EP2527539B1 - Submarine drilling assembly and method for inserting a foundation element into the soil of a body of water - Google Patents

Abstract

The arrangement (10) has a star-shaped submersible working platform (20) placed onto a bed of a body of water. Ground contact elements (22) are arranged on the working platform for aligning the working platform on the bed of the body of water in an adjustable manner. A cylindrical guide pipe (30) is arranged on the working platform to receive and guide a drilling tool (40) driven by a drill drive. The guide pipe is supported on the working platform in a displaceable and rotatable manner. A guide pipe drive (60) drives the guide pipe on the working platform in a rotating manner. An independent claim is also included for a method for introducing a foundation element into a bed of a body of water with an underwater drilling arrangement.

Description

The invention relates to an underwater drilling assembly for introducing a foundation element in a body of water with a retractable platform for placement on the river bottom, a plurality of ground contact elements, which are arranged to align the platform on the bottom of the water adjustable on the platform, and at least one arranged on the platform guide tube The invention relates to a method for introducing a foundation element into a waterbed with an underwater drilling arrangement.

Such a drilling arrangement is used, for example, the introduction of foundation elements for offshore wind turbines or for flow turbines tidal power plants in the sea.

A generic prior art, for example, from the GB 2 469 190 A out. After this known method, the work platform is first placed on the bottom of the water. By means of a horizontal adjusting device on the working platform, a guide tube with receiving hopper is brought into a specific position in which a borehole is to be created in the water bottom. Subsequently, a rotationally driven drilling tool is inserted axially into the guide tube and sunk to form the borehole in the riverbed.

A similar drilling assembly with a tiltable guide tube is from the GB 2 473 683 A known, wherein a pile tube is introduced into the soil to form the foundation element.

In strong submarine currents there is a risk that the platform will be moved or driven off before the first hole is introduced. The danger exists in particular if, in addition, the large drilling tool is inserted into the guide tube on the working platform, as this results, at least in the short term, in a considerable attack surface for the flow. Even when inserting the drilling tool in the guide tube due to never completely avoidable inaccuracies under water on the platform significant lateral forces are applied, which lead to an undesirable displacement of the platform on the bottom of the water. An accurate position creation of the foundation element is then not possible.

The WO 2010/015799 A2 discloses a generic drilling assembly and teaches a method in which, to form the foundation member, first a first outer pile tube is introduced by flushing and then a second inner pile tube is drilled into a body of water. The two pipes are cemented in the riverbed.

An improved method is from the EP 23 22 724 A1 known. In this underwater drilling arrangement a plurality of sleeve-shaped guide tubes are arranged on the working platform, in each of which a tubular foundation element is already arranged, which simultaneously receives a drilling tool. The tubular foundation element is held by a clamping device on the platform and can be lowered after creating a hole in this.

From the WO 02/18711 A1 and the EP 0 301 116 A1 each drive units for drilling tools show that can be lowered under water.

From the US 3,029,608 is a well-known anchoring process, in which a foundation element is introduced by means of a vibration drive in the water bottom, the vibration drive is arranged above the water surface above a platform.

The invention has for its object to provide an underwater drilling assembly and a method for introducing a foundation element in a body of water, with which a foundation element is particularly accurately inserted position.

The object is achieved on the one hand by an underwater drilling arrangement with the features of claim 1. On the other hand, the object is achieved by a method having the features of claim 8. Preferred embodiments of the invention are specified in the respective dependent claims.

The underwater drilling arrangement according to the invention is characterized in that the guide tube slides longitudinally displaceable and rotatable on the working platform is and that on the platform a guide tube drive for rotating driving the guide tube is provided.

A basic idea of the invention is not to store a working platform alone with the floor standing elements arranged on the side of the working platform at the bottom of the water. Before introducing the actual borehole, it is provided according to the invention that the mounted on the platform guide tube is driven by a self-rotating guide tube itself and is screwed into the ground. This creates an additional anchorage of the working platform in the riverbed. The guide tube is driven a few meters into the river bottom. This is done by means of a arranged on the platform guide tube drive.

After this anchoring of the work platform, the foundation element can then be introduced by a conventional drilling tool into the water bottom, wherein the drilling tool is guided along the guide tube. After the guide tube is already partially introduced into the body of water, an improved guidance of the drilling tool in the ground is achieved as well. Transverse forces on the guide tube during insertion of the drilling tool or a foundation element are intercepted directly in the water body, so that no displacement of the working platform takes place.

According to the invention, it is advantageous that the guide tube has at its upper end an insertion funnel for insertion of the drilling tool. This usually conical funnel allows in the work under water easier insertion of the drilling tool or a pile-shaped foundation element in the guide tube. The insertion funnel can also be designed as a catching device only on part of the circumference.

Furthermore, it is preferred according to the invention that the guide tube has at its lower end cutting teeth for removing soil material. The cutting teeth are in particular arranged annularly on the lower edge of the guide tube. The guide tube is thus formed in its lower region similar to a drill pipe, so that it can also be cut into harder soil material, such as rock or rock.

The guide tube is rotatably driven by a guide tube drive, which preferably acts on the outside of the guide tube. The guide tube drive can be arranged in a simple manner on the platform next to the guide tube. The invention provides as a preferred embodiment that the guide tube drive has at least one collet drive with collet which engages around and clamps the guide tube, wherein the collet is rotatable about a predetermined angle of rotation via at least one rotational cylinder arranged transversely to the tube axis.

The collet acts on at least a portion of the outer circumference of the guide tube. By appropriate clamping cylinder so a non-positive connection between the collet and the guide tube. Subsequently, the collet on laterally disposed torsion, which act substantially tangentially to the outside of the cylindrical guide tube, displaced and thereby rotated about the axis of the guide tube by a predetermined angle of rotation. Thereafter, the tension of the collets is released and the collet moved back by retracting the Verdrehzylinder in the starting position. It can then be done a new tightening and twisting of the guide tube.

With such a collet drive a simple, compact and high-torque rotary drive for the guide tube is achieved. The discontinuous operation of such a collet drive is sufficient to drive the guide tube preferably one meter to five feet deep into the body of water for anchoring the platform.

In order to enable a sufficient propulsion for screwing the guide tube into the body of water, a coil can be provided by strips on the outside of the guide tube. According to the invention, however, it is particularly preferred that the collet drive has at least one feed cylinder arranged longitudinally of the drilling axis through which the collet chuck and the clamped guide tube are movable in the direction of the drilling axis. Thus, forces defined with the feed cylinder can be applied parallel to the axis of the guide tube in the direction of the body of water. This allows a good and reliable feed during insertion of the guide tube.

According to the invention, it is further preferred that the drill drive of the drilling tool can be fixed to the guide tube. The drilling drive for the drilling tool is a drive unit known in the prior art for continuously rotating driving of the drilling tool. The drilling tool may be a conventional drill head or a drill pipe, which itself remains as a foundation element in the ground. The drill drive is preferably relatively firmly attached thereto via clamps on the top of the guide tube. After creating the borehole by means of the boring tool, the boring drive can be released again from the guide tube and removed from the working platform. For this purpose, the drill drive can be stored in a known manner on a rope and be retrievable on a watercraft. Subsequently, a pile-shaped foundation element can be inserted into the borehole and anchored therein with concrete.

To align the platform on the bottom of the river, it is also advantageous according to the invention that the ground contact elements are adjustable by means of lifting cylinders. In this way, by an individual adjustment of the stroke of the lifting cylinder unevenness of the body of water can be compensated. As a result, a vertical orientation of the guide tube can be adjusted. According to the invention, at least three ground contact elements are arranged approximately in the shape of a star on the outer circumference of the working platform. Depending on the purpose of the work platform and more ground contact elements may be provided. These can be designed for a first anchoring of the work platform itself with tips for penetrating into the body of water. In principle, a rotating drive of the ground contact elements is possible, so that the ground contact elements are drilled for anchoring the working platform in the body of water at least for a small area.

The above-mentioned object is further achieved by a method for introducing a foundation element into a body of water with an underwater drilling arrangement, in which a working platform of the underwater drilling assembly is lowered onto the bottom of the water and placed with the ground contact elements on the bottom of the water, a guide tube by means of a Führungsrohrbohrantriebes is drilled into the body of water and then an inserted into the guide tube drilling tool is driven by a rotary drive, wherein a borehole is formed for receiving the foundation element. In particular, the advantages described above can be achieved with this method.

For a simple and high-torque introduction of the guide tube, it is provided according to the invention that guide tube is driven discontinuously by means of a collet drive as a guide tube drive.

For driving the drilling tool, another drive is preferably provided, wherein it is preferred according to the invention that the drilling tool is driven by means of the drilling tool, which is designed as a continuously operating rotary drive. In this way, a constant rotational movement can be generated with a constant torque, which is particularly advantageous when creating deep holes.

Furthermore, it is advantageous according to the invention that the drill drive is releasably fixed to the guide tube. The drill drive can already be determined when lowering the platform on the bottom of the river on the guide tube. Alternatively, the drill drive can also be introduced into the guide tube at a later time, when the work platform is already arranged on the seabed. In particular, a plurality of guide tubes may be arranged on the work platform, so that after creating a first hole of the drill drive 42 can be solved with the drilling tool again from the guide tube and then inserted into a second guide tube for drilling a second hole.

For an efficient creation of a foundation element, it is provided according to the invention that the borehole is filled during retraction of the drilling tool with a curable composition which cures to the foundation element. In this case, the drilling tool may be approximately a flushing drill head, through which first soil material is removed and rinsed out of the borehole. Subsequently, a hardenable mass, in particular concrete, for forming the foundation element into the borehole can be introduced through a core tube of the drilling tool during withdrawal of the drilling tool from the borehole.

Further, it is advantageous according to the invention that during or after the formation of the foundation element, the guide tube is again removed from the ground and lifted off the ground with the working platform. For this purpose, the guide tube be firmly clamped to the work platform. The platform can then be removed via a corresponding hoist winch and / or activation of the lifting cylinder of the ground clearance elements from the bottom of the water. Optionally, the release of the guide tube from the bottom of the water can also be supported by a rotational movement by means of the guide tube drive.

Fig. 1

eine Seitenansicht einer erfindungsgemäßen Unterwasser-Bohranordnung;

Fig. 2

eine Draufsicht von oben auf die Unterwasser-Bohranordnung von Fig. 1;

Fig. 3

eine Seitenansicht einer weiteren erfindungsgemäßen Unterwasser-Bohranordnung mit eingeführtem Bohrwerkzeug und

Fig. 4

eine geschnittene Darstellung der Unterwasser-Bohranordnung von Fig. 3.

The invention will be further elucidated on the basis of preferred exemplary embodiments, which are illustrated schematically in the attached drawings. In the drawings show:

Fig. 1

a side view of an underwater drilling assembly according to the invention;

Fig. 2

a top view of the underwater drilling assembly of Fig. 1 ;

Fig. 3

a side view of another underwater drilling assembly according to the invention with inserted drilling tool and

Fig. 4

a sectional view of the underwater drilling assembly of Fig. 3 ,

A basic structure of an underwater drilling assembly 10 according to the invention is based on the Figures 1 and 2 out. This has a star-shaped platform 16 with three each with the same angular distance to each other radially extending horizontal base struts 18. Of the basic struts 18, a drum-shaped frame 14 formed as a beam construction extends vertically upwards. The frame 14 is additionally connected via diagonal bracing struts 16 to the base struts 18. At the connection points of the stiffening struts 16 and the base struts 18 each of the ground contact elements 22 are arranged. These have a stamp, which are vertically adjustable via a lifting cylinder 24. At the bottom of the actuated by the lifting cylinder 24 stamp anchoring elements 26 are arranged. These anchoring elements 28 may be formed as tips or cutting teeth, so that the ground contact elements 22 can be anchored in the body of water.

For additional anchoring of the platform 20, a cylindrical guide tube 30 is rotatably mounted and longitudinally displaceable according to the invention within the drum-shaped frame 14. On the underside of the guide tube 30, a smaller diameter sprocket with cutting teeth 34 is formed. At the top of the Guide tube 30 is an at least segmentally formed insertion funnel 32 is provided, which facilitates the capture and insertion of a cylindrical drilling tool 40 in the guide tube 30. The drilling tool 40 is supplied via a supply line 44 with energy, rinsing liquid and / or curable material, in particular concrete, from a supply ship, not shown. The working platform 20 is also connected to the supply vessel via a cable and winch arrangement, not shown, and is supplied with energy from this.

Another inventive underwater drilling assembly 10 in a modified form is in the Figures 3 and 4 shown. The given same reference numerals designate the parts with the same function, reference being made to the preceding description.

As in the previously described embodiment, the work platform 20 has base struts 18 and stiffening struts 16 in a star-shaped arrangement extending between the riser elements 22 and the drum-shaped scaffolding frame 14. The base struts 18 are employed in this embodiment as the stiffening struts 16 at an acute angle to a drilling axis 12.

According to Fig. 4 The ground contact elements 22 comprise a housing 23, which receive the actual lifting cylinder 24. On the piston of the lifting cylinder 24 extendable, columnar stamp 28 are arranged, on the underside of which are arranged anchoring elements 26 for anchoring in the bottom of the water.

For additional anchoring, the guide tube 30 is mounted axially adjustable and rotatable in the drum-shaped frame 14. For this purpose, a guide tube drive 60 with two collet drives 61 a and 61 b is provided. The two collet drives 61 a, 61 b each have a guide tube 30 embracing collets 62a, 62b, which are by means of a clamping cylinder, not shown, for non-positive retention of the guide tube 30 can be applied to this. By means of three horizontally directed torsion cylinders 64a, 64b, the rotatably mounted collets 62a, 62b can be rotated together with the guide tube 30 by a predetermined angle of rotation. The twisting movement can thereby for advancing the guide tube 30 by an axial movement along the drilling axis 12th get supported. For this purpose, a vertically arranged feed cylinder 66 between the collet 61 and the frame 14 is arranged.

The two collet drives 61a, 61b are axially spaced and rotated in the circumferential direction to each other. To achieve an at least quasi-continuous rotary drive, a first collet drive 61 a can firstly perform a rotary movement, while the other second collet drive 61 b is reset in its starting position. Thus, the two collet drives 61 a, 61 b each alternately perform a rotational movement of the guide tube 30 or reset.

By screwing the guide tube 30 into the body of water, a reliable anchoring and support of the platform 20 is achieved. Subsequently, the drilling tool 40 can then be introduced into the guide tube 30 via the insertion funnel 32.

As seen from the cross-sectional view Fig. 4 Removable, while the drilling tool 40 has a drill drive 42 with a housing 43 which is fixed by means of hydraulically operated clamping elements 52 on the inside of the guide tube 30. The continuously rotating auger drive 42 drives a drill pipe 50 at the lower end of which is disposed a wellhead 46 for processing rock material. In addition to the rotational movement of the drill drive 42, a drill feed cylinder 48 is arranged, which can additionally apply an axial force to the drill head 46.

The drilling tool 40 with the drill drive 42 is connected as a flying drill via a not shown cable assembly with a supply vessel and can be pulled out of the guide tube 30 after completion of drilling. Subsequently, a foundation element can be formed in the borehole, in particular in which a pile is inserted and anchored therein.

Claims (13)

1. Underwater drilling arrangement for introducing a foundation element into a bed of a body of water comprising

   - a submersible working platform (20) for placement onto the bed of a body of water,

   - several ground contact elements (22), which are arranged in an adjustable manner on the working platform (20) for aligning the working platform (20) on the bed of a body of water, and

   - at least one guide pipe (30) arranged on the working platform (20), which is designed to receive and guide a drilling tool (40) driven by a drill drive (42),

   - whereby the guide pipe (30) is supported in a longitudinally displaceable and rotatable manner on the working platform (20) and
   characterized in that

   - on the working platform (20) a guide pipe drive (60) is provided for driving the guide pipe (30) in a rotating manner around its longitudinal axis.
2. Underwater drilling arrangement according to claim 1,
   characterized in that
   at its upper end the guide pipe (30) has an inserting hopper (32) for inserting the drilling tool (40).
3. Underwater drilling arrangement according to claim 1 or 2,
   characterized in that
   at its lower end the guide pipe (30) has cutting teeth (34) for removing ground material.
4. Underwater drilling arrangement according to any one of claims 1 to 3,
   characterized in that
   the guide pipe drive (60) has at least one collet drive (61) with a collet (62), which embraces and clamps the guide pipe (30), whereby the collet (62) can be twisted around a predetermined angle of twist via at least one twist cylinder (64) arranged transversely to the pipe axis (12).
5. Underwater drilling arrangement according to claim 4,
   characterized in that
   the collet drive (61) has at least one feed cylinder (66) arranged longitudinally to the drilling axis (12), through which the collet (62) and the clamped guide pipe (30) can be moved in the direction of the drilling axis (12).
6. Underwater drilling arrangement according to any one of claims 1 to 5,
   characterized in that
   the drill drive (42) of the drilling tool (40) can be secured on the guide pipe (30).
7. Underwater drilling arrangement according to any one of claims 1 to 6,
   characterized in that
   the ground contact elements (22) are adjustable by means of lifting cylinders (24).
8. Method for introducing a foundation element into a bed of a body of water with an underwater drilling arrangement (10), in particular according to any one of claims 1 to 7, in which

   - a working platform (20) of the underwater drilling arrangement (10) is lowered to the bed of a body of water and placed with the ground contact elements (22) onto the bed of a body of water,

   - a guide pipe (30) is driven in a rotatable manner around a longitudinal axis of the guide pipe (30) by means of a guide pipe drive (60) and is drilled into the bed of a body of water and

   - subsequently a drilling tool (40) inserted into the guide pipe (30) is driven in a rotating manner by means of a drill drive (42), whereby a drill-hole is formed for receiving the foundation element.
9. Method according to claim 8,
   characterized in that
   the guide pipe (30) is driven in a discontinuous manner by means of a collet drive (61) as a guide pipe drive (60).
10. Method according to claim 8 or 9,
    characterized in that
    the drilling tool (40) is driven by means of the drill drive (42) which is designed as a continuously operating rotary drive.
11. Method according to any one of claims 8 to 10,
    characterized in that
    the drill drive (42) is releasably secured on the guide pipe (30).
12. Method according to any one of claims 8 to 11,
    characterized in that
    during retraction of the drilling tool (40) the drill-hole is filled with a hardening mass which hardens to form the foundation element.
13. Method according to any one of claims 8 to 12,
    characterized in that
    during or after formation of the foundation element the guide pipe (30) is removed from the ground and lifted with the working platform (20) from the bed of a body of water.

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