NL2016868B1

NL2016868B1 - Device for moving a first conduit section relative to a second conduit section

Info

Publication number: NL2016868B1
Application number: NL2016868A
Authority: NL
Inventors: Boerhof Henk; Veenstra Feitze
Original assignee: Callidus Capital B V
Priority date: 2016-05-31
Filing date: 2016-05-31
Publication date: 2017-12-11
Also published as: DK3464735T3; EP3464735A1; WO2017209608A1; EP3464735B1

Abstract

The various aspects relate to moving a first conduit section of a conduit relative to a second conduit section of the conduit. The device comprises end sections comprising fixation modules. The fixation modules are arranged for fixating the ends sections to the applicable conduit sections. The device also comprises a middle section provided between the first and the second end section. The middle section comprises a linear actuator module for moving the middle section relative to at least one of the first end section and the second end section. This device is suitable for validating of cutting of the bumper piles or other conduits. Cutting tools currently used for cutting such conduits are not perfect and may leave material connecting the first conduit section and the second conduit section. By moving the first section away from the second section, one is sure both sections are well separated.

Description

P111292NL00

Title: Device for moving a first conduit section relative to a second conduit section

TECHNICAL FIELD

The various aspects and embodiments thereof relate to a device for moving a first section of an elongated member relative to a second section of an elongated member. Some embodiments relate to separation of a first part of a hollow foundation member from a second part of a hollow foundation member.

BACKGROUND

With depletion of subsea oil and gas fields as well as the advent of new drilling techniques, certain platforms for exploration and exploitation of these oil and gas field become obsolete. Therefore, they may need to be removed. On continental shelves, such platforms are built on elongated bumper piles. Such bumper piles may be hollow, preferably cylindrical, conduits, for example made from steel. Once the drilling platform is removed, the piles have to be removed. In accordance with current and expected future legislation, the piles have to be removed at least such that no structure are left above the seabed.

SUMMARY

Hence, a device for removing at least a part of the foundation piles that are above or possibly just below the seabed. This may require separation of sections of such piles. A first aspect provides a device for moving a first conduit section of a conduit relative to a second conduit section of the conduit. The device comprises a first end section comprising a first fixation module for fixating the first end section to an inner wall of the first conduit section for inhibiting movement of the first end section relative to the first conduit section and a second end section comprising a second fixation module for fixating the second end section to an inner wall of the second conduit section for inhibiting movement of the second end section relative to the second conduit section. The device also comprises a middle section provided between the first end section and the second end section, the middle section comprising a linear actuator module for moving the middle section relative to at least one of the first end section and the second end section.

This device is suitable for validating of cutting of the bumper piles or other conduits. Cutting tools currently used for cutting such conduits are not perfect and may leave material connecting the first conduit section and the second conduit section. Validation of the cut using conventional methods is not perfect, either. By moving the first section away from the second section, one is sure both sections are well separated.

In an embodiment, the linear actuator module comprises a force sensor connector for connecting a force sensor in communication with the linear actuator module for sensing a force required for moving the first conduit relative to the second conduit.

By measuring the force required for moving the first conduit section relative to the second conduit section, a force is obtained that is at least required for moving the first conduit section, the second conduit section or both away from their current position. The force required for removal may be determined by the weight of the section, a friction force provided by a medium surrounding the applicable conduit section, a buoyancy force, other, or a combination thereof. Having determined this force, further appropriate tools may be selected and employed for removing the first section, the second section or both.

In another embodiment, the linear actuator module comprises a motion sensor connection for connecting a motion sensor in communication with the linear actuator module for sensing a movement of the first conduit relative to the second conduit.

When sensing movement and linear movement in particular, the a good situation is obtained for determining a force at least required for moving one or both of the section.

In a further embodiment, the first fixation module and the second fixation module are arranged for increasing a cross-section diameter of the first end section and the second end section, respectively.

The fixation modules in accordance with this embodiment provide for robust fixation of the device relative to the conduit. A second aspect provides a method of moving a first conduit section of a conduit relative to a second conduit section of a conduit by means of a device. The method comprises fixating a first end section of the device to an inner wall of the first conduit section for inhibiting movement of the first end section relative to the first conduit section fixating a second end section of the device to an inner wall of the second conduit section for inhibiting movement of the second end section relative to the second conduit section and operating a linear actuator provided between the first end section and the second end section for moving the first end section and the second end section apart from one another. A third aspect provides a method of dividing a conduit into a first conduit section and a second conduit section. The method comprises dividing the conduit in a first conduit section and a second conduit section by cutting the conduit and the method according to the second aspect. A fourth aspect provides a method of determining a force required for lifting a first conduit section comprised by a conduit, the conduit further comprising a second conduit section, the second conduit section being substantially stationary positioned in a medium. The method comprises the method according to the third aspect and determining a force required for moving the first end section and the second end section apart from one another.

BRIEF DESCRIPTION OF THE DRAWINGS

The various aspects and embodiments thereof will now be discussed in further detail in conjunction with drawings. In the drawings:

Figure 1 A: shows a device for moving a first conduit section relative to a second conduit section;

Figure 1 B: shows the device with end sections having enlarged diameters;

Figure 2 A: shows another device for moving a first conduit section relative to a second conduit section;

Figure 2 B: shows the other device with end sections having enlarged diameters;

Figure 2 C: shows a detail of an end section of the device;

Figure 2 D: shows the detail of the end section with enlarged diameter;

Figure 3 A: shows a bumper pile with the device to be descended in the bumper pile;

Figure 3 B: shows the device having cut the bumper pile;

Figure 3 C: shows the device having moved an upper section of the bumper pile upward relative to a lower section of the bumper pile;

Figure 3 D: shows the upper section of the bumper pile lifted above sea-level; and

Figure 4: shows a flowchart.

DETAILED DESCRIPTION

Figure 1 A shows a device 100 comprising a first end section 110, a second end section 120 and a middle section 130. The middle section 130 is rotatably mounted to the first end section 110 over a first bearing 142 and to the second end section 120 over a second bearing 144. The first end section 110 and the second end section 120 may be arranged to rotate relative to one another. In a preferred embodiment, the first end section 110 and the second end section 120 are connected to one another such that they are not rotatable relative to one another.

The middle section 130 comprises a middle body 132. The middle body 132 comprises an electromotor as a mechanical actuator or driving module for rotating the middle section 130 relative to the first end section 110 and the second end section 120. Alternatively, one or move driving modules may be comprised by first end section 110 and/or the second end section 120 for the same purpose. Alternatively of additionally to the electromotor, also other mechanical actuators may be envisaged, such as a hydraulic motor.

The middle body 132 holds a nozzle 136 for ejecting an abrasive slurry under high pressure for cutting plate-like material. The nozzle 136 is connected to a high pressure pump 152 for providing the abrasive slurry from a reservoir 154 to the nozzle 136 under high pressure. In this embodiment, the nozzle 136 is fixedly connected to the middle section 130, allowing the nozzle 136 to rotate with the middle section 130 relative to the first end section 110 and the second end section 120. In another embodiment, the middle section 130 is not rotatable relative to the first end section 110 and the second end section 120. In such embodiment, the nozzle 136 is rotatable over the dash-dotted line 102.

The reservoir 154 may comprise pre-mixed slurry. Alternatively or additionally, the reservoir 154 may comprise multiple compartments for holding a liquid and a solid abrasive substance. The liquid may comprise water, an acid, another volatile or non-volatile liquid or a mixture of at least two of these. The solid substance may comprise quartz sand, an aluminium oxide such as corundum, other or a mixture thereof. If solid and liquid are provided separately, the pump 152 is arranged for mixing these.

The first end section 110 comprises first gripper fingers 114 that are swivellably mounted to a first end body 112 over first swivelling axes 116. The second end section 120 comprises second gripper fingers 124 that are swivellably mounted to a second end body 122 over second swivelling axes 126. The first end body 112, the second end body 122 and the middle body 132 preferably have a substantially cylindrical outer perimeter that is rotation symmetrical over a centre axis 102. The first swivelling axes 116 and the second swivelling axes 126 are preferably provided perpendicular to the centre axis 102. And in a preferred embodiment, they are parallel to tangents of the cylindrical section bodies.

Figure 1 B shows the device 100 with the first gripper fingers 114 swivelled over the first swivelling axes 116. Also the second gripper fingers 124 are swivelled over the second swivelling axes 126. The swivelling may be operated by means of finger drivers. The finger drivers may be provided on a per-section or a per-finger basis. The finger drivers may comprise mechanical, electro-mechanical or hydraulic actuators, other actuators or a combination thereof.

Furthermore, Figure 1 B shows the device 100 comprising a hydraulic cylinder 162 provided in the middle body 132. The hydraulic cylinder 162 is provided with a piston 164 arranged to move linearly in the hydraulic cylinder 162 under control of hydraulic liquid provided by a hydraulic control module 166 provided in the middle body 132. Movement of the piston 164 in the cylinder is controlled by means of the hydraulic control module 166. The piston 164 is mounted to the first end section 110. By operating the hydraulic cylinder 162 to move the piston 164 out of the cylinder 162, the first end section 110 is moved apart and away from the middle section 130 and the device 100 is elongated. Other types of linear actuators may be envisaged as well, in addition or as an alternative to the hydraulic cylinder, like a rack driven by a rotatable driver like an electromotor or a hydraulic motor. Optionally, a further hydraulic cylinder may be provided by moving the second end section 120 relative to the middle section 130.

Figure 2 shows another embodiment of how the diameter of the first end section 110 and the second end section 120 may be enlarged.

Figure 2 A shows a device 100. The device 100 comprises at the first end section 110 and at the second end section 120 frusto-conical rings 172. The frusto-conical rings 172 may be provided in segments or in one piece. Figure 2 B shows the frusto-conical rings 172 having a larger diameter than shown in Figure 2 A. The diameter of the frusto-conical rings 172 rings may be enlarged by applying a pressure to the inner side of the frusto-conical rings 172.

If the frusto-conical rings 172 are provided in one piece, it is noted the frusto-conical rings 172 preferably comprise an elastic material. If the frusto-conical rings 172 comprise multiple segments distributed of the circumferences of the frusto-conical rings 172, it is not of particular relevance whether they comprise an elastic material. In another embodiment based on the embodiment shown by Figure 2 A and figure 2 B, the first end section 110 and the second end section 120 comprise rings of which the diameter is substantially equal along the height of the rings.

Figure 2 C and Figure 2 D show in further detail how the diameter of rings 182 comprised by the first end section 110 and the second end section 120 may be enlarged. Figure 2 C and Figure 2 D show regularly shaped rings 182, rather than rings having a frusto-conical shape. It is noted that the embodiment disclosed by Figure 2 C and Figure 2 D may also be used with rings having a frusto-conical shape.

Figure 2 C shows a stationary part 184 comprised by either the first end section 110 or the second end section 120. Figure 2 C further shows a ring 182 of which the diameter may be enlarged. The ring 182 may be provided in one piece or in segments. The ring 182 comprises a sloped inner wall.

Within the ring 182, a wedge 190 is provided. The wedge 190 preferably has a frusto-conical shape. The wedge 190 is in this embodiment connected to a piston 192 of a hydraulic actuator for actuating the wedge 190 in a reciprocating linear movement. The wedge 190 may also be actuated by additional or alternative linear actuators, like a toothed rack driven by a rotatable toothed wheel.

Between the wedge 190 and the ring 182, bearings 186 are provided. The bearings 186 are in this embodiment arranged to roll or rotate over an axis perpendicular to the plane of the drawing. Other types of bearings may be envisaged as well.

Figure 2 D shows the same detail of the device 100 as shown by Figure 2 C, with the wedge 190 moved upward, as seen in the drawing. By moving the wedge 190 upward, force is applied to the inside of the ring 182 and the diameter of the ring 182 is enlarged. More in particular and in particular if the ring 182 is segmented, upward movement of the wedge 190 results in movement of the segments outwardly, substantially linear in a direction substantially perpendicular to the central axis 102 of the device.

In yet another embodiment, a linear actuator acts directly on the ring 182 or segments thereof, directly in a direction perpendicular to the central axis 102.

Figure 3 A shows a bumper pile 320 partially embedded in a seabed 310 and partially extending above a sea-level 330. Alternatively, the bumper pile 320 does not extend beyond the seal-level 330. The bumper pile 320 is in this embodiment a cylinder as part of a foundation of a former drilling platform of another off-shore structure. The bumper pile 320 is hollow, forming a conduit. The bumper pile 320 preferably has a substantially cylindrical shape. Within the bumper pile 320, the device 100 is provided for cutting the bumper pile 320. The process of cutting and lifting of the bumper pile 320 will be discussed in conjunction with Figure 4.

Figure 4 shows a flowchart 400. The flowchart comprises multiple objects that are briefly summarised as follows: 402 start 404 open bumper 406 descend device 408 fixate device 410 supply abrasive slurry 412 operate cutter 414 apply force to cylinder 416 sense force applied 418 move piston 420 sense movement of piston 422 suspend bumper 424 release lower gripper 426 move piston back 428 lift upper bumper section 430 remove device 432 end

The process starts in a terminator 402, followed by opening up the bumper pile 320 in step 404. In step 406, the device 100 is lowered in the bumper pile 320. This is shows by Figure 3 A. In step 408, the device 100 is fixated to the bumper pile 320 at a location where the bumper pile 320 is to be cut. This is depicted by Figure 3 B.

Figure 3 B shows the device 100 with the first end section 110 and the second end section 120 having an increased diameter. The diameter of first end section 110 and the second end section 120 is preferably increased such that the first end section 110 and the second end section 120 exert a significant force towards the inner wall of the bumper pile 320. This may be executed as discussed above.

In step 410, an abrasive slurry is provided to the device 100 for cutting the bumper pile 320. The abrasive slurry may be provided by a slurry supply module 340 through a slurry supply line 342. To this end, the slurry supply module 340 may be provided on a vessel at sea-level 330. In another embodiment, the slurry supply module 340 is comprised by the device 100, making the slurry supply line 342 obsolete. The slurry supply module 340 comprises a liquid reservoir 346, a solid abrasive reservoir 348 and a slurry compressor 344. A liquid from the liquid reservoir 346 and a solid abrasive from the solid abrasive reservoir 348 are mixed and provided under pressure to the device by means of the slurry compressor 344. Alternatively, the slurry is pre-mixed and held by the reservoir 346.

Within the device 100, the slurry is provided to the nozzle 136 (Figure 1 A) for cutting the bumper pile 320. This action is executed in step 412, in which the cutter is operated. After the cutting action, the bumper pile is separated in at least two sections, separated by a cut 322. As discussed, in one embodiment, the cutter comprised by the middle section 130 rotates over the centre axis 102 (Figure 1 A) of the device 100. The rotation action is powered by an electromotor, a hydraulic motor, another actuator providing a rotatory action or a combination thereof. In this embodiment, a hydraulic motor is used. To this end, a hydraulic supply module 350 is connected to the device 100 through a hydraulic supply line 352. The hydraulic supply module 350 comprises a hydraulic fluid reservoir 256 for a hydraulic fluid in general and oil in particular and a hydraulic compressor 354 for providing the hydraulic fluid under pressure.

The hydraulic supply line 352 comprises at least two conduits, a supply and a drain. Depending on whether further hydraulic controls for controlling operation of hydraulic elements of the device 100 are comprised by the device 100 or by a vessel carrying the hydraulic supply module 150, multiple hydraulic conduits may be provided. In case hydraulic controls are comprised by the device 100, electronic, mechanical and/or other control lines towards the device 100 may be provided. In another embodiment, the hydraulic supply module 350 is comprised by the device 100.

After the cutting action has been ended, the device 100 is used for checking whether the cutting has been successful. To this end, the hydraulic cylinder 162 (Figure 1 B) is operated. The hydraulic cylinder 162 is firstly operated for applying pressure - a force - on the first end section 110 relative to the middle section 130 in step 414. The pressure applied is in this embodiment sensed by a hydraulic pressure sensor 358 comprised by the hydraulic compressor 354 for sensing the pressure under which the hydraulic fluid is provided to the hydraulic cylinder 162 (Figure 1 B). This action is executed in step 416. In another embodiment, other pressure sensors may be provided at other locations for sensing the force applied by the device on the first pile part 324 relative to the second pile part, like strain gauges.

Figure 3 C shows the bumper pile 320 separated in an upper pile part 324 and a lower pile part 326. If the cutting action executed in step 412 has been successful, operation of the hydraulic cylinder 162 (Figure 1 B) will result in movement of the upper pile part 324 relative to the lower pile part 326 in step 418. The movement is sensed in step 420, for example by sensing a flow of hydraulic fluid in the hydraulic cylinder 162. Alternatively, other sensors may be employed, such as push buttons and other, for detection of movement of the piston 164 (Figure 1 B) relative to the hydraulic cylinder 162.

The force applied by the first end section 110 and the second end section 120 to the inner wall of the bumper pile 320 should be large enough for preventing substantial movement of the first end section 110 relative to the upper pile part 324 and for preventing substantial movement of the second end section 120 relative to the lower pile part 326 while operating the hydraulic cylinder 162.

It may be, however, that the cutting operation has not been successful. This is detected by sensing the force required to be executed by the hydraulic cylinder 162 until movement of the piston 164 (Figure 1 B) of the hydraulic cylinder 162 is detected - if any movement is detected until maximum force is applied. If the piston 164 does not move with force applied to the supply of hydraulic fluid to the hydraulic cylinder 162 exceeding a particular threshold, it may be determined that the upper pile part 324 has not yet been separated from the lower pile part 326. If this is the case, the cutting operation may be repeated. Alternatively, an increased force is applied to the hydraulic cylinder 162 and with that, to the piston 164 and from the middle section 130 to the first end section 110. This force may be applied for breaking any bonds that may still exist between the upper pile part 324 and the lower pile part 326.

If movement of the piston 164 relative to the hydraulic cylinder 162 is sensed, it is determined that the upper pile part 324 moves relative to the lower pile part 326. If this is the case, it is determined that the upper pile part 324 is properly separated from the lower pile part 326 and the movement force required for executing the movement of the upper pile part 324 relative to the lower pile part 326 is determined.

This movement force, required for moving the upper pile part 324, comprises three important components. A first component is determined by a weight of the upper pile part 324 and a second component is determined by an upward force of the seawater in accordance with Archimedes' principle. A third component is determined by a force exerted by sand and/or other materials in the seabed on the lower side of the upper pile part 324 hurried in the seabed.

The movement force may be used for determining what force may be required for suspending and lifting the upper pile part.

Subsequently, the upper pile part 324 is suspended by means of, for example, a crane provided on a vessel at the sea-level 330 in step 422. Next, the diameter of the second section 120 is reduced in step 424. This results in removing a gripping force between the device 100 and the inner wall of the lower pile section 326 in general and between the second end section 120 and the inner wall of the lower pile section 326 in particular. Next and optionally, the piston 164 is retracted in the hydraulic cylinder 162 in step 426.

With the second end section 120 of the device 100 released from the lower bumper section 326, the upper bumper section 324 is lifted in step 428. As the first end section 110 of the device 100 is not released from the upper bumper section 324, the device 100 is lifted together with the upper bumper section 214. This is depicted by Figure 3 D. Figure 3 D furthermore shows that the lower pile part 426 is provided with a filling 312. The filling preferably comprises material rom the seabed 310.

In particular providing the cut 322 in the bumper pile 320 at a level below the top of the seabed 310 allows automatic filling of the lower pile part 326. The cut 322 may also be provided above the top side of the seabed 310.

Finally, the device 100 is removed from the upper pile part 324 in step 430 and the process ends in terminator 432. The device 100 may subsequently be readied for a next use.

Thus far, the cutting of the bumper pile 320 has been disclosed as being executed by applying a fluid or a mixture of a solid and fluid under high pressure to the inner wall of the bumper pile 320, by means of the nozzle 136 (Figure 1 A), alternatively or additionally, separation of the lower pile part 326 from the upper pile art 324 may be executed by means of a rotating grinding wheel, a cutting torch, a shaped charge, other or a combination thereof. A shaped charge is an explosive charge shaped to focus the effect of the explosive's energy. Use of a shaped charge with the device 100 allows a cut in one explosion, which usually takes very little time. By virtue of using a shaped charge, rather than an explosive charge having a random shape, the shock caused by an explosion may be focussed outward, towards the wall of the bumper pile 320.

Thus far, a device has been discussed for cutting the bumper pile 320 from within. Whereas this is preferred, a similar tool having equivalent functionality for cutting the bumper pile 320 from the outside may also be executed from the outside. Furthermore, a device from cutting the bumper pile 320 from within may also be used for cutting conduits that have a substantially horizontal orientation, like pipes for transporting oil, gas, water, waste and/or other fluids.

In summary, the various aspects relate to moving a first conduit section of a conduit relative to a second conduit section of the conduit. The device comprises end sections comprising fixation modules. The fixation modules are arranged for fixating the ends sections to the applicable conduit sections. The device also comprises a middle section provided between the first and the second end section. The middle section comprises a linear actuator module for moving the middle section relative to at least one of the first end section and the second end section. This device is suitable for validating of cutting of the bumper piles or other conduits. Cutting tools currently used for cutting such conduits are not perfect and may leave material connecting the first conduit section and the second conduit section. By moving the first section away from the second section, one is sure both sections are well separated.

Expressions such as "comprise", "include", "incorporate", "contain", "is" and "have" are to be construed in a non-exclusive manner when interpreting the description and its associated claims, namely construed to allow for other items or components which are not explicitly defined also to be present. Reference to the singular is also to be construed in be a reference to the plural and vice versa.

In the description above, it will be understood that when an element such as layer, region or substrate is referred to as being “on” or “onto” another element, the element is either directly on the other element, or intervening elements may also be present.

Furthermore, the invention may also be embodied with less components than provided in the embodiments described here, wherein one component carries out multiple functions. Just as well may the invention be embodied using more elements than depicted in the Figures, wherein functions carried out by one component in the embodiment provided are distributed over multiple components. A person skilled in the art will readily appreciate that various parameters disclosed in the description may be modified and that various embodiments disclosed and/or claimed may be combined without departing from the scope of the invention.

Claims

An apparatus for moving a first conduit section of a conduit relative to a second conduit section of the conduit, the apparatus comprising: A first end section comprising a first fixation module for fixing the apparatus with respect to an inner wall of the first conduit section for limiting or preventing movement of the first end section relative to the first conduit section; A second end section comprising a second fixation module for fixing the device relative to an inner wall of the second conduit section for restricting or preventing movement of the second end section relative to the second conduit section; A center section provided between the first end section and the second end section, the middle section comprising a linear actuator module for moving the center section relative to at least one of the first end section and the second end section.

Device according to claim 1, wherein the linear actuator module comprises a force sensor connection for connecting a force measurement sensor in communication with the linear actuator module for measuring a force required for moving the first line section relative to the second line section.

Device according to claim 1 or 2, wherein the linear actuator module comprises a motion sensor connection for connecting a motion sensor in communication with the linear actuator module for measuring a movement of the first line section relative to the second line section.

Device as claimed in any of the foregoing claims, further comprising a separation module for dividing the pipe into the first pipe section and the second pipe section.

The device of claim 4, wherein the separation module comprises an abrasive cutting tool, comprising a nozzle for supplying a jet of high-pressure fluid for cutting the conduit.

The device of claim 4 or 5, wherein the separation module is comprised by the center section and is rotatably connected to the first end section and the second end section such that the separation module is rotatable about a central axis provided by the first end section, the center section and the second end section.

Device as claimed in any of the foregoing claims, wherein the linear actuator module comprises at least one of a hydraulic actuator, a mechanical actuator and an electromechanical actuator.

The device of claim 2, wherein the actuator module comprises a hydraulic cylinder and the force sensor connection is a hydraulic feed line for the hydraulic cylinder.

Device as claimed in any of the foregoing claims, wherein the first fixation module and the second fixation module are adapted to increase the cross-section of the first end section and the second end section, respectively.

Device as claimed in claim 9, wherein: The first fixation module comprises at least a first gripper which is pivotally connected via a first proximal end of the first gripper to the first end section over a pivot axis provided substantially perpendicular to a longitudinal axis of the device such that the proximal end of the gripper is closer to the center section than an opposite distal end of the first gripper; The second fixation module comprises at least a second gripper which is pivotally connected via a second proximal end of the second gripper to the second end section over a pivot axis provided substantially perpendicular to a longitudinal axis of the device such that the proximal end of the gripper is closer to the middle section is then an opposite distal end of the second gripper.

The apparatus of claim 9, wherein: the first fixation module comprises at least a first truncated conical section, a first top of which faces the center section and a second expansion module for expanding a first diameter of at least a first bottom of the first conical section ; and the first fixation module comprises at least a first truncated conical section, a first top of which faces the center section and a second expansion module for expanding a first diameter of at least a first bottom of the first conical section.

A method of moving a first conduit section of a conduit relative to a second conduit section of the conduit by means of a device, the method comprising: Fixing a first end section of the device relative to a first inner wall of the first conduit section for limiting or preventing movement of the first end section relative to the first conduit section; Fixing a second end section of the device relative to a second inner wall of the second conduit section for restricting or preventing movement of the second end section relative to the second conduit section; Operating a linear actuator provided between the first end section and the second end section for moving the first end section and the second end section relative to each other.

A method of dividing a conduit into a first conduit section and a second conduit section, the method comprising: Dividing the conduit into a first conduit section and a second conduit section by cutting the conduit; and The method of claim 12.

A method for determining a force required for hoisting a first conduit section comprising a conduit, the conduit further comprising a second conduit section, said second conduit section being positioned substantially stationarily in a medium, the method comprising: The method of claim 13; and determining a force needed to move apart from the first end section and the second end section.