DE102010050494B4 - Closure for a borehole - Google Patents

Abstract

A closure for a wellbore (102) having a wall (104) wherein fluid flows into the wellbore (102), comprising: a) a tube (112) insertable into the wellbore (102); b) at least one apron (106) made of a fluid-tight material, b1) wherein the at least one skirt (106) is fixed in a fluid-tight manner to the tube (112); b2) wherein the at least one skirt (106) can assume a folded state towards the tube (112) and a state unfolded away from the tube (112) and towards the wall (104); b3) wherein the tube (112) and the at least one skirt (108) are formed in such a way that, in the state of the at least one skirt (106) folded towards the tube (112), a gap (108) is provided between the at least one skirt (106). and the wall (104) exists when the tube (112) is inserted into the wellbore (102); b4) wherein the at least one skirt (106) has at least one fixing element (302); b5) wherein the hardness of the at least one fixing element (302) exceeds the hardness of the wall (104); b6) so that the at least one fixing element (302) can penetrate into the wall (104) when the at least one skirt (106) is pressed against the wall (104); b7) so that a positive connection between the at least one skirt (106) and the wall (104) can come about; and c) activatable means, c1) wherein activation of the activatable means results in the at least one skirt (106) being able to assume the state unfolded from the tube (112) and towards the wall (104).

Description

Field of the invention

The invention relates to a closure for a borehole in which a fluid, such as oil or gas, flows on.

State of the art

So-called blowout preventers are known from the prior art. A blowout preventer is a series of shut-off valves that are mounted directly over the wellbore in a well. Blowout preventers serve to prevent the escape of a fluid from the wellbore. This is particularly necessary if the drill string is damaged or the bore encounters an overpressure zone.

While drilling, the drill string passes through the blowout preventer. If there is an exit of the fluid, which can not be stopped by other means, occurs in the blowout preventer, a two-stage mechanism in place. In a first stage, seals are activated that seal the outer space around the drill string. From the publication US 1,059,410 B2 Such a device is known. However, this device does not completely seal the space around the drill pipe but merely reduces the flow. Should this not be sufficient to stop leakage of the fluid, in a second stage, the drill pipe within the blowout preventer is severed. Thereafter, a sealing of the blowout preventer by means of gate valves is possible.

However, it is questionable in individual cases whether the dimensioning of the blowout preventer used is sufficient for a transection of the drill string. In 2004, a study commissioned by US federal agencies found that only 3 out of 14 oil rigs had sufficiently strong shears to cut the drill string.

Furthermore, plugs or Rohrdübelpatrronen are known as closure systems for wells. The pamphlets US 4,669,540 A and DE 41 13 315 A1 exemplify such systems. A disadvantage of such closure systems, however, is that they close a hole definitively and forever, so it is not possible to reuse the well after the uncontrolled outflow of the fluid has stopped.

The events in the Gulf of Mexico have shown that the known methods used have significant weaknesses and are very prone to failure in terms of use and operation.

task

The object of the invention is to provide a device for securing a borehole with the potential for closing the borehole, which can be used universally, while avoiding the aforementioned disadvantages of known blowout preventer.

solution

This object is achieved by the invention with the features of the independent claim. Advantageous developments of the invention are characterized in the subclaims. The invention also includes all reasonable and in particular all mentioned combinations of independent and / or dependent claims.

The invention is based on the idea of providing a drill pipe at fixed intervals with a closure which unfolds in case of need or to introduce a closure into a leaked borehole in which a fluid, such as oil or gas, flows up the borehole below the wellbore Seal leaks. A first closure according to the invention for a borehole with a wall has for this purpose a tube which can be introduced into the borehole. The tube may consist of one or more tube segments.

Furthermore, the closure has at least one skirt, which consists of a fluid-tight material and is fixed in a fluid-tight manner to the tube. Thus, no fluid can pass between the tube and the at least one skirt. The at least one skirt can be inserted into the wellbore by means of the pipe.

The at least one skirt may assume a state folded toward or unstretched from the tube, and a state that has been unfolded or stretched away from the tube and towards the wall. The tube and the at least one skirt are formed such that in the folded state of the at least one skirt, there is a gap between the at least one skirt and the wall when the tube is inserted into the wellbore. The fluid can then flow through the gap between the at least one skirt and the wall.

In order to enable a positive connection between the at least one skirt and the wall, the at least one skirt has at least one fixing element. The hardness of the at least one fixing element must be Exceed hardness of the wall. When the at least one skirt is transferred from the state folded towards the tube into the state unfolded from the tube and towards the wall and pressed against the wall, the at least one fixing element can consequently penetrate into the wall. This results in a positive connection between the at least one apron and the wall to conditions. Examples of fixing elements are barbs or an upwardly directed linkage that unfolds and wedges when activated.

To close the gap, the closure has activatable means. Activation of the activatable means causes the at least one skirt to assume the state unfolded from the tube and towards the wall. Activation of the activatable means when the tube has been inserted into the wellbore results in the at least one skirt assuming the state unfolded from the tube and towards the wall, i. H. the at least one skirt is transferred from the folded state to the tube in the unfolded from the pipe and towards the wall state. Activatable agents may, for. B. bars that can hold or release the minimum apron.

Preferably, a frictional and / or positive connection between the at least one skirt and the wall is achieved when the tube has been inserted into the wellbore and the at least one skirt has assumed the state unfolded from the tube and towards the wall. This connection fixes the closure within the wellbore and prevents the closure from sliding out of the wellbore.

The connection between the at least one skirt and the wall is fluid-tight. Further, since the at least one skirt is made of a fluid-tight material and is fluid tightly secured to the tube, the gap is closed so that no fluid can escape through the gap when the tube has been inserted into the well and the at least one skirt is away from the tube and unfolds to the wall unfolded state. The borehole is hereby sealed.

The at least one skirt is preferably designed such that the connection between the at least one skirt and the wall can be released by pulling on the pipe. By pulling on the tube, the closure can thus be removed from the wellbore as needed.

It has proved to be advantageous that the transfer from the state folded towards the pipe in the state unfolded away from the pipe and toward the wall is passively, d. H. takes place by means of a fluid flowing through the borehole fluid on the at least one apron applied pressure. For this purpose, the at least one skirt in the tube-folded state forms with the tube a gap-shaped pocket into which the ascending fluid can penetrate. This has the effect that the pressure required for transferring the at least one skirt into the state unfolded from the tube and towards the wall is achieved.

The activation of the activatable means now leads to the fact that the pressure presses the at least one skirt against the wall, so that the gap is closed and the positive or positive connection between the at least one skirt and the wall comes about.

The at least one apron is preferably designed sack or umbrella-shaped. As the material for the at least one skirt is a flexible material that is resistant to the fluid, d. H. its physical properties do not change upon contact with the fluid. If necessary, the at least one apron can also consist of a textile material or of a metal mesh which is coated for sealing with a suitable substance, if appropriate with a plastic, a polymer based on plants or a biopolymer. Furthermore, certain plastic films or films of a polymer based on plants and possibly biopolymers are suitable as material for the at least one apron. It has proven to be advantageous to steam the foil or the textile material to protect against destruction by the fluid possibly with a metal layer. If necessary, the at least one membrane may be provided with reinforcing ribs to allow proper functioning of the at least one membrane and to prevent damage. Alternatively, the at least one skirt may consist of overlapping plastic or metal lamellae or lamellae of textile material as described above.

In a preferred embodiment, the at least one tube is a drill pipe on which the skirt - or, as will be explained below - the capsule is mounted to deploy as needed and to block the unimpeded flow of fluid.

Instead of the drill string, the pipe in a further preferred embodiment may be a temporary linkage. A temporary linkage is to be understood as meaning any tube other than the drill pipe, which serves for introducing the closure into the borehole and subsequently discharging the fluid.

The rising fluid in the wellbore flows at a certain flow rate. If a certain threshold value of the flow velocity is reached, the at least one apron unfolds. If the flow velocity is too high, the at least one skirt can be destroyed during the transition from the folded state to the pipe in the unfolded from the pipe and towards the wall state. To prevent this, an advantageous development of the invention has a plurality of aprons. These are arranged one behind the other along the tube. At least one skirt thereof is preferably provided with a passage for the fluid. This reduces the kinetic energy of the ascending fluid. An apron located above or behind the apron provided with the passage can protect them from destruction.

If a frictional connection is to be established between the at least one skirt and the wall, the at least one skirt preferably has a rough surface. For this purpose, the at least one apron, for example, with diamonds or fragments of diamonds, d. H. Diamond dust, be coated.

Another embodiment of the closure according to the invention for the borehole has at least one capsule made of a fluid-tight material. Preferably, the material of the capsule is plastically deformable to ensure a stable anchoring of the closure. Suitable would be about metal. The capsule may also consist of a suitable deployable material, such as one of the above-mentioned materials of the apron.

The capsule is formed such that there is a gap between the capsule and the wall when the closure is inserted into the wellbore.

For anchoring in the borehole, the closure has at least one propellant charge. By activation of the at least one propellant the capsule is deployed or expanded. Depending on the selected material, plastic deformation of the capsule occurs. As a result, the capsule is pressed against the wall, so that a positive and / or positive connection between the capsule and the wall is formed.

As propellant are energy storage, such as compressed gases, solid propellant charges or pyrotechnic propellant charges. The released energy unfolds or expands the capsule so that it is pressed against the wall.

The connection between the capsule and the wall is form-fitting fluid-tight by appropriate nature of the outer wall of the capsule. Since the capsule is made of a fluid-tight material, no fluid can escape through the gap when the closure has been inserted into the wellbore and the propellant has been activated. The borehole is hereby sealed.

To connect a pipe with the closure, this has a coupling.

In order to continue to use the wellbore, the closure adjacent the coupling has a passage which extends longitudinally through the closure so that fluid can flow through the closure.

For example, if the drill pipe has been ejected from the borehole due to an accident or has been removed therefrom for another reason, the shutter may be inserted into the hole in a further advantageous development of the invention instead of the at least one pipe on which it is mounted to have a drive. This allows movement of the closure in the fluid. Preferably, the drive is configured as a recoil drive, for example as a rocket engine. Even a propeller engine can be used as a drive.

In order for the drive to be able to introduce the closure into the wellbore against the upflowing fluid, the feed rate of the drive must exceed the flow rate of the fluid in the wellbore. The speed at which the drive advances is to be understood as the speed at which the drive travels relative to the fluid flowing up the borehole.

Instead of the drive, a tube can be used to insert the closure into the wellbore. For this purpose, the closure is attached to the tube. The connection between the closure and the tube is fluid tight. The pipe may be the drill pipe or a temporary linkage.

The Connection between the capsule and the wall is in one advantageous development of the invention frictional and / or non-positive and fluid-tight. For this purpose, the outer surface of the capsule is designed accordingly. In a preferred embodiment, the outer surface of the capsule has at least one fixing element. The hardness of the at least one fixing element must exceed the hardness of the wall, so that the at least one fixing element can penetrate into the wall when the capsule is expanded after introduction of the closure into the wellbore and the outer surface of the capsule is pressed against the wall. This results in a positive connection between the capsule and the wall of the borehole to conditions. Examples of fixing are also about barbs.

In a further development of the closure, the latter can have a fixing pin displaceably mounted relative to the capsule. The at least one propellant can act directly on the at least one fixing pin. By activating the at least one propellant charge, the at least one fixing pin can be at least partially pushed out of the capsule. If the closure is located inside the borehole and if the at least one fixing pin is at least partially pushed out of the capsule by activation of the at least one propellant charge, the at least one fixing pin can penetrate into the wall.

In order to seal the closure against the wall of the borehole, the closure has at least one further propellant charge. By activation of the at least one further propellant charge, the capsule can be unfolded or expanded and pressed against the wall.

In addition, a development of the invention in which the closure can be introduced ballistically into the borehole is advantageous. The closure is thereby accelerated before entering the borehole, that is acted upon by a kinetic energy. This energy is suitable for introducing the closure into the wellbore to a certain depth where it unfolds through appropriate activatable means.

Further details and features will become apparent from the following description of preferred embodiments in conjunction with the subclaims. In this case, the respective features can be implemented on their own or in combination with one another. The possibilities to solve the problem are not limited to the embodiments. For example, area information always includes all - not mentioned - intermediate values and all imaginable subintervals.

The embodiments are shown schematically in the figures. The same reference numerals in the individual figures designate the same or functionally identical or with respect to their functions corresponding elements. In detail shows:

1A a closure for a borehole with a skirt in the folded state towards the tube;

1B a closure for a wellbore with an apron in a state unfolded from the tube and towards the wall;

2 a closure for a wellbore with an apron in the state unfolded from the pipe and towards the wall with seals;

3 a closure for a borehole with reinforcing ribs and fixing elements;

4 a closure for a borehole in the manner of a torpedo; and

5 a movable fixing pin.

1A shows a closure that is in a borehole 102 with a wall 104 is introduced. The closure has an apron 106 on. Between the apron 106 and the wall 104 there is a gap 108 , The skirt 106 is at the top of a pipe 112 attached and located in the tube 112 folded state.

sensors 110 measure data, such as the movement of the pipe 112 , the location of the pipe 112 relative to the wall 104 , the hydrostatic pressure of the fluid surrounding the shutter, the distance that the shutter within the borehole 102 has returned, or the flow rate of the fluid.

The skirt 106 is activated by means in the pipe 112 Fixed folded state. Activation of the activatable means by the sensors 110 give the apron 106 free. Fluid under the apron 106 flows, then leads an opening of the apron 106 cause.

The skirt 106 in from the pipe 112 away and towards the wall unfolded state shows 1B , The pressure that the upflowing fluid has on the apron 106 exercises, presses the apron 106 against the wall 104 , Between the apron 106 and the wall 104 As a result, a frictional and / or positive and fluid-tight connection is formed. Thus closes the apron 106 the gap 108 ,

To improve the density of the connection to the fluid, seals can be used 200 , for example in the form of O-rings, on the apron 106 to be appropriate. This is in 2 in the whole and as a detail Z shown. By the pressure, the fluid flowing on the apron 106 exerts a positive and / or non-positive, fluid-tight connection between the seals 200 and the wall 104 conditions.

The use of a flexible fabric or foil as apron 103 is especially practicable when the pressure that the upflowing fluid has on the apron 106 exercises, is low. At higher pressures, however, the in 3 embodiment shown preferred. This support reinforcing ribs 300 the skirt 106 , The skirt 106 , in the 3 to better illustrate the reinforcing ribs 300 not shown, is positioned upstream of the reinforcing ribs, hence the skirt 106 in the unfolded state against the reinforcing ribs 300 is pressed. The structure of the reinforcing ribs 300 resembles the poles of an umbrella. The reinforcing ribs 300 stabilize the apron 106 center the tube 112 in the borehole 102 and also prevent damage to the apron 106 by the pressure of the fluid on the apron 106 in from the pipe 112 away and to the wall 104 unfolded state.

seals 200 , as in 2 illustrated, are particularly advantageous if the wall 104 of the borehole 102 made of a hard material. A soft wall 104 on the other hand, the use of the Z in detail allows 3 shown fixing elements 302 , The fixing elements 302 are at the reinforcing ribs 300 attached and made of a hard material. In particular, the material of the fixing must 302 be harder than the material of the wall 104 , Preferably have the fixing elements 302 Formations, for example in the form of barbs.

Will the apron 106 in from the pipe 112 away and to the wall 104 unfolded state by the pressure that the fluid on the apron 106 exercises, against the wall 104 This leads to the fact that the formations of the fixing elements 302 in the wall 104 penetration. This results in a positive connection with the wall 104 ,

To protect the material and increase safety, the apron can 106 be opened gradually. In a first step, the fixing elements 302 against the wall 104 pressed, so that the formations of the fixing elements 302 in the wall 104 penetrate and a positive connection to the wall 104 comes about. In a second step, the gap becomes 108 by transferring the apron 106 from that to the pipe 112 folded in from the tube 112 away and to the wall 104 folded out state closed. The fluid now flows through the tube 112 , In a third step, valves are placed in the pipe 112 are closed. This is the hole 102 completely sealed.

In the in the 1A . 1B . 2 and 3 shown embodiments, the apron 106 by means of the pipe 112 , in the preferred embodiment as an equipment element of a drill string, into the wellbore 102 introduced. The closure off 4 is, however, designed in the manner of a torpedo. A jet engine 400 generates enough feed to the closure against the fluid flowing into the hole 102 introduce.

Instead of the apron 106 has the in 4 shutter shown a capsule 401 on. The capsule 401 forms the outer shell of the belly of the closure. The lower part 401 the capsule 401 is hemispherical and with sensors 110 Mistake.

To the hemispherical part of the capsule 401 includes a cylindrical part 401b the capsule 401 at. The cylindrical part 401b the capsule 401 connects the hemispherical part 401 the capsule 401 with its upper part 401c , At the upper part 401c the capsule 401 in turn are guiding elements 402 as well as a clutch 404 appropriate.

The capsule 401 encloses propellant charges 408 and a solid support element 406 with funnel-shaped indentations. Within these indentations are pyrotechnic propellant charges 408 ,

Through the hemispherical part 401 the capsule 401 through the support element 406 , through the jet engine 400 and through the upper part 401c the capsule 401 leads a passage 414 , The passage 414 runs longitudinally through the closure and connects an opening in the spherical part 401 the capsule 401 so with an opening in the upper part 401c the capsule 401 in that fluid can flow through the closure.

The guiding elements 402 serve to stabilize the closure, while this in the borehole 102 is introduced. The sensors 110 meanwhile capture appropriate data. So can the sensors 110 about the depth of penetration of the closure in the borehole 102 measure or damage the wall by means of optical signals 104 determine.

Depending on the acquired data, the sensors initiate 110 the activation of the propellant charges 408 , Due to the energy released as a result, the capsule 401 unfolded or stretched and against the wall 104 pressed.

The capsule 401 is with fixing elements 302 Mistake. The hardness of the fixing elements 302 Must be the hardness of the wall 104 of the borehole 102 exceed. This allows the fixing elements 302 , due to the activation of the pyrotechnic propellant charges 408 in the wall 104 to be able to penetrate, so that the closure by means of a positive connection in the wall 104 anchored. As in detail Y the 4 shown, the fixing elements 302 be designed as a barb.

The energy of the explosion of the propellants 408 causes an increase in the diameter of at least a portion of the capsule 401 , In order to achieve a defined deformation of the capsule 401 To ensure the capsule can 401 , as in detail X the 4 shown, a predetermined breaking point 410 exhibit. Will the capsule 401 dilated, the lower part of the capsule dissolves 401 consisting of the hemispherical part 401 the capsule 401 and the cylindrical part 401b the capsule 401 , along the breaking point 410 from the upper part 401c the capsule 401 , This prevents the capsule from expanding when it expands 401 the remaining components of the closure, such as the passage 414 or the clutch 404 , to be damaged.

The bigger the one between the wall 104 and the capsule 401 Existing gap is, the higher demands will be made on the deformability of the capsule 401 posed. To prevent when expanding the capsule 401 the breaking point of the capsule 401 used material is exceeded, the capsule 401 below the predetermined breaking point 410 have vertically extending pleats.

In the expanded state is the cylindrical part of the capsule 401 plan on the wall 104 at. The hemispherical part of the capsule 401 connects the cylindrical part of the capsule 401 with the inside of the closure. Consequently, between the capsule 401 and the wall 104 no fluid escape. The borehole is now sealed.

Around the borehole 102 continue to use, has the closure next to the clutch 404 - as in detail Z the 4 shown - a valve 412 on. The valve 412 opens and closes the passage 414 , Is the valve 412 closed, no fluid can get out of the hole 102 escape. Is the valve 412 On the other hand, the fluid is opened through the passage 414 and thus passed through the closure.

Save the drawn poppet valve 412 Other types of valves may also be used, e.g. B. cone valves or slide valves. The latter would have the advantage of requiring less force to open.

The coupling 404 serves to connect a pipeline to the closure. This happens after the closure by activating the propellant charges 408 in the wall 104 was anchored. With the valve open 412 the fluid can be discharged through the pipeline and further processed as intended.

The valve may also be open during insertion of the closure into the wellbore to reduce pressure on the closure. One possibility is then to close the valve only when a pipe to the clutch 404 was connected. Such a pipeline 404 is able to absorb parts of the increased forces after closing the valve.

It is possible to have several closures in the 4 shown execution in the borehole 102 introduce.

It is also possible the embodiment as a capsule as an item of equipment of a drill pipe 112 to assemble and into the borehole 102 introduce.

Various embodiments may be combined according to different security considerations.

5 shows a section of the closure with at least one fixing pin 500 , To guide the at least one fixing pin 500 has the carrier element 406 a cylindrical bore 502 on. In the hole 502 is the fixing pin 500 slidably mounted.

The hole 502 connects an opening 504 in the capsule 401 with a spherical ignition chamber 506 , As well as the hole 502 is the ignition chamber 506 in the carrier element 406 that is, from the carrier element 406 surrounded by the carrier element 406 educated.

The hole 502 is not perpendicular, but is inclined at a certain angle to the vertical down. Thus, the fixing pin slips 500 due to its gravity, first along the hole 502 towards the interior of the closure.

The ignition chamber 506 includes a propellant 408 , If this is activated, the released energy drives the fixing pin 500 from the ignition chamber 506 away in the direction of the wall 104 of the borehole 102 , The fixing pin 500 as a result, passes through the between the capsule 401 and the wall 104 existing gap 108 through and penetrates into the wall 104 one. The closure is now on the wall 104 fixed.

The gap 108 Can be closed by the capsule 401 - As described above - unfolded or stretched and against the wall 104 is pressed. At least one propellant 408 thus serves to deploy or expand the capsule, while at least one further propellant 408 the fixing pin 500 in the wall 104 drives.

To prevent the bore 502 and the at least one fixing pin 500 when unfolding or expanding the capsule 401 is damaged, the hole is 502 preferably arranged so that the opening 504 in the capsule 401 above the breaking point 410 in the upper part 401c the capsule 401 located.

LIST OF REFERENCE NUMBERS

102

well

104

wall

106

apron

108

gap

110

sensor

112

pipe

200

poetry

300

reinforcing rib

302

fixing

400

jet propulsion

401

capsule

401

spherical part of the capsule

401b

cylindrical part of the capsule

401c

upper part of the capsule

402

vane

404

clutch

406

support element

408

propellant

410

Breaking point

412

Valve

414

passage

502

drilling

504

ignition chamber

quoted literature

cited patent literature

• US Pat. No. 7,059,410 B2
• US 4,669,540
• DE 41 13 315 A1

Claims (9)

Closure for a borehole ( 102 ) with a wall ( 104 ), wherein a fluid in the wellbore ( 102 ), comprising: a) a tube ( 112 ) that enters the borehole ( 102 ) is insertable; b) at least one apron ( 106 ) of a fluid-tight material, b1) wherein the at least one apron ( 106 ) fluid-tight to the tube ( 112 ) is fixed; b2) the at least one apron ( 106 ) one to the pipe ( 112 ) folded state and one of the pipe ( 112 ) away and to the wall ( 104 ) can take unfolded state; b3) the tube ( 112 ) and the at least one apron ( 108 ) are formed such that in the pipe ( 112 ) folded state of at least one apron ( 106 ) A gap ( 108 ) between the at least one apron ( 106 ) and the wall ( 104 ) exists when the pipe ( 112 ) in the borehole ( 102 ) is introduced; b4) the at least one apron ( 106 ) at least one fixing element ( 302 ) having; b5) wherein the hardness of the at least one fixing element ( 302 ) the hardness of the wall ( 104 ) exceeds; b6) so that the at least one fixing element ( 302 ) in the wall ( 104 ) can penetrate, if the at least one apron ( 106 ) against the wall ( 104 ) is pressed; b7) so that a positive connection between the at least one apron ( 106 ) and the wall ( 104 ) can come about; and c) activatable agents, c1) wherein activation of the activatable agents results in the at least one apron ( 106 ) from the pipe ( 112 ) away and to the wall ( 104 ) can take unfolded state. Closure according to the preceding claim, characterized in that the at least one tube ( 112 ) is a drill pipe. Closure according to claim 1, characterized in that the at least one tube ( 112 ) is a makeshift linkage. Closure according to one of the preceding claims, characterized by a plurality of aprons ( 106 ), along the pipe ( 112 ) are arranged one behind the other. Closure for a borehole ( 102 ) with a wall ( 104 ), wherein a fluid in the wellbore ( 102 ), comprising: a) at least one capsule ( 401 ) of a fluid-tight material, a1) the capsule ( 401 ) is formed such that a gap ( 108 ) between the capsule ( 401 ) and the wall ( 104 ), when the plug enters the borehole ( 102 ) is introduced; b) at least one propellant ( 408 ), b1) wherein by activating the at least one propellant ( 408 ) the capsule ( 401 ) can be expanded; and with c) a coupling ( 404 ) for connecting a pipeline to the closure; d) one passage ( 414 ) passes through the closure so that the fluid can flow through the closure and be discharged through the conduit. Closure according to the preceding claim, characterized by a drive ( 400 ), which allows movement of the closure in the fluid. Closure according to claim 5, characterized in that the closure on a pipe ( 112 ), which is insertable into the wellbore, is mounted. Closure according to one of claims 5 to 7, characterized in that the outer surface of the capsule ( 401 ) at least one fixing element ( 302 ) having; the hardness of the fixing element ( 302 ) the hardness of the wall ( 104 ) exceeds; so that the at least one fixing element ( 302 ) in the wall ( 104 ) can penetrate when the outer surface of the at least one capsule ( 401 ) against the wall ( 104 ) is pressed. Closure according to one of claims 5 to 8, characterized in that the closure at least one fixing pin ( 500 ), which by activating the at least one propellant ( 408 ) at least partially from the capsule ( 401 ) can be pushed out; the hardness of the at least one fixing pin ( 500 ) the hardness of the wall ( 104 ) exceeds; so that the at least one fixing pin ( 500 ) in the wall ( 104 ) can penetrate when the at least one fixing pin ( 500 ) by activation of the at least one propellant ( 408 ) at least partially from the capsule 401 is pushed out.

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