NO348253B1

NO348253B1 - Well tool device

Info

Publication number: NO348253B1
Application number: NO20230009A
Authority: NO
Inventors: Petter Thorrud Larsen
Original assignee: Interwell Norway As
Priority date: 2023-01-06
Filing date: 2023-01-06
Publication date: 2024-10-28
Also published as: NO20230009A1; WO2024146769A1

Description

FIELD OF THE INVENTION

The present invention relates to a well tool device.

BACKGROUND OF THE INVENTION

Many well tools, such as well plugs (bridge plugs, packers, etc.) comprise a sealing device and an anchor device connected to a mandrel. The plug has a radially retracted, or run, state and a radially expanded, or set, state. In the set state, the anchoring device is in contact with the inner surface of the well pipe, and prevents the plugging device from moving axially within the well pipe. In the set state, the sealing device is sealing off the annular space between the mandrel of the plug and the inner surface of the well pipe in order to prevent fluid flow between the lower side of the sealing element and the upper side of the sealing element.

The sealing device comprises a sealing element designed to retract and expand between its run and set states and must also be designed to withstand a high pressure difference and also be able to seal the annular area at high temperatures. In order to do so, the sealing element, typically made from an elastomer, a rubber material etc., must be supported by supporting devices in the set state.

One such plug is shown in US 7178602. Here, the sealing device comprises a sealing element and supporting devices on its upper and lower sides. Each supporting device comprises a number of first supporting arms and a number of second supporting arms having their first ends pivotably connected to a supporting ring provided around the mandrel and where their second ends are pivotably connected to each other. This principle is used in the commercially available High Expansion Retrievable Bridge plug (HEX plug), sold and marketed by Interwell (https://www.interwell.com/high-expansion-retrievable-bridgeplug/category601.html).

One of the HEX plugs are made for use in a 7" 29 pounds/feet well pipes, where the specification for such pipes allows the inner diameter of the pipe to vary in a range between ca 154.6 – 159.8 mm, i.e. a variation in the distance between the outside of the supporting arms of the plug in its set state to the inner surface of the well pipe up to 3 mm. The supporting devices cannot be made to expand to the largest possible diameters of these pipes, because when set in a narrower pipe, the supporting devices will contact the pipe surface before a sufficient compression of the sealing element has been achieved.

NO 341581 describes a variant of the HEX plug which solves the above problem, by allowing the proximal supporting element to be displaced at a radial distance (d) from the first set state to a second set state. Hence, if the inner diameter of the well pipe allows it, a further increase of the outer diameter of the supporting device is allowed. This principle is used in the commercially available High Temperature High Expansion Bridge plug (THEX plug), sold and marketed by Interwell (https://www.interwell.com/high-temperature-high-expansion-bridgeplug/category728.html).

WO 2012/079913 and WO 2012/079914 describes a plugging device, comprising a packer device for pressure tight sealing of a pipe. The packer device comprises a cone device comprising a first cone and a second cone, each having their base faced towards each other and each comprising a tapering surface. A first packer supporting device is provided on a first side of the cone device, a second packer supporting device is provided on a second side of the cone device and a packer body is provided between the first packer supporting device and the second packer supporting device. The first and second packer supporting devices comprise supporting arms having a first end movably connected to the plugging device and a second end connected to either a front supporting element or a rear supporting element. A sliding surface is provided on the first and second packer supporting device for sliding up and down the tapering surface of the first or second cone, thereby bringing the packer device between its expanded and retracted position respectively. The front supporting elements and the rear supporting elements comprise front surfaces, where the front surfaces are faced towards the base of the first and second cones and provide an extrusion barrier surface for the packer body in the expanded position.

The object of the present invention is to provide a well tool device with a sealing device which can be used to seal a well pipe at a desired location, and where the well pipe has a narrow restriction at a location above the desired location .

SUMMARY OF THE INVENTION

The present invention relates to a well tool device for forming a seal in a well, wherein the well tool device is comprising:

- a mandrel defining a longitudinal center axis of the well tool device;

- a sealing device located concentric outside of the mandrel;

wherein the sealing device comprises a first sealing section and a second sealing section;

wherein the first sealing section comprises first sealing elements;

wherein the second sealing section comprises second sealing elements; wherein the sealing device is configured to be in a radially retracted state, in which the first and second sealing elements are pivoted to their retracted position; wherein the sealing device is configured to be in a radially expanded state, in which the first and second sealing elements are pivoted to their expanded position; wherein, in the radially retracted state, the first sealing section is longitudinally separated from the second sealing section;

wherein the first sealing section comprises a proximal supporting ring being proximal to the second sealing section, wherein the first sealing elements are pivotably connected to the proximal supporting ring;

wherein the second sealing section comprises a proximal supporting ring being proximal to the first sealing section, wherein the second sealing elements are pivotably connected to the proximal supporting ring;

wherein, when in the radially expanded state, the seal is formed by alternating first sealing elements and second sealing elements around a circumference of the well tool device, thereby providing that each of the first sealing elements has two neighbouring second sealing elements and each of the second sealing elements has two neighbouring first sealing elements.

In one aspect, each sealing element is sealingly engaged with its two neighbouring sealing elements.

In one aspect, each first sealing element comprises a front surface facing in a radially outward direction in the radially retracted state and facing towards the second sealing section in the radially expanded state; wherein each second sealing element comprises a front surface facing in the radially outward direction in the radially retracted state and facing towards the first sealing section in the radially expanded state.

In one aspect, the front surface of each first and second sealing element is encompassed by an inner edge, an outer edge and two side edges between the inner edge and the outer edge.

In one aspect, the front surface is wedge-shaped.

In one aspect, the inner edge is closer to the longitudinal center axis in the radially expanded state than the outer edge. Hence, the inner edge is considered to be radially inside of the outer edge.

In one aspect, each side edges comprises a flange protruding from the front surface, wherein each flange is brought into contact with the front surface of the neighbouring sealing element in the radially expanded state.

In one aspect, the flanges of two neighbouring sealing elements together with an area of each front surface are forming a radial compartment in the radially expanded state.

In one aspect, the front surface is partially overlapped by its neighbouring sealing element in the radially retracted state.

In one aspect, the front surface is curved relative to the outer diameter of the well tool device when seen in the radially retracted state.

In one aspect, a central line of the front surface is substantially parallel with the central longitudinal axis in the radially retracted state.

In one aspect, the side edges are oriented in a radial direction in the radially expanded state.

In one aspect, each side edge of each of the first sealing elements is sealingly engaged with one of the side edges of the second sealing element in the radially expanded state.

In one aspect, the outer edges of the first and second sealing elements are facing in a radially outward direction in the radially expanded state.

In one aspect, the outer edges of the first and second sealing elements form a continuous surface or path along the circumference of the sealing device in the radially expanded state.

In one aspect, the outer edges are configured to sealingly engage an inner surface of the well.

In one aspect, the continuous path is substantially circular.

In one aspect, the continuous path has an outer diameter which is substantially equal to the inner diameter of the well.

In one aspect, the sealing device comprises an elastomeric material applied to the inner edge and/or the outer edge and the two side edges of each sealing element.

In one aspect, the inner edge is sealingly engaged with its proximal supporting ring in the radially expanded state.

In one aspect, the inner edge is sealingly engaged with the proximal supporting ring of the other one of the sealing sections.

In one aspect, the elastomeric material is applied to the sealing elements by means of a vulcanization process.

In one aspect, the first sealing section comprises a distal supporting ring being distal to the second sealing section and supporting arms having a first end and a second end, wherein the first end of each supporting arm is pivotably connected to the distal supporting ring and wherein the second end of each supporting arm is pivotably connected to one of the first sealing elements;

wherein the second sealing section comprises a distal supporting ring being distal to the first sealing section and supporting arms having a first end and a second end, wherein the first end of each supporting arm is pivotably connected to the distal supporting ring and wherein the second end of each supporting arm is pivotably connected to one of the second sealing elements;

wherein the sealing device is brought from its radially retracted state to its radially expanded state by relative movement of the distal supporting rings and the proximal supporting rings in a direction towards each other.

In one aspect, the sealing device is brought from its radially expanded state to its radially retracted state by relative movement of the distal supporting rings and the proximal supporting rings in a direction away from each other.

In one aspect, each sealing element comprises a rear surface opposite of the front surface, wherein the second end of each supporting arm is pivotably connected to the rear surface of one of the sealing elements.

In one aspect, the first sealing section is identical to the second sealing section. The first sealing section is inserted onto the mandrel device in the opposite way as the second sealing device, thereby achieving that their proximal supporting rings are adjacent to each other. The first sealing section is rotated on the mandrel device relative to the second sealing device, thereby achieving that each second sealing element becomes positioned between two first sealing elements and that each first sealing element becomes positioned between two second sealing elements in the set state.

As used herein, the terms “radially retracted state” and “run state” are used interchangeably for the state in which the well tool device is lowered into a desired location in the well. The terms “radially expanded state” and “set state” are used interchangeably for the state in which the well tool device performs its sealing function at the desired location in the well. As is commonly known, the function of a seal of a well tool device is to prevent or reduce axial fluid flow at the desired location in the well, i.e. to prevent or reduce fluid from flowing between a location above the well tool device and a location below the well tool device. It is further commonly known that the sealing device is only capable of forming a seal when the well tool device is brought to its radially expanded state in the well. The best sealing effect is achieved if/when the sealing device is expanded into contact with the inner surface of the well. Finally, it should be noted that well tool devices are rated to a pressure level or pressure interval and/or a temperature level or temperature interval.

The terms “upper”, “above”, “below” and “lower” are used herein to define parts of the well tool device, when the well tool device is used in a well. “Upper” and “above” refer to a position relatively closer to the well opening and “below“ and “lower” refer to a position relatively further away from the well opening. These terms apply both when the well has a vertical and horizontal orientation.

According to the above, it is achieved a well tool device with increased ratio between the outer diameter in the set state and the outer diameter in the run state.

The well tool device is specifically designed for the purpose of creating a barrier between a water producing zone and an oil producing zone in an oil well. Hence, it is achieved that a cementing operation can be avoided. As is known, it takes time for cement to harden, and a milling operation must be performed for removal of the barrier. In addition, a cementing operation will not work in a horizontal well.

DETAILED DESCRIPTION

Embodiments of the invention will now be described in detail with reference to the enclosed drawings, wherein:

Fig. 1 shows a perspective view of a sealing device of the well plugging device in its run state;

Fig. 2 shows a perspective view of the sealing device in fig. 1 in its set state;

Fig. 3 shows a cross sectional view of the sealing device in fig. 1 in its run state; Fig. 4 shows a cross sectional view of the sealing device in fig. 3 in its set state; Fig. 5 shows a perspective view of one half-section of the sealing device in fig. 1 in its run state;

Fig. 6 shows a perspective view of the one half-section of the sealing device in fig.

5 in its set state;

Fig. 7 shows a side view of the sealing device in its set state;

Fig. 8 shows an enlarged view of the dashed box A of fig. 7;

Fig. 9 shows a perspective view of the first/second sealing device in the set state, where an elastomeric material is applied to one of the sealing elements;

Fig. 10 shows a side view of the radial expansion of the sealing elements in the radially expanded state.

It is now referred to fig. 1 and fig. 2. Here it is shown a well tool device 1 comprising a mandrel 10 defining a longitudinal center axis CDA of the well tool device 1 and a sealing device 20 located concentric outside of the mandrel 10. Fig. 1 shows the well tool device 1 in a run state while fig. 2 shows the well tool device 1 in a set state.

In addition, the well tool device 1 may comprise a connection interface (not shown) for connection to a setting tool (not shown), for the purpose of bringing the well tool device 1 from its run state to its set state and possibly also from its set state to its retrieval state. In the present embodiment, the retrieval state is substantially equal to the run state. Here, it should be noted that a shear pin is typically used to prevent the device 1 from going to the set state to early. This shear pin is sheared off by the setting tool at the desired location in the well. Hence, in the retrieval state, this shear pin is of course still sheared off. The setting tool will keep the well tool device 1 in its retrieval state when pulling the tool out from the well.

The well tool device 1 may further comprise an anchoring device (not shown) for the purpose of preventing longitudinal movement of the well tool device 1 when set in the well. It should be noted that the connection interface and the anchoring device may be of the type well known from for example the above THEX plug. Similarly, the setting tool may be a tool similar to the Interwell Electronic Setting Tool (EST).

Below, the sealing device 20 will be described further in detail.

The sealing device 20 comprises a first sealing section 30 and a second sealing section 40.

The first sealing section

It is now referred to fig. 5 and fig. 6. The first sealing section 30 comprises a proximal supporting ring 33 being proximal to the second sealing section 40, sealing elements 31 pivotably connected to the proximal supporting ring 33, a distal supporting ring 34 being distal to the second sealing section 40 and supporting arms 32 having a first end and a second end, wherein the first end of each supporting arm 32 is pivotably connected to the distal supporting ring 34 and wherein the second end of each supporting arm 32 is pivotably connected to one of the first sealing elements 31.

The first sealing section can be brought from its run state of fig. 5 to its set state of fig. 6 by decreasing the distance between the proximal supporting ring 33 and the distal supporting ring 34.

The proximal supporting ring 33 comprises a number of recesses 33r in which a spherical element of the first sealing element 31 can be inserted and pivoted relative to. A spherical element 43spe of the second sealing element 41 is shown in fig. 4. It is further shown that the proximal supporting ring 33 comprises an inclining surface 33is between each of the recesses. This inclining surface 33is is also shown in fig.

10.

One of the first sealing elements 31 will now be described with reference to fig. 5, 6 and 7. It should be noted that in the present embodiment, the first sealing elements 31 are identical to each other.

The first sealing element 31 comprises a front surface 31f and a rear surface 31r on the opposite side of the front surface 31f. As shown in fig. 7, a connector 31c is provided on the rear surface 31r. The connector 31c is pivotably connected to the arm 32.

The front surface 31f is encompassed by an inner edge 31n, an outer edge 31w and two side edges 31s between the inner edge 31n and the outer edge 31w. The names of the edges and surfaces are here chosen based on set state. The front surface 31f is facing towards the second sealing section 40 in the set state. The inner edge 31n is closer to the longitudinal centre axis CDA than the outer edge 31w in the set state and the inner edge is hence located inside of the outer edge in the set state.

As shown in fig. 6, the outer edge 31w is longer than the inner edge 31n. Hence, when seen as shown in fig. 6, the front surface 31f can be considered to be wedgeshaped. Here it is also shown that the side edges 31s are oriented in a radial direction RD in the set state.

In the run state, a central line L31s along the centre of the front surface 31f is substantially parallel with the central longitudinal axis CLA. Hence, a line perpendicular to this central line L31s will be oriented in the radial direction RD as indicated in fig. 3.

Moreover, the front surface 31f is curved relative to the outer diameter OD1 of the well tool device 1 when seen in the run state, see for example fig. 3, fig. 5. In fig. 3, the substantially circular curve C31 is indicating the cylindrical shape of the sealing elements 31 when in the run state. Here it is also shown that the front surface 31f of each first sealing element 31 is partially overlapped by its neighbouring first sealing element 41 in the run state.

In fig. 6 and fig. 8, it is further shown that each side edge 31s comprises a flange 31pf protruding from the front surface 31f.

The second sealing section

In the present embodiment, the first sealing section 30 is identical to the second sealing section 40. Both sealing sections 30, 40 comprises six sealing elements. Hence, in fig. 5 and fig. 6, reference numbers for both the first sealing section 30 and the second sealing section 40 are indicated.

It is now referred to fig. 5 and fig. 6. The second sealing section 40 comprises a proximal supporting ring 43 being proximal to the first sealing section 30, sealing elements 41 pivotably connected to the proximal supporting ring 43, a distal supporting ring 44 being distal to the first sealing section 40 and supporting arms 42 having a first end and a second end, wherein the first end of each supporting arm 42 is pivotably connected to the distal supporting ring 44 and wherein the second end of each supporting arm 42 is pivotably connected to one of the second sealing elements 41.

The second sealing section can be brought from its run state of fig. 5 to its set state of fig. 6 by decreasing the distance between the proximal supporting ring 43 and the distal supporting ring 44.

The proximal supporting ring 43 comprises a number of recesses 43r in which a spherical element of the second sealing element 41 can be inserted and pivoted relative to. A spherical element 43spe of the second sealing element 41 is shown in fig. 4. It is further shown that the proximal supporting ring 43 comprises an inclining surface 43is between each of the recesses. This inclining surface 43is is also shown in fig. 10.

One of the second sealing elements 41 will now be described with reference to fig.

5, 6 and 7. It should be noted that in the present embodiment, the second sealing elements 41 are identical to each other.

The second sealing element 41 comprises a front surface 41f and a rear surface 41r on the opposite side of the front surface 41f. As shown in fig. 7, a connector 41c is provided on the rear surface 41r. The connector 41c is pivotably connected to the arm 42.

The front surface 41f is encompassed by an inner edge 41n, an outer edge 41w and two side edges 41s between the inner edge 41n and the outer edge 41w. The names of the edges and surfaces are here chosen based on set state. The front surface 41f is facing towards the second sealing section 40 in the set state. The inner edge 41n is closer to the longitudinal centre axis CDA than the outer edge 41w in the set state and the inner edge is hence located inside of the outer edge in the set state.

As shown in fig. 6, the outer edge 41w is longer than the inner edge 41n. Hence, when seen as shown in fig. 6, the front surface 41f can be considered to be wedgeshaped. Here it is also shown that the side edges 41s are oriented in a radial direction RD in the set state.

In the run state, a central line L41s along the centre of the front surface 41f is substantially parallel with the central longitudinal axis CLA. Hence, a line perpendicular to this central line L41s will be oriented in the radial direction RD as indicated in fig. 3.

Moreover, the front surface 41f is curved relative to the outer diameter OD1 of the well tool device 1 when seen in the run state, see for example fig. 3, fig. 5. In fig. 3, the substantially circular curve C41 is indicating the cylindrical shape of the sealing elements 41 when in the run state. Here it is also shown that the front surface 41f of each second sealing element 41 is partially overlapped by its neighbouring second sealing element 41 in the run state.

In fig. 6 and fig. 8, it is further shown that each side edge 41s comprises a flange 41pf protruding from the front surface 41f.

Operation of the well tool device

The well tool device and its operation will now be described. Initially, it should be noted that the purpose of the well tool device 1 is to form a seal S in a well W (see fig. 7), between a water producing zone of the well and an oil producing zone of the well. It should further be noted that the pressure difference between these two zones is zero or close to zero, and hence that the purpose is to separate water from oil to prevent or at least considerably reduce water production from the well.

The outer diameter OD1 in the run state indicated in fig. 3 is 2.5 inches. Here, the first and second sealing elements 31, 41 of the sealing device 20 are pivoted to their retracted position.

In fig. 3 it is further shown that the first sealing section 30 is longitudinally separated from the second sealing section 40. Line SP indicates the separation plane separating the first sealing section 30 from the second sealing section 40. It should be noted that the proximal supporting ring 33 may be in contact with the proximal supporting ring 43 in the run state.

When the well tool device 1 is arriving at the desired location in the well, the setting tool is bringing the device 1 to its set state, as indicated in fig. 4. Here, the outer diameter OD is ca 7.0 inches. Here, the first and second sealing elements 31, 41 of the sealing device 20 are pivoted to their expanded position.

It is now referring to fig. 6. Here it is shown that when the sealing elements of one of the sealing sections are pivoted to their expanded position, there is a gap G between each sealing element. As there is six sealing elements, there is also six gaps. These gaps G are sealed by the sealing elements of the other one of the sealing sections, as shown in fig. 2 and fig. 7.

It is now referred to fig. 7 and fig. 8. Here it is shown that each first sealing element 31 is sealingly engaged with its two neighbouring second sealing elements 41.

Similarly, each second sealing element 41 is sealingly engaged with its two neighbouring first sealing elements 31. In this way, a seal S is formed.

In fig. 7 and 8, it is shown that the flange 31pf of the first sealing element 31 is brought into contact with the front surface 41f of the neighbouring second sealing element 41. Similarly, the flange 41pf of the second sealing element 41 is brought into contact with the front surface 31f of the neighbouring first sealing element 31. It is further shown that there is a distance between these two flanges 31pf, 41pf.

Hence the flanges 31pf, 41pf together with an area of each front surface 31f, 41f are forming a radial compartment 22.

Preferably, the sealing device 20 comprises an elastomeric material 22 applied to the inner edge 31n, 41n, the outer edge 31w, 41w and the two side edges 31s, 41s of each sealing element 31, 41. This is indicated as a solid line 22 on one of the sealing elements of fig. 9. The elastomeric material 22 may be applied to the sealing elements by means of a vulcanization process.

Hence, the compartment 22 may be at least partially filled with an elastomeric material 23 in the set state.

As shown in fig. 7, the outer edges 31w, 41w of the first and second sealing elements 31, 41 form a continuous surface or path along the circumference of the sealing device 20 in the set state, as indicated by a dashed line CP in fig. 7. Also this continuous surface CP will be provided by the elastomeric material 22, as each outer edge 31w, 41w has such an elastomeric material 22. The continuous surface CP will typically be brought into contact with the inner surface of the well W.

As indicated in fig. 7, the continuous path CP will have the shape of a wavy circle having an outer diameter OD2 which is substantially equal to the inner diameter IDW of the well W.

The inner edges 31n, 41n are sealingly engaged with its proximal supporting ring 33, 43 or with the proximal supporting ring 43, 33 of the other one of the sealing sections 40, 30. Also here, the elastomeric material 22 may improve the sealing between proximal supporting rings and the sealing elements.

According to the above, the sealing element 20 is forming a continuous seal around the circumference of the mandrel device 10 in the radially expanded state, wherein every second sealing element is one of the first sealing elements and every second sealing element is one of the second sealing elements.

It is now referred to fig. 10. Here it is shown that the inclining surface 33is, 43is is of the proximal supporting ring 33, 43 is engaged with a corresponding inclining surface 31is, 43is on the rear side 31r, 41r of each sealing element 31, 41. During the setting operation, each sealing element 31, 41 may be pressed radially outwardly a distance DR towards the inner surface of the well, as long as the inner surface of the well allows it. Hence, a sealing engagement may be achieved even if there are small variations in the inner diameter of the well.

It should be noted that a measurement tool, such as a multifinger caliper log tool, may be used before lowering the well tool device 1 into the well, to measure the inner diameter of the well and/or to detect deformations in the inner surface of the well. Hence, it can be avoided that the well tool device 1 is set in an area of the well is unfavourable, i.e. an area where it is not possible to achieve a sealing engagement between the sealing device 20 and the well.

Claims

1. A well tool device (1) for forming a seal (S) in a well (W), wherein the well tool device (1) is comprising:

- a mandrel (10) defining a longitudinal center axis (CDA) of the well tool device (1);

- a sealing device (20) located concentric outside of the mandrel (10);

wherein the sealing device (20) comprises a first sealing section (30) and a second sealing section (40);

wherein the first sealing section (30) comprises first sealing elements (31); wherein the second sealing section (40) comprises second sealing elements (41); wherein the sealing device (20) is configured to be in a radially retracted state, in which the first and second sealing elements (31, 41) are pivoted to their retracted position;

wherein the sealing device (20) is configured to be in a radially expanded state, in which the first and second sealing elements (31, 41) are pivoted to their expanded position; characterized in that:

in the radially retracted state, the first sealing section (30) is longitudinally separated from the second sealing section (40);

wherein the first sealing section (30) comprises a proximal supporting ring (33) being proximal to the second sealing section (40), wherein the first sealing elements (31) are pivotably connected to the proximal supporting ring (33);

wherein the second sealing section (40) comprises a proximal supporting ring (43) being proximal to the first sealing section (30), wherein the second sealing elements (41) are pivotably connected to the proximal supporting ring (43);

wherein, when in the radially expanded state, the seal (S) is formed by alternating first sealing elements (31) and second sealing elements (41) around a circumference (CF) of the well tool device, thereby providing that each of the first sealing elements (31) has two neighbouring second sealing elements (41) and each of the second sealing elements (41) has two neighbouring first sealing elements (31).

2. The well tool device (1) according to claim 1, wherein each sealing element (31, 41) is sealingly engaged with its two neighbouring sealing elements (41, 31).

3. The well tool device (1) according to claim 1 or 2, wherein each first sealing element (31) comprises a front surface (31f) facing in a radially outward direction (ROD) in the radially retracted state and facing towards the second sealing section (40) in the radially expanded state; wherein each second sealing element (41) comprises a front surface (41f) facing in the radially outward direction (ROD) in the radially retracted state and facing towards the first sealing section (30) in the radially expanded state.

4. The well tool device (1) according to claim 3, wherein the front surface (31f, 41f) of each first and second sealing element (31, 41) is encompassed by an inner edge (31n, 41n), an outer edge (31w, 41w) and two side edges (31s, 41s) between the inner edge (31n, 41n) and the outer edge (31w, 41w).

5. The well tool device (1) according to claim 4, wherein each side edges (31s, 41s) comprises a flange (31pf, 41pf) protruding from the front surface (31f, 41f), wherein each flange (31pf, 41pf) is brought into contact with the front surface (31f, 41f) of the neighbouring sealing element (31, 41) in the radially expanded state.

6. The well tool device (1) according to claim 5, wherein the flanges (31pf, 41pf) of two neighbouring sealing elements (31, 41) together with an area of each front surface (31f, 41f) are forming a radial compartment (22) in the radially expanded state.

7. The well tool device (1) according to any one of claims 3 - 6, wherein the front surface (31f, 41f) is partially overlapped by its neighbouring sealing element (41, 31) in the radially retracted state.

8. The well tool device (1) according to any one of claims 3 - 7, wherein the front surface (31f, 41f) is curved relative to the outer diameter (OD1) of the well tool device (1) when seen in the radially retracted state.

9. The well tool device (1) according to any one of claims 4 - 8, wherein the side edges (31s, 41s) are oriented in a radial direction (RD) in the radially expanded state.

10. The well tool device (1) according to any one of claims 4 - 9, wherein each side edge (31s) of each of the first sealing elements (31) is sealingly engaged with one of the side edges (41s) of the second sealing element (41) in the radially expanded state.

11. The well tool device (1) according to any one of the above claims 4 - 10, wherein the outer edges (31w, 41w) of the first and second sealing elements (31, 41) are facing in a radially outward direction (RD) in the radially expanded state.

12. The well tool device (1) according to claim 11, wherein the outer edges (31w, 41w) of the first and second sealing elements (31, 41) form a continuous surface or path (CP) along the circumference of the sealing device (20) in the radially expanded state.

13. The well tool device (1) according to claim 12, wherein the continuous path (CP) has an outer diameter (OD2) which is substantially equal to the inner diameter (IDW) of the well (W).

14. The well tool device (1) according to any one of claims 4 - 13, wherein the sealing device (20) comprises an elastomeric material (23) applied to the inner edge (31n, 41n) and/or the outer edge (31w, 41w) and the two side edges (31s, 41s) of each sealing element (31, 41).

15. The well tool device (1) according to any one of the above claims, wherein the first sealing section (30) comprises a distal supporting ring (34) being distal to the second sealing section (40) and supporting arms (32) having a first end and a second end, wherein the first end of each supporting arm (32) is pivotably connected to the distal supporting ring (34) and wherein the second end of each supporting arm (32) is pivotably connected to one of the first sealing elements (31); wherein the second sealing section (40) comprises a distal supporting ring (44) being distal to the first sealing section (30) and supporting arms (42) having a first end and a second end, wherein the first end of each supporting arm (32) is pivotably connected to the distal supporting ring (44) and wherein the second end of each supporting arm (32) is pivotably connected to one of the second sealing elements (41);

wherein the sealing device (20) is brought from its radially retracted state to its radially expanded state by relative movement of the distal supporting rings (34, 44) and the proximal supporting rings (33, 43) in a direction towards each other.

16. The well tool device (1) according to claim 15, wherein each sealing element (31, 41) comprises a rear surface (31r, 41r) opposite of the front surface (31f, 41f), wherein the second end of each supporting arm (32, 42) is pivotably connected to the rear surface (31r, 41r) of one of the sealing elements (31, 41).

17. The well tool device (1) according to any one of the above claims, wherein the first sealing section (30) is identical to the second sealing section (40).