WO2009121882A1

WO2009121882A1 - Method for in-situ repair of a hole in pipe in pipe tubulars

Info

Publication number: WO2009121882A1
Application number: PCT/EP2009/053813
Authority: WO
Inventors: Claire Dean; Wilhelmus Hubertus Paulus Maria Heijnen
Original assignee: Mærsk Olie Og Gas A/S
Priority date: 2008-03-31
Filing date: 2009-03-31
Publication date: 2009-10-08
Also published as: DK200800468A; EP2304306B8; EP2304306B1; DK178422B1; EP2304306A1

Abstract

A method for the in-situ repair of a hole in pipe in pipe tubulars (2). The method comprises the following steps: running a hole sealing device (10) into the pipe in pipe tubing, identifying a hole (7) in the tubing, and injecting a sealant (8) into the hole via the hole sealing device. In this way, holes in pipe in pipe tubulars can be repaired without the costs of removing the inner tubular from the outer tubular. A device suitable for the method is also provided.

Description

Method for in-situ repair of a hole in pipe in pipe tubulars

The current invention relates to a method for the in-situ repair of holes in well tubulars used in the production of hydrocarbons or fluids and/or the injection of fluids into earth formations. Three non-limiting examples of such uses are the production of oil, production of natural gas and the injection of water into a formation. The current invention also relates to a device used in said method.

In this specification, the term "pipe in pipe" is used to represent those well tubulars which are arranged inside another well tubular. One typical example is "production tubing" which is the well tubular used in the production of oil and which is inserted into a casing, a liner or the like. Production tubing differentiates itself from other forms of well tubulars in that it is usually designed to be removed and replaced if necessary, unlike casing which is usually cemented into the well bore and becomes an integral part of the well. The current specification uses production tubing as the main example of pipe in pipe tubulars. The protection of the current invention shall however not be limited to production tubing, but be extended to cover all forms of pipe in pipe tubulars.

A definition of "production tubing" is: "A wellbore tubular used to produce reservoir fluids. Production tubing is assembled with other completion components to make up the production string. The production tubing selected for any completion should be compatible with the wellbore geometry, reservoir production characteristics and the reservoir fluids."

A definition of "casing" is: "Large-diameter pipe lowered into an open hole and cemented in place. The well designer must design casing to withstand a variety of forces, such as collapse, burst, and tensile failure, as well as chemically aggressive brines. Casing is run to protect fresh-water formations, isolate a zone of lost returns or isolate formations with significantly different pressure gradients.

It should also be noted that the person skilled in the art will know that production tubing and casing are sometimes defined with respect to their diameter. Tubulars with a diameter of larger than 4.5" are sometimes defined as casing while tubulars with a diameter of less than 4.5" are defined as tubing. However, as will also be known to the person skilled in the art, in certain applications, tubulars with a diameter of more than 4.5" are used as production tubing. Therefore the purpose of the current specification, production tubing should be understood as that tubular which is inside a casing or liner, no matter what the size of the tubular.

Description of related art

In the following, the examples and discussion will focus mainly on "production tub- ing". However, the person skilled in the art should understand that the current invention can be applied to all other forms of "pipe in pipe" tubulars.

Conventional techniques for repairing holes in pipe in pipe tubulars include the following five techniques.

1. Pulling the production tubing out & replacing the damaged portion

2. Installing a straddle over the damaged portion

3. Installing an expandable tubing patch over the damaged portion

4. Treatment of the damaged area with a pressure activated liquid sealant 5. Pumping cement down the production tubing and out through the damaged area

However, the currently available methods all suffer from drawbacks. For example, the first option, pulling the production tubing and replacing the damaged portion, involves high costs & complicated operational logistics.

The second option, installing a straddle, restricts the internal diameter of the production tubing after installation. The internal diameter of the straddle is typically only 1/3 to 1/2 of the internal diameter of the production tubing in which it is installed. This significantly reduces the amount of flow which can be pumped through the production tubing after the straddle has been installed.

The third option, installing an expandable tubing patch, typically results in less of an ID restriction than a straddle but many of the commercially available products suffer from one or more of the following problems: they are not proven gas tight, they are not available in sufficiently small sizes to patch holes in tubing, and they require either coiled tubing or drill pipe for deployment, restricting applicability & increasing cost.

The fourth option, using pressure activated sealants, is typically used on small leaks such as pinholes and leaking connections. Pressure activated sealants are designed to be pumped down into the production tubing and out through the leaks. A pressure drop through the leak site causes the sealant fluids to polymerize into a flexible solid. The polymerization process occurs only under differential pressure. The sealant is typically deployed by pumping the fluid down the leaking production tubing, or by using either coiled tubing or a wireline bailer. This technique has, however, not been extensively applied to larger holes and its success rate for this application is not expected to be high.

The fifth option is to use cement. However, materials such as cement do not have the appropriate physical properties to spread evenly into the annulus & seal off a tubular hole. It is therefore required to pump large quantities of cement in order to be sure that a hole is effectively sealed. This is both time consuming and expensive. The use of cement is also a more permanent solution since the cement will fill a large portion of the annulus between the production tubing and the casing, thereby making it near to impossible to remove the production tubing if desired.

It is to be noted that during the drafting of this specification, after the invention had been made, devices were found in the patent literature which are used in the reparation of sewer lines. See for example EP 0 496 289. We note that even though they might be similar in appearance to the devices discussed in the current specification, the devices used in sewer lines are not suitable for use in down the hole reparation of production tubing. Furthermore, the person who works daily with drilling opera- tions would not have been inspired by the methods and tools used in the reparation of sewer pipes due to the differences in working environment and the difference in the demands made on the equipment. These devices should therefore not be used when discussing the patentability of the current invention. We also note that the reparation of the production tubing of a well is quite different from the reparation of the casing of a well since the casing is permanently fixed in the well, whereas the production tubing is meant to be removable. The demands of the reparation are therefore quite different.

Summary of the invention

A first aspect of the current invention is to provide a method as mentioned in the introductory paragraph whereby one can repair holes in pipe in pipe tubulars in-situ, thereby avoiding the cost & operational logistics associated with pulling & replacing damaged pipe in pipe tubulars.

A second aspect of the current invention is to provide a method as mentioned in the introductory paragraph which is designed to minimize the amount which the repair reduces the inner diameter of the pipe in pipe tubulars.

A third aspect of the current invention is to provide a method as mentioned in the introductory paragraph which can be deployed on wireline.

A fourth aspect of the current invention is to provide a method as mentioned in the introductory paragraph which can provide a gas tight seal in typical production tubing sizes.

A fifth aspect of the current invention is to provide a method as mentioned in the introductory paragraph whereby the reparation created by the device is not dependent on differential pressure in order to solidify & develop mechanical strength.

A sixth aspect of the current invention is to provide a method as mentioned in the introductory paragraph whereby fluid flow can be maintained in the annulus between an inner pipe and an outer pipe after the reparation.

A seventh aspect of the current invention is to provide a method as mentioned in the introductory paragraph whereby the pipe in pipe tubing is strengthened in the area of the reparation. The aspects mentioned above are solved in part by a method as mentioned in the introductory portion which comprises the steps of: running a hole sealing device into the pipe in pipe tubular, identifying the hole in the pipe in pipe tubular, and injecting a sealant material into the hole via the hole sealing device.

In this way, the sealing accumulates predominantly on the outside of the tubular being treated. The device and method of the invention thereby minimise the thickness of the layer that sets on the inside of the tubing, thereby resulting in minimum reduction in internal diameter. This minimizes any restriction to flow and enables future intervention activities to be carried out below the reparation.

In a first embodiment, the sealant material used could be a two component epoxy. By changing the mixture of the epoxy, the properties of the sealant material can be changed and adjusted to the needs of the particular situation.

The method could also comprise the step of rotating the hole sealing device in the pipe in pipe tubular until a sealant material injecting nozzle of the hole sealing device faces the hole in the pipe in pipe tubular. The method could also comprise the step of pressing the hole sealing device against the inner surface of the production tubing such that a seal is established around the hole. In this way, sealant is only applied to the inside surface of the pipe in pipe tubular locally at the location of the hole.

In order to strengthen the area around the hole, the step of injecting a sealant material into the hole, could inject just enough sealant material to partially fill the annulus between the production tubing and the casing.

In a preferred embodiment of the method, a thin foil or a non-stick material could be arranged between the inner surface of the production tubing and the device before the sealant material is injected into the hole. In this way, the hole sealing tool is prevented from sticking to the production tubing when the sealant hardens. The invention also relates to a device which is suitable for a method as mentioned in the introductory paragraph. Such a device could comprise an elongated seal having a longitudinal axis which is parallel with the longitudinal axis of the production tubing and which is arranged to establish a seal around an area of the inner surface of the production tubing when the device is pressed against the inner surface of the production tubing. In this way, the device is arranged to focus the sealant material at the area of the hole. In addition, the seal created can strengthen the production tubing around the hole via the elongated patch which is formed.

The device could also be arranged such that it comprises means for holding a foil between the sealant and the device, such that sealant does not fasten the device to the inner surface of the production tubing.

In one embodiment of the device, the device could comprise a mechanism with a mechanical arm which is arranged to press the device against the inner surface of the production tubing opposite the mechanical arm. The mechanical arm can ensure that the seal is firmly pressed against the inner surface of the production tubing.

The device could also comprise a mechanism which comprises a threaded rod, a threaded nut arranged on the threaded rod and an arm attached to the threaded nut, where rotation of the threaded rod causes the arm attached to the threaded nut to extend from the housing. This is a simple way to generate a large mechanical force with small energy requirements and in an elongated device.

It should be emphasized that the term "comprises/comprising" when used in this specification is taken to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof.

Brief description of the drawings

In the following, the invention will be described in greater detail with reference to embodiments shown by the enclosed figures. It should be emphasized that the em- bodiments shown are used for example purposes only and should not be used to limit the scope of the invention.

Figure 1 shows a perspective view of a portion of some production tubing having two holes through the side wall of the tubing, said production tubing being arranged inside a casing shown in section.

Figure 2 shows a schematic cross section view of a portion of the production tubing of figure 1 and well annulus, said section comprising a hole through the production tubing.

Figure 3 shows the cross section view of Figure 2 after the hole has been repaired using an embodiment of the method of the current invention.

Figure 4 shows a schematic side view of a first embodiment of a device for performing the method according to the invention.

Figure 5 shows a schematic bottom view of the device of figure 4.

Figure 6 shows an end view of the device of figure 4 before activation.

Figure 7 shows an end view of the device of figure 4 after activation.

Figure 8 shows a schematic front view of a second embodiment of a device for per- forming the method according to the invention.

Detailed description of the embodiments

Figure 1 shows a schematic and over simplified view of a typical well installation 1. A typical well installation comprises a casing 2 which is usually permanently installed in a well bore hole 3. The casing 2 is usually secured in place by injecting cement 4 between the outer surface of the casing and the inner surface of the well bore 3. In this way, the casing is permanently secured in the well bore hole. Production tubing 5 is arranged inside the casing. The production tubing is arranged to be removable, so it is not permanently connected to the bore hole or the casing. An annulus 6 is therefore formed between the outer surface of the production tubing 5 and the inner surface of the casing 2.

The production tubing 5 shown in figure 1 has two holes 7 which go through the side wall of the production tubing. The holes could be due to any number of reasons. Three non limiting examples of causes of holes in production tubing are corrosion, erosion and damage due to tools working inside the production tubing. However, many other reasons exist as will be known to the person skilled in the art.

Figure 2 shows a cross section through one side of the well bore assembly showing one of the two holes through the wall of the production tubing 5. Figure 3 shows the same cross section as shown in figure 2, but after the method according to one em- bodiment of the current invention has been performed. In this case, epoxy 8 has been injected into the hole such that the epoxy fills the hole. The epoxy also partially fills the annulus 6 between the casing and the production tubing. However, it should be noted that in most cases, the epoxy in the annulus will only fill the volume of the annulus immediately around the hole. Usually, when looking at the epoxy material in the annulus in a direction perpendicular to the axis of the hole, the epoxy material patch will be approximately circular. In other words, the epoxy does not wrap around the entire outer surface of the production tubing. In this way, the fluid flow through the annulus is not blocked by the reparation. It should however be noted that if it is desired to block off the fluid flow through the annulus, then an increased amount of epoxy could be injected through the hole. If enough epoxy is injected into the annulus, the epoxy will eventually form an annular blockage in the annulus thereby preventing fluid flow through the annulus.

As can be seen in the figure, the thickness T of the epoxy layer on the inside of the production tubing is thin and does not present any serious hindrance to flow through the tubing or to tool access to the production tubing below the patch. The layer of epoxy on the inside of the tubing however also functions as a reinforcement of the reparation. The layer of epoxy bonds to the inner surface of the tubing and prevents the plug from pushing out through the hole. In order to further increase the strength of the repair, the epoxy material could be reinforced with fibres or other strength increasing additives.

It should also be mentioned that if enough epoxy is injected so that the epoxy reaches the inner surface of the casing, the epoxy can further support the outer surface of the production tubing in the area of the hole. In this way, the repair not only plugs the hole, but also reinforces the tubing, both from the inside via the thin layer of epoxy and from the outside via the epoxy which pushes against the inner surface of the casing.

In order to prevent the hole sealing device used to inject the epoxy from bonding to the production tubing, a thin foil 9 is arranged between the device and the epoxy. When the epoxy is injected into the hole, the epoxy will fill up the thin space between the inner surface of the tubing and the foil. When the epoxy hardens, the ep- oxy will bond to the foil. When the device is pulled out of the well, the foil remains in the well, bonded to the repair. In another embodiment, Teflon or another non-stick material such as a mould release agent could be arranged on the outer surface of the device.

Figures 4-7 show schematic details of a first embodiment 10 of a hole sealing device which is suitable for performing a method which can be used to establish a plug such as the one shown in figure 3.

The hole sealing device 10 comprises a tubular body 1 1 which has an outer diame- ter which is smaller than the smallest inner diameter of the production tubing string 5. An elongated semi rectangular seal 12 is arranged on one outer surface of the tubular body. The elongated seal has a longitudinal axis which is arranged parallel to the longitudinal axis of the tubular body. Due to the elongated shape of the seal, it is possible for the device to fill multiple holes within an area defined by the perimeter of the seal. It should however be noted that shapes other than semi rectangular could also be used. An oval seal or a circular seal could also be used. The semi rectangular seal however has the advantage that it has a large area which increases the area which can be repaired in one operation. The seal could be made in many different ways. One example is as an inflatable bladder having a tubular cross section. The bladder could be filled with a fluid, either a gas or a liquid, or it could be filled with a semi solid material, such as for example foam or an elastic material.

The seal is designed to be compressed when the device is pressed up against the inner surface of the production tubing and thereby create a well defined sealed volume between the inside of the production tubing and the device. Wheels 13 or pads are arranged on the same side of the device as the seal in order to prevent the seal from coming into contact with the inner surface of the production tubing while the device is run into place. The wheels are mounted to the body of the device via springs 14 such that the wheels retract into the body of the device when the device and therefore the seal 12 are pressed against the inner surface of the production tubing. In another embodiment, (not shown) the seal could be retracted into the body of the device when not in use. In this way, wheels or pads are not necessary to protect the seal. One example of this could be an inflatable seal (not shown) which when deflated does not protrude from the body of the device.

The device comprises a fluid injection outlet 15 arranged in the center of the area surrounded by the seal. A valve 16 controls the flow of fluid out of the fluid injection outlet. In the current embodiment, the composition of the epoxy is determined at the surface before the device is put into the well. The epoxy is usually a two component system which is mixed inside the body of the device just before being injected into the hole.

The device could also comprise a sensor (not shown) which is able to scan the inner surface of the production tubing to locate holes in the production tubing. The sensor can be one of many different possible types. The person skilled in the art of sensors will be able to specify a number of different options.

The device can also comprise means 26,27 for pressure testing the hole and the repair. Before injecting the sealant into the hole, it is usually desired to be certain that there is a hole which needs to be filled. If the device is placed incorrectly, then the sealant injected by the device will remain in the production tubing. In addition, after the sealant has been injected, it is desired to test the success of the repair.

In the current embodiment, these means for pressure testing the hole and the repair comprise a second fluid inlet (26) which injects for example N2 gas into the sealed volume. The flow of gas is controlled via a valve 27. The means could also comprise a pressure sensor (not shown) which could measure the pressure development in the sealed volume. If there is a pressure decay in the sealed volume then there is a hole. If the pressure remains constant, then there is no hole. If the pres- sure is supplied by a motor driven pump, then instead of using a pressure sensor, the pressure could be measured by measuring the amount of current drawn by the motor driving the pump. The test could also be performed by injecting a small amount of gas or fluid into the sealed volume and watching the response in the relevant annulus at the top of the well bore.

The device furthermore comprises a mechanism 17 which is able to press the device and the seal against the inner surface of the production tubing. In the embodiment shown in figures 4-7, the mechanism is arranged on the side of the body which is opposite to the seal. The mechanism comprises a type of mechanical arm which is designed to extend out of the housing and press against the inner surface of the production tubing, thereby pressing the device itself against the inner surface of the production tubing opposite to the mechanism.

The mechanism 17 in this embodiment comprises a threaded rod 18 which is ar- ranged in the body of the device and parallel to the longitudinal axis of the body. A motor 19 is arranged to rotate the threaded rod. Bearings 20 support the threaded rod in the body. A threaded nut 21 is arranged on the threaded rod and is prevented from rotating by a sliding connection (not shown) to the body. The threaded nut therefore moves back and forth along the threaded rod when the rod rotates. One end 22 of a two arm linkage 23 is connected to the threaded nut. The other end 24 of the two arm linkage is fixed to the body. A wheel 25 is arranged at the middle joint of the two arm linkage. When the threaded nut moves back and forth the wheel is therefore forced in and out of the body of the device. The wheel 25 of the mechanism can therefore be pressed against the inner surface of the production tubing by rotating the threaded rod in a first direction. When the wheel 25 presses against the inner surface, the device is forced against the opposite side of the production tubing thereby pressing the seal 12 against the inner surface of the production tubing.

It should be noted that the arm could be formed in many different ways. For example, a hydraulic piston could also be imagined. In addition, it could be imagined that another form of support than a wheel 25 could be used to better spread the force on the inner surface of the pipe. This could be important in pipes which do not have high strength or which are highly corroded.

Figures 6 and 7 show how the device moves inside the production tubing when the mechanical arm extends and pushes the seal against the inner surface of the production tubing. Figure 6 shows the device before the arm extends. As can be seen the wheels 13 push against the inside of the production tubing and keep the seal from coming into contact with the production tubing. Figure 7 shows the arm extended and the device displaced out towards the inner surface of the production tubing opposite the arm thereby compressing the seal against the inner surface of the production tubing. In this way, a well defined closed volume is created between the device and the inner surface of the production tubing. This closed volume can then be filled with epoxy under pressure, thereby forcing the epoxy through the hole in the production tubing and out into the annulus between the production tubing and the casing.

Figure 8 shows a second embodiment 30 of a hole sealing device. The device of figure 8 is in general very similar to the device of figures 4-7 and the same reference numerals will therefore be used to describe the same features. However, the difference lies in the mechanism 31 to press the device against the inner surface of the production tubing. In this case, the mechanism comprises a two arm linkage 32,33, where one end of each arm is connected to a threaded nut 34,35 arranged on oppo- site ends of a threaded rod 36. The threaded rod is furthermore arranged such that one side 36' of the rod has a thread which is opposite to the other side of the rod 36". In this way, when the threaded rod is rotated by the motor 19, the two threaded nuts will either move towards each other or away from each other depending on the direction of rotation of the threaded rod. As in the previous embodiment, a wheel 25 is mounted to the two arm linkage at the joint between the arms 32,33. When the threaded nuts move towards each other, the wheel 25 is moved out of the housing, thereby pressing the seal 12 against the inner surface of the production tubing. When the threaded nuts move away from each other, the wheel is moved into the body and the seal releases the inner surface.

One embodiment of the method according to the information will now be described.

After establishing the approximate depth of the hole/s, the hole sealing device 10 will be mounted below a manipulation tool (not shown) & run on an electric wireline. The manipulation tool could be of the kind shown in WO 01/38689 A1. While the device is moving through the production tubing string, the spring activated wheels 13 or pads arranged on the device will protect the seal element 12 of the device from wear.

Once the device has reached the appropriate depth, the manipulation tool will anchor & rotate the hole sealing device through 360°. A sensor on the hole sealing device could be used to detect the orientation of the hole 7 in order to allow the hole sealing device to be rotated into the correct orientation. Alternatively, a series of pressure tests could be performed at different orientations. When the seal element 12 of the device is facing the hole, the motor 19 in the hole sealing device will work to deploy a mechanical arm mechanism 17. This will in turn push the device against the wall of the production opposite the mechanical arm, compressing the seal element & 'framing' the hole/s in the tubular.

To test that the tool is accurately positioned over a hole, a leak test can be performed by pumping a small volume of gas or fluid, for example N2, into the hole & observing the pressure response in the enclosed volume framed by the seal and/or at the surface. Once the leak path is confirmed, epoxy resin will be injected through the hole/s in the production tubing with a sufficient volume to touch & bond to the inner wall of the next casing, but with an insufficient volume to completely seal off the annulus between the production tubing and the casing. As mentioned previously, if it is desired to completely seal off the annulus, then an increased amount of epoxy is injected into the hole. The properties of the resin (setting time, viscosity, density, tri-axial strength etc) of the resin will be tailored to the individual well. A thin foil liner 9 will be employed on the surface of the tool body to prevent the epoxy bonding to the tool.

Once the epoxy repair is in place, the motor will work to retract the mechanical arm mechanism 17 into the body of the tool, allowing the spring activated wheels 13 or pads to protrude and to protect the seal while the device is being pulled out of the production tubing. In the case where a foil 9 had been used, the foil is released from the device and remains in the well bore, bonded to the epoxy repair.

The procedure is repeated until all the holes in the tubing have been repaired. It is to be noted that it is expected that the best procedure is to remove the device from the well between each hole repair. However, it could also be imagined that a device could be built in accordance with the current invention which could fill more than one hole at a time without being removed from the well.

The 2-part epoxy injection system is not described in detail in this specification since a detailed description of the chemistry of the epoxy system is not essential in order to understand the current invention. However, more information on suitable epoxy systems can be found by consulting relevant patent and non-patent literature or by consulting an expert in the field. The advantage of using an epoxy system is due to the fact that the chemistry of epoxy resins allows them to be produced with a very broad range of properties. Properties such as setting time, viscosity, density & tri- axial strength can all be tailored to each specific job. Also, different additives, for example strengthening fibres, could be added to the epoxy in order to optimize its properties.

It should be noted that due to the relatively small size of the resulting epoxy patch between the production tubing and the casing, the patch will not impede removal of the production tubing after the patch is established. However, in certain cases, for example if large holes have been filled or if there a large number of filled holes, the epoxy could impede removal of the tubing. In this case, it is envisaged that the epoxy plug/patch could be removed from the well bore with the application of sufficient heat, which could potentially be necessary as part of the well abandonment. It is imagined that other techniques could also be used to remove the epoxy if this was required.

It is also to be noted that the above description has focused on production tubing as an example of pipe in pipe tubing. The current invention can however also be used together with other forms of pipe in tubing. For example an intermediate casing string,

It is also to be noted that the above description has only focused on epoxy as the sealant material. However, other forms of sealant materials could be used within the context of this specification. For example, many different forms of elastomeric materials could be used, for example phenolic resins and rubber/self vulcanizing rubber. As another example, metal based sealants could also be used, for example molten lead or tin.

It is to be noted that the figures and the above description have shown the example embodiments in a simple and schematic manner. The internal electronic and mechanical details have not been shown since the person skilled in the art should be familiar with these details and they would just unnecessarily complicate this description.

Claims

1. A method for the in-situ repair of holes (7) in pipe in pipe tubulars (5), said method comprising the following steps:

- running a hole sealing device (10) into the pipe in pipe tubular (5), - identifying the hole (7) in the pipe in pipe tubular, and

- injecting a sealant material (8) into the hole via the hole sealing device.

2. A method according to claim 1 , characterized in that the sealant material (8) used is a two component epoxy.

3. A method according to claim 1 or 2, characterized in that the method further comprises the step of rotating the hole sealing device (10) in the pipe in pipe tubular (5) until a sealant material injecting nozzle (15) of the hole sealing device faces the hole (7) in the pipe in pipe tubular.

4. A method according to claim 1 , 2 or 3, characterized in that the method further comprises the step of pressing the hole sealing device (10) against the inner surface of the production tubing (5) such that a seal (12) is established around the hole (7).

5. A method according to any one of claims 1-4, characterized in that the step of injecting a sealant material (8) into the hole (7) , injects enough sealant material to partially fill the annulus (6) between the production tubing (5) and the casing (2).

6. A method according to any one of claims 1-5, characterized in that a thin foil or a non-stick material (9) is arranged between the inner surface of the production tubing (5) and the device (10) before the sealant material (8) is injected into the hole (7).

7. A device (10;30) suitable for the method according to any one of claims 1-6, characterized in that the device comprises an elongated seal (12) having a longitudinal axis which is parallel with the longitudinal axis of the production tubing (5) and which is arranged to establish a seal around an area of the in- ner surface of the production tubing when the device is pressed against the inner surface of the production tubing.

8. A device (10;30) suitable for the method according to any one of claims 1-6, characterized in that the device comprises means for holding a foil (9) between the sealant (8) and the device, such that sealant does not fasten the device to the inner surface of the production tubing (5).

9. A device (10;30) according to claim 7 or 8, characterized in that the device comprises a mechanism with a mechanical arm (17; 31 ) which is arranged to press the device against the inner surface of the production tubing (5) opposite the mechanical arm.

10. A device (10;30) according to claim 9, characterized in that the mechanism comprises a threaded rod (18; 36), a threaded nut (21 ;34,35) arranged on the threaded rod and an arm (22;32,33) attached to the threaded nut, where rotation of the threaded rod causes the arm attached to the threaded nut to extend from the housing.