In hydrocarbon production wells, it may be beneficial to regulate the flow of formation fluids from a subterranean formation into a wellbore penetrating the same. A variety of reasons or purposes may necessitate such regulation including, for example, prevention of water and/or gas coning, minimizing water and/or gas production, minimizing sand production, maximizing oil production, balancing production from various subterranean zones, and equalizing pressure among various subterranean zones, among others.
A number of devices and valves are available for regulating the flow of formation fluids. Some of these devices may be non-discriminating for different types of formation fluids and may simply function as a “gatekeeper” for regulating access to the interior of a wellbore pipe, such as a production string. Such gatekeeper devices may be simple on/off valves or they may be metered to regulate fluid flow over a continuum of flow rates. Other types of devices for regulating the flow of formation fluids may achieve at least some degree of discrimination between different types of formation fluids. Such devices may include, for example, tubular flow restrictors, nozzle-type flow restrictors, autonomous inflow control devices, non-autonomous inflow control devices, ports, tortuous paths, and combinations thereof.
Reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:
In the drawings and descriptions that follow, like parts are typically marked throughout the specification and drawings with the same reference numerals, respectively. The drawn figures are not necessarily to scale. Certain features of the disclosure may be shown exaggerated in scale or in somewhat schematic form and some details of certain elements may not be shown in the interest of clarity and conciseness. The present disclosure may be implemented in embodiments of different forms.
Specific embodiments are described in detail and are shown in the drawings, with the understanding that the present disclosure is to be considered an exemplification of the principles of the disclosure, and is not intended to limit the disclosure to that illustrated and described herein. It is to be fully recognized that the different teachings of the embodiments discussed herein may be employed separately or in any suitable combination to produce desired results.
Unless otherwise specified, use of the terms “connect,” “engage,” “couple,” “attach,” or any other like term describing an interaction between elements is not meant to limit the interaction to direct interaction between the elements and may also include indirect interaction between the elements described.
Unless otherwise specified, use of the terms “up,” “upper,” “upward,” “uphole,” “upstream,” or other like terms shall be construed as generally toward the surface of the ground; likewise, use of the terms “down,” “lower,” “downward,” “downhole,” or other like terms shall be construed as generally toward the bottom, terminal end of a well, regardless of the wellbore orientation. Use of any one or more of the foregoing terms shall not be construed as denoting positions along a perfectly vertical axis. Unless otherwise specified, use of the term “subterranean formation” shall be construed as encompassing both areas below exposed earth and areas below earth covered by water such as ocean or fresh water.
In the illustrated embodiment, one or more production packers 135, well screens 140, and fluid flow control systems 145 may be interconnected along the production tubing 130. In most systems, there are at least two sets of production packers 135, well screens 140, and fluid flow control systems 145 interconnected along the production tubing 130. The production packers 135 may be configured to seal off an annulus 150 defined between the production tubing 130 and the walls of wellbore 105. As a result, fluids may be produced from multiple intervals of the surrounding subterranean formation 120, in some embodiments via isolated portions of annulus 150 between adjacent pairs of production packers 135. The well screens 140 may be configured to filter fluids flowing into production tubing 130 from annulus 150.
Each of the one or more fluid flow control systems 145, in one or more embodiments, may include a fluid nozzle operable to receive production fluid having a pressure (P3) and discharge control fluid having a control pressure (P2). Further to the embodiment of
Further to the embodiment of
The fluid flow control system 200 may additionally include an inflow control device 230, which in some embodiments may be a pilot valve. The inflow control device 230 may include a production fluid inlet 235 operable to receive the production fluid 210 (e.g., from an annulus 205) having a pressure (P3), a control inlet 240 operable to receive the control fluid 220 having the control pressure (P2) from the fluid nozzle 215, and a production fluid outlet 245 operable to selectively pass the production fluid having the pressure (P1) to the tubing 225. The inflow control device 230, in this embodiment, is thus configured to open or close the production fluid outlet 245 based upon a pressure differential value (P3−P2). The inflow control device 230 is additionally configured to have a pressure drop (P3−P1) across the production fluid inlet 235 and the production fluid outlet 245.
In certain embodiments, the inflow control system 200 additionally includes a turbine 250. The turbine 250, in at least one embodiment, is operable to receive fluid flow from the fluid nozzle 215 and pass (e.g., selectively pass in one embodiment) the control fluid 220 having the control pressure (P2) to the control inlet 240. In certain embodiments, the turbine 250 is operable to selectively pass the control fluid 220 based upon changes in density of the control fluid 220, and thus is a density selective turbine valve. For example, in at least one embodiment, if the turbine 250 senses that the control fluid 220 (e.g., which is representative of the production fluid 210) has a higher concentration of water than oil, the turbine 250 causes the inflow control device 230 to close. Alternatively, if the turbine 250 senses that the control fluid 220 (e.g., which is representative of the production fluid 210) has a higher concentration of oil than water, the turbine 250 causes the inflow control device 230 to open.
The inflow control system 200, in at least one embodiment, introduces a flow regulator 260 coupled to the inflow control device 230. In at least one embodiment, the flow regulator 260 is positioned between the annulus 205 and the inflow control device 230. The flow regulator 260, in one or more embodiments, is configured to regulate a pressure drop (P3−P1) across the production fluid inlet 235 and the production fluid outlet 245. For example, in at least one embodiment, the flow regulator 260 is configured to adjust a flow volume of the production fluid 210 having the pressure (P3) amongst the fluid nozzle 215 and the production fluid inlet 235, for example to regulate the pressure drop (P3−P1) across the production fluid inlet 235 and the production fluid outlet 245. The flow regulator 260, in one or more embodiments, is configured to adjust the flow volume of the production fluid 210 having the pressure (P3), such that the fluid nozzle 215 receives a minimum amount of flow. As the fluid flow control system 200 includes the turbine 250 in at least one embodiment, the flow regulator 260 could adjust the flow volume of the production fluid having the pressure (P3), such that the fluid nozzle 215 receive a minimum amount of flow to keep the turbine 250 spinning.
The flow regulator 260, thus in certain embodiments, is a flow diverter. In yet other embodiments, however, the flow regulator 260 is additionally a flow limiter. For example, certain instances may arise wherein the production fluid 210 having the pressure (P3) is too high for the inflow control device 230. In this scenario, the flow regulator 260 could limit the flow of the higher pressure production fluid 210 to the fluid nozzle 215 and the inflow control device 230. In limiting the flow, the flow regulator 260 could protect the fluid nozzle 215 and the inflow control device 230 from the higher pressure. In at least one embodiment, the limiting of the flow would help reduce erosive effects on either of the fluid nozzle 215 or the inflow control device 230.
In the illustrated embodiment of
As is illustrated, the pressure regulating piston 370 may extend through the production tubing 225 into the annulus 205. Accordingly, the pressure regulating piston 370 may be used to divert the production fluid having the pressure (P3) between the fluid nozzle 215 and the control inlet 235. In at least one embodiment, the flow regulator 360 includes a seal 390 coupled between the regulating piston 370 and the production tubing 225. The seal 390, in accordance with the disclosure, may have a seal area. The seal 390, in the illustrated embodiment, is an O-ring. However, other embodiments exist wherein other types of seals are used. For instance, in another embodiment, the seal 390 is a diaphragm having the seal area. The diaphragm, in one embodiment is a rubber diaphragm, and in another embodiment a metal diaphragm, without limitation. The diaphragm design advantageously eliminates any friction forces associated with the O-ring.
The flow regulator 360 of
In at least one embodiment, the force of the spring member 395 would be equal to the desired pressure drop (P3−P1) across the production fluid inlet 235 and the production fluid outlet 245, multiplied by the aforementioned seal area. Therefore if the pressure drop (P3−P1) across the production fluid inlet 235 and the production fluid outlet 245 exceeds the desired value, the pressure would push the pressure regulating piston 370 to the right, opening up the effective production fluid inlet 235 diameter until the desired pressure drop is achieved. If the pressure drop is below the desired value, the spring member 395 would push the pressure regulating piston 370 to the left further restricting the effective production fluid inlet 235 diameter until the desired pressure drop is achieved.
The spring member 395 is illustrated as being positioned in the production tubing 225. Nevertheless, in at least one other embodiment, the spring member 395 is positioned in the annulus 205. It should further be noted that stops may be added to the flow regulator 360, such that the pressure regulating piston 370 stops when the production fluid inlet 235 is fully open, and/or stops before it is fully closed. In certain other embodiments, as discussed below with regard to
Aspects disclosed herein include:
A. A fluid flow control system, the fluid flow control system including: 1) a fluid nozzle operable to receive production fluid having a pressure (P3) and discharge control fluid having a control pressure (P2); 2) an inflow control device having a production fluid inlet operable to receive the production fluid having the pressure (P3), a control inlet operable to receive the control fluid having the control pressure (P2) from the fluid nozzle, and a production fluid outlet operable to pass the production fluid to the tubing, the inflow control device configured to open or close the production fluid outlet based upon a pressure differential value (P3−P2); and 3) a flow regulator coupled to the inflow control device, the flow regulator configured to regulate a pressure drop (P3−P1) across the production fluid inlet and the production fluid outlet.
B. A well system, the well system including: 1) a wellbore; 2) production tubing positioned within the wellbore, thereby forming an annulus with the wellbore; and 3) a fluid flow control system positioned at least partially within the annulus, the fluid flow control system including; a) a fluid nozzle operable to receive production fluid having a pressure (P3) from the annulus and discharge control fluid having a control pressure (P2); b) an inflow control device having a production fluid inlet operable to receive the production fluid having the pressure (P3), a control inlet operable to receive the control fluid having the control pressure (P2) from the fluid nozzle, and a production fluid outlet operable to pass the production fluid to the production tubing, the inflow control device configured to open or close the production fluid outlet based upon a pressure differential value (P3−P2); and c) a flow regulator positionable between the annulus and the inflow control device, the flow regulator configured to regulate a pressure drop (P3−P1) across the production fluid inlet and the production fluid outlet.
Aspects A and B may have one or more of the following additional elements in combination: Element 1: wherein the flow regulator is configured to adjust a flow volume of the fluid having the pressure (P3) amongst the fluid nozzle and the production fluid inlet to regulate the pressure drop (P3−P1) across the production fluid inlet and the production fluid outlet. Element 2: wherein the flow regulator is configured to adjust the flow volume of the fluid having the pressure (P3) such that the fluid nozzle receives a minimum amount of flow. Element 3: further including a turbine positioned between the fluid nozzle and the control inlet. Element 4: wherein the flow regulator is configured to adjust the flow volume of the fluid having the pressure (P3) such that the fluid nozzle receive a minimum amount of flow to keep the turbine spinning. Element 5: wherein the turbine is a density selective turbine valve. Element 6: wherein the flow regulator is a flow diverter. Element 7: wherein the flow regulator is a flow limiter. Element 8: wherein the flow regulator includes a pressure regulating piston. Element 9: wherein the pressure regulating piston extends through the tubing into the annulus to divert fluid between the fluid nozzle and the control inlet. Element 10: further including a seal coupled between the regulating piston and the tubing. Element 11: wherein the seal is an O-ring. Element 12: wherein the seal is a diaphragm. Element 13: wherein the diaphragm is a rubber diaphragm or a metal diaphragm. Element 14: further including a spring member coupled to the pressure regulating piston, the spring member configured to set a location of the pressure regulating piston relative to the pressure drop (P3−P1). Element 15: wherein the spring member is positioned in the tubing. Element 16: wherein the spring member is positioned in the annulus. Element 17: wherein the flow regulator is configured to adjust a flow volume of the fluid having the pressure (P3) amongst the fluid nozzle and the production fluid inlet to keep the fluid nozzle receiving a minimum amount of flow. Element 18: further including a turbine positioned between the fluid nozzle and the control inlet, and further wherein the flow regulator is configured to adjust the flow volume of the fluid having the pressure (P3) such that the fluid nozzle receive a minimum amount of flow to keep the turbine spinning.
Those skilled in the art to which this application relates will appreciate that other and further additions, deletions, substitutions and modifications may be made to the described embodiments.