Pumping system deployment using cable

A technique facilitates rigless deployment of a pumping system, e.g. an electric submersible pumping system, to a desired downhole location. The pumping system is coupled to an electrical cable which is routed through an injector head. The pumping system is supported on the electrical cable and conveyed downhole to the desired position in a wellbore via the injection head. The system and methodology enable deployment of the electrical cable directly through the injector head without coiled tubing.

BACKGROUND

Hydrocarbon fluids such as oil and natural gas are obtained from a subterranean geologic formation, referred to as a reservoir, by drilling a wellbore that penetrates the hydrocarbon-bearing formation. An electric submersible pumping system may be deployed downhole in the wellbore and operated to pump or lift well fluids to a collection location. The electric submersible pumping system often is deployed downhole via coiled tubing which, in turn, is conveyed downhole by a rig and a coiled tubing injector. When a downhole electric submersible pumping system fails, waiting for the rig to be delivered, as well as the rig set up and rig take down, can be very costly and time-consuming.

SUMMARY

In general, a methodology and system are provided to enable a rapid, simple, and cost effective method for deploying a pumping system, e.g. an electric submersible pumping system, to a desired downhole location. The pumping system is coupled to an electrical cable which has been routed through an injector head. The pumping system is supported on the electrical cable and conveyed downhole to the desired position in a wellbore via the injection head. The system and methodology enable deployment of the electrical cable directly through the injector head without coiled tubing and without a rig.

DETAILED DESCRIPTION

The disclosure herein generally involves a methodology and system which facilitate deployment of pumping systems, e.g. electric submersible pumping systems, downhole into a well. A pumping system may be deployed on electrical cable via an injector head, e.g. a coiled tubing injector head, to a desired location along a wellbore. The methodology enables use of the coiled tubing injector head in a manner such that the electrical cable replaces the coiled tubing and is directly injected via the coiled tubing injector head. The pumping system is deployed into the well on an end of the electrical cable.

The methodology further enables deployment of the pumping system without a rig. By supporting the pumping system on electrical cable and by using the injector head to directly inject the electrical cable, the pumping system deployment may be accomplished without incurring the time and expense associated with use of the rig. Thus, when a downhole pumping system fails, the time spent waiting for the rig, as well as the rig set up and rig teardown time, can be avoided. Accordingly, the rigless nature of using the coiled tubing injector head or another suitable injector head increases operational efficiency. By deploying the electrical cable directly through the injector head and without coiled tubing, substantial weight and space savings also are realized, and those savings are of considerable value in offshore deployments and in a variety of other operations.

In an embodiment, the system and methodology may be used to provide a rapid, simple, and cost effective method for deploying an electric submersible pumping system to a desired downhole location. The electric submersible pumping system is coupled to an electrical cable and the cable is routed through an injector head. The electric submersible pumping system is supported on the electrical cable and conveyed downhole to the desired position in a wellbore via the injection head. In this specific example, the system and methodology again enable deployment of the electrical cable directly through a coiled tubing type injector head without coiled tubing and without a rig.

Referring generally toFIG. 1, an example of a system20for deploying a pumping system22is illustrated. In this example, the pumping system22is deployed beneath a wellhead24and moved downhole to a desired location in a wellbore26. The wellhead24is positioned at a surface location28which may be a land surface or a subsea surface. The pumping system22is deployed downhole on an electrical cable30and the electrical cable30is conveyed downhole via an injection head32, such as a coiled tubing injection head, positioned over the wellhead24.

By way of example, the injection head32may be located over wellhead24by an adjustable system34, e.g. a jack stand, a crane, or another suitable system, which is adjustable in height. In a specific example, the injection head32comprises a coiled tubing injection head which is part of an overall coiled tubing injection head system36having a guide arch or goose neck38. The guide arch38is coupled with the injection head32so as to help guide electrical cable30into and through the injection head32when the electrical cable30is used to convey pumping system22downhole into wellbore26. In some applications, the injection head32may be mounted above and separate from the stand34.

In a variety of applications, the pumping system22is in the form of an electric submersible pumping system which may have many types of electric submersible pumping system components. Examples of electric submersible pumping system components include a submersible pump40powered by a submersible motor42. The electric submersible pumping system components also may comprise a pump intake44, a motor protector46, and a system coupling48by which the electric submersible pumping system22is coupled with electrical cable30. In many applications, the submersible motor42may be in the form of a submersible, centrifugal motor and may be operated to pump injection fluids and/or production fluids. In some applications, the pumping system22may comprise an inverted electric submersible pumping system in which the pumping system components are arranged with the submersible pump40below the submersible motor42. However, pumping system22may comprise a variety of pumping systems and pumping system components.

In an operational example, the pumping system22, e.g. the electric submersible pumping system, is coupled to electrical cable30. The electrical cable30is routed through the coiled tubing injector head32and wellhead24. The electrical cable30is thus able to convey the pumping system22to a desired position in wellbore26without the aid of coiled tubing or a rig.

Referring generally toFIG. 2, another embodiment of system20is illustrated. In this embodiment, injector head32is mounted to adjustable system34over wellhead24. If adjustable system34comprises a jack stand, the jack stand34may be adjustable in height via actuators50coupled with a structure52of the jack stand34. For example, stand34may be hydraulically adjustable via hydraulic actuators50which may be operated to raise and lower the height of structure52. In this example, the injector head is a coiled tubing injector head32mounted on structure52. Additionally, a tree assembly54, e.g. a Christmas tree assembly, is coupled to structure52so as to enable movement of both injector head32and tree assembly54to different heights above wellhead24. It should be noted, however, adjustable system34also may be in the form of a crane for use in a crane suspended operation. In this latter embodiment, the adjustable crane34is attached to the injector head32so as to enable raising and lowering of the injector head32and/or tree assembly54.

The tree assembly54may comprise a variety of components depending on the parameters of a given application. By way of example, the tree assembly54may comprise a blowout preventer (BOP)56and a stripper58located above the BOP56. In the example illustrated, the tree assembly54also comprises a cable clamp60, which may be located below the BOP56, and crossover flanges62which may be located below the cable clamp60. Additionally, the tree assembly54may comprise a standoff64which may include a work window66. The standoff64may be located above stripper58and may be used to couple the tree assembly54with the movable structure52of adjustable stand34. Depending on the application, the arrangement of components in tree assembly54may be changed and/or components may be added or removed.

In this embodiment, system20also comprises a hanging spool68which may be positioned above, e.g. on, wellhead24. Additionally, a device70, e.g. a split hanger, may be used between hanging spool68and tree assembly54. In the example illustrated, device70is in the form of a split hanger70having a plurality of hanger components72, e.g. two hanger components72, which can be selectively assembled and disassembled to facilitate deployment of the pumping system22via electrical cable30.

To facilitate deployment of electric submersible pumping system22(or another suitable pumping system), the hanging spool68is constructed with a suitable hanger profile and placed on wellhead24, as illustrated. The tree assembly54is installed onto, e.g. coupled with, the adjustable stand34above the hanging spool68and wellhead24. After the electrical cable30is made up to the pumping system22, e.g. connected with the system coupling48, the split hanger70may be installed. Once the split hanger70is installed, the tree assembly54may be lowered toward the split hanger70and onto the hanging spool68. At this stage, the pumping system22may be run downhole into wellbore26by injecting the electrical cable30via the injector head32. It should be noted the split hanger is only one type of device70, and many devices and methods may be employed for installing the pumping system22. For example, the cable30may be cut and an upper termination may be completed so that a hanger may be attached to the upper termination via work window66. In this example, the entire termination and hanger assembly may then be lowered into the spool hanger68from the work window66.

In the example illustrated, hanging the pumping system22in wellbore26(once pumping system22has been run to the desire downhole position) may be accomplished by utilizing cable clamp60which is capable of holding the entire weight of the pumping system22and electrical cable30. After clamping electrical cable30via cable clamp60, the electrical cable30can be cut to the appropriate seating length. A suitable upper hanging and pack off assembly may then be assembled to the free upper end of the electrical cable30through the standoff64and work window66. The upper hanging and pack off assembly is then reconnected to the portion of electrical cable30(or to another suitable deployment cable) which extends from the injector head32. After the electrical cable30has been reconnected, the cable clamp60may be released.

In this manner, the upper hanging and pack off assembly may be lowered into the split hanger70. Once landed in the split hanger70, the tree assembly54may be disconnected from the setting/hanging spool68and raised via the adjustable stand34. The electrical cable30(or other suitable deployment cable) can then be disconnected from the injector head32to enable removal of the entire tree assembly54and the injector head32. At this stage, the wellhead24can be made ready for production of well fluid via pumping system22.

The procedure for deploying pumping system22downhole to a desired location in wellbore26may vary according to the parameters of a given application, including environmental parameters and the type of equipment employed. An embodiment of a procedure for deploying pumping system22can be performed in stages, as illustrated in the flowcharts ofFIGS. 3-5.

Referring initially toFIG. 3, the procedure comprises initially installing spool hanger68, as represented by block74. In this example, the pumping system22comprises an electric submersible pumping system which is deployed modularly through wellhead24and into wellbore26, as represented by block76. By way of example, the modular deployment of electric submersible pumping system22may be facilitated by attaching a C-clamp to the components of the electric submersible pumping system22for support during assembly.

In this example, another stage of the procedure comprises making up the tree assembly54, as represented by block78inFIG. 4. The coiled tubing injector head32and the tree assembly54are then coupled with adjustable system34, e.g. coupled with a crane or with structure52of an adjustable jack stand, as represented by block80. Once the coiled tubing injector head32is installed, the electrical cable30may be routed through the injector head32and connected to the electric submersible pumping system22via coupling48, as represented by block82. The split hanger70is then installed, as represented by block84, and the height of adjustable system34is reduced. For example, structure52may be lowered via actuators50, e.g. hydraulic actuators, to move tree assembly54downwardly into engagement with spool hanger68, as represented by block86.

This arrangement allows the electric submersible pumping system22to be run downhole into wellbore26via electrical cable30without the use of coiled tubing or a surface rig. As described above, the weight of the electric submersible pumping system22is supported by electrical cable30, and deployment of the electrical cable30is controlled by the coiled tubing injector head32. The coiled tubing injector head32is operated to move the electric submersible pumping system22to, for example, a desired pumping or injection location within wellbore26.

After deployment of the electric submersible pumping system22to the desired downhole location in wellbore26, cable clamp60is closed on electrical cable30, as represented by block88inFIG. 5. The cable clamp60supports the weight of the electric submersible pumping system22and the associated electrical cable30suspended below the cable clamp60. Once clamped by cable clamp60, the electrical cable30can be cut to a desired length above the cable clamp60for installation of a suitable hanging and pack off assembly, as represented by block90. The hanging and pack off assembly may be connected to the electrical cable30at, for example, the coiled tubing injector head32, as represented by block92. For example, the hanging and pack off assembly may be connected to the free upper end of electrical cable30through work window66at standoff64. It should be noted the hanging and pack off assembly may comprise a variety of available or specifically constructed assemblies which support the pumping system22at the wellhead while forming a desired seal with respect to the wellbore26.

The electrical cable30is then reconnected via a suitable connection assembly. For example, the upper end of cable30at the hanging and pack off assembly may be connected to the lower end of electrical cable30extending from coiled tubing injector head32. The cable clamp60is then released and the hanging and pack off assembly is lowered and landed into the split hanger70via injector head32, as represented by block94. Once the hanging assembly has been landed at split hanger70, the tree assembly54may be lifted away from hanging spool68by raising adjustable system34, e.g. raising the crane or raising the structure52, as represented by block96.

Subsequently, the electrical cable30may be disconnected above the hanging spool68and the split hanger70. For example, the cable connection assembly may be uncoupled to disconnect the upper portion of the electrical cable30from the lower portion of the electrical cable30supporting electric submersible pumping system22. This allows the tree assembly54to be removed so as to enable completion of the wellhead for production operations (or other operations), as represented by block98. The methodology described herein enables the electric submersible pumping system22to be placed downhole quickly and efficiently via operation of the coiled tubing injector head32without utilizing coiled tubing or a surface rig.

Depending on the application, the pumping system20may be constructed as an electric submersible pumping system or a variety of other pumping systems. Additionally, the pumping system20may comprise many types of pumping system components having various configurations. The pumping system20also may be powered via electricity received through a variety of electrical cables30having various arrangements of conductors, insulation layers, strengthening members, armor, and/or other components depending on the parameters of the specific application.

Similarly, the wellhead24, injection head32, tree assembly54, spool hanger68, and/or split hanger70may have various components and configurations. For example, the split hanger may be replaced by various other types of hangers or other types of tools. The electrical cable30may be cut, clamped, reconnected, and disconnected via various devices, assemblies and procedures. Additionally, the operational procedure of deploying the pumping system22downhole to a desired location in wellbore26may vary depending on the equipment employed and the parameters of a given deployment operation. The sequence of assembly and disassembly of the various components may be adjusted according to such equipment and/or parameters. In electric submersible pumping system applications, the pumping system22may be constructed for and used in many types of production applications, injection applications, and/or other pumping applications.