Abstract:
The present invention is an intelligent flow control valve which may be inserted into the flow coming out of a pipe and activated to provide a method to stop, measure, and meter flow coming from the open or possibly broken pipe. The intelligent flow control valve may be used to stop the flow while repairs are made. Once repairs have been made, the valve may be removed or used as a control valve to meter the amount of flow from inside the pipe. With the addition of instrumentation, the valve may also be used as a variable area flow meter and flow controller programmed based upon flowing conditions. With robotic additions, the valve may be configured to crawl into a desired pipe location, anchor itself, and activate flow control or metering remotely.

Description:
FEDERAL RESEARCH STATEMENT 
     The invention described herein was made by employees of the United States Government and may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor. 
    
    
     CROSS-REFERENCES TO RELATED APPLICATIONS 
     None. 
     FIELD OF INVENTION 
     The present invention relates to methods and apparatuses for stopping the flow of fluid and more particularly to an intelligent flow control valve. 
     TERMINOLOGY 
     As used herein, the term “anchor assembly” refers to one or more components used to hold and secure an intelligent flow control valve in position in a pipe. 
     As used herein, the term “expansion panel” refers to the pieces which make up the umbrella of an intelligent flow control valve. 
     As used herein, the term “scissor component” refers to a plurality of hinged brace components arranged symmetrically around a threaded component which enables the hinged brace components to be repositioned. For example, hinged brace components may be pushed away from the threaded component when the threaded component is turned one direction and pulled toward the threaded component when the threaded component is turned in the opposite direction. 
     As used herein, the term “throttle” means to increase or decrease the area of an umbrella to decrease or increase the pipe flow area, which controls flow. 
     As used herein, the term “umbrella” refers to an elongated component of a variable area control, component having a variable surface area which may be changed to increase or decrease the flow. 
     As used herein, the term “umbrella control lead screw” refers to a threaded component that is rotated to change the area of an umbrella to alter flow. 
     As used herein, the term “variable area control component” refers to the component of an intelligent flow control valve which is metered to increase or decrease the pipe flow area, changing the delta pressure across the device for different flow rates. 
     BACKGROUND OF THE INVENTION 
     A pipe plug is any type of physical barrier that effectively stops the flow of oil from an oil well or fluid from a pipe. Effective pipe-plugging methods and apparatuses are required in a variety of situations. 
     Many states regulate the plugging of abandoned well structures to confine oil, gas, and water in the strata in which they are found and prevent them from escaping into other strata and destroying wildlife and water and creating other environmental hazards. It is important in these situations to completely and permanently stop the flow. 
     When pipelines are damaged, it is necessary to quickly stop the uncontrolled flow, often without regard to the continuing viability of the pipeline. The Deepwater Horizon oil spill (commonly known as the “BP oil spill”) was the largest oil spill in the history of the petroleum industry. An estimated 53,000 barrels per day (8,400 m 3 /d) escaped from the well just before it was capped, amid an international outcry. Millions of television and Internet viewers watched black plumes of oils spilling into the ocean as the company attempted to inject “dead weight” in the form of heavy liquid and cement and other barriers into the top and bottom of the well. 
     Inserting a device into the escaping flow was difficult or impossible to control and the dead weight did not prevent blow out causing oil escape at other locations. In addition, due to extremely harsh environments (e.g., ocean floor), repairing these pipes is often very difficult. 
     Even more controversial than the escaping oil was the inability to monitor the flow of oil while repairs were being made. 
     Although the Deepwater Horizon oil spill was a well-publicized historic event, damage to pipelines occurs with some regularity and even predictability. Containing the BP spill was the predominant concern without regard to the future viability of the well. Many pipelines, however, must be repaired and placed back into use. 
     Dead weight plugging methods known in the art generally do not seal the pipes completely. In addition, these plugs cannot be removed once they are in place. 
     It is necessary to stop or meter the amount the flow during, and possibly after, the repair process. In addition, the plugging device must be capable of being opened or removed from the pipe once the repairs have been completed. 
     Various plugging methods and apparatuses are disclosed in the art (e.g., U.S. Pat. Nos. 2,646,845, 2,672,200, 2,710,065, 2,969,839, 3,070,163, 3,079,997, and 3,489,216). Invariably, these methods require placement of some type of material (e.g., heavy liquids, gravel, cementitious material, epoxy resin mixture, sealant, drilling mud) to form a solid barrier. These plugging methods and apparatuses are difficult or impossible to remove once the repair has been completed. 
     Typically, the pipe can be placed back into use only if a section of the pipe is cut out and the device removed. In addition, inserting a device that requires back-filling is complicated as constant pressure has to be applied while the back-filling material is drying. 
     The prior art also discloses attempts to create plugs which are mechanically adjustable to allow reuse of pipes after a repair. U.S. Pat. No. 6,241,424 (Bath &#39;424) teaches a plug apparatus which includes a body shaft having an external surface and an internal cavity. A cup seal is mounted to the body shaft and engages an interior wall of the pipeline. The cup seal is roughly the size of the internal pipe. A cam is attached to the external surface of the body shaft and a slip assembly slides on the cam to engage a slip with the interior wall. A control mechanism controls the engagement and release of the slip from the interior wall. The plug taught by Bath &#39;424 is not desirable because the fixed diameter of the cup seal does not allow for metered flow. 
     It is desirable to have a pipe plug which does not require back-filling. 
     It is desirable to have a pipe plug which may be easily removed from the pipe or which allows for flow through after repairs are made. 
     It is further desirable to have a pipe plug which allows for controlled and metered flow. 
     SUMMARY OF THE INVENTION 
     The present invention is an intelligent flow control valve comprised of an anchoring mechanism and a variable area control component. The variable area control component is comprised of a fixed frame; an internal longeron frame comprised of a plurality of tracks attached to the bottom of the fixed frame; a plurality of expansion panels; a plurality of alternating inner hinges and outer hinges which connect the expansion panels to form an umbrella; and a plurality of slide points along the inner hinges where the expansion panels slide along the tracks of*the internal longeron frame. To change the area of the expansion panels, an umbrella control lead screw is rotated in one direction to deploy the expansion panels and in the opposite direction to close the expansion panels. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates a perspective view of an exemplary embodiment of an intelligent flow control valve with variable area control component closed. 
         FIG. 2  illustrates a perspective view of an exemplary embodiment of an intelligent flow control valve with variable area control component fully deployed. 
         FIG. 3  illustrates a perspective view of an exemplary embodiment of an intelligent flow control valve with optional pyrotechnic anchoring mechanisms. 
         FIG. 4  illustrates a bottom view of an exemplary embodiment of a variable area control component closed. 
         FIG. 5  illustrates a bottom view of an exemplary embodiment of a variable area control component fully deployed. 
         FIG. 6  illustrates a perspective view of an exemplary embodiment of a variable area control component closed. 
         FIG. 7  illustrates a perspective view of an exemplary embodiment of a variable area control component fully deployed. 
         FIG. 8  illustrates an exemplary embodiment of an intelligent flow control valve inside a pipe with variable area control component closed. 
         FIG. 9  illustrates an exemplary embodiment of an intelligent flow control valve inside a pipe with the frame secured against the pipe walls and variable area control component fully deployed. 
         FIG. 10  illustrates an exemplary embodiment of a variable area control component used as a variable area flow meter. 
         FIG. 11  illustrates an exemplary embodiment of an intelligent flow control valve for integrating with electronic flow calculation instrumentation. 
     
    
    
     DETAILED DESCRIPTION 
     For the purpose of promoting an understanding of the present invention, references are made in the text to exemplary embodiments of an intelligent flow control valve and variable area flow meter, only some of which are described herein. It should be understood that no limitations on the scope of the invention are intended by describing these exemplary embodiments. One of ordinary skill in the art will readily appreciate that alternate but functionally equivalent materials, components, and designs may be used. The inclusion of additional elements may be deemed readily apparent and obvious to one of ordinary skill in the art. Specific elements disclosed herein are not to be interpreted as limiting, but rather as a basis for the claims and as a representative basis for teaching one of ordinary skill in the art to employ the present invention. 
     It should be understood that the drawings are not necessarily to scale; instead, emphasis has been placed upon illustrating the principles of the invention. In addition, in the embodiments depicted herein, like reference numerals in the various drawings refer to identical or near identical structural elements. 
     Moreover, the terms “substantially” or “approximately” as used herein may be applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. 
       FIG. 1  illustrates a perspective view of an exemplary embodiment of intelligent flow control valve  100 . In the embodiment shown, intelligent flow control valve  100  is comprised of lead screw  10 , umbrella control lead screw  15 , frame  20 , and variable area control component  80 . 
     In the embodiment shown, frame  20  is comprised of a plurality of vertical arms  40  and anchor assemblies  30 ,  60 . Vertical arms  40  provide a rigid framework for anchor assemblies  30 ,  60  and prevent rotation of anchor assemblies  30 ,  60  while intelligent flow control valve  100  is secured inside a pipe. 
     In the embodiment shown, anchor assemblies  30 ,  60  are scissor components comprised of moving collars  32 ,  62 , rigid collars  34 ,  64 , first set of braces  36 ,  66 , and second set of braces  38 ,  68 . Braces  36 ,  66  are hinged at one end to moving collar  32 ,  62 , respectively, and at the other end to vertical arms  40 . Braces  38 ,  68  are hinged at one end to rigid collar  34 ,  64 , respectively, and at the other end to vertical arms  40 . Braces  36  and braces  38  are secured to one end of said vertical arms  40  at a common pivot point and braces  66  and braces  68  are secured to the opposite end of vertical arms  40  at a common pivot point. The angle between braces  36  and braces  38  at the pivot point and between braces  66  and braces  68  at the pivot point increases or decreases as the distance between moving collar  32  and rigid collar  34  and moving collar  62  and rigid collar  64  changes. 
     Moving collars  32 ,  62  and rigid collars  34 ,  64  encircle lead screw  10 , which is threaded. Rigid collars  34 ,  64  are fixed in position on lead screw  10  while moving collars  32 ,  62  move when lead screw  10  is turned. In an exemplary embodiment, lead screw  10  has both left-handed and right-handed threads, allowing moving collars  32 ,  62  to move toward rigid collars  34 ,  64  when lead screw  10  is rotated in one direction and away from rigid collars  34 ,  64  when lead screw  10  is rotated in the opposite direction. For example, moving collars  32 ,  62  and the portions of lead screw  10  around moving collars  32 ,  62  may have left-handed threads while rigid collars  34 ,  64  and the portions of lead screw  10  surrounding rigid collars  34 ,  64  may have right-handed threads. 
     When lead screw  10  is rotated so that moving collars  32 ,  62  move toward rigid collars  34 ,  64 , the angle between braces  36  and braces  38  and the angle between braces  66  and braces  68  decreases and vertical members  40  are pushed away from lead screw  10  toward to the pipe wall to anchor frame  20  and intelligent flow control valve  100  inside the pipe. 
     To pull vertical members  40  and frame  20  off of the pipe wall, that is, to remove intelligent flow control valve  100  from inside the pipe, lead screw  10  is rotated in the opposite direction, causing moving collars  32 ,  62  to move away from rigid collars  34 ,  64 . When moving collars  32 ,  62  are moved away from rigid collars  34 ,  64 , the angle between braces  36  and braces  38  and the angle between braces  66  and braces  68  increases and vertical members  40  move closer to lead screw  10  and away from the pipe wall. 
     In the embodiment shown, frame  20  includes four vertical arms  40  and each set of braces  36 ,  38 ,  66 ,  68  has four braces. The vertical arms and braces are arranged around lead screw  10  so that intelligent flow control valve  100  is symmetrical, ensuring that the device self-centers when inserted into a pipe. 
     In the embodiment shown, variable area control component  80  is comprised of a fixed frame  70 , ring  75 , internal longeron frame  82 , and a plurality of expansion panels  84 . Fixed frame  70  and ring  75  add strength to variable area control component  80 , allowing variable area control component  80  to withstand high-pressure flow and eliminating the need for back-filling. Internal longeron frame  82  flairs out expansion panels  84 , creating a curved chamber to fit against the pipe wall and further strengthening variable area control component  80 . 
     In the embodiment shown, fixed frame  70 , ring  75 , and internal longeron frame  82  are comprised of heavy steel and internal longeron frame  82  is coated with polytetrafluoroethylene; however, in various other embodiments, may be comprised of another materials and/or coatings. In various other embodiments, ring  75  may be omitted. 
     In the embodiment shown, variable area control component  80  is cone-shaped and includes eight expansion panels  84  and internal longeron frame  82  has four tracks. Expansion panels  84  are hinged together, creating a plurality of inner hinges  92  and outer hinges  94  when variable area control component  80  is closed or partially deployed. 
     Material is removed from the outer edge of expansion panels  84  where outer hinges  94  are positioned, creating clearance cut-outs  96 . Without clearance cut-outs  96 , the edges of expansion panels  84  on outer hinges  92  would protrude past ring  75 , preventing ring  75  of variable area control component  80  from fitting against the pipe wall and/or preventing expansion panels  84  from opening and closing. 
     In various other embodiments, the number of expansion panels  84  and tracks of internal longeron frame  82  may vary. For example, variable area control component  80  may be comprised of sixteen expansion panels with an eight track internal longeron frame (i.e., factor of two). In various embodiments, the depth of variable area control component  80 , the placement of inner hinges  92  and outer hinges  94  may also vary to change the folded area and shape of variable area control component  80 . 
     To change the area of expansion panels  84 , umbrella control lead screw  15 , is rotated in one direction to deploy expansion panels  80  and in the opposite direction to close expansion panels  80 . When umbrella control lead screw  15  is rotated to deploy expansion panels  84 , fixed frame  70 , ring  75 , and internal longeron frame  82  slides downward along slide points  86  (see  FIGS. 6 and 7 ), pushing out expansion panels  84 . When variable area control component  80  is fully deployed, expansion panels  84  rest against the tracks of internal longeron frame  82 . 
     To decrease the area of expansion panels  84 , that is, to partially or completely close variable area control component  80 , umbrella control lead screw  15  is rotated in the opposite direction, causing fixed frame  70 , ring  75 , and internal longeron frame  82  to slide away from expansion panels  84  along slide points  96 , retracting expansion panels  84  to increase flow. Increasing flow reduces the pressure across the variable area control component and decreasing flow increases the pressure across the variable area control component. 
     In the embodiment shown, the tracks of internal longeron frame  82  are positioned at a 45 degree angle to the spokes of fixed frame  70  to maximize the strength of internal longeron frame  82 , allowing variable area control component to withstand high pressure. 
     The dimensions of the components of variable area control component  80  and intelligent flow control valve  100  vary with the area of the pipe into which intelligent flow control valve  100  is to be inserted and whether it is used as a pipe plug, a flow meter, a flow controller, or combinations thereof. For example, for a pipe having a three inch diameter, intelligent flow control valve  100  has a length ranging from 12 to 18 inches with variable area control component  80  having a length of approximately 6 inches. 
     The design of variable area control component  80  allows the pipe open area to be changed, resulting in a variable area control and the ability to throttle, meter, and control gas or fluid flow. The pointed shape of variable area control component  80  allows for easy insertion into a flowing pipe with minimal resistance. The configuration of frame  20  and the cone shape of variable area control component  80  results in a strong device capable of with-standing high pressures and forces. 
     In addition, intelligent flow control valve  100  may further include instrumentation, allowing intelligent flow control valve  100  to be used as a differential head flow meter by adjusting the area of variable area control component  80  in response to different flowing conditions to enhance flow metering accuracy, control pressures losses, or control flows in a closed loop using feedback from the differential pressure across the device. In addition, using measured values from different flow areas enables estimation of fluid properties such as density and viscosity. 
     In various embodiments, intelligent flow control valve  100  may further include an optional robotic crawling mechanism for carrying intelligent flow control valve  100  deep into a pipe. In an exemplary embodiment, optional robotic crawling mechanism would include a motor for turning the lead screws. 
     In the embodiment shown, all components are designed for low drag in fluid. 
       FIG. 2  illustrates a perspective view of an exemplary embodiment of intelligent flow control valve  100  with variable area control component  80  in the deployed position. In the embodiment shown, the tops of expansion panels  84  are positioned just below ring  75 . 
     Also visible in  FIG. 2  is pressure sensor port  95  for measuring the pressure of the flow across variable area control component  80 . 
       FIG. 3  illustrates a perspective view of an exemplary embodiment of intelligent flow control valve  100  with optional pyrotechnic anchoring mechanisms  50  attached to vertical arms  40 . 
     Intelligent flow control valve  100  is inserted into the pipe so that anchoring components  50  are pointed in the direction of pipe flow. In the embodiment shown, pyrotechnic anchoring components  50  are spear devices with pyrotechnic charged spikes  55  which are fired to securely anchor intelligent flow control valve  100  inside a pipe. 
     In an exemplary embodiment, pyrotechnic anchoring components  50  include an ignition wire, a pyrotechnic charge, and a spring-loaded latch. Firing pyrotechnic anchoring components  50  drives spikes  55  into the pipe wall, permanently securing intelligent flow control valve  100  inside the pipe. In various other embodiments, spikes  55  may be replaced with another component, such as a barb. 
     In the embodiment shown, spikes  55  contain tungsten carbide or depleted uranium, which may aid in metal fusion when spikes  55  are driven into the pipe wall. When intelligent flow control valve  100  is anchored inside the pipe, variable area control component  80  can be opened in the pipe to throttle the oil flow. 
     In the embodiment shown, intelligent flow control valve  100  includes eight pyrotechnic anchoring components  50 , two on each vertical arm  40 ; however, in various other embodiments, intelligent flow control valve  100  may include any number of pyrotechnic anchoring components. In various embodiments, one or more components scissor components, pyrotechnic charged spikes which are fired into the pipe wall, spring-loaded arms, external dead weight, permanent spikes pushed into the pipe wall via a lever or scissor motion, any other holding device, and combinations thereof may be used to brace and/or anchor intelligent flow control valve  100  in a pipe. 
       FIG. 4  illustrates a bottom view of an exemplary embodiment of variable area control component  80  closed. When variable area control component  80  is closed, ring  75 , internal longeron frame  82 , expansion panels  84 , inner hinges  92 , outer hinges  94 , and slide points  86  are visible from the bottom of variable area control component  80 . 
       FIG. 5  illustrates a bottom view of an exemplary embodiment of variable area control component  80  fully deployed. When variable area control component  80  is fully deployed, expansion panels  84  are pushed out at both inner hinges  92  and outer hinges  94 , forming a cone shape (see  FIG. 7 ). 
       FIG. 6  illustrates a perspective view of an exemplary embodiment of variable area control component  80  closed showing inner hinges  92 , outer hinges  94 , and slide points  86  where expansion panels  84  are attached to internal longeron frame  82 . 
       FIG. 7  illustrates a perspective view of an exemplary embodiment of variable area control component  80  fully deployed. When umbrella control lead screw  15  (not shown) is rotated to deploy expansion panels  84 , fixed frame  70 , ring  75 , and internal longeron frame  82  slide downward along slide points  86 , pushing out expansion panels  84 . 
       FIG. 8  illustrates an exemplary embodiment of intelligent flow control valve  100  inside a pipe with variable area control component  80  in the closed position. 
     Intelligent flow control valve  100  is inserted into the open end of a flowing pipe with the variable area control component  80  inserted first. The shape of intelligent flow control valve  100  allows it be easily guided into the pipe. Frame  20  is expanded by rotating lead screw  10 , causing scissor action which pushes vertical arms  40  outward against the pipe walls, securing intelligent flow control valve inside the pipe. 
     Optional pyrotechnic anchoring components  50  (not shown) would then be fired to permanently anchor frame  20  and intelligent flow control valve  100 , if desired, to the pipe wall. 
     Once frame  20  is anchored, umbrella control lead screw  15  is rotated to activate variable area control component  80 . Rotating umbrella control lead screw  15  forces expansion of variable area control component  80  by sliding fixed frame  70 , ring  75 , and internal longeron frame  82  downward, pushing out inner folds  92  of expansion panels  84 . When variable area control component  80  is in its final position, expansion panels  84  rest against internal longeron frame  82 . In an exemplary embodiment, when variable area control component  80  is fully deployed, it blocks approximately 95% to 98% of the flow. 
     In various embodiments, additional components, such as rubber gaskets may be added around umbrella control lead screw  15 , ring  75 , and/or any other components where leaking may occur. 
     Intelligent flow control valve  100  substantially reduces the volume of fluid leaked while relief wells are implemented or the pipe is repaired. In addition, intelligent flow control valve  100  may be removed or umbrella control lead screw  15  may be turned in the reverse direction to increase flow at any time, allowing intelligent flow control valve  100  to remain in the pipe. 
     In various embodiments, intelligent flow control valve  100  may further include a pivot point between variable area control component  80  and frame  20  which allows intelligent flow control valve  100  to be inserted through curves in the pipe. In still other embodiments, variable area control component  80  may be decoupled from frame  20  before intelligent flow control valve  100  is inserted into the pipe. Variable area control component  80  is then attached to frame  20  when frame  20  has been secured in the desired location in the pipe. 
       FIG. 9  illustrates an exemplary embodiment of intelligent flow control valve  100  inside a pipe with frame  20  secured against the pipe walls and variable area control component  80  in the deployed position. 
       FIG. 10  illustrates an exemplary embodiment of variable area control component  80  used as a variable area flow meter. In the embodiment, variable area control component  80   a  is closed, covering approximately 20% of the pipe area; variable area control component  80   b  is partially deploying, covering approximately 50% of the pipe area; and variable area control component  80   c  is fully deployed, covering approximately 95% of the pipe area. 
     In the embodiment shown, pressure sensors  105  and differential pressure sensors  108  are placed before and after the variable area control components  80   a ,  80   b ,  80   c.    
       FIG. 11  illustrates an exemplary embodiment of intelligent flow control valve  100  for integrating with electronic flow calculation instrumentation which allows intelligent flow control valve  100  to be used as a differential head flow meter by adjusting the area of variable area control component  80  in response to different flowing conditions to enhance flow metering accuracy, control pressures losses, or control flows in a closed loop using feedback from the differential pressure across the device. In addition, using measured values from different flow areas enables estimation of fluid properties such as density and viscosity. 
     Visible in the embodiment shown are variable area control component  80  and lead screw  10 . In various other embodiments, variable area control component  80  may be actuated using other system, including, but not limited to hydraulic, pneumatic, flex muscle, etc.