Abstract:
A technique facilitates deployment of completion stages downhole in a well environment. A first completion stage is deployed downhole into a wellbore with a plurality of control lines having at least one hydraulic control line and at least one electrical control line. A second completion stage is assembled with an electric submersible pumping assembly and a plurality of corresponding control lines having at least one hydraulic control line and a least one electric control line. The second completion stage is conveyed downhole into the wellbore until engaged with the first completion stage which automatically joins the plurality of control lines. The control lines may then be used to operate both electrical and hydraulic devices of the first completion stage.

Description:
BACKGROUND 
       [0001]    In many well applications, completions are delivered downhole to enable the controlled production of hydrocarbon based fluids. Depending on the environment and the components used in a given completion, the completion system is sometimes delivered downhole in two stages. However, deployment of two or more completion stages can be a difficult and complex procedure, particularly if the initial completion is an intelligent completion. 
       SUMMARY 
       [0002]    In general, the present invention comprises a system and methodology for deploying a plurality of completion stages downhole in a well environment. A first completion stage is deployed downhole into a wellbore with a plurality of control lines having at least one hydraulic control line and at least one electrical control line. A second completion stage is assembled with an electric submersible pumping assembly and a plurality of corresponding control lines having at least one hydraulic control line and a least one electrical control line. The second completion stage is conveyed downhole into the wellbore until engaged with the first completion stage which automatically joins the plurality of control lines. The control lines may then be used to operate both electrical and hydraulic devices of the first completion stage. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0003]    Certain embodiments of the invention will hereafter be described with reference to the accompanying drawings, wherein like reference numerals denote like elements, and: 
           [0004]      FIG. 1  is a front view of a multi-stage completion system deployed in a wellbore, according to an embodiment of the present invention; 
           [0005]      FIG. 2  is a front view of a wet connect system for connecting hydraulic and electrical control lines during the engagement of completion stages, according to an embodiment of the present invention; 
           [0006]      FIG. 3  is a schematic illustration of engagement features of the wet connect system, according to an embodiment of the present invention; and 
           [0007]      FIG. 4  is a front view of another embodiment of the multi-stage completion system deployed in a wellbore, according to an alternate embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0008]    In the following description, numerous details are set forth to provide an understanding of the present invention. However, it will be understood by those of ordinary skill in the art that the present invention may be practiced without these details and that numerous variations or modifications from the described embodiments may be possible. 
         [0009]    The present invention generally relates to a system and method for forming connections between stages of a multi-stage completion. In one embodiment, a completion stage, comprising an electric submersible pumping assembly, is joined downhole with a corresponding completion stage having a plurality of devices, including electrically and hydraulically controlled devices. The devices may be part of an intelligent completion system and/or inflow control completion system in which electric and hydraulic systems are used in the same completion. 
         [0010]    The use of intelligent completion systems and inflow control device completion systems in combination with an electric submersible pumping assembly in a separate completion stage enables optimized production and enhanced recovery of hydrocarbon fluids. Additionally, permanent downhole monitoring systems may be incorporated into the completion system to monitor downhole pressure and temperature to further enhance production optimization. The electric submersible pumping assembly facilitates the production of hydrocarbon fluid, e.g. oil, from wells that are incapable of producing naturally at commercially viable rates. The electric submersible pumping assembly artificially lifts oil to the surface in wells characterized by low reservoir pressure, high water cut, and/or high back pressure from surface facilities. 
         [0011]    Referring generally to  FIG. 1 , one example of a generic well system  20  is illustrated as comprising a wellhead assembly  22 , e.g. a Christmas tree assembly, positioned over a well  24  having a wellbore  26 . A completion  28  is deployed into wellbore  26  via a conveyance  30  which may be in the form of tubing, such as production tubing or coiled tubing. The completion  28  is delivered downhole in a plurality of completion stages. For example, a first or lower completion stage  32  is initially delivered downhole as a tubing string and is represented generally below dashed line  34 . Subsequently, a second or upper completion stage  36  is delivered downhole as a tubing string for engagement with first completion stage  32 . The second completion stage  36  is generally above dashed line  34 . 
         [0012]    In the embodiment illustrated, well  24  is a multilateral well having a generally vertical wellbore section  38 , a main lateral wellbore section  40 , and additional lateral wellbore sections  42  which direct flow of hydrocarbon fluids to the main lateral wellbore  40 . In this example, both vertical wellbore section  38  and lateral wellbore section  40  are cased with casings  44 ,  46 , respectfully. However, completion  28  may be employed in a variety of wells, including cased wells, open hole wells, partially cased wells, vertical wells, inclined wells, horizontal wells, multi-zone wells, and various types of single or multilateral wells. 
         [0013]    Depending on the specific well application, the first completion stage  32  and the second completion stage  36  may be constructed with various arrangements of components. In the example illustrated, first completion stage  32  is an intelligent completion stage with inflow control. The first completion stage  32  is deployed within casing  46  which terminates at a liner shoe  48 . Casing  46  comprises a plurality of openings  50  through which well fluid flows from lateral wellbore sections  42  into main lateral wellbore  40  from a plurality of wells zones. The first completion stage  32  may comprise a plurality of multi-port packers  52  which separate the inflows of well fluid from the different well zones. 
         [0014]    First completion stage  32  also may comprise a plurality of other flow control devices, including a plurality of flow control valves  54 , separated by packers  52 , and a plurality of monitoring systems  56 . The monitoring systems  56  also may be separated by packers  52  to enable monitoring of the fluid inflow from each well zone. The various devices, e.g. flow control valves  54  and monitoring systems  56 , are connected via a combination of control lines including one or more hydraulic control lines  58  and one or more electrical control lines  60 . By way of example, the flow control valves  54  may be controlled by the one or more hydraulic control lines  58 , and the monitoring systems may be coupled to the one or more electrical control lines  60  to receive and/or convey data on monitored production parameters, e.g. temperature and pressure. In some applications, the multi-port packers  52  also may be controlled via inputs from one or more of the control lines  58 ,  60 . Additional and/or alternate powered devices and data providing devices may be incorporated into the first completion stage  32  and coupled with control lines  58 ,  60 . 
         [0015]    Similarly, the second completion stage  36  may comprise a variety of components selected according to the specific environment and production application. In the example illustrated, second completion stage  36  comprises an electric submersible pumping assembly  62  located below a packer  64 , such as a multi-port packer. The electric submersible pumping assembly  62  may comprise a variety of components, such as a submersible pump  66  connected to a pump intake  68 . A submersible motor  70  of the electric submersible pump assembly  62  powers the submersible pump  66  and may have multiple sensors  72 . The second completion stage  36  also may comprise portions of one or more hydraulic control lines  74  and one or more electrical control lines  76  which correspond with hydraulic control lines  58  and electrical control lines  60 , respectively, of first completion stage  32 . The control lines  74 ,  76  serve as hydraulic and electrical supply lines for supplying hydraulic fluid and electricity to the flow control related devices of first completion stage  32 . 
         [0016]    The multi-stage completion  28  also comprises a wet connect system  78 , which is illustrated in enlarged form in  FIG. 2 . The wet connect system  78  comprises a tubing string connector  80  for connecting the tubing strings of first completion stage  32  and second completion stage  36 . By way of example, tubing string connector  80  may comprise a receiver  82 , such as a polished bore receptacle, for receiving a corresponding insert  84  which may comprise a plurality of seals  86  to ensure sealing engagement between the tubing string of second completion stage  36  and the tubing string of first completion stage  32 . In the embodiment illustrated, receiver  82  forms part of first completion stage  32 , and insert  84  forms part of second completion stage  36 . It should be noted, however, that the receiver  82  and insert  84  may be reversed, or tubing string connector  80  may be designed with other types of components capable of forming a sealed connection. 
         [0017]    Wet connect system  78  further comprises a control line connector portion  88  designed to automatically connect hydraulic control line segment  74  with hydraulic control line segment  58  of the first completion stage  32 . Similarly, the control line connector portion  88  automatically connects the electrical control line segment  76  with electric control line segment  60  of the first completion stage  32 . As insert  84  is moved into receiver  82  to connect the tubing strings, the hydraulic control lines and electrical control lines also are simultaneously and automatically connected. Depending on the application, individual or multiple hydraulic lines and individual or multiple electrical lines may be simultaneously connected. 
         [0018]    By way of example, the hydraulic control line  74  and electrical control line  76  extending along second completion stage  36  may have terminations  90 ,  92 , respectively. Additionally, the hydraulic control line  58  and electrical control line  60  of first completion stage  32  may have corresponding terminations  94 ,  96 , respectively. In one example, terminations  90 ,  92  are male terminations and terminations  94 ,  96  are female terminations sized to sealingly receive terminations  90 ,  92 . A plurality of seals  98  may be mounted on male terminations  90 ,  92  to ensure a secure, sealed engagement of the control lines. As the second completion stage  36  is moved downhole into engagement with the first completion stage  32 , wet connect system  78  causes the automatic coupling of both hydraulic control lines and electrical control lines to enable operation of the flow control related devices, e.g. flow control valves  54  and monitoring systems  56 . In other embodiments, the male and female terminations may be reversed, or other types of wet connect components may be employed to form the hydraulic and electrical wet connections in control line connector portion  88 . 
         [0019]    One embodiment of an electrical and hydraulic wet connect system is illustrated in  FIGS. 1-3  as enabling combination of an electric submersible pumping assembly and intelligent completion from separate completion stages. However, the wet connect system  78  may be used to combine hydraulic and electrical control lines in a variety of completion systems in which an electric submersible pumping assembly is located in one stage of a dual stage completion. As illustrated in  FIG. 4 , for example, the first completion stage  32  is deployed in an uncased lateral wellbore  40 . Consequently, the first completion stage  32  combines the upper multi-port packer  52  (located in the cased, vertical wellbore section  38 ) with a plurality of open hole packers  100  positioned in the open hole lateral wellbore  40 . The open hole packers  100  are used to separate the flow control devices, such as flow control valves  54  and monitoring systems  56 . 
         [0020]    Accordingly, well system  20  may be constructed in a variety of configurations for use with many types of wells in many types of environments. The configuration of the lower completion and the upper completion may be adjusted according to the environment and specific well application. The electric submersible pumping assembly may incorporate alternate or additional components. Additionally, redundant electric submersible pumping assembly components may be used in some applications to provide greater pumping capacity. The type and arrangement of packers, monitoring systems, flow control valves, and other flow control devices may be changed. Additionally, the electrical and hydraulic control lines may be coupled with a variety of other types of devices that facilitate control over the inflow of production fluids. The wet connect system also may be adapted according to the specific types of hydraulic control lines and/or electrical control lines utilized in a given application. For example, the electrical control line and hydraulic control line may be routed separately or combined in a single cable. Furthermore, various techniques may be used to control first stage devices and/or to obtain data from the first stage devices via the hydraulic/electrical control lines. 
         [0021]    Although only a few embodiments of the present invention have been described in detail above, those of ordinary skill in the art will readily appreciate that many modifications are possible without materially departing from the teachings of this invention. Accordingly, such modifications are intended to be included within the scope of this invention as defined in the claims.