ELECTRIC GAS LIFT VALVE

Abstract

Electric gas lift valves and systems including a gas lift valve. The gas lift valve may comprise an integrated back check valve and choke valve. The integrated back check valve and choke valve may be retrievable. The gas lift valve may comprise an actuator. The gas lift valve may comprise a fail-closed mechanism comprising a power spring and an electro-magnet that powers a disconnect clutch. The fail-closed mechanism may be configured to close the choke valve in response to a loss of a functionality of the actuator. The gas lift valve may comprise a needle valve that is configured to place the choke valve to vary in an inflow rate. The choke valve may be modular.

Description

BACKGROUND

Field

The present disclosure generally relates to electric gas lift valves.

Description of the Related Art

Oil and gas wells utilize a borehole drilled into the earth and subsequently completed with equipment to facilitate production of desired fluids from a reservoir. Subterranean fluids, such as oil, gas, and water, are produced from the wellbore. In some cases, the fluid is produced to the surface naturally by downhole formation pressures. However, the fluid must often be artificially lifted from wellbores by the introduction of downhole equipment. Various types of artificial lift are available. In a gas lift system, a compressor is located on the surface. The compressor pumps gas down the casing tubing annulus. The gas is then released into the production tubing via gas valves that are strategically placed throughout the production tubing. The gas that is introduced lightens the hydrostatic weight of the fluid in the production tubing, allowing the reservoir pressure to lift the fluid to surface.

SUMMARY

In some configurations, an electric gas lift valve includes an electric actuator, a back check assembly comprising a flow tube and a flapper, and an electro-magnet fail-close mechanism.

The electric gas lift valve can include a variable choke orifice. The electric gas lift valve can include a first pressure sensor configured to read tubing pressure and a second pressure sensor configured to read annulus pressure. The valve can be configured to open or close automatically based on a pressure differential between the first and second pressure sensors.

In some configurations, an electric gas lift valve includes an electric actuator and a variable choke.

The electric gas lift valve can further include a mechanism configured to open and close the valve. The mechanism can be a quarter turn mechanism. The electric actuator can be configured to actuate both opening and closing of the valve, and adjustment of the variable choke. The variable choke can include a nozzle and a venturi, wherein the nozzle is adjustable relative to the venturi to choke flow of gas through the venturi.

BRIEF DESCRIPTION OF THE FIGURES

Certain embodiments, features, aspects, and advantages of the disclosure will hereafter be described with reference to the accompanying drawings, wherein like reference numerals denote like elements. It should be understood that the accompanying figures illustrate the various implementations described herein and are not meant to limit the scope of various technologies described herein.

FIG. 1 illustrates a portion of an example of a gas lift system.

FIGS. 2A and 2B illustrate example existing gas lift valves.

FIGS. 3A and 3B illustrate an example electric gas lift valve according to the present disclosure.

FIG. 4 illustrates a side pocket mandrel according to the present disclosure.

FIG. 5 illustrates another side pocket mandrel according to the present disclosure.

FIG. 6 illustrates an example electric gas lift valve according to the present disclosure.

FIG. 7 an example electric gas lift valve illustrates according to the present disclosure.

FIG. 8 illustrates another side pocket mandrel according to the present disclosure.

FIG. 9 illustrates another side pocket mandrel according to the present disclosure.

FIG. 10 illustrates yet another side pocket mandrel according to the present disclosure.

FIG. 11 illustrates pressure scenarios in another side pocket mandrel according to the present disclosure.

FIG. 12 illustrates other pressure scenarios in another side pocket mandrel according to the present disclosure.

FIGS. 13A and 13B illustrate another side pocket mandrel according to the present disclosure.

FIGS. 14A and 14B illustrate another side pocket mandrel according to the present disclosure.

FIGS. 15A and 15B illustrate another side pocket mandrel according to the present disclosure.

FIGS. 16A and 16B illustrate another side pocket mandrel according to the present disclosure.

DETAILED DESCRIPTION

In the following description, numerous details are set forth to provide an understanding of some embodiments of the present disclosure. It is to be understood that the following disclosure provides many different embodiments, or examples, for implementing different features of various embodiments. Specific examples of components and arrangements are described below to simplify the disclosure. These are, of course, merely examples and are not intended to be limiting. However, it will be understood by those of ordinary skill in the art that the system and/or methodology may be practiced without these details and that numerous variations or modifications from the described embodiments are possible. This description is not to be taken in a limiting sense, but rather made merely for the purpose of describing general principles of the implementations. The scope of the described implementations should be ascertained with reference to the issued claims.

As used herein, the terms “connect”, “connection”, “connected”, “in connection with”, and “connecting” are used to mean “in direct connection with” or “in connection with via one or more elements”; and the term “set” is used to mean “one element” or “more than one element”. Further, the terms “couple”, “coupling”, “coupled”, “coupled together”, and “coupled with” are used to mean “directly coupled together” or “coupled together via one or more elements”. As used herein, the terms “up” and “down”; “upper” and “lower”; “top” and “bottom”; and other like terms indicating relative positions to a given point or element are utilized to more clearly describe some elements. Commonly, these terms relate to a reference point at the surface from which drilling operations are initiated as being the top point and the total depth being the lowest point, wherein the well (e.g., wellbore, borehole) is vertical, horizontal or slanted relative to the surface.

The oil industry has utilized gas lift to produce hydrocarbon or other fluids for decades. In general, a gas lift valve is installed as part of a gas-lift system and aims to control the flow of lift gas into the production tubing conduit. Gas lift systems aid or increase production by injecting high-pressure gas from the casing annulus into fluids that have entered the production tubing from the formation. The injected gas reduces the fluid density and, thus, the hydrostatic pressure of the fluid, allowing in situ reservoir pressure to lift the lightened liquids.

In embodiments, a gas-lift valve is located in the gas-lift mandrel, which also provides communication with the lift gas supply in the tubing annulus. Gas lift valves can be adjusted by operators to control the rate of gas injection into the liquid column in the production tubing. Check valves within the gas lift valves can be used to control the fluid flow in only one direction—from the casing annulus into the production tubing. When the gas flow rate is required to be adjusted due to a new condition of the well, a well intervention operation is required to exchange the orifice size from the gas lift valve.

In embodiments, an electric gas lift valve can be used in a gas lift system. Electricity can be supplied to the valve and be used to actuate the valve in their function remotely, without the need to intervene in the well. In addition, the electric power can enable other functions such as detecting and monitoring the open and close of the valve as well as pressure, temperature, vibration, and flow rates, which are valuable data to the well operator.

FIG. 1 illustrates a downhole portion of an example gas lift system 140. The gas lift system 140 includes a compressor located at the well surface. In use, the compressor pumps gas down the annulus between the casing 102 and the tubing 104, as indicated by arrow 142. The gas is then released into the tubing 104 via one or more gas valves 144 that are strategically placed throughout the tubing 104. The gas lessens the hydrostatic weight of the fluid in the tubing 104, allowing the reservoir pressure to lift the fluid to the surface, as indicated by arrow 146.

FIGS. 2A and 2B illustrate examples of currently available valves 144 that may be used in a gas lift system 140. As shown, the valve 144 includes a check bushing 152, a check dart 154, and a spring (positioned at location 156) disposed in an outer housing 150. The check dart 154 has a hemispherical head 158 and a stem 160 extending away from the head 158. The spring can be disposed about the stem 160. In a closed position, the hemispherical head 158 of the check dart 154 seals against the check bushing 152. The spring can bias the check dart 154 toward the closed position when no pressure is applied to the valve 144. When pressure is applied, e.g., by gas flow along direction 142, the spring is compressed and the check dart 154 moves away from the check bushing 152, thereby opening the valve 144. Flow may be allowed in only one direction—from the annulus into the production tubing 104.

Injection pressure-operated gas lift valves are designed to open in response to a specific gas pressure in the annulus. Traditional backcheck valves use applied pressure and springs to operate. When the pressure in the annulus is high enough to compress the spring, the valve opens. When the pressure is not high enough, the valve closes to prevent flow from the tubing to the annulus.

The present disclosure provides electric gas lift valves, assemblies, systems, and methods. The gas lift valve can be disposed in a side or external pocket of a mandrel coupled to the tubing (e.g., FIG. 9). Electricity is supplied to the gas lift valve. This electric power can be used to actuate the valve to open and/or close. The electric power can also be used by sensors, such as pressure, temperature, vibration, and/or flow sensors. Information provided by the sensors can be valuable data for the well operator. The use of electric power to operate the gas lift valve can advantageously allow for increased reliability and extra functionality.

In some valves, assemblies, systems, and methods according to the present disclosure, the gas lift valve can be opened and/or closed based on data from sensors, such as pressure sensors, instead of a calibrated spring. An electric actuator can move the valve to the open or closed position. In some configurations, the gas lift valve includes a variable choke that allows for fine tuning of the amount of flow through the valve. The gas lift valve can include a flapper with flow tube back check valve. In some configurations, the valve includes an electro-magnet fail-safe mechanism that defaults to closing the valve when the operator does not intentionally want the valve open.

In some configurations, two pressure sensors are used—one sensor measures tubing pressure, and the other measures annulus pressure. The differential pressure measured between the tubing and annulus sensors is used to govern when the valve is opened or closed. The operator can advantageously change the differential pressure settings triggering opening or closing when required or desired. In some configurations, if the sensors read the differential pressure defined to cause closing of the valve, the system automatically closes the valve. In some configurations, a close command is sent to a fail-close mechanism to seal the tubing/annulus instantly or nearly instantly. Various fail-close scenarios are possible. For example, the valve can be designed to be default or biased closed unless and until the operator wants it open. In some scenarios, the operator may want the valve closed even with high annulus pressure. In systems and methods according to the present disclosure, the fail-close mechanism is based on the command of the operator rather than the environment in the well (such as pressure, temperature, and/or flow).

FIGS. 3A and 3B illustrate an electric gas lift. In FIG. 3B, the electric gas lift may comprise a spring 302, below 304, flapper 306, gas entry point 308, venturi 310, check 312, gas exit point 316, open/closed position, ball nut 320, ball screw 324, gearbox 326, motor 328, and resolver/detent brake 330. The resistance temperature detector (RTD) sensor may detect a flow direction and cut power automatically to the fail-safe and close the flapper 306. FIG. 4 illustrates another electric gas lift valve that may comprise a fail-close return spring, one or more stroking bellows 404, variable choke 406, gas entry port 408, gas port exit 410, flapper closure mechanism 412, an actuator stroke 414, electronic cartridge 416, and electric actuator 418. The electronic cartridge 416 may comprise electric motor control and telemetry. FIG. 5 illustrates another electric gas lift valve that may comprise a tubing/annulus pressure gauge 502 and junction box 504. The junction box 504 may be used for electrical connection to one or more electronic boards. FIG. 6 illustrates another electric gas lift valve that may comprise a fail-close return spring 602, stroking bellows 604, gas entry port 606, flow tube to open flapper 608, another portion of the flow tube to open flapper 610, flapper closure mechanism 612, gas exit port 614, secondary sealing mechanism 616, variable choke 618, and production tubing ID 620. FIG. 6 shows the actuation string of the valve when the valve is in the closed position.

FIG. 7 illustrates another electric gas lift valve that may comprise a fail-close return spring (e.g., that may be compressed), gas entry port 706, flapper open 710, gas exit port 714, variable choke 718, production tubing ID 720. FIG. 7 shows the actuation string of the valve when the valve is in the open position. The fail-closed mechanism of any embodiment disclosed in the application may comprise an electro-magnet, collet, and spring assembly that creates a coupling with the actuator. When engaged, the electro-magnet holds the collet in a locked position, compressing a spring. When the electro-magnet releases (e.g., the fail-closed mechanism is disengaged), the spring may push the collet to the unlocked position and may release the coupling. The fail-closed mechanism is used to close the valve.

The gas lift valve may comprise an electric actuator configured to open the valve with desired or required. The actuator can be any type of mechanism that converts electric power to mechanical motion. In the illustrated configuration, the actuator is an electro-mechanical actuator (EMA). The EMA includes an electric motor, gearbox, and ball screw. In use, the actuator engaged the electro-magnet coupling to move the valve to an open position. The actuator opens the flapper mechanism (which seals backpressure). The actuator can then adjust the variable choke to allow more or less flow through the valve.

The orifice size of gas lift valve(s) controls the gas injection rate. In traditional operating valves, orifice size is fixed during installation and cannot be changed during operation. To change the orifice size, for example if needed due to new well conditions, the operating valve must be replaced through intervention. The present disclosure provides a variable choke gas lift valve (e.g., wherein the orifice size may be changed in-situ).

In some configurations, gas lift valves, systems, and methods according to the present disclosure can include a nozzle having an adjustable stroke, a mechanism, e.g., a venturi, that cooperates with the nozzle to choke the passage of gas, and/or a mechanism to open and close the valve to completely interrupt the passage of gas when needed. In some configurations, the mechanism for opening and closing the valve is or includes a quarter turn mechanism. The electric motor can actuate either or both of the open/close mechanism and variable choke. Methods according to the present disclosure can combine both the open/close and variable choke functions to be accomplished by a single electric motor.

FIG. 8 illustrates another electric gas lift valve that may comprise an annulus 800 and production tubing 820. FIG. 8 shows the flow path of gas through the valve from the annulus to the tubing. FIG. 9 illustrates another electric gas lift valve that may comprise an elastomeric seal 902. FIG. 9 discloses how spring force may be used for elastomeric seal friction. The electric gas lift valve may comprise the following attributes: (1) An integrated Back Check Valve and Choke (On-Off) Valve; (2) The integrated unit in point (1) that is retrievable; (3) A choke section that is designed to FAIL CLOSED. With the loss of actuator functionality, the valve may fail in the closed position under the action of a magnetic disconnect clutch and power spring; (4) The on-off choke may be modular and may be placed by a needle valve to vary in the inflow rate. Modular design and interchangeable trim styles may provide chokes with enhanced versatility. Further, the chokes adaptability for various modes of actuation enable for a change of the actuation type in the field without disassembling the choke, minimizing production downtime. A custom spring may be used to meet the desired specifications for the valve. The safety factor, spring pre-load, spring pre-load displacement, spring initial length, spring final length, and spring total force may be calculated accordingly based using data such as seal drag force, hole diameter, shaft diameter, spring free length, plunger travel, spring rate:

TABLE 1
Data:
F    := 130    : Seal drag force
OD    := .75 in: Hole diameter
IDshaft := .375 in: Shaft diameter
Length    := 12 in: Spring free length
Strokevalve := 1.2 in: Plunger travel
k                      spring                                        >=                                                              72                      ⁢                                              lbf                        in
Calculation:
SF := 1.5: Safety factor
Force    := F    · SF = 195 lbf: Spring pre-load
Stroke                                              ?                                                              :=                                                                                            Force                                                      ?                                                                                                    k                          spring                                                                    =                                              2.708                                                in                                                :                                                Spring                        ⁢                                                pre                        -                        load                        ⁢                                                displacement
Spring    := Length    − Stroke    = 9.292 in: Spring initial length
Spring    := Spring    = Stroke    = 8.092 in: Still above the spring solid
height?
Forceheat := (Length    − Spring   ) · k    = 281.4 lbf: Spring total force
indicates data missing or illegible when filed

Target values may be determined for various components of the electric gas lift valve to achieve desired results. For example, different grades (e.g., choice metals, choice materials and/or choice construction used) may be used for the EMA pushing force during normal operation and/or fail close, and retrievability (e.g., metal-to-metal seal force, elastomeric seal friction force, spring force, drag force during opening valve, collet unlatching force and engagement assurance, cam-pack drag force) interface, insertion, flow, back-check, open and close, actuation life cycle, erosion, shelf, port/seat leakage rate. Drag forces during valve opening may be determined based on the interaction between the drive cylinder, collet, and plunger retrievable valve. The size and dimensions of cylinders, collet, plunger, retrievable valve and/or any other elements of the electric gas lift valve may be chosen and/or varied to achieve to reach target values (e.g., actuator force, elastomeric seal). The elements of the valve system may be constructed any combination of materials (e.g., cobalt, cast cobalt alloy 6, K500 Monel 95 KSI YS, Tungsten carbide, Inconel 925/936, 110 KSI, MIN YS liquid nitriding)

FIG. 10 illustrates another electric gas lift valve that may comprise a dog unlatched 1002 and a metal seal 1004. The area, force to provide metal seal, power spring force, maximum stroke, and spring force may be calculated accordingly based using data such as tubing pressure, seal nominal diameter, sealing pressure thickness, spring rate, spring free length, spring solid height:

TABLE 2
Data:
pt := 10 × 103 psi: Tubing pressure
D    := 1.219 in: Seal nominal diameter
t                        max                                                                    ?                                                              :=                                                                  (                                                  1                          64                                                )                                            ⁢                                            in                      :                                            Sealing                      ⁢                                            pressure                      ⁢                                            tickness
k                        spring                                                                    ?                                                              :=                                          72                      ⁢                                              lbf                        in                                            :                                            Spring                      ⁢                                            rate
Free    := 12 in: Spring free length
Solid    := 7.926 in: Spring solid height
Calculation:
A                                              ?                                                              :=                                                                                            x                          -                                                      [                                                                                                                            D                                  2                                                                                                  ?                                                                                            -                                                                                                (                                                                                                            D                                                                              ?                                                                                                              -                                                                          t                                                                              ?                                                                                                                                              )                                                                2                                                                                      ]                                                                          4                                            =                                              0.03                                                                          in                          2                                                :                                                Area
F    := pi · A    = 297.27 lbf: Force to provide metal seal
Fpower    := F    + F    = 557.27 lbf: Power spring force
Strokes1 := Free    − Solid    = 4.074 in: Maximum stroke
F    := k    · Strokes1 = 293.328 · lbf: Spring force
indicates data missing or illegible when filed

If the desired spring force is higher than the calculated spring force, then a custom spring may be used.

FIG. 11 illustrates another electric gas lift valve that may comprise a gas and/or liquid flow path 1102. FIG. 12 illustrates another electric gas lift valve that may comprise a closed position-1^st Barrier 1206 and closed position-2^nd Barrier 1204.

FIG. 13A illustrates a side pocket mandrel 1302. FIG. 13B illustrates a side pocket mandrel that may comprise an Electro-Mechanical Actuator (EMA) 1304, retrievable valve 1306, power spring 1308, plunger 1310, retrievable back-check 1312, and a fail-close spring 1314.

The EMA 1304 may comprise a telemetry multi-chip module (MCM) & firmware and motor control MCM & firmware.

FIG. 14A illustrates a side pocket mandril 1402 comprising a stem 1404 and a linear electric mechanical actuator 1406. FIG. 14B illustrates a dual side pocket mandril having a top and bottom industry thread connection, allowing it to be in line connected with the production string. The dual side pocket mandrel has an internal and an external side pocket to fit valves. Externally to the mandrel there is also the linear electric mechanical actuator and the electronics to control the same.

The valves accommodated in the external pocket may be integral to the mandrel and therefore not retrievable. On the other hand, the valves accommodated in the internal pocket are in common with the production tubing and therefore are retrievable from the mandrel by using wireline tools.

In embodiments, the valve accommodated in the internal side pocket is a retrievable dual back-check valve with an embedded cleaning apparatus.

In embodiments, the valves accommodated in the external side pocket are the flow control valve and the open and close valve. These actuating valves are controlled based on the axial displacement of the stem directly attached to the linear electric mechanical actuator. They are described in more detail in co-pending U.S. provisional patent application No. 63/498,621, the entire content of which is hereby incorporated by reference into the current application.

FIG. 15A illustrates a gas flow path through a valve. The valve may comprise C channel 1502, B channel 1504, A channel 1506, mandril 1508, 1516 double back-check retrievable valve 1516, annulus 1514, ports and/or venturis 1512, gas flow path 1510, governor 1518, and casing 1520. FIG. 15B illustrates the gas flow path through a valve comprising an annulus 1514, tubing 1522, gas flow path 1510, C channel 1502, and b channel 1504. The source of gas available in the annulus reach the multiple entrance ports of the valve. The ports can be open or blinded depending on the position of the governor, as previously explained in the co-pending U.S. provisional patent application No. 63/498,621, the entire content of which is hereby incorporated by reference into the current application. Each port has an individual venturi which limits the amount of gas can get into due to the size of it. The gas reaches the internal diameter of the governor, herein called channel “A” 1506 and goes towards the channel “B” 1504 or channel “C”. In sequence, the gas will flow through the transverse channel “B” or channel “C” 1502 which leads the gas towards the internal pocket where the retrievable double back-check valve with the cleaning apparatus is settled.

FIG. 16A shows a retrievable dual back-check valve with an embedded cleaning apparatus. The valve system may comprise a stem 1610, slide sleeve 1608, 1602 seals, B channel 1604, A channel 1606, mandril 1612, annulus 1614, upper back-check 1616, cleaning apparatus 1618, casing 1620, and lower back-check 1622. In FIG. 16A, the gas may move from the “A” to “B” channel. The gas may go throw the cleaning apparatus upwards and use the downward path of the valve, passing through the lower back-check to reach the tubing. The cleaning apparatus moving upwards will reach the upper back-check and, due to the force of the gas pushing the cleaning apparatus up, in reason of the differential pressure of the injected gas with the tubing zone, makes the cleaning apparatus to scrape off any scale or dust stuck in the sensitive area of sealing.

FIG. 16B shows another retrievable dual back-check valve with an embedded cleaning apparatus. The valve system may comprise an annulus 1614, C channel 1624, cleaning apparatus 1618, cleaning action 1626, upper back-check 1616, and lower back-check 1622. The gas reaches the valve through the channel “B” or “C”, as above mentioned. The element responsible to divert the gas flow from the channel to the another is a slide sleeve. The slide sleeve is settled in the same bore as the governor, also called herein as channel “A”. The slide sleeve is connected to the same actuator stem of the open & close and flow control valve, in such a means part of the stroke of the actuator is dedicated to move that as mentioned slide sleeve. The slide sleeve accommodates some radial seal able to blind the adjacent bore, making sure all the gas will flow through the selected channel.

In FIG. 16B, the gas coming from the “A” to “C” channel, the gas may go throw the cleaning apparatus downward and use the upward path of the valve, passing through the upper back-check to reach the tubing. The cleaning apparatus moving downwards will reach the lower back-check and, due to the force of the gas pushing the cleaning apparatus down, in reason of the differential pressure of the injected gas with the tubing zone, makes the cleaning apparatus to scrape off any scale or dust stuck in the sensitive area of sealing.

The current disclosure provides multiple advantages compared to traditional gas lift valves. For example, the backcheck valve with an embed cleaning device to clean the back-check sealing area improves the sealing capability and resistance against scale and debris. Moreover, the increased system reliability makes the own energy of the lift gas to pilot the cleaning device and clean the valve, instead of embedding more parts to deliver the function.

In this disclosure, numerous details are set forth to provide an understanding of some embodiments of the present disclosure. It is to be understood that the following disclosure provides many different embodiments, or examples, for implementing different features of various embodiments. Specific examples of components and arrangements are described below to simplify the disclosure. These are, of course, merely examples and are not intended to be limiting. However, it will be understood by those of ordinary skill in the art that the system and/or methodology may be practiced without these details and that numerous variations or modifications from the described embodiments are possible. This description is not to be taken in a limiting sense, but rather made merely for the purpose of describing general principles of the implementations. The scope of the described implementations should be ascertained with reference to the issued claims.

As used herein, the terms “connect”, “connection”, “connected”, “in connection with”, and “connecting” are used to mean “in direct connection with” or “in connection with via one or more elements”; and the term “set” is used to mean “one element” or “more than one element”. Further, the terms “couple”, “coupling”, “coupled”, “coupled together”, and “coupled with” are used to mean “directly coupled together” or “coupled together via one or more elements”. As used herein, the terms “up” and “down”; “upper” and “lower”; “top” and “bottom”; and other like terms indicating relative positions to a given point or element are utilized to more clearly describe some elements. Commonly, these terms relate to a reference point at the surface from which drilling operations are initiated as being the top point and the total depth being the lowest point, wherein the well (e.g., wellbore, borehole) is vertical, horizontal or slanted relative to the surface.

Language of degree used herein, such as the terms “approximately,” “about,” “generally,” and “substantially” as used herein represent a value, amount, or characteristic close to the stated value, amount, or characteristic that still performs a desired function or achieves a desired result. For example, the terms “approximately,” “about,” “generally,” and “substantially” may refer to an amount that is within less than 10% of, within less than 5% of, within less than 1% of, within less than 0.1% of, and/or within less than 0.01% of the stated amount. As another example, in certain embodiments, the terms “generally parallel” and “substantially parallel” or “generally perpendicular” and “substantially perpendicular” refer to a value, amount, or characteristic that departs from exactly parallel or perpendicular, respectively, by less than or equal to 15 degrees, 10 degrees, 5 degrees, 3 degrees, 1 degree, or 0.1 degree.

Although a few embodiments of the disclosure 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 disclosure. Accordingly, such modifications are intended to be included within the scope of this disclosure as defined in the claims. It is also contemplated that various combinations or sub-combinations of the specific features and aspects of the embodiments described may be made and still fall within the scope of the disclosure. It should be understood that various features and aspects of the disclosed embodiments can be combined with, or substituted for, one another in order to form varying modes of the embodiments of the disclosure. Thus, it is intended that the scope of the disclosure herein should not be limited by the particular embodiments described above.

Claims

1. An electric gas lift valve comprising: an electric actuator;a back check assembly comprising a flow tube and a flapper; andan electro-magnet fail-close mechanism.

2. The electric gas lift valve of claim 1, further comprising a collet.

3. The electric gas lift valve of claim 1, further comprising a first pressure sensor configured to read tubing pressure and a second pressure sensor configured to read annulus pressure.

4. The electric gas lift valve of claim 1, wherein the valve is configured to open or close automatically based on a pressure differential between the first and second pressure sensors.

5. The electric gas lift valve of claim 1, further comprising a variable choke.

6. The electric gas lift valve of claim 5, further comprising a mechanism configured to open and close the electric gas lift valve.

7. The electric gas lift valve of claim 6, the mechanism comprising a quarter turn mechanism.

8. The electric gas lift valve of claim 5, the electric actuator configured to actuate opening and closing of the electric gas lift valve and adjust the variable choke.

9. The electric gas lift valve of claim 5, wherein the variable choke comprises: a nozzle; anda venturi, wherein the nozzle is adjustable relative to the venturi to choke flow of gas through the venturi.

10. A system for gas lift, the system comprising: an electric gas lift valve;a mandrel; anda cleaning apparatus embedded in the electric gas lift valve.

11. The system of claim 10, wherein the cleaning apparatus is configured to move reciprocally to clean a scale deposit in the gas lift valve.

12. The system of claim 10, further comprising a plurality of openings in the electric gas lift valve, wherein the plurality of openings are configured to be selectively opened or closed to adjust a flow rate through the electric gas lift valve, wherein the plurality of openings are selectively opened or closed by electrical power.

13. The system of claim 12, further comprising an electric mechanical actuator for opening or closing the plurality of openings.

14. A gas lift valve comprising: an integrated back check valve and choke valve, wherein the integrated back check valve and choke valve are retrievable;an actuator;a fail-closed mechanism comprising a power spring and an electro-magnet that powers a disconnect clutch, wherein the fail-closed mechanism is configured to close the choke valve in response to a loss of a functionality of the actuator;a needle valve that is configured to place the choke valve to vary in an inflow rate, wherein the choke valve is modular.

15. The gas lift valve of claim 14, wherein the gas lift valve is an electric gas lift valve.

16. The gas lift valve of claim 14, wherein the actuator is an electro-mechanical actuator comprising an electric motor, a gearbox, and a ball screw.

17. The gas lift valve of claim 14, wherein the fail-closed mechanism further comprises a collet, wherein the electro-magnet, the collet, and the power spring create a coupling with the actuator.

18. The gas lift valve of claim 17, wherein when the fail-closed mechanism is engaged, the electro-magnet is configured to hold the collet in a locked position and compress the power spring, and wherein when the electro-magnet releases, the power spring is configured to push the collet to the unlocked position and release the coupling with the actuator.

19. The gas lift valve of claim 18, wherein when the actuator engages the coupling to move the valve to an open position, the actuator is configured to open a flapper mechanism to seal backpressure.

20. The gas lift valve of claim 14, wherein the choke valve is a variable choke valve, wherein an orifice size of the gas lift valve is configured to be changed in-situ, wherein the actuator is configured to adjust the variable choke valve to allow more or less flow through the gas lift valve.