Abstract:
The present invention provides a family of devices insertable into a pipe or pipeline for counteracting the force and controlling the rate of flow of a fluid flowing in the pipe or pipeline. The disclosed devices have an overall shape resembling a spear to improve the fluid dynamic performance and are designed to be self-centering in a pipe. The devices can be made from readily available materials using well known manufacturing techniques. Other embodiments showing extensions to the invention are also disclosed.

Description:
RELATED PATENT APPLICATIONS 
       [0001]    This application claims priority to U.S. provisional patent application Ser. No. 61/458,005, filed Nov. 16, 2010, which is hereby incorporated by reference in its entirety. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to counteracting the force of fluid flow in a pipe or pipeline and more particularly, to the controlling and potentially stopping the flow of fluid in said pipeline. 
       BACKGROUND OF THE INVENTION 
       [0003]    Counteracting the force and rate of fluid flow in pipes or pipelines has many potential applications including but not limited to water, air, natural gas and various forms of oil. Force is an action that changes or tends to change the state of motion of the body upon which it acts. Controlling the rate of flow can sometimes be relatively easy to implement if the control mechanism was properly built into the application and included appropriate redundancy and safety means. But for various reasons including cost, ignorance and greed, a reliable system to counteract the force and rate of fluid flow in a pipe or pipeline and even stop it if necessary has not always been implemented or implemented properly. Implementing a reliable system can be made more difficult for some applications due to the location or working environment. A good example of this is the recent oil spill from the British 
         [0004]    Petroleum (BP) Deepwater Horizon (BPDH) drilling rig and associated well in the Gulf of Mexico, a disaster of massive proportion that very likely will affect the environment for decades to come. It took over 100 days to allegedly “kill” the well and to stop the leaking of oil and gas from the array of devices and pipes of varying diameters that make up the well. 
         [0005]    The term “pipeline” as used herein is intended to describe a plurality of segments of pipe that may vary in diameter along the length of the pipeline. For example in deepwater oil and gas drilling, it is common practice that the lower pipe segments are of a smaller diameter, (e.g., 7 inches in diameter) than the ones closest to the surface (e.g., 21 inches in diameter). While the pressure of the fluid flowing through both the smaller and larger diameter pipe segments is the same, the force of the fluid in the larger diameter pipe is equal to the pressure times the square of the radius of the pipe. Therefore the force of the fluid in the 21-inch diameter pipe is 9 times greater than in the 7-inch diameter pipe even though the diameter is only three times greater. This is one reason that the 2010 British Petroleum (BP) Deepwater disaster has been so difficult to contain/control due to the high forces of the fluid at the top of the well. 
         [0006]    There have been myriad of possible solutions proposed to stop the flow of oil and gas with limited success. Furthermore there are thousands of additional wells that already may or could potentially be leaking gas and oil and need to be dealt with before another ecological disaster occurs. 
         [0007]    While it is most desirable to have wells and pipelines implemented with a reliable system to control the flow of fluid in the associated pipes, it would be highly desirable to have a scalable family of devices that can be applied to existing applications as well as new applications that require fluid control. 
         [0008]    It would be desirable to insert a device into a smaller diameter pipe, if at all possible in order to reduce the rate of flow of fluid in a pipeline while the fluid is flowing. This may be difficult to accomplish because the device would have to pass through the larger diameter pipes, being subjected to the resistance of the high forces before it could reach the smaller diameter pipe. Therefore it would also be desirable for a device to have an overall shape that would minimize resistance thus optimizing, or at least greatly improving the fluid dynamics of the device to make it easier to install the device in the desired location. 
         [0009]    It is therefore an object of the invention to enhance the art of controlling the flow of fluid in a pipe or pipeline. 
         [0010]    It is another object of the invention to provide a scalable family of devices to effectively stop or reduce the flow of fluid in a pipe or pipeline even in existing applications where fluid is already flowing. 
         [0011]    It is another object of the invention for the family of devices to have an overall shape that would minimize resistance thus optimizing or at least greatly improving the fluid dynamics of the device to make it easier to install the device in the desired location. 
       SUMMARY OF THE INVENTION 
       [0012]    The present invention provides a family of devices insertable into a pipe or pipeline for altering the rate of flow of the fluid flowing in the pipeline. The disclosed devices have an overall shape resembling a spear to improve the fluid dynamic performance and are designed to be self-centering in a pipe. In a preferred embodiment the device comprises a plurality of prolate spheroid shaped members that help to reduce and, if desired, stop the flow of fluid in the pipe since the spheroids help to counteract the force of the fluid flowing in the pipe. The devices can be made from readily available materials using well known manufacturing techniques. Other embodiments showing extensions to the invention are also disclosed. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    A complete understanding of the present invention may be obtained by reference to the accompanying drawings, when taken in conjunction with the detailed description thereof and in which: 
           [0014]      FIG. 1  is a perspective view of a device to control the rate of flow of fluid in a pipe in accordance with a first embodiment of the present invention shown in  FIGS. 1-7 ; 
           [0015]      FIG. 2  is a side view of one of the components of the device shown in  FIG. 1 ; 
           [0016]      FIG. 3  is a top view of another of the components of the device shown in  FIG. 1 ; 
           [0017]      FIG. 4  is a top view of another of the components of the device shown in  FIG. 1 ; 
           [0018]      FIG. 5  is an exploded view of yet more components of the device shown in  FIG. 1  emphasizing the relative position of the cam dogs in an open position and prepared for engagement; 
           [0019]      FIG. 6  is an exploded view of the components shown in  FIG. 5  emphasizing the relative position of the cam dogs in a closed position after engagement to the inner surface of a pipe; and 
           [0020]      FIG. 7  is a cross sectional view of the device shown in  FIG. 1  emphasizing the relative positioning of the device when inserted into a pipe and near the boundary between pipes of two different diameters. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0021]    Generally speaking, the present invention provides a family of devices insertable into a pipe or pipeline for counteracting the force of the fluid flowing in the pipeline. 
         [0022]    Referring first to  FIG. 1 , there is shown a perspective view of a device  10  to control the rate of flow of fluid in a pipe  30  (see  FIGS. 6 and 7 ) in accordance with a first embodiment of the present invention. Device  10  (see  FIGS. 1-7 ) comprises components including a center sweep  12 , guide fins  14   a - 14   d,  and a plurality of cam dogs  18 , dowels  20 , pins  22 , and springs  24 . Device  10  has an overall shape resembling a spear to improve its fluid dynamic performance, is about ten feet in length, and weighs about  860  pounds. Device  10  is designed to be self-centering in a pipe. The tip  10   a  of device  10  will strive to find the point of least resistance in the fluid flowing against it. Therefore tip  10   a  will try to locate the center of the fluid flow in pipes  30  and  32  (see  FIG. 7 ). It is desirable for device  10  to be long and “sharp” which allows device  10  to penetrate through pipes  30  and  32  further with less opposing resistance although too long a length can be a problem in certain applications described hereinbelow. It is also preferable that the materials used to make device  10  are capable of withstanding the application specific environmental conditions. 
         [0023]    Testing of scale models of device  10  has shown that device  10  not only worked well (i.e., to reduce the rate of flow of fluid in a pipeline while the fluid is flowing), but an unexpected benefit was observed: as device  10  moves through pipe  30 , and as the largest diameter portion of the largest diameter plug ( 12   e  in this embodiment) of device  10  moves very close to the inner wall of pipe  30 , instead of the device  10  experiencing more resistance, instead it fortuitously is “sucked” or pulled further into pipe  30  due to the Bernoulli effect (i.e., the Bernoulli principle or Bernoulli&#39;s law), which improves the performance of device  10 . 
         [0024]    In this embodiment center sweep  12  (see  FIGS. 1 ,  2  and  7 ) comprises five football-shaped plugs  12   a - 12   e  connected to one another by rods  12   fa - 12   fe . Plugs  12   a - 12   e  and rods  12   fa - 12   fe  are preferably made of a very strong material such as steel. Plugs  12   a - 12   e  are also similar in shape to a prolate spheroid. Center sweep  12  in this embodiment is axially concentric with respect to a major axis of device  10  and may be made by various processes including but not limited to as a single poured metal part, as a single machined part, or as an assembly of the various components. Rods  12   fa - 12   fe  and plugs  12   a - 12   e  may even be separable from one another if, for example, they were threaded. This capability would allow one or more of the components to be detachable. 
         [0025]    The graduated increase in size of plugs  12   a - 12   e  in center sweep  12  is preferred over a continuously variable shape because it allows device  10  the inherent ability to counteract the dynamic force of the fluid in pipe  30  by allowing the flow and pressure of the fluid to slowly decrease in a sequential manner as device  10  is pushed further into pipe  30 , thereby reducing the insertion force. Plugs  12   a - 12   e  preferably have a smooth exterior to minimize friction thereby increasing the rate of propulsion of device  10 . 
         [0026]    Referring in particular to  FIG. 7 , it is important to note that if the maximum diameter of plug  12   e  is only incrementally larger than the diameter of pipe  30  that it is being inserted into, there may be the possibility of damaging pipe  30  due to the high forces potentially created against the interior surface of pipe  30  and therefore this condition should be avoided. One solution is to make the maximum diameter of plug  12   e  large enough to literally “seal” pipe  30  with cam dogs  18  holding device  10  within pipe  30 . This is, of course, assuming the goal is the total closure of the pipe to seal off the fluid flow and pressure. In this embodiment plug  12   e  includes an additional design feature, a stop  28 , which is implemented as a larger diameter step that cannot fit into pipe  30  and catches on end of pipe  30  rather than on an inner surface. Therefore it is preferable that the maximum diameter of stop  28  is larger than the inside diameter of pipe  30  but no larger than the inside diameter of pipe  32 . Stop  28  ensures that while the majority of device  10  will fit within a section of pipe  30  to be plugged, the entire device  10  cannot become a wedge that is potentially capable of splitting pipe  30 . Stop  28  would also work similarly even if pipe  32  was not present. 
         [0027]    The “seal” can be implemented in many ways such as but not limited to stop  28  disclosed hereinabove; an o-ring; an inflatable bladder; a resilient, compressive layer on plug  12   e;  or a combination thereof. Once closure of pipe  30  is accomplished, a material such as concrete or other appropriate material(s) could be injected into pipe  30  and  32  or well head to provide an additional level of sealing. Device  10  may be inserted into pipe  30  in various ways including mechanically-assisted means, and gravity-based means such as railroad rails stacked on end, or a “coupled pipe” filled with concrete. Device  10  could even be “fired” into pipe  30  by an appropriate apparatus. 
         [0028]    It should be obvious to one skilled in the art that characteristics such as the quantity, individual shape, dimensions, materials, and interconnection of plugs  12   a - 12   e  may vary depending on the particular application. For example, although in this embodiment plugs  12   a - 12   e  are in increasingly larger size, there may be certain applications where it may be desirable if one or more of plugs  12   a - 12   e  might differ in size, shape, quantity or material from the overall sequentially increasing shape as shown in device  10 . 
         [0029]    There may be applications where pipelines are curved at such a rate that the approximately ten foot long device  10  may not be able to be properly inserted into. This problem may be solved in several ways. One way is to divide device  10  in a series of two or more shorter “sub-devices” that can be individually inserted in increasing sequentially larger size. Another solution is to have plugs  12   a - 12   e  interconnected by means functionally similar to a ball joint or the way a universal joint is used to connect a drive shaft and a drive axle in an automobile. Then device  10  would be able to navigate around turns with a much tighter radius. A third solution is to make rods  12   fa - 12   fe  from an equally strong but more flexible material. Other solutions to accomplish this same goal should be understood by those skilled in the art. 
         [0030]    Device  10  comprises four guide fins  14   a - 14   d  (see  FIGS. 1 ,  3  and  4 ) that are preferably made of a material such as steel, mounted  90  degrees apart from one another and are attached to device  10  along the length of each guide fin  14   a - 14   d  by a process such as welding. Guide fins  14   a - 14   d  are disposed parallel to the major axis of device  10 . In this embodiment at least one pair of fins  14   a  with  14   c,  or  14   b  with  14   d  are made as a pair to simplify construction (see  FIG. 3 ). Each guide fin  14   a - 14   d  includes a plurality of openings  16  on the edge outermost from the center of device  10 . It should be understood that other materials, quantities, configurations, orientations and attachment processes may be used for fins  14   a - 14   d  to accomplish the same or similar functionality, and that modifications may be required to improve device  10  performance for certain applications without departing from the spirit of the invention. 
         [0031]    Guide fins  14   a - 14   d  (see  FIG. 7 ) preferably have a smooth outer surface to minimize turbulence, and are intended to help device  10  to be self centering once inserted pipe  30  and/or  32 , and also to minimize the chances of device  10  inadvertently getting prematurely lodged or “caught” on pipe  30  and/or  32  prior to being inserted far enough to accomplish the desired goal(s). 
         [0032]    A plurality of spring activated cam dogs  18  are attached to at least one of guide fins  14   a - 14   d.  Cam dogs  18  act as a one way clutch, similar to a ratchet, to allow device  10  to enter pipe  30  ( FIGS. 6 and 7 ) and to lock and lodge to the interior surface of the inner pipe wall while prohibiting device  10  from being ejected by the pressure of the fluid. Each cam dog  18  is retained to one of fins  14   a - 14   d  by a corresponding dowel  20 , which allows cam dog  18  to rotate around dowel  20 . Dowel  20  may be retained in many different ways. The disclosed approach is for dowel  20  to be press fit into guide fin  14   a - 14   d.  If dowel  20  had a nail-like head on one end, it could be held in place by a single retaining ring. Another variant of dowel  20  also could be held on each side of guide fin  14   a - 14   d  by retaining rings. 
         [0033]    The movement of cam dog  18  is constrained at both ends of travel. When device  10  is in an initial “open cam dog” position (see  FIG. 5 ), the position of cam dog  18  is limited by coming in contact with a corresponding pin  22  in one of guide fins  14   a - 14   d.  In this default position, cam dogs  18  extend outward by the force provided by springs  24 . Springs  24  are preferably of a die spring type used primarily in die machinery since they are also well-suited for many applications where high-static or shock-load stresses are required, or when maximum cycle-life is important. In this embodiment rectangular wire is employed to reduce the solid height and increase the space efficiency of the design. It should be understood that other types and materials of springs  24  may also be used. 
         [0034]    Once open cam dogs  18  begin to come in contact with the inner surface of pipe  30 , gripping edge  26 , especially at the two outer edges, starts to push against and eventually “dig” or “bite” into the inner surface of pipe  30  forcing spring  24  to compress and cam dog  18  to rotate on dowel  20  and to start retracting into opening  16 , whose shape and dimensions limits the extent of travel of cam dog  18  and provides a stop at the other extreme and therefore determines the minimum outer diameter of device  10  when device  10  is in a “closed cam dog” position (see  FIGS. 6 and 7 ). Once the force between corners of gripping edge  26  of cam dog  18  and pipe  30  become high enough as device  10  is attempted to be further inserted into pipe  30 , it will be very difficult for device  10  to be easily removed or dislodged from pipe  30 , unless the ability to release cam dogs  18  is included in a particular design. 
         [0035]    While device  10  was primarily designed to stop the flow of fluid as completely as possible, it should be readily apparent to those skilled in the art that by changing design characteristics such as the diameter of the largest plug  12   e  and the distance that cam dogs  18  allow between device  10  and the inner diameter of pipe  30  when device  10  is in a “closed cam dog” position, the rate of flow of a fluid can be controlled. 
         [0036]    Device  10  could be used to control the rate of flow of fluid in pipe  30  or  32  enough that another valve, for example, a ball valve could be fitted to the end of a properly prepared end of pipe  30  or  32  thereby allowing a more controlled and variable fluid flow. 
         [0037]    Various components of device  10  may benefit from having a coating to accomplish different goals or improve performance. For example coating various components such as a plug  12   e , even if it did not include stop  28 , with a resilient material may provide a superior seal between plug  12   e  and the interior wall of pipe  30  and even allow the possibility of the entire device  10  being inserted into pipe  30  with a much lower risk of damaging pipe  30 . 
         [0038]    The inclusion and design of the various components that comprise device  10  are intended to optimize the performance of device  10 . While adequate performance may be accomplished with an embodiment that potentially combines the functionality of some of the components (e.g., integrating some form of a fin into, or attaching cam dogs directly to modified plugs), even though the performance of such a device may not necessarily be up to the same level as a design that uses a “divide and conquer” approach to truly optimize the performance of each component and function of a given design, a more integrated type of device could still be useful and cost effective for certain applications and without departing from the spirit of the invention. 
         [0039]    Device  10  could be modified to be self-powered, sort of like a torpedo, controlled remotely, and incorporating sensors to monitor quantities such as pressure and flow rate at various positions such as the center and edges of a pipe. The remote control capability could be used to control and direct the positioning of device  10 , determine the positioning and actuation of cam dogs  18 , send and receive information from the sensors, as well as but not limited to other tasks. The remote capability may be implemented in several ways including permanent wiring, detachable wiring, and wireless communication. 
         [0040]    Device  10  could also be modified to incorporate interlocking elements that work in conjunction with mating elements that could be designed into or added onto pipe  30  and/or  32 , or a well bore, etc. to offer addition functionality and/or performance improvement. For example, one or more of cam dogs  18  or plugs  12   a - 12   e  could be designed and built with interlocking means such as but not limited to threads that would allow device  10  to interlock with mating threads or other design features on the inner surface of a pipe or a well bore. The specific implementation of such features is application dependent. 
         [0041]    Device  10  could further be modified to incorporate one or more of plugs  12   a - 12   e,  but preferably plug  12   e,  to be redesigned and built to include a valve (e.g., a ball valve) (not shown) internal to plug  12   e,  with the valve connected to a plurality of openings (not shown) on the portions of plug  12   e  located both below and above the “seal” (e.g., see stop  28  in  FIG. 7 ), thereby allowing device  10  the potential to again allow fluid to flow through pipes  30  and  32 , but now in a controlled manner and only if desired. The internal valve may be controlled directly, remotely, or even a combination thereof. Again, the specific implementation of this feature is application dependent. 
         [0042]    Since other modifications and changes varied to fit particular operating requirements and environments will be apparent to those skilled in the art, this invention is not considered limited to the representative examples chosen for purposes of this disclosure, and covers all changes and modifications which do not constitute departures from the true spirit and scope of this invention. 
         [0043]    Having thus described the invention, what is desired to be protected by Letters Patent is presented in the subsequently appended claims.