BACKGROUND Field

[0001] Embodiments of the present disclosure generally relate to valves for injecting fluid downhole. Particularly, embodiments of the present disclosure relates to tubing mounted injection valve.

Description of the Related Art

[0002] To obtain hydrocarbon fluids from an earth formation, a wellbore is drilled into the earth to intersect an area of interest within a formation. The wellbore may then be "completed" by inserting casing within the wellbore and setting the casing therein using cement, for example. In the alternative, the wellbore may remain uncased (an "open hole" wellbore), or may be only partially cased. Regardless of the form of the wellbore, production tubing is typically run into the wellbore primarily to convey production fluid (e.g. , hydrocarbon fluid, as well as water and other, non- hydrocarbon gases) from the area of interest within the wellbore to the surface of the wellbore.

[0003] Often, pressure within the wellbore is insufficient to cause the production fluid to rise naturally through the production tubing to the surface of the wellbore. Steam or fluid injection, such as water injection, is widely used in maintaining reservoir pressure, enhancing production of hydrocarbon reserves, and reducing the environmental impact. During steam or fluid injection, steam or fluid is injected towards a reservoir from one or more regions of an injection well to assist hydrocarbon recovery from the reservoir by producer wells.

[0004] An injection well generally includes a formation insulation valve located between the wellbore and the reservoir and a tubing mounted injection valve in a tubing upstream to the formation insulation valve. The tubing mounted injection valve is used to facilitate fluid injection to the reservoir through the formation insulation valve. To inject fluid, the formation insulation valve can be opened by pressure cycles through the tubing. However, if the tubing mounted injection valve cannot maintain an open position during the pressure cycles, then the formation isolation valve cannot be opened to inject fluid.

[0005] Therefore, there is a need for improved tubing mounted injection valves. SUMMARY

[0006] Embodiments of the present disclosure generally relate to a tubing mounted injection valve and methods for operating a well using a tubing mounted injection valve.

[0007] One embodiment of the present disclosure provides a valve assembly. The valve assembly includes a valve body, a sleeve movably disposed in the valve body, wherein movement of the sleeve switches the valve assembly between an open position and a closed position, a flow actuator coupled to the sleeve, and a pressure actuator coupled to the sleeve.

[0008] In one embodiment, the flow actuator comprises a housing disposed in an inner diameter of the sleeve, and a flow restrictor disposed in the housing.

[0009] In one embodiment, the pressure actuator comprises a piston disposed in a channel formed in the valve body, wherein the channel has a first end in fluid connection to a port on an outer diameter of the valve body and a second end in fluid connection to a central bore defined by the valve body.

[0010] Another embodiment provides a method for injecting a fluid through a well. The method includes applying an opening pressure to open an injection valve mounted in a tubing hanging in the well. The injection valve includes a sleeve movable to open and close the injection valve, a flow actuator coupled to the sleeve, and a pressure actuator coupled to the sleeve. The method further includes applying pressure cycles to open a formation insolation valve positioned downstream to the injection valve, and injecting a fluid through the injection valve and the formation insolation valve.

[0011] Another embodiment provides an injection well. The injection well includes a lower completion set comprising a formation isolation valve, a tubing hanging in the well and coupled to the lower completing set, and a tubing mounted injection valve disposed in the tubing. The tubing mounted injection valve comprises a valve body mounted in the tubing, a sleeve movably disposed in the valve body, wherein movement of the sleeve switches the tubing mounted injection valve between an open position and a closed position, a flow actuator coupled to the sleeve, and a pressure actuator coupled to the sleeve.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the various aspects, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this disclosure and are therefore not to be considered limiting of its scope, for the disclosure may admit to other equally effective embodiments.

[0013] Figure 1A is a schematic sectional view of a tubing mounted injection valve in a closed position according to one embodiment of the present disclosure.

[0014] Figure 1 B is a schematic sectional view of the tubing mounted injection valve in an open position.

[0015] Figure 1 C is a schematic sectional view of the tubing mounted injection valve in a transitional position.

[0016] Figures 2A-2F are schematic diagrams of a method for operating a well using a tubing mounted injection valve according to one embodiment of the present disclosure.

DETAILED DESCRIPTION

[0017] Embodiments of the present disclosure provide tubing mounted injection valves and methods for operating a well using the tubing mounted injection valves. In one embodiment, an injection valve assembly includes a valve body, a sleeve movably disposed in the valve body, wherein movement of the sleeve switches the valve assembly between an open position and a closed position, a flow actuator coupled to the sleeve, and a pressure actuator coupled to the sleeve. In one embodiment, the injection valve may be activated without using a control line. The injection valve may be held open during run-in to allow fill up. The injection valve may be held open using a pressure actuator while the pressure is cycled to open a formation isolation valve or plug positioned downstream. The injection valve may function as a safety valve after setting the tubing hanger to allow pressure tests of the completion. In one embodiment, the injection valve may be retrievable. In another embodiment, the flow actuator may be retrievable.

[0018] Figure 1A is a schematic sectional view of an exemplary embodiment of an injection valve 100. As shown, the injection valve 100 is mounted on a tubing. In Figure 1A, the injection valve 100 is shown in a closed position. Figure 1 B is a schematic sectional view of the injection valve 100 in an open position.

[0019] The tubing mounted injection valve 100 may be used as a safety valve and flow control valve during injection in an injection well. The tubing mounted injection valve 100 may be opened by either a pressure differential or a flow through a restriction. In one embodiment, the tubing mounted injection valve 100 may be retrievable using a retrieving tool.

[0020] The tubing mounted injection valve 100 includes a tubular valve body 102 which enables the injection valve 100 to be mounted inside a production tubing. Figure 1A schematically shows that the tubular valve body 102 may include an upper tubular 102a and a lower tubular 102b connected together using thread connections. Alternatively, the tubular valve body 102 may include any suitable configurations. In one embodiment, the tubular valve body 102 is configured to be mounted in a tubing. In another embodiment, the tubular valve body 102 may be retrievable from the tubing.

[0021] The tubular valve body 102 has a central bore 106 along a central axis 104. The central bore 106 has an upper opening 106a and a lower opening 106b. A flapper 108 is disposed near the lower opening 106 in the central bore 106. The flapper 108 is pivotably connected to an annular valve seat 1 10 using a pivot joint 1 12. The flapper 108 is biased to a closed position on the annular valve seat 1 10. Alternatively, other closure members, such as a ball and seat valve, may be used in place of the flapper 108 and the valve seat 1 10 to selectively close the central bore 106.

[0022] The injection valve 100 includes an actuator sleeve 1 14 disposed inside the central bore 106. An outer diameter 1 14o of the sleeve is disposed along an inner diameter 102i of the tubular valve body 102. The actuator sleeve 1 14 is movable along the central axis 104 in the central bore 106. A lower end 1 16 of the actuator sleeve 1 14 is configured to interact with the flapper 108 so that the lower end 1 16 may push the flapper 108 towards an open position. An upper end 1 18 of the actuator sleeve 1 14 is coupled to a biasing element 120. In one embodiment, the biasing element 120 may be a coil spring positioned between a shoulder 122 of the tubular valve body 102 and the upper end 1 18 of the actuator sleeve 1 14. The coil spring 120 may be expanded to bias the actuator sleeve 1 14 toward an upper position, as shown in Figure 1A, which allows the flapper 108 to move to a closed position.

[0023] The actuator sleeve 1 14 may be moved within the tubular valve body 102 using a pressure actuator, a flow actuator, or both. The pressure actuator may be operated by the pressure difference between the interior of the injection valve 100 and the exterior of the injection valve 100. The flow actuator may be operated by the flow rate through the injection valve 100.

[0024] The flow actuator may include a housing 124 and a flow restrictor 126. The housing 124 may be attached to the actuator sleeve 1 14. An outer diameter 124o of the housing 124 may be pressed against an inner diameter 1 14i of the actuator sleeve 1 14. During operation, the housing 124 and the actuator sleeve 1 14 move together as one unit. The flow restrictor 126 may be disposed inside the housing 124. In another embodiment, the housing 124 and the flow restrictor 126 may be integrated or the flow restrictor 126 may be attached directly to the sleeve 14. The flow restrictor 126 has a reduce flow area 128 that is smaller than the flow area of the housing 124. When a fluid flows through the reduced flow area 128, the reduced flow area 128 creates a pressure drop across the flow restrictor 126 resulting in an urging force on the housing 124. The urging force may increase until it becomes sufficient to overcome the biasing force of the biasing element 120, thereby moving the housing 124 and the actuator sleeve 1 14 downward to push open the flapper 108 as shown in Figure 1 B. Even though a fixed flow restrictor is shown in Figure 1A, any suitable flow resistors may be disposed in the housing 124 to move the actuator sleeve 1 14. In one embodiment, a variable flow resistor may be disposed in the housing 124 to prevent chattering of the flapper 108 when a flow rate fluctuates. For example, variable nozzle assemblies disclosed in US 2013/0081824A by Hill et al. may be used in place of the flow restrictor 126. In one embodiment, the flow restrictor 126, alone or in combination with the housing 124, may be retrievable using a tool through the tubing. In one embodiment, an interior profile 130 may be formed inside the housing 124 for receiving the retrieval tool.

[0025] The pressure actuator may include a piston 132 disposed in a channel 136 formed through the valve body 102. The piston 132 may be connected to the actuator sleeve 1 14 through an adaptor 134. In one embodiment, the adaptor 134 may be attached to the outer diameter 1 14o of the actuator sleeve 1 14. A first end 136a of the channel 136 may be in fluid communication with the central bore 106 and a second end 136b of the channel 136 may be in fluid communication with an exterior of the valve body 102 via a port 138. When the injection valve 100 is mounted to a tubing, the port 138 is configured to be exposed to the annulus pressure. In this respect, the upper end of the piston 132 is exposed to the tubing pressure, and the lower end is exposed to the annulus pressure. When the interior pressure and the exterior pressure are balanced, the piston 132 is in an upper position in the channel 136 to keep the injection valve 100 in the closed position as shown in Figure 1A. When the interior pressure increases sufficiently to overcome the biasing force from the biasing element 120 and the annulus pressure, the piston 132 moves downward along with the actuator sleeve 1 14 to push the flapper 108 to an open position as shown in Figure 1 B.

[0026] The injection valve 100 may also include an auxiliary sleeve 140 attached to the valve body 102 inside the central bore 106. The actuator sleeve 1 14 may be temporarily attached to the auxiliary sleeve 140 to retain the actuator sleeve 1 14 at the open position. In one embodiment, the actuator sleeve 1 14 may be attached to the auxiliary sleeve 140 using a shearable member such as a shear pin 142. Other suitable methods, such as a burst disk may be used in place of the shear pin 142 to keep the injection valve 100 in an open position. When desired, an exterior pressure may be applied through the port 138 to break the shear pin 142 and close the injection valve 100.

[0027] In Figure 1 B, the injection valve 100 is held open by the shear pin 142. After the shear pins 142 are broken, the open position may be maintained by a pressure inside the injection valve 100, by a fluid flow through the injection valve 100, or the combination of the pressure and the fluid flow. The injection valve 100 stays open when the pressure in the central bore 106 of the injection valve 100 is high enough to overcome the combination of the annulus pressure and the biasing force of the biasing element 120. The injection valve 100 also stays open when a downward fluid flow 144 through the flow restrictor 126 generates a sufficient urging force to overcome the combination of the biasing force of the biasing element 120 and the annulus pressure. The injection valve 100 can also stay open when the combination of higher interior pressure and the urging force from the fluid flow is sufficient to overcome the combination of the biasing force of the biasing element 120 and the annulus pressure through the port 136. Thus, the injection valve 100 can stay in the open position when there is no flow across the flow restrictor 126 as long as the pressure inside the injection valve 100 is high enough. Similarly, the injection valve 100 can also stay open when the pressure across the piston 132 is substantially equal but there is enough fluid flow across the flow restrictor 126. Similarly, the injection valve 100 can remain open by the combination of flow rate and pressure; thus, fluctuations in flow or pressure would not cause chattering of the injection valve 100.

[0028] Figure 1 C is a schematic sectional view of the tubing mounted injection valve 100 in a transitional position from the closed position of Figure 1A to the open position of Figure 1 B. The actuator sleeve 1 14 moves downward so that the lower end 1 16 of the actuator sleeve 1 14 pushes the flapper 108 to the open position. The downward movement of the actuator sleeve 1 14 may be caused by the flow 144 and/or the pressure difference across the piston 132. When both the flow 144 and the pressure difference across the piston 132 cease, the biasing force of the biasing element 120 pushes the upper end 1 18 of the actuator sleeve 1 14 up to close the injection valve 100.

[0029] The tubing mounted injection valve 100 according to the present disclosure may be used with a formation isolation valve to complete an injection well and to inject fluid through the injection well. Figures 2A-2E are schematic diagrams of a method for operating a well using a tubing mounted injection valve, such as the tubing mounted injection valve 100, according to one embodiment of the present disclosure.

[0030] In Figure 2A, a well 200 includes a casing 202 and lower completion assembly having a packer 204 and a formation isolation valve 206. The formation isolation valve 206 may be a safety ball valve. The formation isolation valve 206 is closed, generally by mechanical means, to prevent fluid in a reservoir 208 from entering the well 200. Alternatively, the formation isolation valve 206 may be a plug.

[0031] In Figure 2B, a tubing 210 equipped with a tubing mounted injection valve, such as injection valve 100, is run in hole to the packers 204. During run-in, the tubing mounted injection valve 100 is maintained in an open position to allow the fluid in the casing 202 to fill up the interior 214 of the tubing 210. The injection valve 100 is held open by mechanical devices, such as by a shear pin or a burst disk. The packers 204 seal between the tubing 210 and the casing 202. After run- in, the tubing interior 214 is isolated from the annulus 212.

[0032] In Figure 2C, the tubing 210 is attached to the wellhead by setting the tubing hanger. Then, the tubing mounted injection valve 100 is closed by applying increasing the pressure in the annulus 212. The pressure in the annulus 212 is increased until it is sufficient to the actuator sleeve 1 14break the shear pin 142, thereby allowing the injection valve 100 to return to the closed position. In the closed position, the tubing mounted injection valve 100 acts as a safety valve to prevent fluid in the reservoir 208 from entering to the well 200. At this stage, the tubing mounted injection valve 100 and the formation isolation valve 206 act as two mechanical barriers between the reservoir and the surface. The injection valve 100 and the formation isolation valve 206 allow pressure tests to be performed at this stage.

[0033] After the tubing mounted injection valve 100 is closed, the well 200 may be closed until the time for injection. To start injection, the blow out preventers (BOP) may be removed so that a Christmas tree 218 can be placed on the wellhead. Because both tubing mounted injection valve 100 and the formation isolation valve 206 act as mechanical barriers, it is safe to remove the BOP from the wellhead for Christmas tree installation. For deep water wells, the Christmas tree 216 may be run in on cable from the surface to the ocean floor. In Figure 2C, the Christmas tree 216 is installed on the wellhead and the well 200 is ready for injection.

[0034] To begin injection, the formation isolation valve 206 has to open first. Figures 2D and 2E illustrate a method of opening a formation isolation valve according to one embodiment of the present disclosure. In Figure 2D, an opening pressure may be applied in the tubing interior 214 to open the tubing mounted injection valve 100 by pressure. The opening pressure in the tubing interior 214 is determined by the pressure in the annulus 212 and the biasing force of the biasing element 120 so that the pressure differential between the tubing interior 214 and the annulus 212 is sufficient to overcome the biasing force of the biasing element 120 in the tubing mounted injection valve 100. In another embodiment, the annulus pressure may be reduced so that the pressure differential between the tubing interior 214 and the annulus 212 is sufficient to overcome the biasing force of the biasing element 120. In this respect, the pressure differential will move the piston 132 and the actuator sleeve 1 14 downward to open the flapper 108.

[0035] As shown in Figure 2E, after the tubing mounted injection valve 100 is opened, pressure cycles may be applied through the tubing interior 214 to open the formation isolation valve 206. In one example, about 10 pressure cycles may be applied to the formation isolation valve 206. The pressure cycles may include pulses of a high pressure over a base pressure. The base pressure may be equal to or higher than the opening pressure in Figure 2D so that the tubing mounted injection valve 100 remains open during the pressure cycles even though there is no flow through the injection valve 100. The opening position of the tubing mounted injection valve 100 ensures that the pressure cycles in the tubing interior 214 are applied to the formation isolation valve 206 without any barrier. Because the tubing mounted injection valve 100 according to the present disclosure may be maintained open by pressure alone when there is no flow, embodiments of the present disclosure eliminate pressure trappings between the formation isolation valve and the injection valve in traditional operations.

[0036] In Figure 2F, the formation isolation valve 206 is opened after pressure cycles, and an injection flow 218 is deployed through the tubing 210, the tubing mounted injection valve 100 and the formation insolation valve 206 to the reservoir 208. During injection, the injection flow rate 218 through the flow restrictor 126 is sufficient to generate an urging force to keep the tubing mounted injection valve 100 open. When the injection flow 218 ceases, the tubing mounted injection valve 100 closes and acts as a safety valve.

[0037] While the foregoing is directed to embodiments of the present disclosure, other and further embodiments may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.