Tunnel boring device and system for the hydraulic removal of cuttings, and system for producing a stable fluid pressure for a boring fluid in the region of a cutting disk of the tunnel boring device

Abstract

A tunnel boring device for laying a pipeline in the ground using a boring tool, having; a feed line for supplying a boring fluid to the boring tool; a section, arranged at the rear of the boring tool, for receiving the ground cuttings, wherein the region of the boring tool and the section are filled with boring fluid, with a pressure that corresponds to the pressure in the ground; at least a jet pump for removing the boring fluid mixed with the cuttings; at least one conveying line for removing the boring fluid mixed with cuttings, this line being connected to the delivery side of the pump connected to the section via a suction line. The jet pump is connected to a drive line via which a driving fluid is supplied to the jet pump; the pump is arranged outside then section; and the suction line contains a shutoff valve.

Claims

1. A tunnel boring device for creating a bore from a starting point to a target point in the ground along a predefined boring line by advancing the tunnel boring device in order to create a tunnel or in order to lay a pipeline in the ground using a boring tool to break up the ground, comprising; at least one feed line configured to supply a boring fluid to the boring tool; at least one section disposed on the rear side of the boring tool, configured to receive the broken-up ground which is present in the form of cuttings; at least one pump configured to remove the boring fluid mixed with the cuttings from the at least one section; at least one conveying line configured to remove the boring fluid mixed with cuttings from the bore, the conveying line being connected to a delivery side of the at least one pump; wherein a region of the boring tool and the at least one section are filled with boring fluid; wherein the boring fluid in the region of the boring tool and the boring fluid disposed in the at least one section are disposed with a pressure which corresponds to the pressure prevailing in the ground at a heading face; wherein the at least one pump is connected to the at least one section via at least one suction line; wherein the pump is a jet pump connected to a driving line via which a driving fluid is supplied to the jet pump; wherein the at least one pump is disposed outside the at least one section; and wherein at least one shut-off valve is disposed in the at least one suction line via which the suction line can be closed; wherein a connection line is disposed between the feed line and the suction line; wherein the connection line comprises a shut-off valve for closing off the connection line; wherein a shut-off valve is disposed in the feed line; wherein the connection line connects to the suction line between the shut-off valve in the suction line and the jet pump; and wherein the connection line connects to the feed line before the shut-off valve in the feed line.

2. The tunnel boring device as claimed in claim 1, wherein a control valve, from which the feed line leads away, is disposed in the driving line configured to set the volumetric flow of the boring fluid in the feed line.

3. The tunnel boring device as claimed in claim 1, wherein the pump is connected to a high-pressure pump via the driving line.

4. The tunnel boring device as claimed in claim 1, wherein at least one of the boring fluid or the driving fluid is a bentonite suspension.

5. The tunnel boring device as claimed in claim 4, wherein the bentonite suspension is utilized as a processed boring suspension in a circulating arrangement.

6. A system for the hydraulic removal of cuttings broken up by a tunnel boring device, comprising: a tunnel boring device configured for wet boring with heading face pressure regulation; a section for receiving the broken-up cuttings; a feed line for supplying boring fluid to the section; a suction line for removing boring fluid mixed with cuttings; a jet pump for removing the boring fluid mixed with cuttings; a driving line connected to a driving line connection of the jet pump, wherein driving fluid is conveyed to the jet pump by a driving pump; and a connection line between the feed line and the suction line; wherein the suction line, the feed line and the connection line each include at least one shut-off element; wherein the connection line connects to the suction line between the shut-off valve in the suction line and the jet pump; and wherein the connection line connects to the feed line before the shut-off valve in the feed line.

7. A system for producing a stable fluid pressure for a boring fluid in the region of a cutting disk of a tunnel boring device configured for wet boring at a heading face during the creation of a bore from a starting point to a target point in the ground along a predefined boring line by advancing the tunnel boring device to one of create a tunnel or lay a pipeline, wherein the tunnel boring device has a section behind the cutting disk for receiving cuttings released by the cutting disk, the system comprising: a feed line for supplying boring fluid to the heading face; a suction line for removing boring fluid mixed with cuttings from the section; a jet pump for removing the boring fluid mixed with cuttings; a driving line which is connected to a driving line connection of the jet pump, wherein driving fluid is conveyed to the jet pump by a driving pump; and a connection line between the feed line and the suction line, wherein at least one shut-off element is provided in each case in the suction line, the feed line and the connection line; wherein the connection line connects to the suction line between the shut-off valve in the suction line and the jet pump; and wherein the connection line connects to the feed line before the shut-off valve in the feed line.

Description

(1) The invention will be explained in more detail below with reference to an exemplary embodiment in conjunction with a drawing, in which:

(2) FIG. 1 shows a schematic illustration of a first embodiment according to the invention,

(3) FIG. 2 shows an enlarged illustration of FIG. 1,

(4) FIG. 3 shows a schematic illustration of a second embodiment according to the invention,

(5) FIG. 4 shows an enlarged illustration of FIG. 3,

(6) FIG. 5 shows a schematic illustration of a third embodiment according to the invention,

(7) FIG. 6 shows an enlarged illustration of FIG. 5,

(8) FIG. 7 shows a schematic illustration of a fourth embodiment according to the invention, and

(9) FIG. 8 shows an enlarged illustration of FIG. 7.

(10) FIG. 1 shows a first embodiment according to the invention of the tunnel boring device 10 according to the invention. A shaft 40 is schematically illustrated in FIG. 1. Also illustrated are surface installations 30 and the already created bore and the tunnel constructed therein or the pipeline 50 introduced therein.

(11) The tunnel boring device 10 comprises a schematically illustrated cutting disk 11 as boring tool. Provided behind the cutting disk 11 is a section 12 in which the cuttings (not shown) released by the cutting disk 11 collect. The region of the cutting disk 11 and of the section 12 is filled with a boring fluid (not shown), here in the form of a bentonite mud, for example.

(12) The region of the cutting disk 11 at the heading face (not shown) and the section 12 are connected to a feed line 13. The boring fluid is supplied to the region of the cutting disk 11 and to the section 12 by the feed line 13. Furthermore, the section 12 is connected to a suction line 14. The suction line 14 is connected to a suction connection 16 of a jet pump 15. A shut-off valve 17 is provided in the suction line 14. A conveying line 19 is provided on the delivery connection 18 of the jet pump 15. Furthermore, the jet pump 15 has a driving line connection 21 for a driving line 20.

(13) The feed line 13 extends from the surface installations 30 or from the shaft 40 through the already introduced pipeline or the already created tunnel 50. A feed pump 22 is provided in the feed line 13. This pump can be provided in the region of the surface installations 30 or in the shaft 40. A driving pump 23, which is configured as a high-pressure pump, is connected to the driving line 20. The conveying line 19 is connected to a separation unit 31 for separating the boring fluid from the cuttings. The feed pump 22 and the driving pump 23 are supplied with boring fluid from the separation unit 31 and then once again deliver said fluid to the cutting disk 11 or to the jet pump 15 via the feed line 13 or driving line 20.

(14) In operation, the region of the cutting disk 11 at the heading face and the section 12 are supplied with boring fluid by the feed pump 22 by the feed line 13. The jet pump 15 is likewise supplied with boring fluid by the driving pump 23 by the driving line 20. The driving fluid enters the jet pump 15 through the driving line connection 21. The driving fluid then passes to the driving nozzle 24 and through it, being accelerated in so doing, into the mixing chamber 25. The boring fluid, which fills the mixing chamber 25, is transported into a mixing pipe 26 as a result of the acceleration in the driving nozzle 24. Here, the thus accelerated boring fluid entrains the boring fluid located in the suction connection 16 and thus correspondingly also the boring fluid, which is located in the suction line 14, into the mixing chamber 25, with the result that the jet pump 15 then sucks in the boring fluid and the cuttings from the section 12 via the suction line 14. The boring fluid present as driving fluid together with the fluid from the suction line consisting of cuttings and boring fluid is then mixed in the mixing chamber 25 and transported into the conveying line 19 via the mixing pipe 26.

(15) To start the boring device, the shut-off valve 17 in the suction line 14 is first closed. The boring fluid in the driving line 20 is then supplied to the jet pump 15 via the driving pump 23. The acceleration which the boring fluid experiences in the driving nozzle 24 causes the boring fluid to be transported into the conveying line and through it to the separation unit 31. In the region of the suction connection 16 there is formed a negative pressure once the operation of the pump has properly adjusted itself. This negative pressure has the effect that, if the shut-off valve 17 is opened, the boring mud located in the suction line 14 is sucked directly into the pump 15. The cuttings released during the advance of the tunnel boring device 10 are then transported into the section 12 and mixed therein with the boring fluid. The mixture of cuttings and boring fluid is correspondingly sucked in by the jet pump 15 through the suction line 14.

(16) To start the boring device, the shut-off valve 17 in the suction line 14 is also first closed. The feed pump 22 is started and the region of the cutting disk 11 is supplied with boring fluid until the desired pressure is present at the heading face. The boring fluid in the driving line 20 is then supplied to the jet pump 15 via the driving pump 23. The acceleration which the boring fluid experiences in the driving nozzle 24 causes the boring fluid to be transported into the conveying line and through it to the separation unit 31. In the region of the suction connection 16 there is formed a negative pressure once the operation of the pump has properly adjusted itself. This negative pressure has the effect that, if the shut-off valve 17 is opened, the boring mud located in the suction line 14 is sucked directly into the pump 15. After opening the shut-off valve 17, the pressure at the heading face is readjusted by regulating the feed pump, if required. The cuttings released during the advance of the tunnel boring device 10 are then transported into the section 12 and mixed therein with the boring fluid. The mixture of cuttings and boring fluid is correspondingly sucked in by the jet pump 15 through the suction line 14. Here, the density and the friction losses in the conveying line 19 increase. At the same time, the suction power of the jet pump 15 drops if the pressure at the nozzle remains the same. For this reason, either the pressure and thus the volumetric flow at the driving nozzle 24 must be increased by means of the driving pump 23, which requires a direct regulation, in order to keep the heading face pressure constant, or the pressure provided by the driving pump 23 is set to be higher than the pressure loss which occurs, with the result that the pressure loss is compensated for, with the result that no relevant change in the heading face pressure occurs. If a change in the advance occurs, the density of the mixture of boring fluid and cuttings also changes. It has been shown that this change in density has no influence on the heading face pressure, and does not necessitate any adaption of the delivery volumetric flow, of the delivery pressure, of the feed volumetric flow or of the feed pressure. Here, the delivery parameters can occur for example at maximum in the delivery characteristic of the delivery pump, which is associated with energy losses during pumping, or the delivery parameters are set below the maximum but above the normally necessary delivery parameters (pressure and volumetric flow), with the result that a corresponding leeway is present. If a limit value is then exceeded, a corresponding regulation is required.

(17) After completion of the boring advance, the jet pump 15 is further operated until such time as cuttings no longer arise in the separation unit 31. The shut-off valve 17 is then closed, the delivery of the feed pump 22 is discontinued, and the delivery of the driving pump 23 is subsequently then discontinued, with the result that the delivery of the boring fluid through the conveying line 19 is then terminated.

(18) FIG. 3 and FIG. 4 show a second embodiment of a device according to the invention. This differs from the embodiment according to FIGS. 1, 2 in that the feed line 13 no longer extends to the shaft 40. Furthermore, no feed pump 22 is provided. Instead, there is provided only a driving pump 23 which is connected to the jet pump 15 by a driving line 20. A control valve 27, on which the feed line 13 taps, is provided in the driving line 20 in the region of the tunnel boring device 10. As before, the feed line 13 is connected to the region of the cutting disk 11 and the section 12.

(19) Upon starting, the boring fluid is supplied from the driving pump 23 to the jet pump 15 via the driving line 20 to the driving line connection 21. Here, the control valve 27 and the shut-off valve 17 are closed, with the result that the boring fluid, which has been delivered by the driving pump 23 to the jet pump 15, is supplied to the separation unit 31 again through the conveying line 19. First, the control valve 27 is opened to such an extent as to make available the required volumetric flow of boring fluid which is required in the region of the cutting disk, for example to provide the desired heading face pressure, and is to be supplied to the section 12. At the same time, the shut-off valve 17 is then opened, with the result that, as described above, the delivery of boring fluid and cuttings occurs through the suction line 14. Here, an adaptation of the feed volumetric flow must occur via a setting/adjustment of the control valve 27.

(20) Upon completion of the tunnel boring advance, the region of the cutting disk 11 and of the section 12 is further supplied with boring fluid until such time as no further cuttings arise in a separation unit 31. The control valve 27 and the shut-off valve 17 are then closed, and the delivery of the boring fluid by the driving pump 23 is discontinued.

(21) FIGS. 5, 6 show an alternative configuration of the embodiment of FIGS. 1, 2. Here, a shut-off valve 28 is provided in the feed line 13 in the region of the section 12. The shut-off valve 17 is arranged analogously thereto. A connection line 32 which has a shut-off valve 33 is provided between the feed line 13 and the suction line 14 in a section 29 between the shut-off valve 17 and suction connection 16. To start and prepare the boring, the shut-off valves 17 and 28 are closed. The shut-off valve 33 in the connection line is open. The driving pump 23 and the feed pump 22 are switched on and the boring fluid is transported through the feed line 13 and the connection line 32 to the suction connection 16 of the jet pump 15. The boring fluid supplied by the driving line 20 and the boring fluid supplied by the feed line 13 combine in the mixing chamber 25 and are conveyed away via the conveying line 19. As soon as the system has properly adjusted itself, the two shut-off valves 17 and 28 are opened and the shut-off valve 33 in the connection line 32 is closed, with the result that the jet pump 15 now sucks in from the section 12 through the suction line 14, with the region of the heading face or of the cutting disk 11 and of the section 12 being correspondingly supplied with boring fluid via the feed line 13.

(22) The feed pump 22 charges the extraction region and the heading face until a corresponding heading face pressure prevails. Where appropriate, a readjustment via the feed pump 22 is required. The jet pump 15 now sucks in from the section 12 through the suction line 14, with the removed boring fluid being correspondingly supplied again to the region of the heading face or of the cutting disk 11 and of the section 12 via the feed line 13. The boring operation and the keeping-constant of the heading face pressure occurs as described above.

(23) After completion of the boring operation, it is once more the case that, after no cuttings arise at the separation unit 31, the shut-off valves 17, 28, 33 are switched again in reverse order.

(24) FIGS. 7, 8 show an alternative embodiment of FIGS. 3, 4. Here, too, there is analogously provided a corresponding connection line 32 with shut-off valve 33. Furthermore, the feed line 13 likewise has a shut-off valve 28. With the shut-off valve 33 open and the control valve 27 correspondingly adjusted, the driving pump 23 is switched on, with the result that the necessary driving volumetric flow reaches the jet pump 15 at the driving line connection 21 via the driving line 20. At the same time, the feed volumetric flow set via the control valve 27 correspondingly flows through the connection line 22 to the suction connection 16 of the jet pump 15. If the system has properly adjusted itself, the shut-off valves 17, 28 are opened and the shut-off valve 33 of the connection line 32 is closed. As a result, the feed volumetric flow of the boring fluid is transported to the cutting disk 11 or section 12 and at the same time conveyed from the section 12, while being correspondingly mixed with cuttings, via the suction line 14 to the suction connection 16 of the jet pump 15. The boring fluid together with the cuttings enters the mixing chamber 25 of the jet pump 15, is mixed there with the volumetric flow from the driving line 20 and supplied to the separation unit 31 via the mixing pipe 26 and the conveying line 19. The termination of the boring operation brings about a reverse switching order of the shut-off valves 17, 28, 33. Here, the heading face pressure is correspondingly kept constant as described above.

(25) The jet pump as delivery pump makes it possible in a surprising manner for density fluctuations caused by the reception/suction/removal of cuttings with the boring fluid to be compensated for within the characteristic values, with the result that the heading face pressure remains substantially constant in spite of changes in the advancing rate or in the density of the cuttings.

(26) The connection line 32 and the provision of the shut-off valves 17, 28, 33 bring about a decisive improvement during the starting of the tunnel boring device 10 to the effect that the jet pump 15 is already completely in a regulated operation and no vacuum is present at the suction connection 16. If the shut-off valves 17, 28, 33 are now switched, there immediately begins the direct transport of the boring fluid into and out of the section 12. Since the section 12 is already correspondingly filled with boring fluid, a release of the vacuum which prevails at the shut-off valve 17 if no connection line 32 is provided is thereby avoided. The release of the vacuum by actuating the shut-off valve 17 produces a sudden pressure increase in the region of the heading face, which can be correspondingly avoided by the provision of the connection line 32.

LIST OF REFERENCE SIGNS

(27) 10 tunnel boring device

(28) 11 cutting disk/boring tool

(29) 12 section

(30) 13 feed line

(31) 14 suction line

(32) 15 jet pump

(33) 16 suction connection

(34) 17 shut-off valve

(35) 18 delivery connection

(36) 19 conveying line

(37) 20 driving line

(38) 21 driving connection

(39) 22 feed pump

(40) 23 driving pump/high-pressure pump

(41) 24 driving nozzle

(42) 25 mixing chamber

(43) 26 mixing pipe

(44) 27 control valve

(45) 28 shut-off valve

(46) 29 section

(47) 30 surface installations

(48) 31 separation unit

(49) 32 connection line

(50) 33 shut-off valve

(51) 40 shaft

(52) 50 pipeline/tunnel