UNDERGROUND DRILLING RIG AND METHOD FOR ERECTING SAME

20220307373 · 2022-09-29

    Inventors

    Cpc classification

    International classification

    Abstract

    The Invention relates to an underground drilling rig (10) and a method for its erection, wherein the method, in a special embodiment, comprises erecting a mast structure (20) of the drilling rig (10) extending from a horizontal tunnel (production tunnel) into a vertical mast shaft (14) and by means of an erecting structure (50), wherein the mast structure (20) comprises a plurality of mast segments (60) connected to one another or connectable to one another.

    Claims

    1. (canceled)

    2. A method for erecting a drilling rig (10) for sinking boreholes on hydrocarbon deposits or for developing geothermal energy or other valuable materials or for research purposes, in a tunnel driven into a rock mass, which comprises a horizontal section functioning as a production tunnel (12) and production line, from which a vertical section extends as a mast shaft (14), characterized by the following method steps: erecting a mast structure (20) in the mast shaft (14) by means of an erecting structure (50) in the production tunnel (12), wherein the mast structure (20) comprises a plurality of mast segments (60) connected to one another or connectable to one another.

    3. The method according to claim 2, wherein successive mast segments (60) are fed to the erecting structure (50) on an input side of the erecting structure (50) in a horizontal or at least substantially horizontal orientation, wherein by means of the erecting structure (50) in each case at least one mast segment (60) on the output side of the erecting structure (50) is erected in a vertical or at least substantially vertical orientation into the mast shaft (14) or at least pointing into the mast shaft (14) and wherein while feeding further mast segments (60) on the input side of the erecting structure (50) the or each mast segment (60) already vertically erected on the output side of the erecting structure (50) is raised into the mast shaft (14).

    4. The method according to claim 3, wherein the erecting structure (50) comprises two erecting trestles (52) arranged at a distance from one another and parallel to one another and wherein each erecting trestle (52) carries a guide profile (54) for mast segments (60), wherein a first section (56) of the guide profile (54) is oriented horizontally or at least substantially horizontally at a first end of the erecting trestles (52), wherein a second section (58) of the guide profile (54) is oriented vertically or at least substantially vertically at a second end of the erecting trestles (52) opposite the first end, wherein the vertical or at least substantially vertical sections (58) of the guide profiles (54) below the mast shaft (14) point into the mast shaft (14), wherein in each case a mast segment (60) of the erecting structure (50) is transferred in the area of the first section (56) of the guide profiles (54) there and guided in the guide profiles (54) and wherein the transferred mast segment (60) is moved along the guide profiles (54) and is erected in the area of the second sections (58) of the guide profiles (54) there by means of the second sections (58) of the guide profiles (54).

    5. The method according to claim 4, wherein the mast segments (60) are connected to one another in an articulated manner.

    6. The method according to claim 2, wherein the erection of the mast structure (20) in the mast shaft (14) occurs by means of the erecting structure (50), by in each case at least one mast segment (60) in the erecting structure (50) being pulled or pushed in the horizontal or at least substantially horizontal direction and/or raised in the vertical or at least substantially vertical direction.

    7. The method according to claim 2, wherein a crown bearing (22) is raised in the mast shaft (14) by means of the mast structure (20).

    8. The method according to claim 2, wherein the crown bearing (22) is raised by means of a lifting device in the mast shaft (14).

    9. The method according to claim 7, wherein the crown bearing (22) is fixed in the mast shaft (14) transversely to a vertical axis of the mast shaft (14) in the mast shaft (14), and wherein this fixation takes place by means of at least one strut (26) functioning as a crown bearing fixing strut, which extends from the crown bearing (22) to the wall of the mast shaft (14).

    10. An apparatus for erecting a drilling rig (10) for sinking boreholes on hydrocarbon deposits or for developing geothermal energy or other valuable materials or for research purposes, in a tunnel driven into a rock mass, which comprises a horizontal section functioning as a production tunnel (12) and production line, from which a vertical section extends as a mast shaft (14), wherein the apparatus functions as erecting structure (50) for a mast structure (20) of the drilling rig (10), wherein the mast structure (20) comprises a plurality of mast segments (60) connected to one another or connectable to one another, wherein at least one mast segment (60) can be fed to the erecting structure (50) on an input side in a horizontal orientation, wherein a mast segment (60) fed to the erecting structure (50) on its input side can be guided through the erecting structure (50) or along the erecting structure (50) up to an output side of the erecting structure (50) and wherein the mast segment (60) can be erected in the area of the output side and is brought into a vertical orientation.

    11. The apparatus according to claim 10, wherein a mast segment (60) guided through the erecting structure (50) or along the erecting structure (50) pushes in front of it each mast segment (60) previously fed to the erecting structure (50) through the erecting structure (50) or along the erecting structure (50).

    12. The apparatus according to claim 11, wherein by means of a mast segment (60) erected by means of the erecting structure (50) each mast segment (60) already erected by the erecting structure (50) can be raised into the mast shaft (14).

    13. The apparatus according to claim 12, wherein the erecting structure (50) comprises two erecting trestles (52) arranged at a distance from one another and parallel to one another and wherein each erecting trestle (52) carries a guide profile (54), wherein a first section (56) of the guide profile (54) is oriented horizontally or at least substantially horizontally at a first end of the erecting trestles (52), wherein a second section (58) of the guide profile (54) is oriented vertically or at least substantially vertically at a second end of the erecting trestles (52) opposite the first end, wherein the vertical or at least substantially vertical sections (58) of the guide profiles (54) below the mast shaft (14) point into the mast shaft (14).

    14. A mast structure (20) of a drilling rig (10) for sinking boreholes on hydrocarbon deposits and for developing geothermal energy or other valuable materials or for research purposes, in a tunnel driven into a rock mass, which comprises a horizontal section functioning as a production tunnel (12) and production line, from which a vertical section extends as mast shaft (14), wherein the mast structure (20) is erected by means of a method according to claim 2.

    15. A drilling rig (10) for sinking boreholes on hydrocarbon deposits and for developing geothermal energy or other valuable materials or for research purposes, in a tunnel driven into a rock mass, which comprises a horizontal section functioning as a production tunnel (12) and production line, from which a vertical section extends as a mast shaft (14), and having a mast structure (20) according to claim 14.

    16. (canceled)

    17. The method according to claim 8, wherein the crown bearing (22) is fixed in the mast shaft (14) transversely to a vertical axis of the mast shaft (14) in the mast shaft (14), and wherein this fixation takes place by means of at least one strut (26) functioning as a crown bearing fixing strut, which extends from the crown bearing (22) to the wall of the mast shaft (14).

    18. A mast structure (20) of a drilling rig (10) for sinking boreholes on hydrocarbon deposits and for developing geothermal energy or other valuable materials or for research purposes, in a tunnel driven into a rock mass, which comprises a horizontal section functioning as a production tunnel (12) and production line, from which a vertical section extends as mast shaft (14), wherein the mast structure (20) is erected by means of an apparatus according to claim 10.

    19. A drilling rig (10) for sinking boreholes on hydrocarbon deposits and for developing geothermal energy or other valuable materials or for research purposes, in a tunnel driven into a rock mass, which comprises a horizontal section functioning as a production tunnel (12) and production line, from which a vertical section extends as a mast shaft (14), and having a mast structure (20) according to claim 18.

    Description

    BRIEF DESCRIPTION OF THE DRAWINGS

    [0049] FIG. 1 shows, in a highly schematically simplified form, different variants of a design of a drilling rig underground (underground drilling rig);

    [0050] FIG. 2 shows a tunnel in a rock mass with a horizontal section (production tunnel) and a vertical shaft extending therefrom (mast shaft), wherein the erection of the underground drilling system takes place in the production tunnel and at least partially into the mast shaft;

    [0051] FIG. 3 and FIG. 4 show different views/partial views of an underground drilling rig erected in the production tunnel with a mast structure extending into the mast shaft;

    [0052] FIG. 5 shows snapshots during the installation of an erecting structure intended for erecting the mast structure in the mast shaft;

    [0053] FIG. 6 shows snapshots when erecting the mast structure into the mast shaft by means of the erecting structure; and

    [0054] FIG. 7 shows an enlarged illustration of an upper mast segment of the mast structure.

    DETAIL DESCRIPTION OF ILLUSTRATED EMBODIMENTS

    [0055] The illustration in FIG. 1 (FIG. 1A, FIG. 1B, FIG. 1C) shows in a greatly simplified schematic form a drilling rig 10 underground (underground drilling rig 10). The drilling rig 10 is erected underground in a horizontal tunnel, referred to here and below as production tunnel 12, from which a vertical shaft, referred to below as mast shaft 14, extends. From the mast shaft 14, in an in principle optional manner, at least one ventilation shaft 16 extends up to the surface above ground.

    [0056] In the production tunnel 12, which has a circular or at least substantially circular cross-sectional contour, a floor level 18 of the production tunnel 12 is formed, for example, at least in the area that is intended for the erection of the drilling rig 10, in order to obtain a level or at least substantially level installation surface by heaping up excavated material and/or by attaching a standing surface, which functions as a floor level 18, which, if necessary, rests on heaped up excavated material.

    [0057] In the schematically greatly simplified illustration of the drilling rig 10, a mast structure 20 (FIG. 1A) and a crown bearing 22 (FIG. 1B, FIG. 1C) are shown. At the upper end of the mast structure 20 a crown bearing 22 connected to the mast structure 20 can be located, or above the mast structure 20 a crown bearing 22 can be located that is independent of the mast structure 20 or that is connected to the mast structure 20, as shown in FIGS. 1B, 1C.

    [0058] The illustrations in FIG. 1A, FIG. 1B and FIG. 1C illustrate by means of the respective arrows the dissipation of the forces acting during the drilling operation, in particular due to the weight of the drill string 24 (or so-called casing pipes). In the situation in FIG. 1A, the forces are directed into the ground due to the mast structure 20 standing directly or indirectly on the floor level 18 of the production tunnel 12. In the situation in FIG. 1B and FIG. 1C, the crown bearing 22 is to a certain extent suspended in the mast shaft 14 at a distance from the production tunnel 12. In the situation in FIG. 1B, the crown bearing 22 is fixed in the mast shaft 14 along its vertical axis and transversely to its vertical axis by means of struts 26 extending from the crown bearing 22 and reaching the wall of the mast shaft 14 (mast shaft wall). In the situation in FIG. 10, the crown bearing 22 (in a configuration connected to a mast structure 20 or individually and without a connection to a mast structure 20) is fixed in the mast shaft 14 at least along its vertical axis by means of a suspension 28 extending from the surface above ground, through the ventilation shaft 16 and to the crown bearing 22. An additional fixation transversely to its vertical axis can be provided according to FIG. 1B.

    [0059] FIG. 2 shows an isometric illustration of a section of the production tunnel 12 and the mast shaft 14 extending from the production tunnel 12 in the vertical direction.

    [0060] The illustrations in FIG. 3 (FIG. 3A, FIG. 3B) show—from different viewing directions—a drilling rig 10 erected in a production tunnel 12 and into a mast shaft 14 extending therefrom. The illustration in FIG. 4 shows this drilling rig 10 in the area of the production tunnel 12 and of a section of the mast shaft 14 directly adjoining the production tunnel 12 in a view when looking along the longitudinal axis of the production tunnel 12.

    [0061] The illustrations in FIG. 3 and in FIG. 4 show the drilling rig 10 with further details compared to the illustrations in FIG. 1. Accordingly, the drilling rig 10 comprises, in addition to the mast structure 20 and the crown bearing 22, a substructure 30 with the so-called drill floor 32 as the upper end of the substructure 30. In the embodiment shown, the mast structure 20 of the drilling rig 10 is a “two-legged” mast structure 20. On the drill floor 32, a plurality of drill pipe elements 34 are placed next to the mast structure 20. These are held in a manner which is in principle known per se by means of at least one holding structure extending from the mast structure 20, in particular a holding structure in the form of or in the manner of a so-called finger board 36. Drill pipe elements 34 are placed there next to the mast structure 20 in a manner which is in principle known per se. When installing the drill string 24, drill pipe elements 34 are accommodated there in a manner which is in principle known per se and connected to the drill string 24. In the embodiment shown, the drill pipe elements 24 placed next to the mast structure 20 are each drill pipe elements 24 (quintuple stands) combined from five individual drill pipes. Drill pipe elements 24 with more or less than five individual drill pipes are also conceivable and usable, especially in a drilling rig 10 with a correspondingly adapted height of the mast structure 20 and/or a correspondingly adapted vertical position of at least one holding structure extending from the mast structure 20.

    [0062] The movement of drill pipe elements 34 from and to the position above the borehole underground and from and to the position next to the mast structure 20 takes place in the drilling rig 10 shown by way of example by means of a drill string drive unit, in particular a so-called top drive 38 that functions as a drill string drive unit and is in principle known per se. The drill string drive unit, the top drive 38 in the situation shown, can be moved vertically along the mast structure 20 in a manner which is in principle known per se. By means of the drill string drive unit, the drill string 24 is rotated during the drilling operation in a manner which is in principle known per se. The vertical movement of the drill string drive unit takes place in a manner which is in principle known per se by means of a hoisting apparatus 40 (FIG. 4) and a pulley system in principle known per se, comprising the crown bearing 22 as the upper block.

    [0063] In order to feed drill pipe elements 34 to the drill floor 32, a machine, which is in principle known per se, is arranged for this purpose in the production tunnel 12 and in alignment with the longitudinal axis of the production tunnel 12. As an example of such a machine, a so-called catwalk machine 42 is shown in the illustrations in FIG. 3A and FIG. 3B.

    [0064] Below the drilling rig 10, a so-called blow-out preventer 44 (BOP) is located above the borehole in a manner which is in principle known per se. To accommodate it, the production tunnel 12 is extended (deepened) in a cellar-like manner below the drilling rig 10 and in the region of the borehole. Similar to the way in which a section extending from the production tunnel 12 and extending beyond the edge contour of the production tunnel is provided for the blow-out preventer 44—as the illustration shows this in FIG. 4—a side room optionally extending from the production tunnel 12 is provided for the hoisting apparatus 40. The arrangement of the hoisting apparatus 40 shown here is only an example and can also assume alternative positions.

    [0065] The illustrations in FIG. 5 (FIG. 5A, FIG. 5B, FIG. 5C, FIG. 5D) show a section of the production tunnel 12 and a section of the mast shaft 14 extending therefrom, as well as a mast structure erecting structure intended for erecting the mast structure 20 in the mast shaft 14 and referred to here and below in short as an erecting structure (erecting unit) 50. The representations in FIG. 5 likewise illustrate a method for erecting this erecting structure 50, which can also be referred to as an erecting apparatus.

    [0066] In the embodiment shown, the erecting structure 50 comprises two erecting trestles 52 aligned side by side and parallel to one another (see FIG. 5D). Each erecting trestle 52 comprises a guide for segments of the mast structure 20 to be erected by means of the erecting trestles 52 and guide profiles 54 as a guide.

    [0067] The guide and the guide profiles 54 there are divided into at least three adjoining sections and function as a continuous guide. In respect to the illustrations in FIG. 5C and FIG. 5D and the direction of view there on the erecting trestle 52 or the erecting trestles 52, these are—when viewed from approximately bottom left to approximately top right—a horizontal section 56, preferably a horizontal section 56 that is aligned with a longitudinal axis of the production tunnel 12, an adjoining arc-shaped section and, in turn, a vertical section 58 adjoining it. The vertical section 58 extends into the mast shaft 14 and with its total height beyond the ceiling of the production shaft 12. The vertical section 58 is therefore erected into the mast shaft 14. This is shown by the illustrations in FIG. 5A and FIG. 5B.

    [0068] The illustration in FIG. 5A shows, in a snapshot, an erecting trestle 52 with an initially still lowered (horizontally oriented) vertical section 58. The erecting trestle 52 is located under the mast shaft 14 only with a part of the vertical section 58 to be erected. The illustration in FIG. 5B shows, in a snapshot, the erecting trestle 52 from FIG. 5A with a partially erected vertical section 58. The erecting takes place, for example, by means of a hydraulic cylinder or the like engaging with the erecting frame 52, on the one hand, and with a boom extending from the vertical section 58, on the other hand, or by means of a separate lifting device. When erecting the vertical section 58 and together with the erection, the erection trestle 52 is moved further under the mast shaft 14 (when comparing the illustrations in FIG. 5A and FIG. 5B, it can be seen, that the erecting trestle has been moved “to the right”, therefore further under the mast shaft 14).

    [0069] The illustration in FIG. 5C shows, in a snapshot, the erecting trestle 52 from FIG. 5B with an erected vertical section 58. The vertical section 58 adjoins the arc-shaped section of the guide and the result is a continuous guide with an input-side horizontal section 56, an adjoining arc-shaped section and, in turn, an adjoining output-side vertical section 58.

    [0070] At the end of the erection of the vertical section 58, the erection trestle 52 is also moved further under the mast shaft 14. In the situation shown in FIG. 5C, it can be seen that the erecting trestle 52 has already been partially moved beyond the area with the mast shaft 14. The vertical section 58 protrudes into the mast shaft 14 and a longitudinal axis of the vertical section 58 is aligned with a vertical axis of the mast shaft 14. When comparing the illustrations in FIG. 5B and FIG. 5C, it can be seen that the erecting trestle 52 has been moved “further to the right”, therefore even further under the mast shaft 14 and partly beyond the area with the mast shaft 14.

    [0071] The illustration in FIG. 5D shows two erecting trestles 52 placed next to one another, each with erected vertical sections 58 as in FIG. 5C. The illustration in FIG. 5D also shows an in principle optional extension of the horizontal sections 56 in front of the erecting trestles 52 and aligned with a longitudinal axis of the production tunnel 12. The illustration in FIG. 5D (but also other illustrations) furthermore shows in an area above the horizontal sections 56 an optional crane system in front of the erecting trestles 52. This is attached, for example, to the ceiling of the production tunnel 12. By means of such or a similar crane system, mast segments 60 delivered, for example, in the production tunnel 12 by means of a vehicle traveling there or the like can be placed on the horizontal sections 56 in front of the erecting trestles 52. Such a or a similar crane system can optionally also or alternatively also be used in other ways, for example, for lowering the BOP 44 into the area of the production tunnel 12, which is deepened in the manner of a cellar.

    [0072] The denomination of the individual sections 56, 58 of the guide as input side and output side relates to a direction of a movement of segments of the mast structure 20 when the mast structure 20 is erected along the guide and thus overall in the erecting structure 50. The erection of the mast structure is shown in FIG. 6.

    [0073] The illustrations in FIG. 6 (FIG. 6A, FIG. 6B, FIG. 6C, etc.) show snapshots during the erection of the mast structure 20 of a drilling rig 10 according to FIG. 3 and FIG. 4. The mast structure 20 is a “two-legged” mast structure 20 and is formed from individual mast segments 60 connected to one another or connectable to one another. The “two-legged” mast structure 20 is selected here only as an example and can also have other embodiments, in particular, a multi-legged mast structure 20 with three or more legs is possible, in which two adjacent legs form a contact surface for placement in the erecting structure 50.

    [0074] The illustration in FIG. 6A shows a snapshot with a first mast segment 60 placed in the erecting structure 50. The mast segment 60 is placed in the area of the horizontal section 56 of the guide profiles 54 of the erecting trestles 52 (input side of the erecting structure 50), here even by way of example in the area of the extension in front of the horizontal sections 56 on the guide profiles 54 there.

    [0075] In the example shown, the mast segment 60 placed on the guide profiles 54 comprises the crown bearing 22. This mast segment 60 is later the top segment of the mast structure 20 in the erected mast structure 20, so that the crown bearing 22 is raised together with the erection of the mast structure 20. The mast structure 20 is thereby erected into the mast shaft 14 and with this erection the crown bearing 22 is also raised into the mast shaft 14. Thus, after the mast structure 20 has been erected, the crown bearing 22 is located at the top of the mast structure 20, therefore, in the area of the highest point of the mast structure 20.

    [0076] It should be pointed out that a crown bearing 22 connected to a mast segment 60 is only an option and that for erecting the mast structure 20 it does not depend on whether a crown bearing 22 is connected to one of the mast segments 60. For the further description of the erection of the mast structure 20, the crown bearing 22 is therefore no longer taken into account. A crown bearing 22 connected to a mast segment 60, in particular, a crown bearing 22 connected to the first mast segment 60 placed on the erecting structure 50, and a crown bearing 22 raised with the erection of the mast structure 20 are nevertheless always to be read in the further description.

    [0077] The illustration in FIG. 6B shows a snapshot with a mast segment 60 moved further along the erecting structure 50 and the guide profiles 54 of the erecting trestles 52 compared to the situation in FIG. 6A, namely a mast segment 60 moved further in the direction of the arc-shaped sections adjoining the horizontal sections 56. This movement takes place automatically or semi-automatically by means of a drive device not shown in the illustrations. Such a drive device engages—as described above—for example, pulling or pushing, with the mast segment 60 and causes the movement along the guide profiles 54 of the erecting trestles 52 and thus overall along the erecting structure 50. Apparatuses coming into consideration as a drive device have been exemplarily mentioned above.

    [0078] The illustration in FIG. 6C shows the erecting structure 50 and its erecting trestles 52 as in FIG. 6A and FIG. 6B, wherein two further mast segments 60 are now placed on the guide profiles 54 of the erecting trestles 52 (and here partly also on the guide profiles 54 of the extension in front of the erecting trestles 52). The drive device mentioned before in the description of the illustration in FIG. 6B engages with one of these new mast segments 60, in particular, with the last new mast segment 60 and causes its movement along the guide profiles 54 in the direction of the vertical sections 58. The mast segment 60 moved in each case with the drive device pushes each mast segment 60 located in the direction of movement in front of said mast segment 60 in front of it. In the snapshot shown in FIG. 6C, this has the effect that the mast segment 60, which was first placed in the erecting structure 50, was moved into the area of the vertical sections 58 (output side of the erecting structure 50) and there has been erected from the originally horizontal orientation to a vertical orientation.

    [0079] It should be pointed out that the illustration in FIG. 6C is a snapshot of the erection of the mast structure 20 and that the number of exactly two further mast segments 60 shown there in comparison to the situation in FIG. 6B does not constitute a determining factor for the method for erecting the mast structure 20. It is therefore not necessary that exactly two new mast segments 60 are always fed to the erecting structure 50. The number of new mast segments 60 can be larger or smaller. Which new mast segment 60 or which new mast segments 60 in the case of a plurality of new mast segments 60 is or are moved by means of the drive device along the erecting structure 50 depends on the position of the drive device relative to the erecting structure 50 and, for example, also depends on whether the mast segments 60 or at least the new mast segments 60 are connected to one another, for example—as shown—are connected to one another in an articulated manner.

    [0080] The drive device, which engages with in each case a mast segment 60 placed in the area of the input side of the erecting structure 50, preferably works in a clocked manner and thereby moves back and forth, for example, in the area of the input side, therefore, in the area of the horizontal sections 56, in each case alternately over a predetermined distance, in particular a distance, whose length is at least slightly greater than the length of a mast segment 60. Each mast segment 60 that comes into the effective area of the drive device by being placed in the erecting structure 50 is detected by the drive device, for example, by a driver moved by the drive device, and then moved in the direction of the vertical sections 58.

    [0081] The illustration in FIG. 6D shows a further snapshot when erecting the mast structure 20 in the mast shaft 14. Now, by means of the vertical sections 58 of the guide profiles 54 of the erecting trestles 52, another mast segment 60 is erected and brought into a vertical orientation aligned with the vertical axis of the mast shaft 14. On the first, previously erected mast segment 60, struts 26 extending from the mast segment 60 can be seen, which support the mast segment 60 and thus the mast structure 20 as a whole against the mast shaft 14. These struts 26 have the effect that the mast structure 20 remains upright when the mast structure 20 is further erected in the mast shaft 14 and does not incline against the side wall of the mast shaft 14. In the case of a “two-legged” mast structure 20—as shown—there is a risk of an undesired inclination of the mast structure 20 against the side wall of the mast shaft 14 only transversely to the plane defined by the mast structure 20. With such a configuration, two struts 26 (or in each case two struts 26 at the same height as the mast structure 20) are sufficient to support the mast structure 20 in the mast shaft 14, and these struts 26 are each oriented transversely to the plane defined by the mast structure 20. There is no need for a restriction to precisely two struts 26 and more than two struts 26, for example, two or more struts 26 on each side of the mast structure 20, are also conceivable. Supporting the mast structure 20 by means of precisely two struts 26 is therefore only one of several possible options. The struts 26 support the mast structure 20 during its erection and/or during the later drilling operation. During the later drilling operation, the mast structure 20 can additionally or alternatively be supported in the mast shaft 14 by means of bracing the mast structure 20 in the mast shaft 14 with steel cables or the like or by means of further struts (not shown) along the mast structure 20. In the case of such further struts along the mast structure 20, in each case a group of struts (two or more struts extending from the mast structure 20 and reaching as far as the mast shaft wall) comes into consideration, for example, in different vertical positions. Such a group of struts can extend from each mast segment 60 of the mast structure 20 or from every second or every third or every fourth mast segment 60 of the mast structure 20. As an alternative to such a group formation, it is also possible, for example, for individual mast segments 60, in particular successive mast segments 60, in each case to have struts pointing in different radial directions along the mast structure.

    [0082] In the illustration in FIG. 6D, the struts 26 are shown as rigid struts 26 extending radially from a vertical axis of the mast structure 20 and reaching to a section of the side wall of the mast shaft 14, at the free ends of which intended for contact with the mast shaft 14 in each case a roller or the like is located. Rigid struts 26 (in the area of the crown bearing 22 and/or along the entire mast structure 20) with rollers or the like at their ends come into consideration for a cylindrical or at least substantially cylindrical mast shaft 14, in any event for a mast shaft 14, the geometry of which and the dimensions of which are known and do not change significantly along its vertical axis. The length of each strut 26 is then matched to the respective distance from the starting point of the strut 26 on the mast segment 60 to the mast shaft wall. The length is of course determined in the direction of the intended orientation of the strut 26 in each case. A roller or the like at the end of a strut 26 dimensioned in this way is preferably mounted resiliently or elastically in some other suitable manner for the purpose of tolerance compensation. It is also conceivable to dispense with the struts 26 (in the area of the crown bearing 22 and/or along the entire mast structure 20). For this purpose, the mast structure 20 is designed to be free-standing in the mast shaft 14. An underground drilling rig 10 with a free-standing mast structure 20 is to be regarded as encompassed by the description presented here and whenever a mast structure 20 erected in the mast shaft 14 is mentioned, a mast structure 20 supported by means of struts 26 or the like in the mast shaft 14 and/or one fixed by means of bracing or the like in the mast shaft 14 and/or one standing freely in the mast shaft must also be read.

    [0083] In a particular embodiment, the struts 26—struts 26 in the area of the crown bearing and/or struts 26 along the entire mast structure 20—are automatically telescopic along their longitudinal axis. The automatic telescoping takes place, for example, by means of a control, which processes a signal from an inclination sensor (not shown) on the mast structure 20, in particular, an inclination sensor on that mast segment 60, from which the respective strut 26 extends.

    [0084] An automatic telescoping is advantageous, when the surface of the mast shaft wall is assumed to be irregular. When such a strut 26 comes into contact with its free end with an inwardly bulging section of the mast shaft wall, the strut 26 with its current length presses the mast structure 20 to the side in a certain extent, so that it is inclined relative to the vertical. This inclination can be detected by means of the inclination sensor and a sensor signal encoding the resulting inclination can be used to automatically adjust the length of the strut 26. In the event of contact with an inwardly bulging section of the mast shaft wall, this control leads to a shortening of the length of the strut 26. The lateral pressure on the mast structure 20 due to the previously too long strut 26 for this section of the mast shaft 14 disappears.

    [0085] For an outwardly bulging section of the mast shaft wall or in connection with a section of the mast shaft wall that previously bulged inward, the same applies accordingly in reverse. If the strut 26 loses contact with the mast shaft wall with such a bulge and this leads to an inclination of the mast structure 20, this inclination can also be detected by means of the inclination sensor and a corresponding signal can also be used here to adjust the length of the strut 26. Here, this control leads to an increase in the length of the strut 26. As soon as the strut 26, which was previously too short for this section of the mast shaft 14, is again in contact with the mast shaft wall, the strut 26 takes on the support function for the mast structure 20 again.

    [0086] Optionally, such a control can also be superimposed with an automatic detection of a continuously existing contact of the free end of each strut 26 with the mast shaft wall. For this purpose, a roller mounted on the end of a strut 26, for example, resiliently, is connected to a sensor, for example, a sensing device, placed along the spring path. As long as the strut 26 with its roller is in contact with the mast shaft wall, the roller is slightly spring-deflected and the sensor delivers a signal, which encodes the contact of the roller with the mast shaft wall. As soon as the roller loses contact with the mast shaft wall, it springs outwards and the sensor signal disappears. When the sensor signal disappears, a telescoping of the strut 26 is automatically triggered to obtain a greater length of the strut 26 until the roller comes into contact with the mast shaft wall again and the sensor signal reappears.

    [0087] The illustrations in FIG. 6E, FIG. 6F and FIG. 6G show further snapshots during the erection of the mast structure 20 by means of the erecting structure 50 and into the mast shaft 14. The illustration in FIG. 6G shows a mast structure 20 with a height suitable for the drilling operation (a height adapted to the length of the drill pipe elements 34 provided for use during the drilling operation). This height is achieved in that when the mast structure 20 is erected by means of the erecting structure 50, in each case mast segments 60 are fed to said erecting structure on its input side, which push previously fed mast segments 60 in front of them in the erecting structure 50, so that originally horizontally fed mast segments 60 are erected by means of the erecting structure 50 in the area of its output side (are brought into an orientation aligned with the vertical axis of the mast shaft 14) and there leave the erecting structure 50 and erected mast segments 60 are raised into the mast shaft 14.

    [0088] In the illustration in FIG. 6G, a top drive 38 is also already shown in the mast structure 20. This hangs in a manner that is in principle known per se on the pulley system extending from the crown bearing 22 and is guided by the mast structure 20 (function of the mast structure 20 as a torque support and function of the mast structure 20 for guiding and centering the top drive 38 over the borehole). For this purpose, the mast structure 20 is designed, for example, with opposing and facing profiles, for example, U-profiles. Rollers and/or sliding shoes or the like extending from the top drive 38 run in such profiles. The top drive 38 can thus be moved vertically along the mast structure 20 and in the profiles there (in a manner which is in principle known per se).

    [0089] Specifically in the illustration in FIG. 6G (but also already in the illustrations in FIG. 3A, FIG. 3B, FIG. 6F), an upper end of the mast shaft 14 is shown as a disk. This disk constitutes—schematically simplified—a closure of the mast shaft 14 to the surface (a closure of the mast shaft to the area above ground). This disk is shown with an opening. This opening constitutes—also schematically simplified—a ventilation shaft 16 (not designated in the figures mentioned; see, for example, FIG. 1). With reference to the mast shaft 14 which is closed or at least substantially closed to the area above ground, it becomes clear that the erection proposed here of an underground drilling rig 10 or the respective components of the underground drilling rig 10 takes place extending from a horizontal tunnel functioning as a production tunnel 12 into the (vertical) mast shaft 14, therefore “from bottom to top”.

    [0090] The illustration in FIG. 7 shows in an enlargement the upper end of a mast structure 20 erected by means of the erecting structure 50 and according to the method as described above. A mast segment 60, here a mast segment 60 with the crown bearing 22, forms the upper end of the mast structure 20. Here a configuration with exactly three struts 26 is shown for supporting the mast structure 20 in the mast shaft 14 (during the drilling operation and previously when erecting the mast structure 20). One of these struts 26 is oriented on one side of the plane defined by the mast structure 20 transversely to said plane. Two struts 26 are located on the opposite side of the plane defined by the mast structure 20. These each enclose an angle with an imaginary plane, which is perpendicular to the plane defined by the mast structure 20 along the vertical axis of the mast structure 20. Both angles are the same or at least substantially the same and the distance measured from the starting point of the struts 26 from the mast segment 60 up to this plane is also the same or at least substantially the same for both struts 26. This results in a radial or at least substantially radial orientation of the struts 26 (this applies to the individual struts 26 as well as to the two struts 26) and with such a radial orientation a configuration comes into consideration with further struts 26, for example, on both sides in each case two struts 26, on both sides in each case three struts 26, one or two struts 26 on one side, three struts 26, etc. on the other side.

    [0091] Individual aspects of the description submitted here that are in the foreground can thus be briefly summarized as follows: The invention relates to an underground drilling rig 10 (drilling rig 10 for deep drilling underground) and a method for its erection. During the erection, in one embodiment of the method, a crown bearing 22 of the drilling rig 10 is raised into a vertical shaft (mast shaft 14) extending from the installation site (production tunnel 12) (raised extending from the production tunnel 12 into the mast shaft 14; therefore, “from bottom to top”). This raising takes place either alone, in that only the crown bearing 22 is raised in the mast shaft 14, or in that the crown bearing 22 is raised by means of the mast structure 20 when a mast structure 20 of the drilling rig is being erected. To erect the mast structure 20, in one embodiment of the method, an erecting structure 50 is provided, which takes into account the fact that the mast structure 20 cannot be brought erect to the erection site of the drilling rig 10 in the production tunnel 12 and rather has to be assembled only on site (underground). The mast structure 20 is erected extending from the production tunnel 12 into the vertical mast shaft 14, therefore, “from bottom to top”. In this respect, the invention also relates to this erection structure 50, a method for its operation, therefore a method for erecting a mast structure 20 of a drilling rig 10 into a vertical mast shaft 14 extending from the production tunnel 12 at the erection site of the drilling rig 10, and a mast structure 20 erected according to the method and a drilling rig 10 (underground drilling rig 10) with such a mast structure 20. The mast structure 20 can carry a crown bearing 22 and/or raise it. A drilling rig 10 with such a mast structure 20 and without a crown bearing 22 is also possible.

    LIST OF REFERENCE SIGNS

    [0092] 10 underground drilling rig, drilling rig [0093] 12 production tunnel [0094] 14 mast shaft [0095] 16 ventilation shaft [0096] 18 floor level (production tunnel) [0097] 20 mast structure [0098] 22 crown bearing [0099] 24 drill string [0100] 26 strut [0101] 28 suspension (in the mast shaft) [0102] 30 substructure [0103] 32 drill floor [0104] 34 drill pipe element [0105] 36 finger board [0106] 38 top drive [0107] 40 hoisting apparatus [0108] 42 catwalk-machine [0109] 44 blow-out-preventer [0110] 50 erecting structure [0111] 52 erecting trestle [0112] 54 guide profile [0113] 56 horizontal section (of the guide profile/the erecting trestle) [0114] 58 vertical section (of the guide profile/the erecting trestle) [0115] 60 mast segment