1. Field of the Invention
The present invention relates to a device for use in producing fluid from a wellbore. More specifically, the invention relates to a system and method for sealing an annular space between a pump and production tubing.
2. Description of the Related Art
Hydrocarbon producing wellbores extend subsurface and intersect subterranean formations where hydrocarbons are trapped. The wellbores are typically lined with casing and have production tubing inserted within the casing. Artificial lift is often relied on for producing hydrocarbons from within a formation when downhole pressure is insufficient for transporting produced liquids to the surface. Typically, artificial lift during oil and gas production uses pumping in the wellbore to lift fluids from downhole to surface and push them to processing facilities. Some pumping systems are integrated with production tubing and conveyed downhole with the production tubing. Other pumping systems are deployed downhole through already installed production tubing and suspended from coiled tubing or power cable.
Through tubing deployed pumping systems require isolation between pump intake and discharge, otherwise fluid exiting the pump can flow back downhole and enter the pump intake and be re-circulated through the pump. An example of an existing isolation technique presets a landing profile (e.g., seal bore) on the tubing. As the pumping system is installed, a seal assembly or seating shoe on the pumping system engages with the landing profile, thus sealing off the fluid path between pump intake and discharge.
It is not uncommon for the pump to be moved to a different depth during the life of the well to compensate for changes in reservoir pressure, water cut or productivity changes and optimize system performance. Changing pump setting depth though requires a workover rig to pull out the tubing and re-install the landing profile at a different depth.
Disclosed herein is an example of a downhole assembly for use in production tubing. In one embodiment the downhole assembly has a pump with a pump inlet and a pump discharge, a motor for driving the pump, and a seal between the pump inlet and pump discharge. In this example the seal is made up of a membrane like member shaped to define an opening facing the pump discharge. When fluid flows from the pump discharge, the discharged fluid enters the opening and urges a portion of the membrane adjacent the opening radially outward so that the membrane fills an annular space between the outer surface of the downhole assembly and production tubing and blocks discharged fluid from entering the pump inlet. Optionally, a lower end of the member distal from the pump discharge is clamped around the outer surface; in this example the member has a stowed position where it is disposed proximate an outer surface of the outer surface. The member is moveable to a deployed position having a cup like shape, wherein an upper end of the member proximate the pump discharge flares radially outward into contact with the tubing. In one alternative, a lower end of the member distal from the pump discharge is clamped around the outer surface and an upper end of the member proximate the pump discharge is secured to the outer surface so that a gap is between the upper end and the outer surface that defines the opening. In this alternate example, a middle portion of the member flares radially outward into contact with the tubing when discharge fluid flows into the opening. An anchoring system may optionally be included with the downhole assembly, where the anchoring system mounts onto an outer surface of the assembly and includes a plurality of anchoring legs. In this example, a portion of each anchoring leg selectively projects radially outward into contact with an inner surface of the tubing. An actuator is optionally mounted on the outer surface that selectively biases against ends of the anchoring legs for projecting the anchoring legs radially outward. In one example, the membrane like member is made up of an annular bladder. In an alternate embodiment, the seal includes a lower bracket that sealingly couples around the outer surface and an upper bracket that circumscribes the outer surface and is set radially outward from the outer surface. Yet further optionally, an upper end of the bladder mounts to the upper bracket and a lower end of the bladder mounts to the lower bracket. In one optional example, the membrane like member has a lower end that pivotingly mounts to the outer surface and an upper end with an outer periphery that defines the opening. Also, folds may be included in the membrane between the lower end and upper end. This embodiment may optionally include rib supports that extend along a path between lower and upper ends of the membrane and coupled with the membrane. Struts may also be included, where each strut has an end pivotingly mounted to an upper bracket that circumscribes the outer surface and a distal end pivotingly coupled to a one of the rib supports.
Also described herein is a wellbore assembly insertable in a tubular disposed in a wellbore. In one example the wellbore assembly includes a pump having a discharge and an annular inlet that depends axially from an end of the pump. A seal assembly is included that circumscribes the annular inlet and that includes; a lower bracket sealingly mounted to an outer surface of the annular inlet, a membrane having a lower end coupled to the lower bracket and an outer periphery that selectively projects radially outward into sealing contact with an inner surface of the tubular. The membrane is radially extended in response to a fluid flowing from the discharge and into a space between the membrane and the annular inlet. The wellbore assembly can further include an upper bracket that circumscribes the annular inlet an axial distance from the lower bracket. In this example an upper end of the membrane is coupled to the upper bracket. In one example, the upper bracket is spaced radially outward from the annular inlet. In one alternate embodiment, the wellbore assembly further includes an anchoring system made up of elongated linkage members disposed at circumferential positions around the annular inlet, upper ends mounted in an upper collar, and lower ends mounted in a lower collar. In this example, an actuator is included for selectively biasing the upper collar towards the lower collar and causing the mid portions of the linkage members to extend radially outward from the annular inlet and into engagement with an inner surface of the tubular. In an example embodiment, the membrane has an elliptical shape when the outer periphery projects radially outward. Optionally, the membrane like member has a lower end that pivotingly mounts to an outer surface of the annular inlet and an upper end with an outer periphery that defines an opening, folds may be included in the membrane that are between the lower end and upper end. Also optionally in the membrane are rib supports extending along a path between lower and upper ends of the membrane and coupled with the membrane. Alternatively, struts may be included that each have an end pivotingly mounted to an upper bracket that circumscribes the outer surface and a distal end pivotingly coupled to a one of the rib supports.
A method of pumping fluid from a wellbore is also disclosed herein. In one example the method includes providing a wellbore assembly that includes a pump having an inlet and a discharge, and a seal assembly. In this example the seal assembly has a toroidally shaped membrane with a lower end sealed against an outer surface of the wellbore assembly and an upper end spaced radially outward from the outer surface to define an opening. The method of this embodiment further includes disposing the wellbore assembly in a tubular in the wellbore and forming a seal between the wellbore assembly and the tubular. The seal is formed by using the pump to pressurize fluid produced from the wellbore, and flowing the pressurized fluid from the discharge to the opening to radially expand the membrane into sealing engagement with the tubular. The method can also include suspending pump operation so the membrane radially retracts from the tubular, moving the wellbore assembly to a different depth in the wellbore, and reforming the seal at the different depth. In one example, the seal isolates fluid produced from the wellbore from fluid being discharged from the pump.
So that the manner in which the above-recited features, aspects and advantages of the invention, as well as others that will become apparent, are attained and can be understood in detail, a more particular description of the invention briefly summarized above may be had by reference to the embodiments thereof that are illustrated in the drawings that form a part of this specification. It is to be noted, however, that the appended drawings illustrate only preferred embodiments of the invention and are, therefore, not to be considered limiting of the invention's scope, for the invention may admit to other equally effective embodiments.
Shown in
An isolation device 32 is shown circumscribing a portion of the annular pump inlet 22. In the embodiment of
Still referring to
Arrows A representing fluid produced from within the wellbore 13 are shown within the tubing 12 and directed towards the opening 23 in the inlet 22. In the configuration of
Referring now to
In an example alternative, operation of the pump 24 can be momentarily suspended while the ESP system 10 is repositioned within the tubing 12 to a different depth. While being repositioned, the barrier 34 can migrate into the stowed configuration of
An axial view of the isolation device 32 is provided in
An example of an actuator 58 is illustrated set above the anchor 48 and is provided for actuating the anchor to retain the ESP system 10A within the tubing 12. The example actuator 58 as shown includes a base 60 with arms 62 that depend axially downward and into contact with the upper collar 52 of the anchor 48. In one example, the base 60 is an annular member that couples on an outer surface of the pump inlet 22A and provides a support for the arms 62 to exert an axial force onto the upper collar 52. Control and power may be provided to the actuator 58 via a line 64 that connects to the power cable 20A. Optionally, a battery (not shown) can be included with the ESP system 10A for powering the system alone or in combination with power delivered via the power line 20A.
Referring now to
Further shown in
Further illustrated in
The present invention described herein, therefore, is well adapted to carry out the objects and attain the ends and advantages mentioned, as well as others inherent therein. While a presently preferred embodiment of the invention has been given for purposes of disclosure, numerous changes exist in the details of procedures for accomplishing the desired results. For example, a locking mechanism can be included to lock the isolation device in place. Also, shear pins may optionally be included to allow unsetting of the isolation device when being pulled. These and other similar modifications will readily suggest themselves to those skilled in the art, and are intended to be encompassed within the spirit of the present invention disclosed herein and the scope of the appended claims.
Number | Date | Country | Kind |
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PCT/US2012/05527 | Sep 2012 | WO | international |
This application claims priority to and the benefit of co-pending U.S. Provisional Application Ser. No. 61/536,778, filed Sep. 20, 2011, the full disclosure of which is hereby incorporated by reference herein.
Number | Name | Date | Kind |
---|---|---|---|
1000583 | Cooper | Aug 1911 | A |
1698444 | Lybyer | Jan 1929 | A |
1757381 | Oliver et al. | May 1930 | A |
1916875 | Yarbrough | Jul 1933 | A |
2103940 | Fletcher | Dec 1937 | A |
2301191 | Boynton | Nov 1942 | A |
2345710 | Lybyer | Apr 1944 | A |
2675080 | Williams | Apr 1954 | A |
3066739 | Saurenman et al. | Dec 1962 | A |
3170520 | Arutunoff | Feb 1965 | A |
3186489 | Farrar et al. | Jun 1965 | A |
3196948 | Dye | Jul 1965 | A |
3411454 | Arutunoff | Nov 1968 | A |
3891031 | Ortiz | Jun 1975 | A |
3939909 | Ortiz | Feb 1976 | A |
4246964 | Brandell | Jan 1981 | A |
4928771 | Vandevier | May 1990 | A |
5236047 | Pringle et al. | Aug 1993 | A |
5297943 | Martin | Mar 1994 | A |
5404946 | Hess | Apr 1995 | A |
5667015 | Harestad et al. | Sep 1997 | A |
6668925 | Shaw et al. | Dec 2003 | B2 |
6915845 | Leising et al. | Jul 2005 | B2 |
7059410 | Bousche et al. | Jun 2006 | B2 |
7322410 | Vinegar et al. | Jan 2008 | B2 |
7392859 | Mock et al. | Jul 2008 | B2 |
7607497 | Mock et al. | Oct 2009 | B2 |
7617880 | Loughlin | Nov 2009 | B2 |
7621322 | Arnold et al. | Nov 2009 | B2 |
7954563 | Mock et al. | Jun 2011 | B2 |
8397811 | Reid | Mar 2013 | B2 |
8689892 | Noui-Mehidi | Apr 2014 | B2 |
20040069504 | Krueger et al. | Apr 2004 | A1 |
20050161232 | Patel et al. | Jul 2005 | A1 |
20070114019 | Brezinski et al. | May 2007 | A1 |
20090101362 | Loughlin | Apr 2009 | A1 |
20100288493 | Fielder et al. | Nov 2010 | A1 |
20100288501 | Fielder et al. | Nov 2010 | A1 |
20110247831 | Smith et al. | Oct 2011 | A1 |
Entry |
---|
PCT International Search Report and the Written Opinion of the International Searching Authority dated Feb. 17, 2014; International Application No. PCT/US2012/055296; International File Date: Sep. 14, 2012. |
Number | Date | Country | |
---|---|---|---|
20130068311 A1 | Mar 2013 | US |
Number | Date | Country | |
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61536778 | Sep 2011 | US |