Patent Publication Number: US-9428993-B2

Title: System and method for controlling flow in a pipe using a finger valve

Description:
PRIORITY 
     This application is a continuation application of utility application Ser. No. 13/425,399 filed Mar. 20, 2012. 
    
    
     BACKGROUND 
     This disclosure relates to a system and method for controlling flow in a pipe string using a finger valve. 
     The demand for natural gas and oil has significantly grown over the years making low productivity oil and gas reservoirs economically feasible, where hydraulic fracturing plays an important part in these energy productions throughout the world. For several decades different technology has been used to enhance methods for producing resources from oil and gas wells. Long horizontal wellbores with multiple fractures is one commonly used process to enhance extraction of oil and gas from wells. This process starts after a well has been drilled and the completion has been installed in the wellbore. Multi-stage fracking is a method that involves pumping large amounts of pressurized water or gel, a proppant and/or other chemicals into the wellbore to create discrete multiple fractures into the reservoir along the wellbore. 
     One of the technologically advanced methods being used today is simultaneous proppant fracturing of up to thirty fractures in one pumping operation. This method involves usage of proppant to prevent fractures from closing. However, this practice can usually cause an uneven distribution of proppant between the fractures, which will reduce the efficiency of the fracture system. As a result, this practice can also cause fractures to propagate in areas that are out of the target reservoir. Thus, such method can be inefficient and unsafe. 
     Additionally, proppant fracturing usually involves multiple steps and requires several tools in order to be performed successfully. Such practice that will allow even distribution of proppant between fractures, highly depends on setting plugs between the fracture stages or using frack balls of increasing sizes. In these methods, plugs are either set after each fracture has been perforated and pumped, or frack balls are dropped from the surface to successively open fracturing valves placed along the well. For each stage, balls of different diameters are dropped into the well corresponding to a specific fracturing valve&#39;s seat. At a point in the well, the ball will no longer pass through due to a decrease in well diameter. Once the ball is in place, fracking can take place. After fracking, the plugs must be drilled out and the balls must be recovered. With each fracturing stage while setting plugs, much time and energy is expended in tripping out of the hole between the stages and drilling out the plugs. Moreover, land-based rigs are usually rented per day basis, and so any delays can be quite expensive. Also, only about 12 different fracture stages is possible with the ball method before a restriction in flow area due to small ball diameter makes fracturing difficult due to large pressure losses. 
     As such it would be useful to have a system and method for controlling flow in a pipe string using a finger valve. 
     SUMMARY 
     Described herein is a system and method for controlling flow in a pipe string using a finger valve. Specifically, the disclosure describes a finger valve comprising a base pipe and a sliding sleeve. The base pipe can comprise a finger port, one or more fingers; and one or more hinges, each of the hinges connecting one of the fingers to the base pipe. The sliding sleeve can comprise a sliding sleeve having a first sleeve with in inner surface comprising a void and a depressor. The first sleeve can be positionable in a first position and a second position. In the first position, the depressor can push the one or more fingers into a closed position. In the second position, the void can rest at least one of the one or more fingers, allowing the at least one of the one or more fingers to move into an open position. 
     The disclosure also describes a method for controlling flow in a pipe string using a finger valve, comprise the steps connecting a base pipe within a pipe string, and actuating a sliding sleeve from a first position to a second position. The base pipe can comprise a finger port, one or more fingers; and one or more hinges, each of the hinges connecting one of the fingers to the base pipe. The sliding sleeve can comprise a first sleeve having an in inner surface with a void and a depressor. In the first position, the depressor can push the one or more fingers into a closed position. In the second position, the void can rest at least one of the one or more fingers, allowing the at least one of the one or more fingers to move into an open position. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  illustrates a side view of a base pipe. 
         FIG. 1B  illustrates a front view of a base pipe. 
         FIG. 1C  illustrates a cross sectional view of a base pipe. 
         FIG. 1D  illustrates a cross sectional of a base pipe. 
         FIG. 2A  illustrates a sliding sleeve connected to a fixed sleeve by an actuator, and in line with an outer ring. 
         FIG. 2B  illustrates a front view of a sliding sleeve. 
         FIG. 2C  illustrates a cross sectional view of a sliding sleeve. 
         FIG. 2D  illustrates a cross sectional view of a sliding sleeve that further comprises a fixed sleeve, and an actuator. 
         FIG. 3A  illustrates a peripheral view of an outer ring. 
         FIG. 3B  illustrates a front view of an outer ring. 
         FIG. 4A  illustrates a valve casing. 
         FIG. 4B  illustrates a fracking port of a valve casing 
         FIG. 4C  illustrates a production slot of a valve casing. 
         FIG. 5  illustrates a finger valve in a closed mode. 
         FIG. 6  illustrates a finger valve in an open mode. 
     
    
    
     DETAILED DESCRIPTION 
     Described herein is a system and method for controlling flow in a pipe string using a finger valve. The following description is presented to enable any person skilled in the art to make and use the invention as claimed and is provided in the context of the particular examples discussed below, variations of which will be readily apparent to those skilled in the art. In the interest of clarity, not all features of an actual implementation are described in this specification. It will be appreciated that in the development of any such actual implementation (as in any development project), design decisions must be made to achieve the designers&#39; specific goals (e.g., compliance with system- and business-related constraints), and that these goals will vary from one implementation to another. It will also be appreciated that such development effort might be complex and time-consuming, but would nevertheless be a routine undertaking for those of ordinary skill in the field of the appropriate art having the benefit of this disclosure. Accordingly, the claims appended hereto are not intended to be limited by the disclosed embodiments, but are to be accorded their widest scope consistent with the principles and features disclosed herein. 
       FIG. 1A  illustrates a side view of a base pipe  100 . Base pipe  100  can be connected as a portion of a pipe string. In one embodiment, base pipe  100  can be cylindrical, and can comprise a finger  101  and a finger port  102 .  FIG. 1B  illustrates finger  101  connected Finger  101  can connect to base pipe  100  by a hinge  103 . In one embodiment, a first biasing device  104  can also connect base pipe  100  to finger  101 . In another embodiment, first biasing device  104  can operationally be a part of hinge  103 . Biasing device  104  can be a spring. By connecting first biasing device to finger  101  and base pipe  102 , finger can be biased to an open or closed position. For exemplary purposes, this disclosure illustrates finger  101  biased in an open position. In another embodiment, biasing device  104  can be a portion of finger  101  and/or base pipe  100  that has been magnetized to bias finger  101  into an open or closed position. In one embodiment, base pipe  100  can also comprise a first portion of fracking port  105  and/or a production port  106 . First portion of fracking port  105  can be made of one or more openings, and production port  106  can also be made of one or more openings in base pipe  100 . 
       FIG. 1C  illustrates a front view of base pipe  100 . Base pipe  100  can further comprise a chamber  107 . When fingers  101  are in an open position, chamber  107  can be an empty space or an opening that can allow materials to pass through. However, when fingers  101  are in a closed position, the fingers  101  come together to create a significant or complete blockage to chamber  107 , substantially or completely preventing materials from passing through base pipe  100 . 
       FIG. 1D  illustrates a cross sectional of a base pipe  100  further comprising base ring  108 . In one embodiment finger port  102  can be a plurality of orifices spaced radially around base pipe  100 . In another embodiment finger port  102  can be a cylindrical segment missing from base pipe  100 . First portion of fracking port  105  can be circularly placed around the middle part of base pipe  100 . Production port  106  can be circularly placed around the rear portion of base pipe  100 . 
       FIG. 2A  illustrates a sliding sleeve  200  connected to a fixed sleeve by an actuator  208 , and in line with an outer ring  209 . In one embodiment, sliding sleeve  200  can be a cylindrical material that can comprise a second portion of fracking port  105 . In one embodiment, sliding sleeve  200  can have an opening large enough to fit base pipe  100 .  FIG. 2B  illustrates a front view of a sliding sleeve  200 . Sliding sleeve  200  can further comprise a sleeve chamber  201 . Sleeve chamber  201  can be an opening large enough to house base pipe  100 . 
       FIG. 2C  illustrates a cross sectional view of a sliding sleeve  200 . Sliding sleeve  200  can comprise a first sleeve  202  and a second sleeve  203 . Further, first sleeve  202  and a second sleeve  203  can be attached through one or more curved sheet  204 , the spaces between each curved sheet  204  defining a portion of fracking port  105 . Inner surface of first sleeve  202  can comprise surface attributes that interact with one or more fingers  101 . Surface attributes can comprise a first attribute and a second attribute. First attribute can be one or more voids  205  and second attribute can be a depressor  206  capable of moving finger  101  to a closed position. Void  205  can extend radially around the complete inner diameter of base pipe  100 , partially around the inner diameter, or local to a single radial position. If completely around the inner diameter, the ends of inner surface can have a smaller diameter than the void. If local, void  205  can comprise a plurality of local depressions positioned radially around the inner surface of sliding sleeve  200 . 
       FIG. 2D  illustrates a cross sectional view of a sliding sleeve  200  further comprising fixed sleeve  207 , connected to fixed sleeve  207  by actuator  208 , and in line with outer ring  209 . In one embodiment, actuator  208  can be a biasing device such as a spring. Second sleeve  203  of sliding sleeve  200  can be attached to fixed sleeve  207  using actuator  208 . In one embodiment wherein actuator  208  is a biasing device, sliding sleeve  200  can be pulled towards fixed sleeve  207 , thus compressing or otherwise load biasing device  208  with potential energy. Later biasing device  208  can be released or otherwise instigated, pushing sliding sleeve  200  away from fixed sleeve  207 . In another embodiment, actuator  208  can retrieve sliding sleeve  200  to its original position. Fixed sleeve  207  is depicted in the above figures as a cylinder, but in practice may not be a continuous loop. Instead, fixed sleeve  207  may be any device or devices connected to base pipe  100  that gives actuator  208  a foothold to push connect to or push against to actuate sliding sleeve  200 . In one embodiment, fixed sleeve  207  can be a component of actuator  208 . 
       FIG. 3A  illustrates a peripheral view of outer ring  209 . In one embodiment outer ring  209  can be a solid cylindrical tube forming a ring chamber  301 , as seen in  FIG. 3B . In another embodiment, outer ring  209  can be attached to base ring  108  of base pipe  100 . In one embodiment outer ring  209  can be an enclosed solid material forming a cylindrical shape. A ring chamber  301  can be the space formed inside outer ring  209 . Ring chamber  301  is large enough to slide over base pipe  100 . Outer ring  300  can be fixed to base pipe  100 . In one embodiment, outer ring  209  can be used to halt forward progress of sliding sleeve  200  during actuation. 
       FIG. 4A  illustrates a valve casing  400 . In one embodiment, valve casing  400  can be a cylindrical material, which can comprise a third portion of fracking port  105 , and production port  106 . As such third portion of fracking port  105  can be a plurality of openings circularly placed around valve casing  400 , as seen in  FIG. 4B . Further, production port  106  can be one or more openings placed around valve casing  400 , as seen in  FIG. 4C . 
       FIG. 5  illustrates a finger valve  500  in a closed mode. In an embodiment wherein fracturing valve  500  can be used in fracturing a well, fracturing valve  500  can comprise base pipe  100 , sliding sleeve  200 , outer ring  300 , and/or valve casing  400 . In such embodiment, base pipe  100  can be an innermost layer of finger valve  500 . A middle layer around base pipe  100  can comprise outer ring  300  fixed to base pipe  100  and sliding sleeve  200 , wherein fixed sleeve  207  is fixed to base pipe  100 . Finger valve  500  can comprise valve casing  400  as an outer layer. Valve casing  400  can, in one embodiment, connect to base ring  108 , outer ring  209  and fixed sleeve  207 . In a fracking position, fracking port  105  can be aligned and open, due to the relative position of base pipe  100  and sliding sleeve  200 . 
     At an open state, biasing device  208  can be in a loaded state further moving the hinges and pushing finger  101  into chamber  107 . In such state, finger  101  can be in a closed form, blocking the path of fluid in chamber  107 . Finger valve  500  can be useful in fracturing a well, for example, as shown in  FIG. 5 , in a closed state fracking port  105  will be open, allowing flow of proppant from chamber  107  through fracking port  105  and into a formation, thereby allowing fracturing to take place. 
       FIG. 6  illustrates finger valve  500  in open mode. As sliding sleeve  200  is pushed towards outer ring  209  by biasing device  208 , finger  101  can be pushed to rise up. When used in well fracturing, sliding sleeve  200  can concurrently close fracking port  105  and open production port  106 , allowing materials to pass through base pipe  100 . Once production port  106  is opened, extraction of oil and gas can start. In one embodiment, a plurality of finger valves  500  can be put in a well. After one has been used to fracture a well, another can be used downstream. In such embodiment, each production port can have a check valve to allow fracking to continue downstream without pushing frack fluid through the production port. 
     Various changes in the details of the illustrated operational methods are possible without departing from the scope of the following claims. Some embodiments may combine the activities described herein as being separate steps. Similarly, one or more of the described steps may be omitted, depending upon the specific operational environment the method is being implemented in. It is to be understood that the above description is intended to be illustrative, and not restrictive. For example, the above-described embodiments may be used in combination with each other. Many other embodiments will be apparent to those of skill in the art upon reviewing the above description. The scope of the invention should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. In the appended claims, the terms “including” and “in which” are used as the plain-English equivalents of the respective terms “comprising” and “wherein.”