NO334287B1 - Well plugging and pulling tools - Google Patents

Abstract

The invention relates to a set and retrieve device (1) for setting and / or retrieving a plug device in a well. A set-up and retrieval device comprises a first coupling device (2) adapted to be connected to a first coupling interface of the plug device and a second coupling device (3) adapted to be connected to a second coupling interface of the plug device. The device (1) further comprises a charging device (4) comprising a first fluid chamber (41), a second fluid chamber (42) and a displaceable charging piston (44) comprising a first end (44a) facing the second fluid chamber (42) and a second end (44b) facing an energy storage device (45), wherein the energy storage device (45) is charged with potential energy as the charge piston (44) is moved in a first direction (A) by pumping fluid from the first fluid chamber (41) to the second fluid chamber (42) and wherein the energy stored in the energy storage device (45) is discharged by providing a relative movement in a second axial direction (B) between the first coupling device (2) and the second coupling device (3). The device (1) further comprises a power supply device comprising a fluid pumping device (51) for pumping fluid between first and second fluid chambers (41, 42) via a first fluid channel (11) and a second fluid channel (12) as well as a volume adjustment device (7) comprising a first volume adjustment piston (71) slidably into the first fluid chamber (41).

Description

FIELD OF THE INVENTION

The present invention relates to a setting and retrieving device for setting and/or retrieving a plug device in a well.

BACKGROUND OF THE INVENTION

Several setting tools are known for setting a plug device into a well, for example an oil and/or gas well. Usually, such plug devices are bridge plugs (English: bridge plugs), straddle plugs (English: straddle packers), measuring device hangers (gauge hangers) etc., which are set, or fixed to the inside of the well during a period when a well operation is carried out. During this period, the setting tool must be removed from the well. Many such plug devices are retrievable, i.e. they must be retrieved from the well after the well operation. A recovery tool is used for such types of recovery operations.

Plug devices have a drive state or retracted state, where the outer diameter is smaller than the inner diameter of the well to transport the plug device in and out of the well. First, the setting tool is connected to the plug device and the plug device is guided in its running state to the desired location. Here, the setting tool brings the plug assembly to its set state before the setting tool is disconnected from the plug assembly and removed from the well. When the plug assembly is to be retrieved, the retrieval tool is introduced into the well, connected to the plug assembly, and the retrieval tool brings the plug assembly into the running condition and then the retrieval tool is transported together with the plug assembly out of the well. An example of a plug device is known from US 7,178,602 (in the name Bronnteknologiutvikling AS).

To bring the plug device from the run state to its set state, and then from its set state and back to its run state, the plug device comprises an activation interface. Often this actuation interface is activated by moving a first or radially inner part in an axial direction relative to a second or radially outer part. Shear pins are often used in the plug assembly to ensure that the plug assembly is in proper condition - ie, a predetermined force must break one or more sets of shear pins to activate the plug assembly. This is a common way to avoid that the plug device is accidentally brought to its set state during transport to and from the desired setting location in the well. Such cutting sticks can require a weight of up to about 2.5 tonnes to break.

US 5240077 describes a setting tool for setting a plug in a well. The tool is activated by a voltage signal to a DC motor that drives a hydraulic pump. The pump pumps fluid into a chamber, after which a piston in the chamber is pushed down to activate the setting of the plug.

The purpose of the invention is to provide a setting and retrieving device which provides an accurate and reliable activation of the plug device between its run position and set position.

Furthermore, it is a safety requirement of some oil and/or gas companies that pressurized devices are not permitted on the decks of platforms and ships due to the risk of personal injury. Therefore, one object of this invention is to provide a setting and retrieval device which has no internal pressure before the setting operation begins and which has no internal pressure after the retrieval operation is completed.

SUMMARY OF THE INVENTION

The present invention relates to a setting and retrieving device for setting and/or retrieving a plug device in a well, comprising: - a first coupling device adapted to be connected to a first coupling interface of the plug device, where the first coupling device comprises a substantially sleeve-shaped body; - a second coupling device adapted to be connected to a second coupling interface of the plug device, where the second coupling device comprises a substantially cylindrical body and where the first coupling device is provided radially outside the second coupling device;

characterized in that the device further comprises:

- a charging device comprising a first fluid chamber, a second fluid chamber and a displaceable charging piston comprising a first end facing the second fluid chamber and a second end facing a spring device, the spring device being charged with potential energy as the charging piston is moved in a first direction by pumping fluid from the first fluid chamber to the second fluid chamber and where the energy stored in the spring device is discharged by providing a relative movement in a second, axial, direction between the first coupling device and the second coupling device, where the first and second fluid chambers are provided radially between the first and other connecting devices; - a power supply device comprising a fluid pump device for pumping fluid between first and second fluid chambers via a first fluid channel and a second fluid channel; - a volume adjustment device comprising a first volume adjustment piston displaceable into the first fluid chamber.

In one aspect, the charging piston is movable in a second direction during discharge of the spring assembly.

In one aspect, the spring assembly is configured to be compressed by the charging piston.

In one aspect, the first fluid channel is provided between the fluid pumping device and the first fluid chamber and the second fluid channel is provided between the fluid pumping device and the second fluid chamber.

In one aspect, the first and second fluid chambers are separated by a first partition wall projecting radially inwardly from the substantially cylindrical body.

In one aspect, the first volume adjustment piston is axially displaceable, wherein axial displacement of the volume adjustment piston in a first direction decreases the volume of the first chamber and axial displacement of the volume adjustment piston in a second direction increases the volume of the first chamber.

In one aspect, the volume adjustment piston is provided radially between the first and second coupling means.

In one aspect, the volume adjustment device comprises a second axially displaceable volume adjustment piston comprising a first end that seals the opening between the first and second coupling devices, wherein a spring means is provided axially between a second end of the second volume adjustment piston and the first volume adjustment piston.

In one aspect, the volume adjustment device comprises a

motion retaining means attached to the first volume adjustment piston for restraining the movement of the second volume adjustment piston relative to the first volume adjustment piston.

In one aspect, the device comprises a trigger device arranged for triggering the discharge of the potential energy stored in the spring device.

DETAILED DESCRIPTION

Embodiments of the invention will now be described with reference to the attached drawings, where: Fig. 1 illustrates a cross-sectional view of a first embodiment in a first state; Fig. 2 illustrates a cross-sectional view of a second embodiment in a first state; Fig. 3 illustrates a cross-sectional view of a second embodiment in a second state; Fig. 4 illustrates a cross-sectional view of a second embodiment in a third state; Fig. 5 illustrates a cross-sectional view of a second embodiment in a fourth state, and

Fig. 6 illustrates a cross-sectional view of a third embodiment.

In the following, the term "plug device" is used to describe all types of devices that have a running state, where the device can be transported through a well, and a set state, where the device can be expanded and attached to the inner surface of the well.

The term "well" is used to describe oil and/or gas wells, oil and/or gas pipes, water wells and/or water pipes, or other types of wells and pipes where a plug device can be placed.

Reference is now made to fig. 1, where a first embodiment of a setting and retrieving device 1 is illustrated. The setting and retrieving device can be used for setting and/or retrieving a plug device in a well. In fig. the plug device is only indicated by its connection interfaces shown on the right in fig. 1. It should be noted that for most plug devices, the present invention can be used for both setting operations and retrieval operations. However, the plug device may be designed so that different tools are required for their setting operation and their retrieval operation, and thus it may be that the present invention can only be used for one of these operations.

The device 1 comprises a first connection device 2 comprising a first connection interface 2a adapted to be connected to a first connection interface 2a of the plug device. Thus, the first connection device 2 itself comprises a second connection interface 2a for connection to the first connection interface 2b of the plug device.

The device 1 also comprises a second connection device 3 comprising a second connection interface 3a adapted to be connected to a second connection interface 3b of the plug device. Thus, the second connection device 3 itself comprises a second connection interface 3a for connection to the second connection interface 3b of the plug device.

It should be noted that the design of the first and second connection devices 2, 3 will of course depend on the design of the first and second connection interface of the plug device. Many different designs for the first and second coupling devices 2, 3 are possible with the present invention as long as the first and second coupling devices 2, 3 provide that a relative movement between the first coupling device 2 and the second coupling device 3 causes a relative movement between the first coupling interface and the second connection interface of the plug device.

In the present embodiment, the first coupling device 2 comprises a substantially sleeve-shaped body 21 and the second coupling device 3 comprises a substantially cylindrical body 31. The connection interfaces of the first and second coupling devices 2, 3 are located at the lower end of the device 1, i.e. the the right end of the body 21, 31 in fig. 1.

The first coupling device 2 is provided radially outside the second coupling device 3, i.e. the cylindrical body 31 lies radially inside the sleeve-shaped body 21.1 the starting position, which will be described below, the outer surface of the first coupling device provides the outer surface of the lower part of the device 1.

A longitudinal or axial direction of the device 1 is defined by the central axis II.

The device 1 further comprises a charging device 4 and a main body 5. The main body 5 comprises a power supply device adapted to supply energy to the charging device 4. It should be noted that the main body 5 is only partially shown in the drawings.

The charging device 4 comprises a first fluid chamber 41 and a second fluid chamber 42. The first and second fluid chambers 41, 42 are separated by a partition wall 43. In this embodiment, the wall 43 projects radially inwards from the substantially cylindrical body 31, and is attached to the body 31. Alternatively can the wall 43 be part of the body 31.

In the present invention, the first and second fluid chambers 41, 42 are provided radially between the first and second coupling devices 2, 3, i.e. radially on the inside of the first coupling device 2 and radially outside the second coupling device 3.

The charging device 4 further comprises a displaceable charging piston 44 comprising a first end 44a facing the second fluid chamber 42 and a second end 44b facing an energy storage device 45. The second end 44b comprises a radially protruding stop flange to prevent the energy storage device 45 from being damaged. Thus, the first end 44a of the charging piston 44 protrudes into the second fluid chamber 42, and by movement of the charging piston 44, the volume of the second fluid chamber 42 can be increased or decreased.

The energy storage device 45 may be a spring device configured to be compressed by the charging piston 44. The spring device may be a gas spring, a disc spring or coil spring, etc. In fig. 1, the energy storage device 45 is a disc spring, which is supported by an area 5a of the main body 5. The energy storage device 45 is placed in a radial direction between the second coupling device 3 and an axially protruding element 53 of the main body 5.

The energy storage device 45 is charged with potential energy as the charge piston 44 moves in a first direction by pumping fluid from the first chamber 41 to the second fluid chamber 42. The energy stored in the energy storage device 45 is discharged by providing a relative movement between the first coupling device 2 and the second coupling device 3 in a second, axial, direction. The axial direction is parallel to the longitudinal direction or central axis II of the device 1.

In fig. 1, the first direction is indicated by arrow A and the second direction is indicated by arrow B. In fig. 1, the arrow A is opposite to the arrow B, i.e. charging movement of the charging piston 44 is parallel to the other, axial direction. However, it may also be possible for the movement of the charging piston 44 in the first direction A to be non-parallel to the second, axial direction B, since it is the fluid flow between the first and second chambers that provides the relative movement between the first coupling device 2 and the second the coupling device 3.

In the present embodiment, the charging piston 44 is also moved in the other direction B during discharge of the energy storage device 45.

It should also be noted that the discharge of the energy storage device 45 may provide that the first coupling device 2 is moved axially while the second coupling device 3 is stationary, or that the first coupling device 2 is held stationary while the second coupling device 3 is moved axially, or that both move in relative to each other in an axial direction. In this embodiment, the first coupling device 2 is moved axially while the second coupling device 3 is stationary during the discharge of the energy storage device. The second coupling device 3 is attached to the structure of the main body 5.

The main body 5 comprises a fluid pump device 51 for pumping fluid between first and second fluid chambers 41, 42 via a first fluid channel 11 and a second fluid channel 12.1 fig. 1 it is shown that the first fluid channel 11 is provided inside the cylindrical body 31 from the fluid pump device 51 to the first fluid chamber 41, while the second fluid channel 12 is provided inside the cylindrical body 31 from the fluid pump device 52 to the second fluid chamber 42.

The main body 5 further comprises batteries or another type of power source to supply energy to the fluid pump device 52.

The device 1 further comprises a volume adjustment device 7 to adjust the volume of the first fluid chamber 41. The volume adjustment device 7 comprises a first volume adjustment piston 71 which is displaceable into the first fluid chamber 41. The piston 71 is provided radially between the first and second coupling devices 2,3.

As described above, the first fluid chamber 41 is limited by the volume adjustment piston 71, the wall 43, the outer surface of the body 31 and the inner surface of the body 21. By pumping fluid into or out of the first fluid chamber 41, would the piston 71 be moved axially to the right or left respectively in fig. 1, if it is assumed that the first and second coupling devices 2, 3 are kept stationary in relation to each other. Therefore, axial displacement of the volume adjustment piston 71 in the first direction decreases the volume of the first chamber 41 and axial displacement of the volume adjustment piston 71 in the second direction increases the volume of the first chamber 41.

As described above, the second fluid chamber 42 is limited by the axially projecting member 53 of the main body 5, the piston 44, the wall 43, the outer surface of the body 31 and the inner surface of the body 21. By pumping fluid into in or out of the second fluid chamber 41, the piston 44 will be moved axially to the left or right respectively in fig. 1, when it is assumed that the first and second coupling devices 2, 3 are kept stationary in relation to each other.

The device 1 can also comprise a trigger device 6 adapted to trigger the discharge of the potential energy stored in the energy storage device 45. The trigger device 6 can, for example, be a shear pin that is cut off by a predetermined load. In the present embodiment, the release device 6 attaches the first coupling device 2 to an axially protruding element 53 of the main body 5 and thus axial displacement of the first coupling device 2 in relation to the second coupling device 3 is prevented. Alternatively, the release device 6 in the form of a shear pin can be placed on the plug device rather than on the set and retrieve device.

The operation of the device in fig. 1 will now be described.

Initially, the first fluid chamber 41 is filled with hydraulic fluid and the second fluid chamber 42 is empty or almost empty. The hydraulic oil in the first fluid chamber 41 can be equal to the pressure at the surface (platform/ship etc). A plug device to be placed in the well is connected to the first and second coupling devices 2, 3, which are known to a person skilled in the field. The plug device and the setting and retrieval tool are then lowered to the desired position in the well and the setting operation can begin. During the lowering process down the well, the volume adjustment piston 71 can move axially due to pressure fluctuations.

First, hydraulic fluid is pumped from the first chamber 41 to the second chamber 42 by means of the fluid pump device 51 via the first fluid channel 11 and the second fluid channel 12. The fluid pump device 51 is supplied with power from the power supply device.

Thus, as fluid is pumped out from the first chamber 41 , the volume of the first chamber 41 decreases as the volume adjusting piston 71 moves toward the wall 43 .

As fluid is pumped into the second chamber 42, the volume of the second chamber 42 increases as the charging piston 44 moves towards the energy storage device 45 and stores the potential energy in the energy storage device 45.1 this embodiment, the potential energy is stored by compressing a disc spring.

When the potential energy 42 has reached a certain level, the trigger device 6 is triggered, either at the plug device or at the setting and retrieving device 1, and an axial movement of the first coupling device 2 in relation to the second coupling device 3 will no longer be prevented. Thus, the first coupling device 2 is pressed to the right in fig. 1 due to the energy stored in the energy storage device 45.

The result is that a controlled axial movement of the first coupling device 2 is achieved in the form of a stroke. The axial movement is transferred to the plug device and leads to a setting action of the plug device, for example by radial expansion of a packer, an anchor etc.

The process can then be repeated by pumping more fluid from the first chamber 41 to the second chamber 42 to charge the energy storage device 45 again. A second trigger device may then be provided for triggering the second axial displacement of the first coupling device 2. The second trigger device may be configured to withstand a higher load before breaking than that of the first trigger device. The process can be repeated as many times as necessary, provided that the volume of the first fluid chamber 41 is sufficiently large. If the first axial movement does not move the first coupling device far enough, the fluid pump is used to axially move the first coupling device until the second release device prevents further axial movement. When the plug device is set, the first and second coupling devices 2, 3 are disconnected from the plug device and the device 1 is brought back to the surface. The pressure in the first and second fluid chambers 41, 42 can be equalized when there is no well pressure on the right side of the volume adjustment piston 71 in fig. 1 to avoid pressure inside the device 1 when it is recovered to the deck on the platform.

Other embodiment

The second embodiment will now be described with reference to Figs 2-5.

The second embodiment has the same characteristics and functions as the device in the first embodiment, and the same reference numbers are used for the same functions. These functions will therefore not be described here in detail.

The volume adjustment device 7 in the second embodiment comprises a second axially displaceable precharge piston 72 comprising a first end 72a which seals the opening between the first and second coupling devices 2, 3, where a spring device 73 is provided axially between a second end 72b of the second precharge piston 72 and the first volume adjustment piston 71.1 the present embodiment, the spring device 72 is a disc spring. The pre-charge stamp 72 is used for pre-charging the charging device 4.

The volume adjustment device 7 may also comprise a movement holding device 74 attached to the first volume adjustment piston 71 to limit the movement of the second precharge piston 72 in relation to the first volume adjustment piston 71.

The operation of the device in fig. 2-5 will now be described.

As described, the first and second fluid chambers 41, 42 are initially filled with hydraulic fluid. The volume of the second chamber is small, almost all the hydraulic fluid of the plug device is provided in the first fluid chamber 41. The hydraulic oil in the first and second fluid chambers 41, 42 can be equal to the pressure at the surface (platform/ship etc). Furthermore, the location of the various parts of the volume adjustment device 7 as shown in fig. 2.

The plug device and the setting and retrieval tool are connected to each other and are lowered to the desired position in the well, after which the setting operation can begin. Since the well pressure is greater than the surface pressure, the well pressure will press the second precharge piston 72 against the first volume adjustment piston 71 during lowering into the well, and thus the spring device 73 will be compressed, as shown in fig. 3.

In fig. 4, it is shown that the pumping device has pumped fluid from the first chamber 41 to the second chamber 42: The volume adjusting piston 71 has moved towards the wall 43 and the charging piston 44 has moved towards the main body 5 and has started charging the energy storage device 45. It should be noted that the second piston 72 of the volume adjustment device 7 is limited due to the movement of the movement holding device 74 attached to the first volume adjustment piston 71. However, the volume adjustment piston 71 moves in the same direction as the charging piston 44. When the load threshold of the trigger device 6 is reached, the potential energy stored in the energy storage device is released through an axial displacement of the first coupling device 2. This operation can be repeated one or more times depending on the design of the device 1, as mentioned above for the first embodiment.

In fig. 5 it is shown that the first coupling device 2 has been shifted to the right in relation to the second coupling device 3, and has contributed to a corresponding relative axial displacement between the connection interface of the plug device. In fig. 5, the end position for the axial movement is achieved by the wall 43 abutting a radially projecting stop 32 of the body 31 of the second coupling device 2.

When the device 1 is to be recovered, the fluid pressure in the first and second chambers 41, 42 can be actively equalized by means of the pump device or by opening a third fluid channel between chambers 41, 42. The second piston 72 of the volume adjustment device 7 will also be moved and equalize the pressure inside in the device 1 with the surrounding pressure.

Therefore, it is achieved that when the device 1 is retrieved from the well and to the deck of the platform, there is no internal pressure in the device 1.

Third embodiment

A third embodiment is shown in fig. 6. The third embodiment has the same characteristics and functions as the device in the second embodiment, and the same reference numbers are used for the same functions. These functions will therefore not be described here in detail.

In the third embodiment, the substantially cylindrical body 31 of the coupling device 3 comprises a third fluid channel or bleeding channel 33 between an inner section 34 and an outer section 35. The inner part 34 is closer to the main body 5 than the outer part 35. The bleeding channel 33 provides that fluid can flow between the first and second chambers 41, 42 to equalize the pressure difference between the first and second liquid chambers. The bleeding channel 33 may comprise a separate channel provided in the body 31, as indicated by the dashed line in fig. 6, or it may comprise one or more longitudinal grooves in the body 31.

Alternatively, it may form a conical area of the body 31, the inner section 34 having a larger diameter than the outer section 35. The bleeding channel is closed in the initial state but will open when the wall 43 abuts the radially projecting stop 32 as shown in fig. 6, here it is shown that the wall 43 passes the left opening of the channel 33, and thus fluid is allowed to flow between the first and second chambers 41, 42.

Thus, the fluid pressure is adjusted between the first chamber 41 and the second chamber 42 in the state shown in fig. 6. This ensures that when the device 1 is retrieved from the well and to the deck on the platform, there is no internal pressure in the device 1.

It should be noted that the first, second and third embodiments described above can be used to set and retrieve other types of well plug devices or well tools in addition to those mentioned above. It should also be mentioned that the present invention can also be used to insert and retrieve plug devices and tools in other types of wells, such as water wells.

Furthermore, it should be noted that the present invention can be used for both setting operations and retrieval operations. However, there may be plug devices that may require a different tool for either the setting operation or the retrieval operation. In this situation, the device according to the invention will be only a setting tool or only a retrieval tool.

It should also be noted that in addition to the elements and parts of the device 1

described above, the device also includes seals, O-rings etc to ensure that the first and second chambers 41, 42 are tight with regard to fluid. Furthermore, the body 31 and the body 21 can comprise several smaller parts to facilitate the assembly of the device 1.

Claims (10)

1. Setting and retrieving device (1) for setting and/or retrieving a plug device in a well, comprising: - a first connection device (2) adapted to be connected to a first connection interface of the plug device, where the first connection device (2) comprises a substantially sleeve-shaped body (21); - a second coupling device (3) adapted to be connected to a second coupling interface of the plug device, where the second coupling device (3) comprises a substantially cylindrical body (31) and where the first coupling device (2) is provided radially outside the second coupling device ( 3); characterized in that the device (1) further comprises: - a charging device (4) comprising a first fluid chamber (41), a second fluid chamber (42) and a displaceable charging piston (44) comprising a first end (44a) facing the second fluid chamber (42) ) and a second end (44b) facing a spring device (45), where the spring device (45) is charged with potential energy as the charging piston (44) is moved in a first direction (A) by pumping fluid from the first fluid chamber (41) to the second fluid chamber (42) and where the energy stored in the spring device (45) is discharged by providing a relative movement in a second, axial, direction (B) between the first coupling device (2) and the second coupling device (3), where the first and second fluid chambers (41, 42) are provided radially between the first and second coupling devices (2, 3); - a power supply device comprising a fluid pump device (51) for pumping fluid between first and second fluid chambers (41, 42) via a first fluid channel (11) and a second fluid channel (12); - a volume adjustment device (7) comprising a first volume adjustment piston (71) displaceable into the first fluid chamber (41). 2. Device according to claim 1, where the charging piston (44) is movable in the other direction (B) during discharge of the spring device (45). 3. Device according to claim 1 or 2, wherein the spring device (45) is configured to be compressed by the charging piston (44). 4. Device according to any of the above-mentioned claims, where the first fluid channel (11) is provided between the fluid pump device (51) and the first fluid chamber (41) and the second fluid channel (12) is provided between the fluid pump device (51) and the second the fluid chamber (42). 5. Device according to claim 1, where the first and second fluid chambers (41, 42) are separated by a first partition wall (43) which projects radially inwards from the substantially cylindrical body (31). 6. Device according to claim 1, wherein the first volume adjustment piston (71) is axially displaceable, wherein axial displacement of the volume adjustment piston (71) in a first direction reduces the volume of the first chamber (41) and axial displacement of the volume adjustment piston (71) in a second direction increases the volume of the first chamber (41). 7. Device according to claim 6, where the volume adjustment piston (71) is provided radially between the first and second coupling devices (2, 3). 8. Device according to claim 6, wherein the volume adjustment device (7) comprises a second axially displaceable volume adjustment piston (72) comprising a first end (72a) which seals the opening between the first and second coupling devices (2, 3), where a spring device (73 ) is provided axially between a second end (7b) of the second volume adjustment piston (72) and the first volume adjustment piston (71). 9. Device according to claim 8, where the volume adjustment device (7) comprises a movement holding device (74) attached to the first volume adjustment piston (71) to stop the movement of the second volume adjustment piston (72) in relation to the first volume adjustment piston (71). 10. Device according to claim 1, where the device (1) comprises a trigger device (6) arranged for triggering the discharge of the potential energy stored in the spring device (45).