CN111587312A

CN111587312A - Liner for a wellbore

Info

Publication number: CN111587312A
Application number: CN201780095266.0A
Authority: CN
Inventors: 丹尼尔·牛顿; 丹尼尔·比曼
Original assignee: Abu Dhabi National Oil Co
Current assignee: Abu Dhabi National Oil Co
Priority date: 2017-09-27
Filing date: 2017-09-27
Publication date: 2020-08-25
Also published as: EP3688275A1; EP3688275B1; WO2019064049A1; US20200308937A1; EP3688275A4; MX2020003391A; BR112020006237A2

Abstract

A liner for a wellbore is described, the liner having a sidewall with one or more nozzles formed therein, wherein the one or more nozzles are plugged by a temporary plug. A method of completing an open hole well penetrating a subterranean formation is also described, wherein a liner having a sidewall formed with one or more nozzles is disposed in the well such that the nozzles are in communication with the formation, wherein the one or more nozzles are plugged with a temporary plug.

Description

Liner for a wellbore

Technical Field

The present invention relates to liners for wellbores. The invention also relates to a method of completing a well to replace a non-aqueous fluid with an aqueous fluid using a temporarily plugged nozzle.

Background

Well instability and the resulting loss of production have been studied and methods to limit and reduce such losses have been previously taught. These methods have been applied to oil wells.

European patent No. 2253798 to Nguyen ("Nguyen") teaches a method of stimulating production flow from a formation. The method includes placing an acidic fluid into an area of the subterranean formation to be stimulated to partially dissolve a portion of the area of the subterranean formation. This application discusses the type of acid used in this process and specifically states that a water based acid is most suitable. Once the formation has degraded (to some extent), a consolidating fluid is injected into the formation. The curing fluid is selected from a bonding fluid such as resin composites, tackifiers, and other fluids that cause agglomeration of fine solid particles. The next step includes washing the region with a fluid to remove the coalesced material. The cleaning fluid may be fresh water. Other steps include placing a fracturing fluid into the subterranean zone to create or at least extend a fracture therein.

U.S. patent application No. 2014/0224807 to Ramon ("Ramon") teaches a plug device in which the plug is configured to guide or follow a hardenable material (e.g., cement) pumped through a tubular body. The plug includes one or more portions configured to weaken when exposed to an activating fluid. The material in this case is a controlled electrolytic metal material. The plug further comprises a plurality of plugs nested within one another, wherein the guide plug is in sealing engagement with the wall of the tubular body. The activation fluid used to degrade the electrolytic material may include saline, acid, and aqueous fluids, or combinations thereof. The nested plugs may also include apertures to allow activation fluid to permeate and effectively reach the guide plugs. Weakening of the plug portion specifically includes dissolving one or more pharmaceutical agents.

U.S. patent No. 3,924,677 to Prenner et al ("Prenner") teaches an apparatus for use in the completion of an oil well. The device is a conduit extending through a sidewall of the well casing. The conduit is held in a retracted position in the sidewall from the interior of the casing by a friction sleeve formed of PVC. The opposite end of the conduit is separated to some extent from the external environment by the sacrificial cup. The end of the catheter is sealed with a saline plug, which can shield the fluid. Once the casing is lowered to the desired depth and the cement plug is formed, the outer protective cup (made of cast iron) is broken manually to expose the salt plug in the bore of the conduit. The well casing is scrubbed which will cause the salt plug to dissolve to open the element from both sides. It will be possible to pass between the formation and the interior of the casing.

Aviles et al ("dissolvable plug hole system eliminates burnishing in multi-level stimulation"; Aviles, Isaac; DARDIS, Michael; JACOB, Gregoire; institute of Petroleum Engineers, J. petro., 6 months 2015; "ALVIES") teaches a plug and nozzle device for plugging and perforating a wellbore liner wherein the plug seat is dissolvable. This new method replaces mechanical intervention for removing the stopper. The plug seat assembly is taught for the purpose of acting as a plug and dissolving in a controlled manner after stimulation has been performed. This process will release the ball and leave the full bore inner diameter. In addition, the present disclosure teaches lowering an additional plug seat to seal the nozzle. The plug seat matches the geometry of the container to create a metal-to-metal seal. The ball is then dropped from the surface to land on the plug seat and isolation from the previous zone is completed. The plug seat may dissolve after stimulation, allowing for immediate production.

U.S. patent No. 9,151,143 to Holderman et al ("Holderman") teaches a sacrificial dissolvable plug. The plug is used in series with a flow restrictor disposed in the fluid path between the exterior of the wellbore and the interior of the wellbore. The plug is configured to be at least partially dissolvable upon contact with a fluid. The fluid contains a chemical configured to dissolve the plug.

U.S. patent No. 9,068,429 to Mailand et al ("Mailand") teaches a dissolvable tool formed to include a body having at least one portion configured to dissolve in a fluid. The body comprises a barrier and is movable through a structure, preferably a catheter. The body (and barrier) seals the conduit as the body moves through the conduit. Common techniques for removing such sealing plugs include milling or drilling the sealing plug.

Turning to Prenner, a combination of mechanical and non-intervention techniques is disclosed for removing the plug. The solid and salt plugs are contained within a translating hollow member in a protective well casing. By being solid on the side closest to the inner diameter of the protective sleeve and a salt plug on the opposite side, the hollowness of the member is protected from the effects of the future cementing operation. The sliding member is extended from the protective casing to the wellbore by means of pressure and then cemented in place. After cementing, the solid plug within the hollow member is removed by mechanical means, wherein the downhole assembly comprises a drill bit disposed within the casing. The salt plug inside the hollow member is then exposed to the fluid, which causes the salt plug to dissolve, leaving a hollow conduit connecting the inside of the well casing with the wellbore through the cement. This then allows flow passage from the wellbore through the extended hollow member into the conduit. Therefore, it is known to use a fluid to dissolve the stopper. Prenner does not disclose the use of temporary plugs disposed within nozzles in the sidewall of the liner that do not extend into the wellbore.

Aviles teaches a dissolvable object placed in the path of a catheter. The Aviles disclosure differs from the previously cited application in that the "plug" itself does not dissolve, but rather the plug seat in which the "plug" (ball) is located dissolves. This application provides an alternative method of eliminating flow path blockage through a conduit by dissolving a flow restrictor.

Mailand teaches a body that includes a dissolvable portion and a barrier portion. The barrier portion sealingly engages the interior of the conduit. Much like Aviles, a portion of the flow restricting object is dissolvable to provide a flow path through the conduit.

Turning to Holderman, the disclosure teaches a screen assembly having a sacrificial plug disposed in a sidewall of a conduit and combined with a flow restrictor that operates in series with the sacrificial plug. The sacrificial plug is dissolvable upon contact with the chemical fluid to provide a passageway between the interior and exterior of the wellbore (through the sidewall, flow restrictor and screen assembly). Holderman does not disclose the use of plugs, and nozzles extending through the sidewall of the liner. Holderman also does not disclose the dissolution of the stopper without the use of chemicals. Holderman does not disclose the use of dissolvable plugs without the use of a screen assembly.

Disclosure of Invention

The present application teaches a method for removing a temporary plug fitted to a nozzle in a liner. This method is referred to as non-intervention, which means that no physical intervention (e.g. blasting or firing hardened steel bullets) is used.

Current methods include setting up a work string and then setting up a pre-drilled liner to a final location. Pre-drilling a liner is a special drilling method and requires a lot of time. In addition, the method also requires the deployment of an inner tubular string.

The present application is directed to overcoming the need for a work string and an inner string to replace a plugged nozzle.

To achieve one or more of these objects, the present invention provides a liner for a wellbore, the liner having a sidewall with one or more nozzles formed therein, wherein the one or more nozzles are plugged by a temporary plug. Thus, a liner in the sense of the present invention is a wellbore apparatus, in particular an oil well wellbore apparatus. Such liners can be used as pipes and form conduits. Thus, the sidewall or sheath of the liner is the sidewall of a pipe or catheter and has a proximal end and a distal end such that media can be transported through the liner from the proximal end to the distal end and/or vice versa. The temporary plug is preferably removable by use of a plugging medium which dissolves upon exposure to elevated temperatures and/or an activating fluid, preferably an aqueous fluid. For example, the plugging medium that dissolves in the activating fluid (and particularly in aqueous fluids) may be a salt. In an alternative preferred embodiment, the temporary plug is a mechanical plug that can be removed by applying a pressure cycle. Further preferably, the liner of the present invention includes a liner top packer that isolates the liner top so that all fluid flow passes through the nozzles during operation. It is also preferred that the liner of the present invention comprises a liner shoe and a liner shoe closure, wherein the liner shoe closure allows circulation during a replacement operation and subsequent isolation of the liner shoe. In such a preferred embodiment, the liner shoe closure device may be closed by electronics activated by a timer, Radio Frequency Identification (RFID), pressure, flow, or any combination of these. Alternatively, it may also be closed by a mechanical device using a sleeve mechanically actuated by an intervening device, a dart/ball falling from the surface to mechanically isolate the liner shoe, or a combination of both.

To achieve one or more of the above objects, the present invention also provides a method of completing an open hole well penetrating a subterranean formation, wherein a liner having a sidewall formed with one or more nozzles is disposed in the well such that the nozzles are in communication with the formation, wherein the one or more nozzles are plugged with a temporary plug. Preferably, the liner shoe shut-off valve is arranged to allow displacement of the initial fluid through the liner with plugged nozzles. Further preferably, the temporary plug is removed from the nozzle after positioning the liner.

To achieve the above objectives, the present application also teaches the use of temporary plugs that can be removed by non-physical means or no intervention. This is achieved by using plugs made of a specific material or medium. The medium eventually dissolves, which provides a production flow through the nozzle that is no longer impeded. The dissolution of the plug is due to the nature of the medium and the exposure of this medium to temperature or activating fluid (typically an aqueous fluid). A mechanical plug may be used and removed by applying a pressure cycle.

Drawings

The invention will be described with reference to the accompanying drawings, in which:

FIG. 1 shows a basic case well design with standard nozzles in the liner;

FIG. 2 illustrates a base case well design showing the displacement string required to displace a non-aqueous fluid to an aqueous fluid.

Fig. 3 shows the development of the design from the basic case (left-hand embodiment) to the embodiments according to the invention (middle and right-hand embodiment).

Detailed Description

The present invention relates to the field of oil well drilling, and more particularly to oil well completions and liners for accomplishing such completions. Preferably, the process by which the liner of the present invention may be advantageously used comprises providing a pre-perforated liner having plugged nozzles extending through the perforations. Once the liner is positioned, the temporary plug allows the wellbore to be replaced from non-aqueous fluid to aqueous fluid. The plug is then removed from the nozzle to provide an unobstructed production and jet stream.

Accordingly, the present invention, in one preferred embodiment, teaches a method of completing an open hole penetrating a subterranean formation to control production of oil from the formation and to inject an acidizing fluid into the formation. The well is provided with a nozzle extending through the liner and communicating with the formation. In steady state production conditions, the nozzle provides a negligible pressure drop, while in transient high velocity injection conditions, a sufficient pressure drop is achieved to allow for even distribution of the injected fluid. A temporary plug is located in the nozzle throat so that the nozzle initially serves as a blank for the conduit. A liner shoe shut-off valve is arranged to allow displacement of the primary fluid through the liner with plugged nozzles. A liner with a temporary plug is deployed in a well in a non-aqueous fluid. The temporary plug, in combination with other components, allows for the displacement of non-aqueous fluids through the casing/liner during deployment to help reach the final placement depth. Once the liner is positioned, the temporary plug allows the wellbore to be replaced from non-aqueous fluid to aqueous fluid. The temporary plug is then removed from the nozzle to provide an unobstructed production and injection flow path to the formation and unobstructed interior of the casing/liner for future intervention. Temporary plugs can be removed by a variety of non-intervention methods, such as: temperature dissolving material, aqueous fluid dissolving material, pressure actuated valve. After the aqueous fluid replacement operation, the valve is closed to isolate the shoe and ensure that all future production and injection fluids pass through the nozzle after the temporary plugging mechanism is removed. Once the aqueous fluid displacement operation is completed, a delayed activation liner top packer is set.

Current methods for replacing a pre-drilled liner from a non-aqueous fluid to an aqueous fluid typically require the deployment of a work string after the pre-drilled liner is deployed to a final location. This method requires a significant amount of operating time to manage the work string and make the physical placement within the rig structure.

The pre-drilling of the liner is well-targeted and is performed such that it provides a negligible pressure drop in steady-state production situations, while achieving a sufficient pressure drop in transient high-velocity jetting situations to allow for even distribution of the jetting fluid.

An alternative method for the same replacement operation is to arrange the work string as an inner string within a pre-drilled liner. This method is not suitable for a wide range of applications, as a liner of greater weight cannot be deployed to the final position with increased resistance.

The method according to the invention enables a replacement operation to be performed by pre-drilling the liner without the need for a subsequent work string run or the use of an inner string.

Preferred components that enable this method to be carried out are described below:

liner top packer with delayed activation (until after aqueous fluid displacement). Once set, this packer isolates the liner top to ensure that all fluid flow is through the nozzles.

A liner shoe closure device that allows circulation during a replacement operation, followed by isolation of the shoe for the life of the well. Once isolated, all fluid flow passes through the nozzle. The device may be actuated off by a timer, RFID, pressure or flow activated electronics. Alternatively, the device is closed by a mechanical device using pressure, actuating a dart/ball, or a combination of both.

A temporarily plugged nozzle that is removed once the aqueous fluid replacement operation is completed. Temporary plugs can be removed by using a plugging medium that dissolves over time and is exposed to temperature and/or activating fluid (typically an aqueous fluid) or mechanical plugs that are removed by applying a pressure cycle. The temporary plug must be designed to withstand the pressure differential across the device created by the replacement operation and provide a sufficient time delay to complete the same operation before removal.

The method may be performed using many different temporary plugs. Temporary plugs can be removed by using a plugging medium that dissolves over time and is exposed to temperature and/or activating fluid (typically an aqueous fluid) or mechanical plugs that are removed by applying a pressure cycle. The plug should need to withstand a suitable pressure differential to allow for displacement of the non-aqueous fluid with the aqueous fluid at high velocity. If temperature or activated fluid dissolution methods are used, sufficient delay is required to enable liner deployment in a wide range of applications.

The method saves a lot of operating time and costs over the historical method. In addition, the method allows for cleaning, floating and/or reaming of the pre-drilled liner to full depth in a wide range of applications. The nature of the temporary plugging of the nozzle and the closing shoe and liner top may also allow the liner to be used as a test barrier for upper completion operations.

Claims

1. A liner for a wellbore having a sidewall with one or more nozzles formed therein, wherein the one or more nozzles are plugged with a temporary plug.

2. The liner of claim 1, wherein the temporary plug is removable by use of a plugging medium that dissolves upon exposure to elevated temperature and/or an activating fluid, preferably an aqueous fluid.

3. The liner of claim 1, wherein the temporary plug is a mechanical plug that is removable by applying a pressure cycle.

4. A liner according to any one of claims 1 to 3, comprising a liner top packer which isolates the liner top so that all fluid flow passes through the nozzles during operation.

5. The liner of any one of claims 1 to 4, comprising a liner shoe and a liner shoe closure, wherein the liner shoe closure allows circulation during a replacement operation and subsequent isolation of the liner shoe.

6. The liner of claim 5, wherein the liner shoe closure device is closeable by timer, RFID, pressure or flow activated electronics.

7. The liner of claim 5, wherein the liner shoe closure is closable by a mechanical device using pressure, an actuated dart/ball, or a combination of both.

8. A method of completing an open hole well penetrating a subterranean formation wherein a liner having a sidewall formed with one or more nozzles is disposed in the well such that the nozzles are in communication with the formation, wherein the one or more nozzles are plugged with a temporary plug.

9. The method of claim 8, wherein a liner shoe shut-off valve is arranged to allow displacement of the primary fluid through the liner with plugged nozzles.

10. The method of claim 8 or 9, wherein the temporary plug is removed from the nozzle after the liner is positioned.