Kelly bar, drilling device, and method for producing a drill hole in the ground

Abstract

The invention relates to a Kelly bar for transmitting a drilling torque from a drilling drive comprising an annular drive element, the Kelly bar comprising: a rod-shaped main body; driver strips which are situated on the outer circumferential face of the rod-shaped main body and are designed to receive the drilling torque from the annular drive element of the drilling drive; and a cable holder for connection to a support cable. In order to reduce sound radiation, the Kelly bar has at least one receiving chamber for receiving a damping fluid which reduces sound radiation from the Kelly bar during operation.

Description

[0001] 11} whimsical & home

[0002] the patent attorney

[0003] B 3940

[0004] KELLY ROD, DRILLING DEVICE AND METHOD FOR CREATING A HOLE IN THE GROUND

[0005] The invention relates to a Kelly bar for transmitting a drilling torque from a drilling drive with an annular drive element, comprising a rod-shaped base body, drive strips arranged on the outer circumferential side of the rod-shaped base body and designed to receive the drilling torque from the annular drive element of the drilling drive, and a rope holder for connecting to a support rope, according to the preamble of claim 1.

[0006] A Kelly bar is a one- or multi-section drill string that has been used for many decades in drilling boreholes in the ground. A Kelly bar can consist of a single drill rod or, preferably, of an outer tubular body, also called the outer kelly, in which one or more inner rods, also called inner or middle kelly, are telescopically arranged.

[0007] Such a Kelly bar allows a drilling tool to be suspended from a support cable, with torque being transmitted via the Kelly bar from a drill drive on a drilling rig. The drill drive can be ring-shaped, with the Kelly bar projecting through an annular drive element featuring torque-transmitting projections and / or recesses. Torque can be transmitted via corresponding, axially extending drive bars on the outside of the Kelly bar, allowing the drill string to be axially displaceable relative to the rotary drive. Axial forces can also be transmitted to the Kelly bar via locking pockets. By means of a preferably telescopic arrangement of one or more inner Kelly string elements with additional drive bars, drilling to greater depths can also be achieved by extending the Kelly bar accordingly.The torque is transmitted from the outer Kelly bar element to the next adjacent inner Kelly bar element via axial drive strips. Due to the design, there is a certain amount of play between the ring-shaped drive element and the outer surface of the Kelly bar with the drive strips, or between the individual linkage elements, to ensure sufficient movement.

[0008] Kelly bars are typically used for discontinuous drilling, for example with a drill bucket or auger, referred to here as the drilling tool. Once the drilling tool is filled with excavated soil after a drilling step, it is withdrawn from the borehole. The drilling tool is then moved outside the borehole to an emptying position, typically by pivoting, where the auger is emptied by a reversing rotary motion, a process known as shaking. A drill bucket is emptied by opening a hinged bottom, and for reliable emptying, especially with cohesive soil, it is common practice to assist the emptying process by shaking.

[0009] Particularly during such a dewatering process involving vibration, significant noise emission can occur from the telescopic drill string. This is because, due to the inherent play in the rod, the axial stop strips on the outside of the Kelly bar can strike the drill drive or the individual Kelly bar sections against each other during the vibration motion.

[0010] Particularly during construction work within cities, noisy work is undesirable. Such work may be prohibited above a certain noise level, or time restrictions may apply.

[0011] To reduce noise emission from a Kelly bar, it is known, for example, from DE 4041 303 C2, to provide it with sound-absorbing damping elements in cavities and along its circumference. However, due to functional limitations, such soft damping elements can only be arranged at certain points, so that comprehensive sound insulation is not achieved. From EP 4 390 054 A1, it is known that the at least two linkage elements of a telescopic Kelly bar, in an axially retracted state, are clamped or subjected to force in the circumferential direction against each other such that, in particular, the adjacent drive strips are either pressed against each other or kept at a distance in the circumferential direction. This ensures that the Kelly bar elements, which are guided with a certain amount of play due to operational requirements, are held in a fixed position relative to each other and thus, in particular, can no longer or hardly at all collide with each other during reversing rotation.

[0012] The invention is based on the task of providing a telescopic drill string in which a reduction in noise generation during operation can be achieved.

[0013] The problem is solved by a telescopic drill string with the features of claim 1. Preferred embodiments of the invention are specified in the dependent claims.

[0014] According to the invention, the Kelly bar is characterized in that it has at least one receiving chamber for receiving a damping fluid, which reduces sound radiation from the Kelly bar during operation.

[0015] A fundamental aspect of the invention is to form at least one receiving chamber in or on the Kelly bar for receiving a damping fluid. A damping fluid can absorb vibrations of the metallic Kelly bar during operation and thus reduce vibrational energy. This reduces the sound radiation from the Kelly bar.

[0016] The damping fluid also increases the mass of the Kelly bar, which further reduces its vibration and thus its sound radiation. One or more receiving chambers can be located at any suitable point along the Kelly bar. The receiving chamber can be completely or partially filled with the damping fluid.

[0017] A preferred embodiment of the invention consists in the base body being tubular and having at least one inner rod mounted therein so as to be axially displaceable and extendable. The Kelly bar is designed as a multi-section telescopic Kelly bar. Particularly with such multi-section Kelly bars, increased sound radiation from the Kelly bar elements, which can collide with each other during operation, occurs. Especially with such a multi-section Kelly bar, the arrangement of one or more receiving chambers with a damping fluid can lead to a significant reduction in sound radiation during operation.

[0018] According to a further development of the invention, it is preferred that at least one receiving chamber extends at least along an axial section in or on a wall of the base body and / or the at least one inner rod. The at least one receiving chamber can extend annularly around the circumference or only over a partial section of the circumference. In axial length, the receiving chamber can extend over the entire axial length or only over an axial section. In particular, several receiving chambers could be arranged at locations critical for sound radiation on the base body or one of the inner rods. The at least one receiving chamber can be formed on an outer or inner surface of the base body or an inner rod, or by a corresponding recess within the wall of the base body or an inner rod.

[0019] In principle, the receiving chamber can be designed like a pocket, with a lower section that is fluid-tight, while an upper section has at least one opening. It is also conceivable that, when the Kelly bar is operated in a fluid-filled borehole, the fluid from the borehole could selectively fill the receiving chamber, thereby reducing the sound emission in a controlled manner.

[0020] According to one embodiment of the invention, it is advantageous that the at least one receiving chamber is filled with the damping fluid and preferably sealed in a fluid-tight manner. This allows particularly suitable damping fluids to be accommodated in the at least one receiving chamber. These can preferably be completely enclosed in a fluid-tight manner. This allows for a very targeted and defined reduction of sound radiation. In a multi-section Kelly bar, it is also advantageous according to a further embodiment of the invention that the passage area of ​​an inner bar, also called an inner kelly, is sealed downwards from the base body and / or an adjacent inner bar, in particular by means of a ring seal.Thus, a space between the base body and an internal inner rod, or between two nested inner rods (one of which can also be called a center rod or center kelly), can serve as a receiving chamber, sealed at least at the bottom by a ring seal. The ring seal allows axial movement of the two Kelly bar elements relative to each other without preventing any significant amount of fluid from escaping through the corresponding passage area of ​​the Kelly bar elements. In particular, such an intermediate or cavity within the Kelly bar can be filled with damping fluid. This not only reduces sound radiation but also dampens the impact of, for example, drive strips or other sections of the Kelly bar elements against each other, which also has a positive effect on the overall sound generation and radiation of the Kelly bar.In the case of three- or more-part Kelly bars with a base body as a so-called outer kelly or outer bar and an innermost inner bar / inner kelly, all intermediate tubular inner bars can also be referred to as middle kellies or middle bars.

[0021] In multi-section Kelly bars, torque and / or force transmission to or between the inner sections can occur through positive locking, particularly via axially extending drive strips or locking pockets, and / or through frictional locking. If axial force transmission occurs solely or primarily through frictional locking, such Kelly bars are also referred to as friction Kelly bars.

[0022] A further advantageous embodiment of the invention lies in the fact that the base body is bell-shaped and is sealed fluid-tight at least at the top. In the case of a one-piece Kelly bar, a hollow Kelly bar can thus be formed, the inner cavity of which is sealed at the top and bottom and can therefore serve as a receiving chamber for a damping fluid. Compared to a solid Kelly bar, such a hollow Kelly bar, when filled with a damping fluid in the cavity or receiving chamber, can lead to a significant reduction in sound radiation. Similarly, in the case of a multi-piece Kelly bar, the bell-shaped, sealed upper design of the base body can form an inner receiving chamber, closed at the top and bottom, for receiving the damping fluid.

[0023] In principle, the at least one receiving chamber can be filled only once during the manufacturing of the Kelly bar. According to one embodiment of the invention, it is particularly advantageous that at least one filling and / or emptying opening is provided, which can be closed. A damping fluid can be filled or refilled into the receiving chamber at any time via a filling opening. The filling device is preferably located in an upper region of the receiving chamber. It can, in particular, be a closable inlet valve. Similarly, an emptying opening with a closable valve can be provided in a lower region of the receiving chamber. This allows the damping fluid to be selectively drained from a receiving chamber, for example, for transport or maintenance purposes.

[0024] In principle, any suitable free-flowing fluid that has a positive effect on the overall vibration behavior of the Kelly bar can be used to fill the recording chamber. The damping fluid can be, in particular, a liquid, a suspension containing solid particles, a gel, a paste-like mass, a free-flowing bulk material, or another free-flowing continuum. It can also be a gas with a density heavier than air.

[0025] According to a further development of the invention, it is particularly advantageous that the damping fluid comprises water and / or an oil, in particular a biodegradable oil and / or a gel and / or a paste-like mass. Water is a particularly cost-effective and environmentally friendly damping fluid, as well as readily and quickly available. In principle, other liquids can also be used, especially those with a higher density than water. Generally, the higher the density of a damping fluid, the stronger the damping effect. In particular, the damping fluid can be an oil, preferably a biodegradable one. High environmental compatibility is of paramount importance, especially when used in sensitive areas, such as groundwater-bearing soil layers.

[0026] Besides a liquid, another flowable material with a higher viscosity, in particular a gel or other pasty mass, can also be used as a damping fluid. These materials must also be securely contained within a receiving chamber, as otherwise they could not be reliably retained even with significantly reduced flowability.

[0027] Otherwise, the Kelly bar can be designed like a generally known Kelly bar, for example with a bracket for a support cable on the base or an inner rod. Furthermore, one or more rotary feedthroughs for conveying fluids, electrical current, or data can be arranged. Likewise, a clamping device known from the prior art can be used to axially clamp the individual Kelly bar elements against each other, in order to reduce or ideally completely prevent the generation of noise-causing vibrations by increasing positional stability.

[0028] According to a further development of the invention, it is preferred that a drilling tool for removing and / or displacing soil material is arranged at a lower end. The drilling tool can, in particular, be an auger, a drilling bucket, or a displacement drill.

[0029] The Kelly bar according to the invention can, in principle, be used on any construction machine that requires a Kelly bar. In a particularly preferred embodiment, the invention comprises a drilling rig for drilling into earth or rock, with a drilling drive having an annular drive element for transmitting drilling torque to a Kelly bar, wherein a Kelly bar designed according to the invention is arranged. Particularly when carrying out a discontinuous drilling process, for example with a drill bucket or auger, the drilling tool must be withdrawn from the ground several times and emptied at a discharge position by shaking or shocking. Especially during these noise-generating processes, a noticeable reduction in sound emission can be achieved by means of the Kelly bar according to the invention. In principle, the drilling rig can be designed in any suitable manner.A particularly advantageous aspect of the invention is that the drilling rig comprises a carrier unit with a mast along which the drilling drive is slidably arranged. The Kelly bar can project through the annular drive element of the drilling drive, with torque transmission occurring via interlocking drive bars. Locking pockets can be arranged at suitable locations on the drive bars, so that when the Kelly bar is axially locked relative to the drilling drive, or individual Kelly bar elements are locked relative to each other, an axial force can be exerted from the drilling drive on the Kelly bar and thus on a drilling tool. For this purpose, a corresponding traverse drive for the drilling drive can be arranged on the mast.

[0030] According to one embodiment of the invention, particularly flexible use of a drilling rig is achieved by making the carrier unit mobile, in particular by having a tracked chassis. A self-propelled carrier unit thus enables mobile use of the drilling rig on a construction site.

[0031] The invention further comprises a method for creating a borehole in the ground, wherein the borehole is formed using a drilling rig according to the invention. According to one embodiment of the invention, it is particularly advantageous that the borehole is filled with a fill material to form a foundation element in the ground. The fill material can be, for example, sand, gravel, or a hardenable compound. Pile-shaped foundation elements can be formed to support structural loads or to create a bored pile wall in excavation pits.

[0032] The invention is further described below with reference to preferred embodiments, which are shown schematically in the drawings. The drawings show:

[0033] Fig. 1 shows a schematic side view of a drilling rig with a drill string according to the invention;

[0034] Fig. 2 a perspective view of a Kelly bar in the retracted state; Fig. 3 a perspective view of a Kelly bar in the extended state;

[0035] Fig. 4 shows an enlarged detail view of an upper area of ​​a Kelly bar according to the invention;

[0036] Fig. 5 shows an enlarged detail view of a lower region of a Kelly bar according to the invention; and

[0037] Fig. 6 shows a comparison diagram of sound radiation.

[0038] A drilling rig 10 with a Kelly bar 30 according to the invention, preferably telescopic, is shown in Fig. 1. A carrier unit 11 of the drilling rig 10 can preferably have a movable undercarriage 12, which in the example shown is designed as a crawler chassis, and a superstructure 13 rotatably mounted thereon. A mast 16, which is essentially vertical in operation, can be adjustably articulated via a linkage mechanism 14, which can include articulated levers and actuating elements.

[0039] A linear mast guide 19 can be formed on a front side of the mast 16, along which a sliding carriage 17 with a drilling drive 18 can be mounted and moved vertically by means of a feed winch 22.

[0040] Preferably, a support cable 28 can be guided over a mast head of the mast 16, with the Kelly bar 30 suspended at the free end of the support cable 28 by a cable holder 32. The Kelly bar 30 passes through the ring-shaped drill drive 18, with a drill bit 20 detachably attached to the lower end of the Kelly bar 30. The drill bit 20 is exemplified as a drill auger, which, in its raised position, can be surrounded by a cylindrical cage with holes. The cage can prevent, for example in granular soils, the loss or slippage of soil material from the drill auger 20 before emptying at a defined emptying position. A ring collar 70 can be arranged at an upper end region of the Kelly bar 30, with which the Kelly bar 30 can be placed onto the drill drive 18.

[0041] Figures 2 and 3 show a Kelly bar 30 according to the invention, which, according to the exemplary embodiment, is preferably telescoping. Figure 2 shows the Kelly bar 30 in a retracted state, and Figure 3 shows it in an extended or telescoped state. However, the invention can also be applied to one-piece Kelly bars.

[0042] The Kelly bar 30 according to the illustrated embodiment has a tubular base body 31 with outer drive strips 34, which can engage with corresponding inner drive strips or recesses of an annular drive element of the drill drive 18 for torque transmission. Preferably, one or more locking pockets 35 can be formed on the outer drive strips 34, through which an axial force can also be exerted downwards on the Kelly bar 30 via the drill drive 18 when appropriately locked.

[0043] For mounting on the drill drive 18, a ring collar 70 can be formed at an upper end region of the Kelly bar 30 in a generally known manner. A rope holder 32, shown only in Figure 2, can also be formed at the upper end of the Kelly bar 30 for connection to the support cable 28.

[0044] As shown in Fig. 3, the Kelly bar 30 is designed to be double-telescoping, comprising an inner Kelly bar 50 with first outer drive strips 52 and a middle Kelly bar 60 with second outer drive strips 62, which is arranged between the inner Kelly bar 50 and the outer base body 31 (also called the outer Kelly bar in the case of multi-section Kelly bars). The respective drive strips 52, 62 of the inner and middle Kelly bars 50, 60 interact with the adjacent inner strips (not shown) of the Kelly bar elements to transmit the drilling torque. In this way, a drilling torque can be transmitted from the drill drive 18 to a drill bit 20 attached to the Kelly bar 30.

[0045] According to the illustrated embodiment of a Kelly bar 30, a damping element 38 and a connecting device 36 with a square pin 37 are formed at the lower end of the Kelly bar 30, in particular at the inner kelly 50. The drilling tool 20 has a corresponding receptacle for the square pin 37 on its upper side, so that a torque-transmitting connection between the Kelly bar 30 and the drilling tool 20 can be formed by means of a corresponding locking mechanism via at least one transversely oriented locking bolt.

[0046] Figure 4 shows an upper section of the Kelly bar 30 in a retracted state, in which the inner kelly 50 and the center bar 60 are arranged in an upper section within the tubular base body 31. The essentially tubular inner kelly 50 can have a sealing cap 66 at its upper end, which ensures that the interior of the inner kelly 50 is tightly sealed at the top. The cable bracket 32 ​​can be attached to the sealing cap 66, with which the inner kelly 50, and thus the entire Kelly bar 30, can be suspended from the support cable 28.

[0047] Furthermore, an annular sealing collar 67 can be located on the closure cover 66, which is arranged to seal and be displaceable against an annular sealing attachment 33 at the upper end of the outer base body 31 of the Kelly bar 30. In the retracted state shown in Fig. 4, an inner receiving chamber 40 within the Kelly bar 30 can thus be sealed tightly at the top.

[0048] Furthermore, one or more filling openings 48 can be located at the upper end region of the base body 31, preferably at the sealing attachment 33. A damping fluid can be introduced into the receiving chamber 40 within the Kelly bar 30 via the at least one filling opening 48. The at least one filling opening 48 is preferably closable.

[0049] A lower section of the Kelly bar 30, and in particular a first downward passage 55 of the inner Kelly bar 50, is illustrated in Fig. 5. The inner Kelly bar 50 has a cylindrical sealing section 54 at its lower end, which is slidably but tightly abuts a lower end ring 42 with internal second sealing elements 43. The lower end ring 42 is arranged at the lower end of the central rod 60, so that the area of ​​an upper receiving chamber 40 in the Kelly bar 30 is sealed tightly at the bottom. A second passage between the base body 31 and the central rod 60 can also be sealed downwards in a corresponding manner. The lower damping element 38, which in the illustrated embodiment is formed by a stack of disc springs, can be connected to the lower end ring 42.

[0050] Figure 6 shows a comparison of the sound power of a conventional Kelly bar, called a "Kelly," versus a Kelly bar according to the invention, filled with water, which is referred to as a "water Kelly." The diagram in Figure 6 shows the sound power W in dB(A) as a function of the Kelly bar's oscillation frequency. It is particularly evident that in a relevant frequency range between approximately 40 Hz and approximately 10,000 Hz, there is a significant reduction in the emitted sound power of a Kelly bar filled with water according to the invention compared to a conventional Kelly bar. In particular, in the especially relevant frequency range between 200 Hz and 2,000 Hz, a reduction in sound power of up to 10 dB is possible, which, with regard to the logarithmic representation of sound power, corresponds to approximately a halving of the noise exposure.

[0051] A 3 dB reduction already halves the sound power level. A 10 dB reduction halves the perceived loudness.

Claims

11} whimsical & home i IPATENTANWÄ LTE - 13 - B 3940 PATENT CLAIMS 1 Kelly bar for transmitting a drilling torque from a drilling drive (18) with an annular drive element, with a rod-shaped base body (31 ) Drive strips (34), which are arranged on the outer circumferential side of the rod-shaped base body (31) and are designed to receive the drilling torque from the ring-shaped drive element of the drilling drive (18), and a rope holder (32) for connecting to a support rope (28), characterized in that , that the Kelly bar (30) has at least one receiving chamber (40) for receiving a damping fluid, which reduces the sound emission of the Kelly bar (30) during operation. Kelly bar according to claim 1 , characterized by , that the base body (31) is tubular in shape and has at least one inner or middle kelly (50, 60) mounted therein in a manner that is axially displaceable and extendable. Kelly bar according to claim 1 or 2, characterized by , that at least one receiving chamber (40) extends at least along an axial subsection in or on a wall of the base body (31) and / or the at least one inner or middle kelly (50, 60).

4. Kelly bar according to one of claims 1 to 3, characterized by , that the at least one receiving chamber (40) is filled with the damping fluid and is preferably sealed in a fluid-tight manner.

5. Kelly bar according to one of claims 1 to 4, characterized by , that at least one receiving chamber (40) is formed in an intermediate space between the outer base body (31) and the at least one inner or middle kelly (50, 60).

6. Kelly bar according to one of claims 2 to 5, characterized by , that a passage area (55, 65) of an inner or middle kelly (50, 60) is sealed downwards against the base body (31) and / or an adjacent inner or middle kelly (50, 60), in particular by means of at least one ring seal (46).

7. Kelly bar according to one of claims 1 to 6, characterized by , that the base body (31) is bell-shaped and is sealed fluid-tight at least at the top.

8. Kelly bar according to one of claims 1 to 7, characterized by , that at least one filling opening (48) and / or emptying opening is provided which is closable.

9. Kelly bar according to one of claims 1 to 8, characterized by , that the damping fluid comprises water and / or an oil, in particular a biodegradable oil.

10. Kelly bar according to any one of claims 1 to 9, characterized by , that a drilling tool (20) is arranged at a lower end for removing and / or displacing soil material.

11. Drilling rig for drilling into earth or rock, with a drilling drive (10) having an annular drive element for transmitting a drilling torque to a Kelly bar (30), characterized by , that a Kelly bar (30) is arranged according to one of claims 1 to 10.

12. Drilling device according to claim 11 , characterized by , that this has a carrier device (11) with a mast (16) along which the drilling drive (18) is arranged to be displaceable.

13. Drilling device according to claim 12, characterized by , that the carrier device (11) is movable, in particular has a tracked chassis.

14. Method for creating a borehole in the ground, characterized by , that the borehole is formed with a drilling device (10) according to one of claims 11 to 14.

15. Method according to claim 14, characterized by , that the borehole is filled with a filling material to form a foundation element in the ground.

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