AU2017100355A4 - Method of Live Well Completion - Google Patents

Abstract

A method of completing a live well utilising spoolable coil is provided, which enables live-well completion and work-overs. The method includes: introducing, into the well, a spoolable coil, the spoolable coil including a progressive cavity pump (PCP) stator at a lower end thereof; introducing, into the spoolable coil, a PCP rotor; and installing a PCP drive head coupled to rotor. n --

Description

1

METHOD OF LIVE WELL COMPLETION 2017100355 28 Mar 2017

TECHNICAL FIELD

[0001] The present invention relates to wells, such as coal seam gas wells, and in particular to the introduction of completions therein.

BACKGROUND ART

[0002] During the construction of wells (such as gas and petroleum wells, coal seam gas wells, water wells, geothermal wells etc.) a completion is introduced into the well. Completions typically include a number of components, including production tubing (through which material drawn from the well passes to the surface), a wellhead, and valves.

[0003] In some wells, artificial lift equipment is required in order to lift wellbore fluids to surface. In coal seam gas (CSG) wells, jointed tubing is used and a progressive cavity pump (PCP) is often used to extract water from the coal seam (know as dewatering) in order to effectively produce the gas. In particular, as the water is produced from the coal seams, the down-hole pressure reduces, which enables the flow of natural gas from the rock into the wellbore and to surface.

[0004] During the life of a CSG well, the PCP generally needs to be replaced a number of times. In particular, the PCP may become inoperable due to blockage with formation solids or fines, the performance of the PCP may be reduced due to stator elastomer swelling, and changes in water production from coal seams may require a change in size (capacity) of the PCP used.

[0005] In order to replace the PCP in a well, which is commonly known as a “work-over”, the jointed tubing must be pulled out of the wellbore. Due to the nature of the operation and the characteristics of the jointed tubing, a work-over is normally performed on a “dead” well. In order to “kill” a CSG well, water is pumped into the wellbore from the surface to form a column of fluid above the coal seam. This in turn creates hydrostatic pressure higher than the pressure from the coal seam, which keeps the well under pressure control (over-balanced).

[0006] There are a number of operational and safety concerns associated with killing CSG wells. In particular, it is very time consuming and costly to remove the water from a coal seam, and as such, pumping water back every time a work-over is required is not efficient. Furthermore, the permeability of coal seams increases over time, and as such, it becomes more difficult to “kill” the wells. As a result, more time and water is required to kill the well, and 2 2017100355 28 Mar 2017 there is a risk of the well becoming “live” during the work-over, resulting in a wellbore blow-out with potential catastrophic consequence to personnel and assets.

[0007] As water is re-injected into the coal seams to kill a well, gas production after the work-over is completed is delayed as the water must again be removed, and in many cases the rate of gas production after the well has been killed (and reinstated) is reduced. Furthermore, during the work-over operation, it is often required to clean the wellbore prior deploying a production string with a new PCP, and such clean-out operations are often inefficient or difficult because the well needs to be kept in an over-balanced state.

[0008] Several attempts have been made to overcome the challenges related to killing the wells in order to perform work-overs. In one example, snubbing equipment has been used to enable the jointed tubing to be installed or pulled out of the well without killing the well. However, such methods are very expensive and slow.

[0009] In other examples, surface pressure vacuum equipment has been used to enable live-well work-over operations. However, such methods requires significant additional equipment and are based on a pressure balance within the wellbore near surface, which could be easily compromised if wellbore fluid composition changes during the work-over operation, resulting in considerable safety risk.

[0010] As such, there is clearly a need for improved methods of live well completion.

[0011] It will be clearly understood that, if a prior art publication is referred to herein, this reference does not constitute an admission that the publication forms part of the common general knowledge in the art in Australia or in any other country.

SUMMARY OF INVENTION

[0012] The present invention is directed to methods of live well completion, and live wells completed using the method, which may at least partially overcome at least one of the abovementioned disadvantages or provide the consumer with a useful or commercial choice.

[0013] With the foregoing in view, the present invention in one form, resides broadly in a method of completing a live well, the method including: introducing, into the well, a spoolable coil, the spoolable coil including a progressive cavity pump (PCP) stator at a lower end thereof; introducing, into the spoolable coil, a PCP rotor; and 3 coupling a PCP drive to the PCP rotor. 2017100355 28 Mar 2017 [0014] By using a coiled tubing instead of jointed tubing, as was done in the prior art, live-well completion and work-overs are possible. In particular, work-overs may be performed without killing the well.

[0015] The method may comprise forming a seal against the spoolable coil. The seal may be formed once the PCP stator is at the required depth.

[0016] The method may include hanging the coil in a well-head of the well.

[0017] The method may include retrieving the PCP rotor, and withdrawing the spoolable coil from the well under pressure (i.e. without killing the well).

[0018] The step of withdrawing the spoolable coil from the well under pressure may include: installing an isolation device on a wellhead, and actuating the isolation member of the isolation device to form a seal between the isolation member and an inner surface of the spoolable coil.

[0019] It is envisaged that the method of the present invention may be used with any suitable well, such as an oil well or a gas well. More preferably, the well comprises a coal seam gas well that requires dewatering. Preferably, the method of the present invention may be used with wells that have already been drilled and have a wellhead installed. The wells may have already been in production, or may be in a pre-production condition.

[0020] It will be understood that the spoolable coil may be of a tubular construction, and may be of different sizes depending on well requirement. The spoolable coil may, for example, be 2 3/8 inch outer diameter (OD), 2 7/8 inch OD, 3 1/4 inch OD, or 3 1/2 inch OD. Similarly, the coil may be formed of different metal grades or wall thickness, or made of other materials such as fiber glass, according to need.

[0021] In a preferred embodiment, the well may be isolated prior to introducing the spoolable coil into the well. By “isolated”, it will be understood that this is intended to refer to a situation in which fluid is precluded from exiting the well through the wellhead. This may also be referred to as the well being “shut-in”.

[0022] Shutting in a well is a largely conventional process, and the well may be shut-in using any suitable technique. In a preferred method of the invention, the shutting in of the well occurs in a wellhead. The wellhead may comprise any suitable components, although in a 4 2017100355 28 Mar 2017 preferred method of the invention, the wellhead may include one or more isolation devices. Any suitable isolation devices may be provided.

[0023] The well may be shut-in by closing valves of a well head.

[0024] One or more control devices may be connected to the wellhead. Any suitable control devices may be used, although in a preferred embodiment of the invention, the one or more control devices may be adapted to preclude the uncontrolled flow of fluid from the well. In a preferred embodiment of the invention, the one or more control devices may comprise a blowout preventer (BOP).

[0025] In a preferred embodiment of the invention, a flow tee may be connected to the wellhead. The flow tee may be connected to the wellhead at any suitable location, although in a preferred embodiment of the invention the flow tee may be connected at a point above the BOP, such that the BOP is located between the flow tee and the well. In turn the flow tee may be connected to an injector adapted to introduce the spoolable coil to the well.

[0026] The spoolable coil may be introduced into the well through the wellhead. More specifically, the spoolable coil may be introduced into the well through the flow tee, a BOP (such as a coil tubing BOP) a tubing hanger assembly and/or tubing hanging equipment, such a rod lock.

[0027] The spoolable coil may be introduced into the well to any suitable depth.

[0028] It is envisaged that the introduction of the spoolable coil into the well may be achieved by providing a spool of coil on a reel unit and using an injector to introduce the coil into the well.

[0029] As mentioned, the spoolable coil may be of any suitable size. However, it will be understood that the exact diameter of the spoolable coil used will depend largely on the type, depth and diameter of the well in which the spoolable coil is to be used.

[0030] The materials from which the spoolable coil is manufactured are not critical to the invention, and it will be understood that different types of coiled tubing could be used depending on the type of well, the size of the well and so on.

[0031] Once the spoolable coil is in place within the well, a seal may be formed against the spoolable coil. Preferably, the seal may be formed against an outer surface of the spoolable coil. The seal may be formed at any suitable location within the well or wellhead. In a preferred 5 2017100355 28 Mar 2017 embodiment of the invention, however, the seal may be formed against the spoolable coil in a tubing hanger assembly.

[0032] In a preferred embodiment, a coiled tubing slip connector is used in an “up-side-down” configuration to hang the coil. The coiled tubing slip connector may be coupled to the coil by a Combination Anti-Rotation Self Aligning Connector (CARSAC) connector.

[0033] Alternatively, a rod lock may be used to hang the coil. Setting the tubing hanger may isolate the well by actuating one or more sealing mechanisms to form a seal against the spoolable coil in order to preclude a flow of fluid from exiting the well around the spoolable coil.

[0034] In a preferred embodiment of the invention, once the spoolable coil has been introduced to the well and a seal formed against the spoolable coil, a length of the spoolable coil may be exposed above the wellhead (and, specifically, above the BOP and flow tee, if present) to allow for the removal of a portion thereof. Alternatively, a “work window” typically used for coiled tubing operations may be used.

[0035] Removal of “excess” coil above the wellhead may be achieved using any suitable technique. Preferably, the coil is cut about its circumference and to such a depth that the coil is cut entirely through. The cutting of the coil may be achieved using any suitable technique, such as one or more shears, power tools, coil cutting tools or the like, or a combination thereof.

[0036] In an alternative embodiment of the invention, the spoolable coil may be cut prior to its introduction into the well.

[0037] In some embodiments of the invention, the coil may be lifted, raised or tensioned. The coil may be lifted, raised or tensioned using any suitable technique, any suitable lifting device may be used, such as a block and tackle, lever or crane.

[0038] Following the installation of the coil, the PCP rotor and rods may be installed into the coil using any suitable method, including using a flush-by unit, a crane with an appropriate work-floor and lifting and make up equipment.

[0039] Completion of the assembly of the wellhead may be achieved by adding any further suitable components thereto, and it will be understood that the additional components will vary depending on the nature of the well, etc.

[0040] Following the assembly of the wellhead, it is envisaged that the well will be returned to a “live” condition, meaning that fluid from the well may begin to flow into an inlet portion 6 and up the coil to the wellhead. 2017100355 28 Mar 2017 [0041] When a work-over operations is required (e.g. to change the PCP), a flush-by unit (or alternative method) may be used to remove the rods and rotor of the PCP. A flare line may be used to allow the well to flow gas in an annular formed between a production casing and a production string of the coil.

[0042] Once the rods and PCP rotor have been removed from the wellbore an isolation device may be deployed in the coil. The isolation device may be pushed inside the coil, and an isolation member thereof may be actuated to form a seal between the isolation member and an inner surface of the spoolable coil.

[0043] The isolation device may comprise: a working piston located at least partially within a casing and movable bi-directionally within the casing; a first force transfer member associated with a first side of the working piston and adapted to extend at least partially through a first end wall of the casing; and a second force transfer member associated with a second side of the working piston and adapted to extend at least partially through a second end wall of the casing.

[0044] Similarly, isolation members, such as darts, may be injected in the coil, under pressure, using an adequate device, in order to create an effective mechanical seal at surface.

Such isolation members may include an actuation member movable relative to a body thereof, between the rest condition and a use condition, which enables the injection and then activation of sealing elements.

[0045] In use, it is envisaged that the isolation member may be inserted into a spoolable coil inside the well or wellhead.

[0046] The isolation member may be of any suitable size, shape or configuration.

[0047] It is envisaged that, when the isolation device is in the rest condition, a sealing portion thereof may have a diameter that is no greater than the remainder of a body of the isolation device, and no greater than the inside diameter of the spoolable coil. This ensures that, when the isolation member is introduced into a spoolable coil, the sealing portion does not prevent the isolation member from moving freely within the spoolable coil.

[0048] The sealing portion may form a seal against the inner surface of the spoolable coil in any suitable manner. For instance, movement of the actuation portion into the use condition may force the sealing portion outwardly from the body into abutment with the inner surface of the 7 2017100355 28 Mar 2017 spoolable coil. More preferably, however, the sealing portion is fabricated from a deformable material, such that movement of the actuation member results in deformation of the sealing portion, the deformation urging the sealing portion into abutment with the inner surface of the spoolable coil.

[0049] In addition, it is envisaged that, in some embodiments of the invention, a number of additional steps may be required prior to installing the isolation device on the wellhead. For instance, it may be desirable to ensure that there is no pressure or flow through the wellhead. It is envisaged that this may be checked by opening one or more flow tees. In this embodiment of the invention, if this check reveals that no pressure or flow exists through the wellhead, one or more pieces of equipment (such as, but not limited to, a well cap, a flow tee, a wellhead penetrator or the like) may be removed from the wellhead.

[0050] The isolation device may be installed at any suitable location on the wellhead. Preferably however, the isolation device is installed on a flow tee. Similarly, the isolation member maybe deployed any suitable distance into the spoolable coil.

[0051] In a preferred embodiment of the invention, the isolation member may be deployed a relatively short distance into the spoolable coil, such that the isolation member remains within the wellhead. Preferably, the isolation member is deployed no further than 1 m into the spoolable coil. More preferably, the isolation member is deployed no further than 50 cm into the spoolable coil. Most preferably, the isolation member is deployed about 30 cm into the spoolable coil.

[0052] In a preferred embodiment of the invention, once the isolation member has been actuated to form a seal with the inner surface of the spoolable coil, a pressure test may be conducted to ensure that sufficient sealing between the isolation member and the inner surface of the coil exists. In a preferred embodiment of the invention the pressure test may be conducted at wellbore pressure. More preferably, the pressure test may be conducted at greater than wellbore pressure. In a specific embodiment of the invention, the pressure test may be conducted at a pressure of about 1000 psi (6.9 MPa) above wellbore pressure.

[0053] If the seal passes the pressure test, the isolation device may be withdrawn from the wellhead. This may be achieved using any suitable technique. For instance, rotation of rotation members of the isolation device may result in fasteners (e.g. shear pins) connecting the isolation device to the isolation member to fracture, thereby disconnecting the isolation member from the isolation device. At this point, the isolation device may be withdrawn from the wellhead.

[0054] Alternatively, an upward force may be applied to the isolation device to fracture the 8 2017100355 28 Mar 2017 fasteners connecting the isolation device to the isolation member, while retaining the seal between the isolation member and the inner surface of the spoolable coil.

[0055] Prior to connecting the one or more connection members to the spoolable coil, a number of other steps in the method may be conducted. For instance, following the withdrawal of the isolation device, other items of equipment may be removed from the upper end of the wellhead. Any suitable items of equipment may be removed, such as, but not limited to, a flow tee, rod lock or the like.

[0056] It is envisaged that, prior to connecting the one or more connection members to the spoolable coil, one or more items of equipment may be connected to the upper end of the wellhead. Any suitable items of equipment may be connected, such as, but not limited to one or more flow tees, a BOP or the like, or any suitable combination thereof. In some embodiments of the invention an injector adapted to facilitate introduction of a spoolable coil to the well may be connected to the wellhead. Alternatively, these items of equipment may be connected to the wellhead following the connection of the connection members to the spoolable coil.

[0057] Any suitable connection members may be connected to the spoolable coil in order to facilitate its withdrawal from the well. For instance, one or more grips, clamps, hooks, or the like may be inserted into the wellhead and engaged with an upper portion of the spoolable coil. An upward force may then be applied to the connection members in order to withdraw the spoolable coil from the well.

[0058] More preferably, the one or more connection members may be associated with coiled tubing located on a reel unit. In this embodiment of the invention, the one or more connection members may be adapted to connect two lengths of coiled tubing together. Thus, the connection members may be coil connection members. Any suitable coil connection members may be used, such as, but not limited to one or more roll on connectors, dimple connectors, or the like, or any suitable combination thereof.

[0059] In this embodiment, it is envisaged that coiled tubing located on a reel unit may be introduced to the wellhead through an injector. The coil connection members may be provided on the end of the coiled tubing, such that the coil connection members are received in the spoolable coil within the wellhead, thereby connecting the spoolable coil within the well to the coiled tubing on the reel unit.

[0060] Once the spoolable coil and the coiled tubing on the reel unit are connected, the reel unit may then be actuated to withdraw the spoolable coil from the well. Prior to this, it may be 9 2017100355 28 Mar 2017 desirable to conduct a pressure test on either side of any seals that may exist in the wellhead to ensure that the pressure on each side of the seal is substantially equal.

[0061] In addition, prior to withdrawing the spoolable coil from the well, any seals may exist in the wellhead (such as those between a rod lock and the spoolable coil) may be removed or disengaged.

[0062] Any of the features described herein can be combined in any combination with any one or more of the other features described herein within the scope of the invention.

[0063] The reference to any prior art in this specification is not, and should not be taken as an acknowledgement or any form of suggestion that the prior art forms part of the common general knowledge.

BRIEF DESCRIPTION OF DRAWINGS

[0064] Various embodiments of the invention will be described with reference to the following drawings, in which: [0065] Figure 1 illustrates a perspective view of a coal seam gas (CSG) well installation, according to an embodiment of the present invention; [0066] Figures 2-9 illustrates steps in a method of installing a spoolable coil in a well, according to an embodiment of the present invention; and [0067] Figures 10-13 illustrates steps in a method of removing a spoolable coil from the well, according to an embodiment of the present invention.

[0068] Preferred features, embodiments and variations of the invention may be discerned from the following Detailed Description which provides sufficient information for those skilled in the art to perform the invention. The Detailed Description is not to be regarded as limiting the scope of the preceding Summary of the Invention in any way.

DESCRIPTION OF EMBODIMENTS

[0069] Figure 1 illustrates a perspective view of a coal seam gas (CSG) well installation 100, according to an embodiment of the present invention. As described in further detail below, the CSG well installation 100 utilises coiled tubing as production tubing, and is configured to enable work-overs without killing the well. ίο 2017100355 28 Mar 2017 [0070] While the installation 100 is not limited to any particular well type, testing appears to indicate that the installation 100 is particularly suited to shallow (less than ~800m depth), vertical CSG wells, which are prevalent in Australia.

[0071] The well installation 100 comprises a vertical wellbore 105, and a wellhead 110 situated thereon. The vertical wellbore 105 and the wellhead 110 are largely conventional. The wellhead 110 includes valves 110a in a flow tee, which are closed, thereby shutting in the well (i.e. preventing the flow of fluid from the wellbore 105 through the wellhead 110).

[0072] A method of live-well completion is now described with reference to the CSG well installation 100.

[0073] Figure 1 illustrates the introduction of coiled tubing 115 into the well, according to one embodiment of the present invention. The coiled tubing 115 comprises a spoolable coil, and includes a PCP stator at a lower end of the coil. As such, when the coiled tubing 115 is installed, the PCP stator forms part of a PCP at a lower end of the coil.

[0074] The well installation includes a blow out preventer (BOP) 120 positioned on an upper end of the wellhead 110, and a coil tubing stripper and lubricator 125 is provided above BOP 120. A coil tubing injector head 130 is provided above the coil tubing stripper and lubricator 125, which is configured to feed the coiled tubing 115 through the coil tubing stripper and lubricator 125, the BOP 120, the wellhead 110, and ultimately into the wellbore 105.

[0075] A crane 135 used to support the coil tubing injector head 130 by one or more supports (not illustrated), and a coil tubing reel unit 140 provides the coiled tubing 115 into the well without joins, in contrast to the jointed tubing of the prior art.

[0076] The coil tubing reel unit 140 may be mounted on a prime mover, a trailer or the like, to enable efficient transportation thereof.

[0077] Once the coiled tubing 115 (and thus the PCP stator) is at the required depth, a seal is formed against the spoolable coil 115.

[0078] The skilled addressee will appreciate that the well may be isolated prior to introducing the spoolable coil 115 into the well in that fluid is precluded from exiting the well through the wellhead.

[0079] Figure 2 illustrates a perspective view of the CSG well installation 100, with the BOP 120 enlarged. 11 2017100355 28 Mar 2017 [0080] The BOP 120 comprises a channel 205 through which the coiled tubing 115 extends. The BOP 120 comprises pipe slips 210, which releasably seal against the coiled tubing 115 to provide a seal therewith.

[0081] In order to allow the coiled tubing 115 to pass through the BOP 120 during installation, the pipe slips 210 are moved into an open position. When the coiled tubing 115 is at the required depth, the pipe slips 210 are moved into a closed position, which provides a seal around the coiled tubing 115.

[0082] The coil 115 is then installed and hanged as outlined below.

[0083] The coil tubing injector head 130 and the coil tubing stripper and lubricator 125 are disconnected from and lifted away from the wellhead 110, as illustrated in Figure 3. This also lifts the coil 115 to create an exposed length thereof, which is cut using a coil cutting tool (not shown) and dressed. If necessary a relief cut may be placed in a different location in the exposed length of coil 115 (preferably above the point at which the coil 115 is cut through) prior to cutting the coil 115.

[0084] In an alternative embodiment of the invention, the spoolable coil may be cut prior to its introduction into the well.

[0085] As illustrated in Figure 4, a lower slip connector 405 is secured to the coil. The slip connector 405 is attached to the coiled by means of a slip mechanism which provides resistance to tensional and torsional loads.

[0086] As illustrated in Figure 5, a tubing mandrel 505 is then connected to the lower slip connector 405 by a first cross over connector 510. A Combination Anti-Rotation Self Aligning Connector (CARSAC) connector 515 is then coupled to an upper end of the tubing mandrel 505 by a second cross over connector 520.

[0087] The CARSAC connector 515 allows an upper slip connector 525, and an upper coiled tube 530 to be connected without the need to rotate the work coil 115, to hang the coil 115. As such, the upper slip connector 525 is used in an upside down configuration to hang the coil 115.

[0088] The coil assembly comprising the coil 115, the lower slip connector 405, the first cross over connector 510, the tubing mandrel 505, the second cross over connector 520, the CARSAC connector 515 and the upper slip connector 525, are lowered and the mandrel 505 is 12 landed into the wellhead 110. 2017100355 28 Mar 2017 [0089] Once mandrel 505 is landed, locking screws 605 are used to secure the mandrel 505 to the wellhead 110. Once the mandrel is secured, the upper coiled tube 530, the upper slip connector 525, the second cross over connector 520 and the CARSAC connector 515 are removed, along with the BOP 120 and a master valve 610 of the wellhead 110, as illustrated in Figure 7.

[0090] A flow tee 805 and a rod-lock 810 are then installed on the wellhead 110 as illustrated in Figure 8.

[0091] Finally, a PCP rotor and rods (not illustrated) are lowered through the coil 115, and a PCP drive head is installed, completing the PCP. The well may then be operated using the PCP, to retrieve coal seam gas, for example, until it needs a work-over.

[0092] A further rod-lock 810 and a BOP table 905 are installed, and a work floor 910 is provided, to enable easy access to the well.

[0093] As mentioned above, the well can be work-overed without killing the well, and this process is described below.

[0094] Initially, the PCP drive head is removed, and the PCP rotor and rods are removed.

An isolation device 1005 is then installed on the wellhead 110, as illustrated in Figure 10.

[0095] In particular, the isolation device 1005 is pushed inside the coil 115, and an isolation member thereof is actuated to form a seal between the isolation member and an inner surface of the spoolable coil 115. The isolation member may be deployed less than 1 m into the spoolable coil. The isolation member may be deployed no further than 50 cm into the spoolable coil, an in particular about 30 cm into the spoolable coil.

[0096] The isolation device 1005 may comprise a working piston located at least partially within a casing and movable bi-directionally within the casing, a first force transfer member associated with a first side of the working piston and adapted to extend at least partially through a first end wall of the casing, and a second force transfer member associated with a second side of the working piston and adapted to extend at least partially through a second end wall of the casing.

[0097] Similarly, the isolation device 1005 may comprise a dart (isolation member), injected into the coil under pressure, and configured to create an effective mechanical seal in the coil at 13 2017100355 28 Mar 2017 the surface. In such case, the dart includes an actuation member movable relative to a body thereof, between a rest condition and a use condition which enables the injection and then activation of sealing elements.

[0098] When the isolation device 1005 is in the rest condition, a sealing portion of the isolation member thereof has a diameter that is no greater than the remainder of a body of the isolation device, and no greater than the inside diameter of the spoolable coil. This ensures that, when the isolation device 1005 is introduced into a spoolable coil, the sealing portion does not prevent the isolation member from moving freely within the spoolable coil.

[0099] The sealing elements may form a seal against the inner surface of the spoolable coil in any suitable manner. For instance, movement of the actuation portion into the use condition may force the sealing portion outwardly from the body into abutment with the inner surface of the spoolable coil. More preferably, however, the sealing portion is fabricated from a deformable material, such that movement of the actuation member results in deformation of the sealing portion, the deformation urging the sealing portion into abutment with the inner surface of the spoolable coil.

[00100] Prior to installing the isolation device 1005, one or more flow tees may be opened to ensure that there is no pressure or flow through the wellhead. If this check reveals that no pressure or flow exists through the wellhead, equipment, such as a well cap, a flow tee, a wellhead penetrator or the like may be removed from the wellhead, if appropriate.

[00101] Once the isolation member has been actuated to form a seal with the inner surface of the spoolable coil, a pressure test is conducted to ensure that sufficient sealing between the isolation member and the inner surface of the coil exists. The pressure test may be conducted at or above wellbore pressure, such as at a pressure of about 1000 psi (6.9 MPa) above wellbore pressure.

[00102] If the seal passes the pressure test, the isolation device 1005 may be separated from the isolation member and withdrawn from the wellhead. In particular, rotation of rotation members of the isolation device 1005 may cause fasteners, such as shear pins, connecting the isolation member to the isolation device 1005 to fracture, thereby disconnecting the isolation member from the isolation device 1005. At this point, the isolation device 1005 may be disconnected and/or withdrawn from the wellhead.

[00103] Alternatively, an upward force may be applied to the isolation device 1005 to fracture the fasteners connecting the isolation device 1005 to the isolation member, while 14 retaining the seal between the isolation member and the inner surface of the spoolable coil. 2017100355 28 Mar 2017 [00104] As illustrated in Figure 11, the flow tee 805 and rod-lock 810 are removed from the wellhead 110, and the CARS AC 515 is installed to the tubing mandrel 505 using the second cross over connector 520.

[00105] The upper slip connector 525 and upper coiled tube 530 are then installed, as illustrated in Figure 12, together with the master valve 610 and BOP 120. The mandrel screws 605 are also unlocked.

[00106] The injector 130 and lubricator 125 are then installed, as illustrated in Figure 13, and the assembly is lifted until the mandrel 505 is about 2m until mandrel is above BOP 120. The BOP pipe slips 210 are then closed, and the injector 130 is further raised to expose the CARSAC connector 515.

[00107] The hanging connectors the then removed, and the coil 115 is installed onto the coil tubing reel unit 140 and rolled up out of the well.

[00108] A new coil assembly may then be installed, as outlined above.

[00109] As such, the spoolable coil 115 is withdrawn from the well under pressure and without killing the well, which has several advantages. In particular, embodiments of the present invention enable live-well completions and work-overs, avoid gas production delays, eliminate the time and water required to kill the well, reduce cost of completions and work-overs, reduce operational cost, increase operational safety and efficiencies, reduce pipe handling and personnel exposure, increase operational speed (RIH/POOH 20-30 m/min), increases operational synergies, enable cost-efficient milling operations (i.e.: stage tool) and under-balance clean-out following drilling rig and/or enable cost-efficient cup-to-cup stimulation treatments following drilling.

[00110] While coiled tubing has previously been used to perform treatments in wellbores (e.g. pumping fluids and chemicals), it has not previously been used in the manner described above. In clear contrast, spoolable coiled tubing has been understood to be inherently unsuitable for such purpose, as it was understood that residual bends would be present in the tubing, and therefore the coil would not be “straight enough” to be used as production string with a conventionally rod driven PCP artificial lift system.

[00111] Moreover, it has also been commonly perceived that a spoolable coil’s resistance to abrasion would make it “too weak” to reasonably withstand the abrasion from the rod-string 2017100355 28 Mar 2017 15 which drives the PCP, thus teaching away from embodiments of the present invention.

[00112] In the present specification and claims (if any), the word ‘comprising’ and its derivatives including ‘comprises’ and ‘comprise’ include each of the stated integers but does not exclude the inclusion of one or more further integers.

[00113] Reference throughout this specification to ‘one embodiment’ or ‘an embodiment’ means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearance of the phrases ‘in one embodiment’ or ‘in an embodiment’ in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more combinations.

[00114] In compliance with the statute, the invention has been described in language more or less specific to structural or methodical features. It is to be understood that the invention is not limited to specific features shown or described since the means herein described comprises preferred forms of putting the invention into effect. The invention is, therefore, claimed in any of its forms or modifications within the proper scope of the appended claims (if any) appropriately interpreted by those skilled in the art.

Claims (5)

1. A method of completing a live well, the method including: introducing, into the well, a spoolable coil, the spoolable coil including a progressive cavity pump (PCP) stator at a lower end thereof; introducing, into the spoolable coil, a PCP rotor; and coupling a PCP drive to the PCP rotor.

2. The method of claim 1, further including: forming a seal against the spoolable coil once the spoolable coil has been introduced to the well.

3. The method of claim 1, further comprising: retrieving the PCP rotor, and withdrawing the spoolable coil from the well without killing the well.

4. The method of claim 3, wherein the step of withdrawing the spoolable coil from the well under pressure includes: installing an isolation device on a wellhead, and actuating the isolation member of the isolation device to form a seal between the isolation member and an inner surface of the spoolable coil.

5. The method of claim 1, further comprising installing a blowout preventer (BOP) onto the well, wherein the spoolable coil is introduced into the well through the BOP.