeve (17) has, in the lower mouth area, a spring steel element (20) projecting into the interior for retaining the received drill core.

10. 10. A device according to any one of claims 6 to 9, characterized in that the sleeve adapter (21) or the part of the rotary disc body which can rotate relative to each other is axially continuous with the drill head adapter and has an interposed sealing ring (36) of plastic hard rubber.

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