EP2984273B1 - Method for the chisel-less formation of boreholes for deep bores and chisel-less drilling system for carrying out said method - Google Patents

Description

The invention relates to a method for chisel-free creation of wells for deep wells by means of high-pressure water jet cutting. Furthermore, the invention relates to a chisel-free drilling system for carrying out the method.

The creation of boreholes for vertical deep wells, that is holes that are driven into a depth of over 500 m in the ground, takes place in practice according to the so-called Rotary method in which by means of a rotating bit, the rock to be pierced schabend crushed is continuously discharged through a flushing liquid, which is pumped down through the drill pipe.

For very deep wells usually a drilling turbine is used, which is located directly above the drill bit. The drill string adjoining the drill bit counter to the drilling direction does not rotate with the drill bit in this method, but only serves for the bit feed and the supply of the rinsing liquid.

Drill bits with diamond or tungsten carbide fillings have a shelf life of 70 to 100 hours under normal soil conditions. Then, to replace and refurbish the drill bit, the entire drill string must be pulled out of the wellbore and disassembled to subsequently be lowered back into the wellbore with the new drill bit. Thus, in the conventional deep drilling method results in a discontinuous course of the drilling process.

To prevent the wellbore from collapsing, the wellbore must be supported, which is done by conventional tubing drilling. This is done in stages with decreasing pipe diameter such that, for example, at a depth of 3000 m deep oil well, a first reaching to a depth of 5 m pipe with an outer diameter of 473 mm is introduced. After a drilling depth of 150 m, a casing or casing called a 340 mm outer diameter is pushed in to the bottom of the hole and the gap between the borehole wall and the casing is filled with cement slurry. At a drilling depth of 1500 m and a final depth of 3000 m, further casings with casing pipes each have a smaller outer diameter than the previous casing pipes, so that the outer diameter of the last casing after reaching the final depth is only 140 mm.

Although this known deep drilling method has proven itself in practice, however, the costs for such deep drilling are extremely high due to the discontinuous drilling and the continuous processing or re-provision of the drill bit and the drill string.

A generic alternative deep drilling method is for example from the DE 10 2010 005 264 A1 Known in which the creation of the wellbore is done chiseless by means of water jet cutting. Drilling head for carrying out this known method is annular and has a plurality of juxtaposed water outlet nozzles. With this annular drill head, only a rock formation, but not the entire borehole diameter, is comminuted in the manner of a core drilling machine. After reaching a predeterminable depth of 5 m or 10 m radially inwardly facing water outlet nozzle are activated on the drill head to radially cut free the core along its outer surface exposed core. Then the cut core is pulled up out of the hole. The lining of the borehole takes place in this known method via a respective arc of 120 ° spanning sub-segments.

Also, this chisel-free drilling process works discontinuously, as the cut cores each have to be removed from the well. In addition, the borehole must have a very large minimum diameter to to have the appropriate scope for the transport of the cores.

The US 3,251,424 relates to a method and apparatus for drilling a well into the earth by means of high velocity water jets. The water jets are generated in the form of pulses with alternating high and low acoustic pressures and passed into the soil to be removed. The flushing medium is supplied from outside the borehole (passive boring head). The flushing medium is increased in terms of its discharge pressure due to the passage through holes, but is only at 6,700 psi, which corresponds to about 462 bar. Thus, by means of the method and by means of the device of US 3,251,424 Soil can be flushed out of a well. A water jet cutting can not be carried out in this way, however, because pressures from 4,000 bar are needed for this purpose. These can not be provided.

On this basis the invention has for its object to provide a process for the chisel without creation of holes for deep wells, that a substantially continuous drilling operation possible.

The solution to this problem is inventively characterized by a combination of the process high-pressure water jet cutting with high-frequency Steinzertrümmerung.

High-pressure water jet cutting is understood to mean the cutting or severing of the rock with a jet of water or several high-pressure water jets. Such water jets can have a pressure from 1,000 bar. Preferably, pressures of 4,000 to 6,000 bar are used. An abrasive can be added to the water in order to increase the cutting performance, which is preferably done only at pressures above 3,000 bar. These water jets reach discharge speeds of up to 1000 m / s.

The inventive combination of high pressure water jet cutting with high frequency stone fragmentation, it is possible to provide an efficient and continuous drilling method, wherein the high frequency stone fragmentation is alternately to high pressure water jet cutting or operated in parallel to use the most effective way, the break up the rock layer to be drilled.

In order to be able to optimally adapt the processes of high-pressure water jet cutting and high-frequency rock fragmentation to one another and to the conditions required locally in the borehole, the invention proposes that the pressures for the high-pressure water jet cutting process and the frequencies of the high-frequency rock fragmentation be variably adjusted are.

According to an advantageous embodiment of the method according to the invention, the inner wall of the borehole is continuous with a reinforcement, for example a fiber reinforced shotcrete, lined. As a result of this continuous lining of the borehole directly after boring, the entire boring process becomes even more efficient, as here too it is possible to dispense with interruptions, such as are required, for example, in the well-known casing of the boreholes.

A drilling system according to the invention for carrying out the chisel-free drilling method according to the invention is characterized in that sonotrodes for transmitting high-frequency vibrations are arranged on the front end side of the drill head in addition to the water outlet nozzles for the high-pressure water jet cutting.

According to a preferred embodiment of the invention, it is proposed that the drill head, or at least a front plate of the drill head provided with the water outlet nozzles and the sonotrodes, is designed to be rotatable about the central axis in order to produce a uniform and substantially full-surface treatment of the rock to be drilled over the entire borehole diameter to ensure.

With a practical embodiment of the embodiment of the drilling system according to the invention, it is proposed that at least one safety module and at least one borehole lining module be arranged in the drilling direction behind the drill head. Depending on the application, the individual components can be arranged rigidly or movably one behind the other relative to one another.

In the case of a sudden increase in pressure in the borehole, for example by the drilling of a gas bubble, on the one hand to prevent uncontrolled leakage of the gas from the well and on the other hand to prevent the entire drilling system can be pushed by the pressure increase upwards from the well, that Security module at least one locking element for positive locking of the bore hole inside diameter and clamping elements for non-positive fixing of the drilling system in the borehole.

The positive closure of the borehole diameter can be done, for example, with an expander ring which closes the borehole to the overpressure then be able to reduce controlled by suitable pressure valves. The clamping elements, with which the entire drilling system can claw in a non-positive manner in the borehole, are designed according to the invention, for example, as radially upwardly and outwardly pointing barbs which fix the drilling system in the respective position in the borehole.

To secure the well as well as to shield the well to groundwater leading layers, the well is continuously lined directly after drilling. For this purpose, the borehole lining module according to the invention has spray nozzles for applying a hardening medium, such as concrete, as well as a reinforcing fabric laying device. To form this lining of the borehole wall serving hybrid material consisting of a reinforcing fiber and a thermosetting medium preferably carbon fibers and concrete are used. The deployment of the fiber braid can be carried out according to the invention via a cone, via which the reinforcing fiber can be applied directly to the borehole wall, in order to be subsequently wetted with the hardening medium can. Depending on requirements, the lining of the borehole can be single-layered or multi-layered.

As an alternative to the mentioned carbon fibers and the concrete as a hardening medium, of course, other fibrous materials and other hardening media may be used to line the wellbore.

The supply of the drilling system according to the invention, consisting of the drill head, the safety module and the Bohrlochauskleidemodul advantageously via flexible pipe and / or hose lines through which the drilling system is connected to utilities outside the borehole, wherein the pipe and / or hose lines for supply and Removal of the drilling system related materials and to supply the electrical supply lines serve. Each individual line of this flexible pipe and / or hose lines is preferably designed as an endless line that can be kept ready on drums.

Furthermore, it is proposed with the invention that the drive and the steering and control device for the drill head are arranged directly on the drill head.

In order to make the drilling system according to the invention as independent as possible from outside the well arranged supply stations, according to a practical embodiment of the invention, the pumps for high pressure water jet cutting and for the suction of the flushing medium at the drill head and / or arranged on the security module.

In the flexible tubing and / or tubing through which the drilling system is connected to out-of-well utilities, in addition to the electrical supply lines are also data lines, e.g. a bus system via which the drill head and / or the safety module and / or the borehole lining module are connected to an out-of-well stand.

According to the invention, all environmental parameters in the borehole, such as temperature, pressure, rock density and the like, can be determined via the data lines in addition to the system parameters, such as feed rate and pump pressure, via sensors coupled to the data lines and can be transmitted to the workstation for controlling the drilling system.

Finally, it is proposed with the invention that for generating the high-frequency pulses for the high-frequency Steinzertrümmerung piezo elements are arranged in the drill head, which are each coupled to a consisting of a sonotrode and an amplitude transformer amplifying unit.

Due to the equipment of the drilling system with the piezoelectric elements and sonotrodes for generating the high-frequency pulses, it is possible after reaching the target drilling depth, using the high-frequency stone fragmentation the stone in the manner of fracking, but without breaking chemical use.

Fig. 1

eine schematische Seitenansicht eines erfindungsgemäßen meißellosen Bohrsystems;

Fig. 2

eine Vorderansicht des Bohrkopfes gemäß Fig. 1 und

Fig. 3

eine Ansicht gemäß Fig. 1, jedoch das Bohrsystem in einem Bohrloch zeigend.

Further features and advantages of the invention will become apparent from the accompanying drawings, in which an embodiment of a chisel-free drilling system according to the invention is shown only by way of example, without limiting the invention to this embodiment. In the drawings shows:

Fig. 1

a schematic side view of a chisel-free drilling system according to the invention;

Fig. 2

a front view of the drill head according to Fig. 1 and

Fig. 3

a view according to Fig. 1 but showing the drilling system in a borehole.

Fig. 1 shows a drilling system 1 for vertical deep wells, which consists essentially of a drill head 2, a safety module 3 and a borehole lining module 4, wherein the individual assemblies 2, 3 and 4, depending on the application, are arranged rigidly or movably one behind the other.

Even though vertical deep drilling is called for, with the method and drilling system 1 described below it is also possible to control the course of the drilling from the vertical to a horizontal course, if necessary. The main direction of drilling is the deep vertical hole.

As from the in Fig. 3 shown arrangement of the arranged in a borehole 5 drilling system 1, the supply of existing from the drill head 2, the safety module 3 and the Bohrlochauskleidemodul 4 drilling system 1 via flexible pipe and / or hose lines 6, via the drilling system 1 with utilities 7 outside of the borehole 5 is connected. The pipe and / or hose lines 6, which are used for supplying and discharging the drilling system 1 relevant materials and for supplying the electrical supply lines, the individual pipe and / or hose lines 6 are formed as an endless line that can be kept on drums.

The individual pipe and / or hose lines 6 are connected at intervals with spacers and thus form a supply line, which is guided into the borehole 5. In order to absorb the tensile forces that arise due to the weight of the pipe and / or hose assemblies 6 and the weight of the drilling system 1, steel cables are preferably carried, which are stored outside of the borehole 5 accordingly. Furthermore, it is possible to specify floating body to the pipe and / or hose assemblies 6, the absorb the tensile load, since the borehole 5 is under water during the drilling process.

How out Fig. 2 can be seen, water outlet nozzles 8 for the high-pressure water jet cutting and sonotrodes 9 for transmitting high-frequency vibrations for the high-frequency stone fragmentation are arranged on the front end side of the drill head 2.

In order to ensure uniform and substantially full-surface machining of the rock to be drilled over the entire borehole diameter, the entire boring head 2, or at least a face plate 10 of the boring head 2 provided with the water outlet nozzles 8 and the sonotrodes 9, is rotatable about the central axis.

For sucking off the drilling mud accumulating during the drilling operation, suction openings 17 are provided in the face plate 10, via which the drilling mud can be sucked off and pumped out of the borehole 5 through the pipe and / or hose lines 6.

To generate the high-frequency pulses for the high-frequency Steinzertrümmerung piezo elements are arranged in the drill head 2, which are each coupled to a consisting of a sonotrode 9 and an amplitude transformer amplifying unit. In order to protect the sonotrodes 9 from wear, they are advantageously coated, for example with polycrystalline diamond.

The pumps for the high-pressure water jet cutting and for the suction of the flushing medium are arranged on the drill head 2 and / or on the security module 3. In order to increase the cutting action of the high-pressure water jet, an abrasive, such as quartz sand, can be added to the water jet, which is supplied to the drill head 2 via the flexible pipe and / or hose lines 6 and mixed with the water jet in the water outlet nozzle 8 To keep the wear on the lines as low as possible. The addition of the abrasive can be done continuously or only temporarily.

By combining the high-pressure water jet cutting with the high-frequency rock smashing, as well as by the planar design of the drill head 2 and the corresponding placement of the water outlet nozzles 8 and 9 sonotrodes, it is possible to carry out the drilling process continuously, that is without interruptions for the regeneration of a drill bit or for removing a cut core, as required in the prior art deep hole drilling method.

In order to be able to use a continuously operating drilling method as efficiently as possible, it is advantageous if the securing and lining of the borehole 5 can also take place essentially continuously.

To secure the borehole 5 as well as to shield the borehole leading to groundwater layers, the borehole 5 is lined directly after drilling. For this purpose, the borehole lining module 4 according to the invention has spray nozzles 11 for applying a hardening medium, such as concrete, as well as a reinforcing fabric laying device 12.

Preferably, carbon fibers and concrete are used to make the borehole lining lining, but other fiber materials and other hardening media, such as plastics, may also be used to make the hybrid material.

The Armierungsgewebeverlegevorrichtung 12 for deploying the fiber braid can be done for example via a cone over which the reinforcing fiber can be applied directly to the borehole wall, in order to be subsequently wetted with the hardening medium can. Depending on the depth and geological conditions, the lining of the borehole 5 can be single-layered or multi-layered. By adding special additives, the curing time of the concrete can be accelerated. In deeper regions with a higher earth temperature, the hardening time is shortened by the temperature rise alone. The mixing of the concrete supplied via the pipe and / or hose lines 6 with the additives also supplied via the pipe and / or hose lines 6 takes place only at the borehole lining module 4 in order to avoid hardening in the supply lines.

A finished well casing 18 is shown schematically in FIG Fig. 3 shown.

The safety module 3 serves, in the event of a sudden increase in pressure in the borehole 5, for example by drilling a gas bubble, on the one hand to prevent uncontrolled escape of the gas from the borehole 5 and on the other hand to prevent the entire drilling system 1 from rising due to the pressure rise the borehole 5 can be pushed. For this purpose, the security module 3 has at least one blocking element 13 for the positive closing of the inner diameter of the borehole as well as clamping elements 14 for frictional fixing of the drilling system 1 in the borehole 2.

The positive locking of the borehole diameter over the blocking element 13 can, for example, take place with an expander ring which closes the borehole 5 in order to then be able to reduce the overpressure in a controlled manner by means of suitable pressure valves. The clamping elements 14, with which the entire Bohrsystem1 can claw frictionally in the wellbore 5, for example, as radially upwardly and outwardly facing barbs are formed, which fix the drilling system 1 in case of need in the respective position in the borehole 5.

The drive and the steering and control device for the drill head 2 are arranged on the drill head 2. In the illustrated embodiment, the drive for the drill head 2 as arranged on the outside of the drill head 2 caterpillar drive 15 is formed.

In the flexible pipe and / or hose lines 6, via which the drilling system 1 is connected to supply devices 7 outside the borehole 5, in addition to the electrical supply lines there are also data lines, e.g. a bus system, via which the drill head 2 and / or the safety module 3 and / or the borehole lining module 4 are connected to a working stand 16 outside the borehole 5.

In addition to the system parameters, such as, for example, feed rate and pump pressure, via sensors connected to the data lines, all environmental parameters in the borehole 5, such as For example, temperature, pressure, rock density and the like, can be determined and transmitted to the control of the drilling system 1 to the workstation 16.

The control of the drilling system 1 can be arranged on only one of the components drill head 2, safety module 3 or borehole lining module 4 or distributed over a plurality of the components 2, 3 and 4.

In particular, since the drill head 2 has a larger outer diameter than the finish-lined hole 5, the complete drilling system 1 remains in the hole 5 after completion of the drilling operation and can be used after the capping of the supply lines via the existing data lines for data exchange with the workstation 16.

The drilling method described above, which is used for Geothermiebohrungen and for development of natural gas or Erdöllagerstätten is characterized by the fact that a continuous drilling process allows and dispensing with drill pipe and the like a much lower cost of materials than the known from the state of the art drilling needed, which leads to significantly lower prices for the creation of a deep well. <B><u> Bezudszeichenliste </ u></b> 1 Drilling System 18 well casing 2 wellhead 3 security module 4 Bohrlochauskleidemodul 5 well 6 Pipe and / or hose line 7 supply 8th water outlet 9 sonotrode 10 faceplate 11 nozzle 12 Armierungsgewebeverlegevorrichtung 13 blocking element 14 clamping element 15 Track drive 16 working status 17 suction

Claims (15)

1. Method for the chisel-less formation of boreholes for deep bores by means of high pressure water jet cutting, characterized by a combination of the high pressure water jet cutting process with high frequency rock fragmentation by sonotrodes.
2. Method according to Claim 1, characterized in that the high frequency rock fragmentation is used alternating with the high pressure water jet cutting or simultaneously with the high pressure water jet cutting.
3. Method according to Claim 1 or 2, characterized in that the pressures of the high pressure water jet cutting process and the frequencies of the high frequency rock fragmentation are variably adjustable.
4. Method according to one of Claims 1 to 3, characterized in that the wall of the borehole (5) is continuously lined with a reinforcement.
5. Chisel-less drilling system for carrying out the method according to one of Claims 1 to 4 with a drill head (2) provided with water outlet nozzles (8), characterized in that sonotrodes (9) for transmitting high frequency vibrations are arranged in addition to the water outlet nozzles (8) for the high pressure water jet cutting on the front end side of the drill head (2).
6. Chisel-less drilling system according to Claim 5, characterized in that the drill head (2), but at least an end plate (10) of the drill head (2), which end plate is provided with the water outlet nozzles (8) and the sonotrodes (9), is designed to be rotatable about the center axis.
7. Chisel-less drilling system according to Claim 5 or 6, characterized in that at least one safety module (3) and at least one borehole lining module (4) are arranged behind the drill head (2) in the drilling direction.
8. Chisel-less drilling system according to Claim 7, characterized in that the safety module (3) has at least one locking element (13) for the form-fitting closing of the inside diameter of the borehole, and clamping elements (14) for the force-fitting securing of the drilling system (1) in the borehole (5).
9. Chisel-less drilling system according to Claim 7, characterized in that the borehole lining module (4) has spray nozzles (11) for applying a curing medium, and a reinforcing fabric laying apparatus (12).
10. Chisel-less drilling system according to Claim 5, characterized in that the drill head (2), the safety module (3) and the borehole lining module (4) are connected to supply devices (7) outside the borehole (5) via flexible pipe and/or hose lines (6), wherein the pipe and/or hose lines (6) serve for the supply and removal of the materials relating to the drilling system (1) and for the feeding in of the electric supply lines.
11. Chisel-less drilling system according to one of Claims 5 to 10, characterized in that the drive and also the steering and control apparatus for the drill head (2) are arranged on the drill head (2).
12. Chisel-less drilling system according to one of Claims 5 to 11, characterized in that the pumps for the high pressure water jet cutting and for sucking off the flushing medium are arranged on the drill head (2) and/or on the safety module (3).
13. Chisel-less drilling system according to one of Claims 5 to 12, characterized in that the drill head (2) and/or the safety module (3) and/or the borehole lining module (4) are connected to a workplace (16) outside the borehole (5) via data lines, for example a bus system.
14. Chisel-less drilling system according to Claim 13, characterized in that, via the data lines, in addition to the system parameters, such as, for example, feed speed and pumping pressure, all of the ambient parameters in the borehole (5), such as, for example, temperature, pressure, rock density and the like, can be determined via sensors coupled to the data lines and can be transmitted to the workplace (16) in order to control the drilling system (1).
15. Chisel-less drilling system according to Claim 5, characterized in that, in order to generate the high frequency pulses for the high frequency rock fragmentation, piezo elements which are each coupled to an amplifying unit consisting of a sonotrode (9) and an amplitude transformer are arranged in the drill head (2).

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