Patent ID: 12247469

DETAILED DESCRIPTION

FIG.1is a schematic diagram of an example implementation of a downhole pumping system10including a downhole pump assembly100. Generally,FIG.1illustrates at least a portion of one implementation of the downhole pumping system10according to the present disclosure in which the downhole pump assembly100may be run into a wellbore20on a wellbore tubular45(for example, a production string45) within the wellbore20. In this example, an uphole end of the downhole pump assembly100is coupled to the production string45while the downhole pump assembly100is positioned adjacent a subterranean reservoir40.

In this example implementation, the downhole pump assembly100comprises an electric submersible pump (ESP)100(a portion of which is shown inFIG.2) that is operable to circulate a wellbore fluid65, such as a hydrocarbon fluid (for example, oil, gas, or a mixture thereof) from the subterranean reservoir40to a terranean surface12(as described in more detail with reference toFIG.2). In some aspects, the ESP100, as shown, is positioned on the production string45below a wellbore seal80(for example, a packer or other seal) that is positioned in the wellbore20. An annulus50is defined between the production string45and the wellbore20.

As described more fully with reference toFIG.2, in some aspects, the ESP100can be configured to have an extended operational life, as well as minimize shutdowns to maintain production of the wellbore fluid65from the subterranean reservoir40to the terranean surface12. For example, one or more shape members can be integrated with, attached to, or made a part of one or more internal or external pump surfaces. The one or more shape members, in some aspects, can be made of a shape memory material (SMM) that exhibits shape memory effect (SME) as well as other properties, such as corrosion resistance and superelasticity. Examples of SMMs include shape memory alloy (SMA) and shape memory polymer (SMP). A shape of a SMM can change, for example, based on pressure or temperature of a material in contact with or applied to the SMM. In some cases, a wellbore fluid that is circulated by the ESP100can act as the material that adjusts a shape of one or more of the shape members.

As shown, the downhole pumping system10accesses the subterranean formation40and provides access to hydrocarbons (for example, the wellbore fluid65) located in such subterranean formation40. In an example implementation of system10, the system10may be used for a production operation in which the hydrocarbons may be produced from the subterranean formation40through the downhole pump assembly100and to the wellbore tubular45(for example, as a production tubing or casing) uphole of the downhole pump assembly100. The tubular45may represent any tubular member positioned in the wellbore20such as, for example, coiled tubing, any type of casing, a liner or lining, a work string (in other words, multiple tubulars threaded together), or other form of tubular member.

A drilling assembly (not shown) may be used to form the wellbore20extending from the terranean surface12and through one or more geological formations in the Earth. One or more subterranean formations, such as subterranean zone40, are located under the terranean surface12. One or more wellbore casings, such as a conductor casing25, a surface casing30, and an intermediate casing35, may be installed in at least a portion of the wellbore20. Any of the illustrated casings, as well as other casings that may be present in the downhole pumping system10, may include one or more casing collars.

In some implementations, a drilling assembly used to form the wellbore20may be deployed on a body of water rather than the terranean surface12. For instance, in some implementations, the terranean surface12may be an ocean, gulf, sea, or any other body of water under which hydrocarbon-bearing formations may be found. In short, reference to the terranean surface12includes both land and water surfaces and contemplates forming and developing one or more downhole pumping systems10from either or both locations.

Additionally, in some implementations, the wellbore20may be offset from vertical (for example, a slant wellbore). Even further, in some implementations, the wellbore20may be a stepped wellbore, such that a portion is drilled vertically downward and then curved to a substantially horizontal wellbore portion. Additional substantially vertical and horizontal wellbore portions may be added according to, for example, the type of terranean surface12, the depth of one or more target subterranean formations, the depth of one or more productive subterranean formations, or other criteria.

In this example implementation of the downhole pumping system10, the downhole pump assembly100includes a pump110coupled to an electric motor105(for example, that collectively form the ESP100). In this example, the wellbore seal80is set just uphole of one or more perforations55(for example, made in a casing of the wellbore20) that fluidly couple the subterranean reservoir40to the wellbore20. The electric motor105can be operated by electric power provided by power cable70(that extends within the annulus50to electrically connect with the motor105). Upon activation, for example by the power supply system60, the electric motor105activates the pump110to circulate the wellbore fluid65through the perforations55, into one or more inlets of the pump110, and into the production string45toward the terranean surface12as shown.

FIG.2is a schematic diagram of a cross-section of the downhole electrical submersible pump (ESP)100according to the present disclosure. In particular,FIG.2shows a radial stage200of the ESP100, which itself can include multiple radial stages, each of which can be exemplified by the radial stage200. Thus, althoughFIG.2shows a single radial stage200of the ESP100, ESP100includes multiple radial stages200connected in series operation to provide fluid lift to wellbore fluid65in the wellbore.

As shown inFIG.2, the radial stage200includes a housing202that is part of the ESP housing for ESP100. As a radial stage, this radial stage200includes an impeller204and a diffuser206. The impeller204is rotatably driven about axis208(for example, by the ESP motor) to lift a fluid216(for example, liquid or mixed-phase fluid) from a downhole end of the radial stage200(for example, from a previous radial stage in the ESP100) to an uphole end of the radial stage200(for example, to a next radial stage in the ESP100). An eye210of the radial stage200is located adjacent a downthrust washer, and another downthrust washer214is located about a hub205of the radial stage200. An upthrust washer212is also located about the hub205.

As described, one or more shape members can be integrated with, attached to, or made a part of one or more internal or external pump surfaces of the radial stage200. For example, as shown, shape member218is integrated with, attached to, or made a part of an external radial surface209of the diffuser206. In some aspects, shape member218can act to counter a horizontal acting force on the radial stage200. As another example, shape member220is integrated with, attached to, or made a part of an internal radial surface211of the diffuser206. In some aspects, shape member220can act to counter a horizontal acting force on the radial stage200. As a further example, shape member224is integrated with, attached to, or made a part of pump surface215adjacent the upthrust washer212.

In some aspects, shape member224can act to counter an up-thrust force on the radial stage200. Shape member226is integrated with, attached to, or made a part of pump surface213adjacent the downthrust washer214. In some aspects, shape member226can act to counter a down-thrust acting force on the radial stage200. Shape member230is integrated with, attached to, or made a part of an internal radial surface209of the hub205. In some aspects, shape member230can act to counter a horizontal acting force on the radial stage200. Shape members218,220,224,226,228, and230can be made of, for instance, Nitinol (Nickel and Titanium alloy), Copper, Zinc and Aluminum (Cu—Zn—Al) alloys; Copper, Aluminum and Nickel (Cu—Al—Ni) alloys; or Iron, Manganese and Silicon (Fe—Mn—Si) alloys, as examples.

One, some, or all of the shape members218,220,224,226,228, and230can be included in the radial stage200of the ESP100(as well as other radial stages of the ESP100). Additional or alternative shape members can be integrated with, attached to, or made a part of other pump surfaces, such as depending on the operational requirements of the ESP100.

Each shape member218,220,224,226,228, and230can be comprised of or formed of a SMA or SMP and change shape based on a pressure, a temperature, or both, of the fluid216being circulated by the ESP. For example, as the fluid216flows through the radial stage200, a temperature and/or pressure of the fluid216can cause one or more of the shape members218,220,224,226,228, and230to contract. Oppositely, as the fluid216flows through the radial stage200, a temperature and/or pressure of the fluid216can cause one or more of the shape members218,220,224,226,228, and230to expand. Expansion and contraction can cause the radial stage200of the ESP100to operate with different characteristics (for example, head and/or flow rate) relative to a conventional pump radial stage that does not include any of shape members218,220,224,226,228, and230. By providing for this expansion and contraction, the ESP100can remain in operation even during changing well and reservoir parameters and requirements that can include: pressure, temperature, flow rate, fluid composition and wellbore geometry, as the shape members can act to change flow path geometry through the ESP100, as well as through implementation of different force effects that allow the stages to change shape and/or dimension that can lead to extended run life and accommodation of production changes.

Thus, with knowledge of present or future characteristics of the fluid216, one or more shape members218,220,224,226,228, and230can be applied to the radial stage200(and/or other radial stages of ESP100) so that ESP100can operate with multiple operational characteristics: operation with shape members in an initial shape without expansion or contraction; operation with shape members in an expanded shape; and operation with shape members in a contracted shape. In some aspects, one or some of the shape members218,220,224,226,228, and230may be in a contracted shape (or initial shape) during operation while other(s) of the shape members218,220,224,226,228, and230may be in an expanded shape (or initial shape) during operation.

FIG.3is a graph300that shows multiple pump curves of a downhole electrical submersible pump (ESP) according to the present disclosure. For example, graph300shows example pump curves for ESP100including radial stage200as the pump operates in the three operational states: shape members at an initial shape, shape members in a contracted state; and shape members in an expanded state. Graph300includes x-axis302of flow rate (in units of volumetric flow rate, such as gallons per minute or barrels per day) and y-axis304of head (in units of psi or feet lifted).

Pump curve306shows operation of the ESP100with the shape members of radial stage200(or additional radial stages as well) in an initial or original shape (in other words, not contracted nor expanded). Pump curve308shows operation of the ESP100with the shape members of radial stage200(or additional radial stages as well) in a contracted shape. As shown, the ESP100provides lesser performance (lower flow rates at lower heads) as compared to pump curve306. Pump curve310shows operation of the ESP100with the shape members of radial stage200(or additional radial stages as well) in an expanded shape. As shown, the ESP100provides greater performance (higher flow rates at higher heads) as compared to pump curve306. For example, as one or more pump stages expand by expansion of one or more shape members, higher lifting capabilities due to higher flow rate can occur. Alternatively, as one or more pump stages contract by contraction of one or more shape members, lower lifting capabilities due to lower flow rate can occur, where a lower flow rate is entering the pump stage. The expanded pump stage can generate bigger head and higher drawdown, which translates to a higher flow rate.

Graph300shows additional pump characteristics as well. For example, graph300shows a DT limit314, which is a down-thrust limit. Down-thrust is a force that acts on a pump stage where the lifted fluid acts as a downward force on the pump stage. Graph300also shows a UT limit320, which is an up-thrust limit, where the lifted fluids act as an upward force on pump stages. Graph300also shows BEP316, which is a best efficiency point. From an ESP pump curve, the recommended operation range of ESPs (ROR) should be inside the DT limit314and the UT limit320(and more preferably closer to the BEP316) to have the best lifting efficiency and avoid damaging the pump. Operating out of recommended range (below DT limit314or above the UT limit320, can damage the ESP and potentially cause failure if operated out of range for a long time.

The described example implementations of the shape members can re-adjust the DT limit, the UT limit, and the BEP to accommodate different fluid lifting ranges through adjusting limits. The expansion or contraction can be adjusted to cover different lifting rates (e.g., expansion no. 1, 2, 3, etc.) or contraction (no. 1, 2, 3, etc.) where expansion no. 3>2>1 and contraction no. 3<2<1 to cover multiple ranges. This adjustment also occurs with the BEP (no. 1, 2, 3, etc.). Thus, as shown on graph300an adjusted DT limit_2312, an adjusted UT limit_2322, and an adjusted BEP_2318are shown.

The limits can be autonomously adjusted by fluid pressures/temperatures inside wellbore (based on downhole pump sensor values) and/or through user inputs from a surface controller (for example, commands to expand/contract the shape members) by applying pressure/temperature forces to adjust stages. Additional connections (for example, tubing from a pump housing to a surface controller) can be added to allow user input commands (for example, incorporated inside the ESP110inFIG.1).

While this specification contains many specific implementation details, these should not be construed as limitations on the scope of any inventions or of what may be claimed, but rather as descriptions of features specific to particular implementations of particular inventions. Certain features that are described in this specification in the context of separate implementations can also be implemented in combination in a single implementation. Conversely, various features that are described in the context of a single implementation can also be implemented in multiple implementations separately or in any suitable subcombination. Moreover, although features may be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a subcombination or variation of a subcombination.

Similarly, while operations are depicted in the drawings in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Moreover, the separation of various system components in the implementations described above should not be understood as requiring such separation in all implementations, and it should be understood that the described program components and systems can generally be integrated together in a single software product or packaged into multiple software products.

A number of implementations have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the disclosure. For example, example operations, methods, or processes described herein may include more steps or fewer steps than those described. Further, the steps in such example operations, methods, or processes may be performed in different successions than that described or illustrated in the figures. Accordingly, other implementations are within the scope of the following claims.