Patent Document

TECHNICAL FIELD 
       [0001]    The invention relates generally to oil and gas exploration and production and, more particularly, to a system and associated method for producing hydrocarbons from multiple layers of subterranean formations, and the mixing or comingling of such hydrocarbons as necessary or desired during the production process. The invention further relates to non-rotatable connections and environmentally contained systems of chambers and passages in subterranean tools. 
       BACKGROUND 
       [0002]    In a commonly encountered downhole scenario, it is desirable to have the capability to produce two different hydrocarbons or other varieties of production fluids from two different strata from a single submersible pump. To accomplish this, it is necessary to mix, or comingle the fluids. It may also be required to limit such comingling of the production zones. This may occur as a result of ownership rights or regulations or laws governing the production of such hydrocarbons and other regulations that further regulate the mixing or comingling of such fluids from multiple strata. 
         [0003]    Therefore, it may be desired to be able to regulate the flow rate of production fluids when simultaneously producing from two or more strata. As a result, various methods for regulating the flow of fluids down hole have been developed in the past, such as valves and chokes. However, such previous methods have been unable to effectively control the mixing or comingling of fluids from two strata to provide accurate, repeatable, and controlled mixing or have been unable to do so without expensive and cumbersome equipment prone to failure. 
         [0004]    For instance, a downhole valve may be configured while at the surface of the well to permit a certain flow rate for the comingling of two fluids down hole. The valve may then be installed into the wellbore for the regulation of fluid flow. However, as production commences, downhole conditions may subsequently change due to changes in reservoir pressure, temperature, fluid viscosity, etc. As a result, the downhole valve may need to be brought back to the surface for reconfiguration. Such necessary reconfiguration is expensive, tedious, and time consuming. As a result, each time the valve may need to be reconfigured will cause significant delays and expenses to the well operator. 
         [0005]    Alternatively, it has been conventional to utilize two separate sets of tubing in parallel in the wellbore to simultaneously produce hydrocarbons and other desired fluids from two or more different strata. The two sets of tubing in parallel may be connected to the two different desired strata and therefore two separate zones or reservoirs could be simultaneously produced with a single pumping mechanism. However, this method is cumbersome in that two separate tubings are necessary to run down the wellbore. In order to utilize two tubings simultaneously, the wellbore must be appropriately sized at a large enough diameter to accommodate both sets of tubing at the same time. This leads to additional costs during the drilling process. 
         [0006]    Conventional tools are not commercially practical due in a large part to the inability to effectively connect the power source to a electronic sensors and circuit boards housed in controlled pressure environments This is due to the need to construct tools in multiple sections and the long-standing convention connecting tubular sections together with threaded connections. The rotating connections prevents the creation of a continuous electronic passage, and in particular, the creation of a passageway and interconnected chambers for housing the sensitive electronic components in which the pressure of the passage and chambers is controlled contrary to the subterranean pressures experienced by the tool when in use. 
         [0007]    Thus, a significant challenge to providing such controls down hole is the extreme pressure and temperature near the bottom of the producing well, and the impact on these environmental conditions on computer processing electronics. 
         [0008]    Another significant challenge to providing such controls down hole is the need to connect electronics across sections of the tool that must be coupled together. This requirement prevents the use of threaded couplings, such as are the norm in drilling and production connections. 
         [0009]    Therefore, there is a need for a tool having the capability of providing surface controllable electronic controls for controlling the valve or choke to control the desired comingling of fluids from two different strata in an efficient and cost effective manner, and there is a further need for a downhole valve or choke that can be controlled by a well operator directly from the surface, without retrieving and reinserting the valve or choke. 
       SUMMARY 
       [0010]    The present invention addresses the deficiencies in the prior art by allowing better management of the process for producing hydrocarbons from multiple strata. One example is described herein through an exemplary embodiment of the present invention which allows a well operator to control a downhole choke or valve to regulate the flow of production fluid from a lower strata to an upper strata. Another example is described hereunder where the present invention may suitably determine the appropriate position of the valve through a plurality of downhole sensors. 
         [0011]    The bottom end of the tool is mounted to a hydraulic set packer located between an upper production zone and a lower production zone. The upper end of the tool is connected to the submersible pump. When the valve is closed, production will be limited to the upper zone. When the valve is opened, the lower zone fluid will enter the bottom of the tool and exit the valve on the side of the tool where it comingles with the upper zone fluid. In the present invention, the flow rate of the lower zone fluid is measurable and controllable. The comingling and production of two or more zones is accomplished in a smaller form factor than has been previously known. Rather, the present invention may produce hydrocarbons and other desired fluids from multiple downhole strata through the use of a single set of tubing, through the use of a motorized valve controlled by a downhole computer. 
         [0012]    The downhole computer in turn may be electronically connected to the surface of the well such that a well operator may preferably receive feedback on the downhole well conditions through a plurality of sensors located on the tool, as well as send appropriate control information to make further adjustments to the valve. Such feedback on the downhole conditions may include information on the current fluid flow rate, amount of water, downstream pressure, volume, rate of pressure change, etc. 
         [0013]    Thus, as the well production continues and encounters variously changing downhole conditions, the well operator may receive immediate updates on the current downhole conditions. The present invention further eliminates the need to retrieve the valve and adjacent downhole equipment, make the necessary adjustments, and return the valve to the wellbore before continuing production from a different strata in a multiple zone well. Furthermore, the present invention allows for the simultaneous production of multiple strata, thereby eliminating the necessity of sequential production of various strata, one at a time. 
         [0014]    These and other features, advantages, benefits and objects of the present invention will become apparent to one of ordinary skill in the art upon careful consideration of the detailed description of representative embodiments of the invention herein below and the accompanying drawings. 
         [0015]    The present invention provides a subterranean production tool, having a first section and a second section connectable at respective connecting ends. One of the first and second sections has a male flange at its connecting end with a substantially circular exterior. There is a first circumferential groove extending over at least a portion of the exterior. The other of the first and second sections has a female flange at its connecting end with a substantially circular interior. A second circumferential groove extends over a portion of the interior. A keyway is formed between the first and second grooves when the female flange is positioned over the male flange in aligned relationship. An access relief is located on an exterior surface of the female flange forming a passage to the keyway. A plurality of keys are provided for inserting through the access relief to enter into the keyway to prevent separation of the first section and the second section. 
         [0016]    In another embodiment, the first and second sections have a generally hollow tubular body with a cylindrical wall. A first electrical passage is located within the cylinder wall of the first section in lengthwise orientation. A second electrical passage is located within the cylinder wall of the second section in lengthwise orientation. The first and second passages are aligned to form a continuous passage between the first section and the second section. 
         [0017]    In another embodiment, the first and second passages are sealed so as to maintain an atmospheric pressure when the tool is operating in a subterranean environment. 
         [0018]    In another embodiment, an ungrooved portion remains on the interior of the female flange. In another embodiment, the keys have a curved interior surface and a curved exterior surface, with the interior and exterior surfaces being substantially parallel. The keys have opposing end surfaces that are unparallel with respect to each other. 
         [0019]    In another embodiment, the keyway holds between 8 and 11 keys. 
         [0020]    A fastener hole is provided on an exterior surface of the second section that passes through to the second groove. A key has a threaded center. A fastener is locatable in the fastener hole and connectable into the threaded center of the key to lock the key in position in the keyway. 
         [0021]    In another embodiment, a dowel pin is positioned axially between the first section and the second section. The dowel provides alignment between the first section and the second sections such that the first and second grooves form the keyway. The dowel prevents relative rotation between the first section and the second section when the male flange is positioned inside the female flange. 
         [0022]    In another embodiment, a threaded aperture extends through the female flange at a location non-intersecting with the second groove. A receiving groove circumscribes the exterior surface of the male flange. A fastener is connected to the threaded aperture such that it intersects the receiving groove. The fastener can be a set screw that biases the load between the first and second sections such that the keys support the tension load between the first and second sections. 
         [0023]    In another embodiment, the first and second sections are substantially hollow tubulars. In another embodiment, at least one of the first and second sections has a length at least 10 times an outer diameter of the respective section. 
         [0024]    In another embodiment, the first and second sections have a hollow tubular body with a cylindrical wall. A first electrical passage is located within the cylinder wall of the first section in lengthwise orientation A second electrical passage is located within the cylinder wall of the second section in lengthwise orientation. The first and second passages are aligned to form a continuous passage between the first section and the second section. The electrical passage passes through an ungrooved portion of the female flange. 
         [0025]    In another embodiment, a spool seal is provided at the juncture of the passages. In this manner, the connections between the first and second passages and the tool are sealed to maintain an atmospheric pressure within the electronic passages when the tool is operating in a subterranean environment. Electrical wiring inside the passage connects electrical components in the first section with electrical components in the second section. 
         [0026]    In another embodiment, the electrical passage passes through an ungrooved portion of the female flange. In another embodiment, the first section and the second section further comprise a circuit board having a processor, and an electric motor, electrically connected to the circuit board. A gearbox is connected to the motor, and a shaft extends from the gearbox. A rotatable valve is connected to the shaft. 
         [0027]    In another embodiment, a harmonic drive is connected to the gearbox to further reduce the speed of the shaft and increase the torque. In another embodiment, a pressure sensor is provided. An analog to digital converter is electrically connected to the sensor, and electrically connected to the circuit board. 
         [0028]    In another embodiment, a data wire is located inside the first and second passages. A condition monitoring instrument is located inside the second section, electrically connected to the data wire through the second portal. The condition monitoring instrument may be a resolver connected to the shaft. The resolver is electrically connected to the circuit board such that the position of the valve can be determined. 
         [0029]    In another embodiment, a tool having a hollow tubular body and having a cylindrical wall is provided. The body is comprised of a plurality of sections connected by non-threaded linear connections. An electrical passage is located within the cylinder wall of contiguous sections, located in lengthwise orientation. A seal is located in the electrical passage at a juncture between contiguous sections. Inside the tool sections is a circuit board having a computer processor; an electric motor electrically connected to the circuit board, a gearbox connected to the motor, and a shaft extending from the gearbox. 
         [0030]    The tool has an inlet orifice at one end for receiving a lower zone production fluid into the tool. An outlet port perforates the cylindrical wall of the tubular body. A rotatable valve is connected to the shaft, and has a vented portal. The valve is controllably rotatable between an open position, in which the vented portal is aligned with the outlet port and fluid inside the tool may flow through the outlet, and a closed position, in which the vented portal is not aligned with the outlet and flow through the outlet is blocked. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0031]    For a more complete understanding of the present invention, and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which: 
           [0032]      FIG. 1  is a cross-sectional view of a subterranean production tool embodying features of the present invention, and specially configured as a reservoir comingling tool. 
           [0033]      FIG. 2  is a cross-sectional side view of a top sub section of the comingling tool of  FIG. 1 . 
           [0034]      FIG. 3  is a cross-sectional end view of a non-threaded, non-rotatable key-slot coupling system of the present invention, as illustrated on the tool of  FIG. 1 , for non-rotated coupling of tool sections. 
           [0035]      FIG. 4  is an isometric view of a key, as used in the key-slot coupling system of  FIG. 3 . 
           [0036]      FIG. 5  is a cross-sectional side view of one embodiment of the key-slot coupling system of the present invention. 
           [0037]      FIGS. 6 and 7  are cross-sectional views of a computer section of the comingling tool of  FIG. 1 , with  FIG. 7  illustrating the tool rotated  90  degrees from the orientation illustrated in  FIG. 6 . 
           [0038]      FIGS. 8 and 9  are cross-sectional side views of a valve section of the comingling tool of  FIG. 1 , with  FIG. 9  illustrating the tool rotated  90  degrees from the orientation illustrated in  FIG. 8 . 
           [0039]      FIG. 10  is a cross-sectional side view of a sensor section of the comingling tool of  FIG. 1 . 
           [0040]      FIG. 11  is a cross-sectional side view of the coupling of the sensor section to the valve section of the tool, illustrating the sealed coupling of the electrical passageway. 
           [0041]      FIG. 12  is a side cross-sectional view of the Analog to Digital chamber of the sensor section of the tool. 
           [0042]      FIG. 13  is a side cross-sectional view of the casing sensor chamber of the sensor section of the tool. 
           [0043]      FIG. 14  is a side cross-sectional view of the tubing sensor chamber of the sensor section of the tool. 
       
    
    
     DETAILED DESCRIPTION 
       [0044]    The following description is presented to enable any person skilled in the art to make and use the invention, and is provided in the context of a particular application and its requirements. Various modifications to the disclosed embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the present invention. Thus, the present invention is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein. Additionally, as used herein, the term “substantially” is to be construed as a term of approximation. 
         [0045]      FIG. 1  is a cross-sectional view of a subterranean production tool  10  embodying features of the present invention, and specially configured as a reservoir comingling tool. Tool  10  may comprise several sections. In the embodiment illustrated, tool  10  comprises a top sub  100 , a computer section  200 , a valve assembly  300 , and a sensor assembly  400 . 
         [0046]    The names of the sections and assemblies are merely for convenience and not intended to completely describe, require, or limit the contents of any section of tool  10 , and as used here, do not. It is known that the beginnings and ends of the sections may be located to include or exclude certain equipment. It is also known that certain teachings of the present invention can be applied to other subterranean tools besides a comingler. 
         [0047]    Top sub  100  may be connected to computer section  200  by means of a non-threaded, and non-rotated connection  500 . Connection  500  may be described as a linear key-slot connection  500 . Such connections  500  are not known to have been used previously in the connection of tubulars for subterranean production. Computer section  200  is connected to valve assembly  300  by key-slot connection  500 . Similarly, valve assembly  300  is connected to sensor assembly  400  by key-slot connection  500 . 
         [0048]      FIG. 2  is a cross-sectional view of top sub  100  of tool  10  of  FIG. 1 . Top sub  100  comprises a tubular having a threaded pin connection  102  for connection to a production string component  20 , such as a submersible pump. Top sub  100  has a hollow center  104 . 
         [0049]    An electrical connector  230  is sealed in place inside hollow center  104  of top sub  100  by a bushing  232 . In this manner, electrical connections can be passed between the interior of computer section  200  and top sub  100  for connection to a power source, such as an electrical submersible pump, without passing environmental conditions and contaminants past bushing  232 . 
         [0050]    The lower end of top sub  100  has a male connector flange  110  having a circular exterior. A first groove  112  extends circumferentially over the circular exterior of male connector  110 . In an optional embodiment, first groove  112  does not extend over the full circumference of the exterior surface male connection  110 . 
         [0051]    Computer section  200  has a female connector  210  having a circular interior locatable over male connector  110  of top sub  100 . A second groove  212  extends circumferentially over a portion of the female connector interior. In the preferred embodiment, second groove  212  does not extend over the full circumference of the interior surface of female connector  210 . 
         [0052]    In the embodiment illustrated, top sub  100  includes one or more dowel holes  120  for receiving a portion of a dowel  570 . Computer section  200  includes one or more dowel holes  220  for receiving the opposite portion of dowel  570 . Dowel  570  serves to align top sub  100  with computer section  200  so that first groove  112  and second groove  212  are in matching alignment. In matching alignment, first groove  112  and second groove  212  form a keyway  516 . 
         [0053]      FIG. 3  is a cross-sectional view of a non-threaded, non-rotatable key-slot coupling system that is suitable for use with tool  10 . As best seen in this cross section, a male connector  510  has a circular exterior. A first groove  512  extends circumferentially over a portion or all of the circular exterior of male connector  510 . Optionally, first groove  512  does not extend over the full circumference of the exterior surface male connection  510 , and an ungrooved portion  514  remains. 
         [0054]    A female connector  520  has a circular interior, and is locatable over male connector  510 . A second groove  522  extends circumferentially over a portion of the interior of female connector  520 . Second groove  522  does not extend over the full circumference of the interior surface of female connector  520 . An ungrooved portion  524  is provided. An electrical passage  590  extends laterally through ungrooved portion  524  of female connector  520 . 
         [0055]      FIG. 4  is an isometric view of key  540 , as used in coupling assembly  500  of the present invention, and as illustrated in  FIG. 8 . As seen in  FIG. 4 , key  540  may have a threaded hole  542  through it. Key  540  has a curved outer surface  546  and a curved inner surface  544 . 
         [0056]    Key  540  has a curved inner surface  544  for sliding relationship with external groove  512  of male flange  510 . Key  540  has a curved outer surface  546  designed for sliding relationship with inner groove  522  of female flange  520 . Outer surface  546  and inner surface  544  are parallel. Key  540  has a pair of opposing end surfaces  548  and  550 . In the preferred embodiment, end surfaces  548  and  550  are not parallel. 
         [0057]    Referring to  FIG. 5 , complementary dowel slots  568  are provided in male connector  510  and female connector  520 . When male connector  510  is located inside female connector  520 , dowels  570  are located in slots  568  to provide alignment such that first groove  512  and second groove  522  align to form a keyway  516 . 
         [0058]    Referring back to  FIG. 3 , a first surface access relief  532  is provided on the surface of female connector  520  to provide passage to keyway  516 . A plurality of keys  540  is insertable through access relief  532  for sliding fit in keyway  516 . Optionally, a second surface access relief  534  is provided. Second access relief allows entry of a tool to push keys  540  out through first access relief  532 , and vice-versa, for disassembly of tool  10 . 
         [0059]    A fastener hole  528  is provided on female connector  520  for receiving a fastener  530 . One or more keys  540  has a threaded hole  542  for receiving fastener  530  in threaded engagement. Connection of fastener  530  to key  540  locks key  540  in position inside keyway  516 . In this manner, male connector  510  of a first section of tool  10 , and female connector  520  of a second section of tool  10  are locked in engagement, without the use of a conventional threaded connection. Dowels  570  resist relative rotation between male connector  510  of a first section of tool  10 , and female connector  520  of a second section of tool  10 . Keys  540  prevent lateral separation of male connector  510  of a first section of tool  10 , and female connector  520  of a second section of tool  10 . 
         [0060]    A second fastener hole  530  can also be provided on the opposite side of ungrooved portion  524 . Locating a second fastener hole  530  creates a stop for the remaining keys  540  to stack against. Alternatively, ungrooved portion  514  and/or ungrooved portion  524  may be used as an end-stop when inserting keys  540 . 
         [0061]      FIG. 5  is a cross-sectional side view of one embodiment of key-slot coupling system  500  illustrated in which a single male flange  510  is used to couple female flanges  520 A and  520 B of adjacent tubular sections of tool  10 . As illustrated, seals  562  are located in seal grooves  560  to create a sealed relationship between male flange  510  and female flanges  520 A and  520 B. Also as shown, a dowel  570  can be located in matching dowel holes  568  between female flanges  520 A and  520 B as well as between male flange  510  and female flange  520 . Receiving grooves  584  are shown on male flange  510  for receiving set screws  582  through threaded holes  580  (see example in  FIG. 9 ) in female flanges  520 A and  520 B. 
         [0062]      FIGS. 6 and 7  are cross-sectional views of computer section  200  of tool  10 . As seen in  FIG. 3 , computer section  200  is connected to valve assembly  300  by key-slot connection system  500 . In the embodiment illustrated, computer section  200  and valve assembly  300  are joined together over a gear insert  280 . Gear insert  280  provides the male connector for each key-slot connection  500  to which computer section  200  and valve assembly  300  are connected. 
         [0063]    As seen in  FIG. 6 , a threaded hole  580  is located through the female connector of computer section  200 . The male connector of gear insert  280  has a receiving groove  584  (see  FIG. 5 ) for receiving the tip of a set screw  582  located in threaded hole  580 . Another threaded hole  580  is located in the female connector of valve assembly  300  over the male connector of gear insert  280  for receiving a set screw  582  for engagement with a second receiving groove  584  on the male connector of gear insert  280 . Optionally, a drill point may be used in place of receiving groove  584 . 
         [0064]      FIG. 7  illustrates tool  10  rotated  90  degrees from the orientation illustrated in  FIG. 3 . Computer section  200  has a chamber  240  for housing a circuit board  242 . As used herein, circuit board  242  includes a computer or processor or other electrical system device for controlling tool  10 . 
         [0065]    Circuit board  242  is electrically connected to electrical connector  230  by electrical wiring (not shown). Bushing  232  seals electrical connector  230  to maintain an atmospheric pressure inside chamber  240  for the protection of circuit board  242 . An electrical passage  244  intersects the lower end of chamber  240 . A longitudinal electrical passage  250  also intersects chamber  240 . Electrical passage  250  is located near the outer diameter of tubular computer section  200  and runs substantially parallel to the centerline of computer section  200 . 
         [0066]    A motor  260  is located inside computer section  200 . Motor  260  is electrically connected to circuit board  242  through electrical passage  244 . An electrical connector  246  may be located between circuit board  242  and motor  260 . Electrical connector  246  may be sealed to computer section  200  to maintain the atmospheric (or near atmospheric) pressure condition inside chamber  240 . A gearbox  262  is connected to motor  260 . Gearbox  262  converts the speed of motor  260  into torque. A harmonic drive  264  may be connected to gear box  262  to further convert the speed of motor  260  into torque. 
         [0067]    An electrical passage  350  is located near the outer diameter of tubular valve section  300 . Electrical passage  350  is aligned with electrical passage  250  to form a continuous electrical passage for electrical connection of devices in valve section  300  with circuit board  242 . A spool seal  290  provides sealed connection of electrical passage  250  to electrical passage  350 . 
         [0068]      FIGS. 8 and 9  are cross-sectional side views of valve section  300  of tool  10 .  FIG. 9  illustrates tool  10  rotated 90 degrees from the orientation illustrated in  FIG. 8 . Referring to  FIG. 8 , a shaft  362  is connected to harmonic drive  264 . The opposite end of shaft  362  is connected to a rotatable valve  370 . Rotatable valve  370  has a vented opening  372 . Valve  370  rotates over a stationary valve body  380  that has a body opening  382 . Valve assembly  300  has an outlet port  306  connecting the exterior of tool  10  with the interior valve assembly  300  when valve  370  is open. Valve  370  is opened by aligning vented opening  372  between outlet port  306  and valve body opening  382 . 
         [0069]    A resolver  360  is positioned over shaft  362 . Resolver  360  is electrically connected to circuit board  242  through electrical passage  350  and electrical passage  250 . Resolver  360  is a condition monitoring device, used to determine the position of shaft  362  and thus the position of valve  370 . Resolver  360  communicates this information along data wires electrically connected to circuit board  242 . 
         [0070]    A computer or processor on circuit board  242  can be used to control the amount that valve  370  is opened as well as the opening and closing of valve  370 . Advantageous to the present invention is the ability to open valve  370  in any partially rotated amount. This gives tool  10  the ability to fully control the amount of fluid flow from the lower reservoir that is comingling with the production of the upper reservoir. 
         [0071]      FIG. 10  is a cross-sectional side view of sensor section  400  of tool  10 . Sensor section  400  is connected to valve section  300  by key-slot connection system  500 . An electrical passage  450  is located near the outer diameter of tubular sensor section  400 . Electrical passage  450  is aligned with electrical passage  350  to form a continuous electrical passage for electrical connection of devices in sensor section  400  with circuit board  242 . 
         [0072]      FIG. 11  is a cross-sectional side view of the connection between valve section  300  and sensor section  400 , illustrating the continuous sealed coupling of electrical passages  350  and  450 . In this embodiment, a spool bore  352  is provided at the end of each electrical passage  350  and  450 . A spool seal  390  is inserted in spool bores  352 . Spool seal  390  has a seal groove  394  on each end, and a spool o-ring  396  is located in each seal groove  394 . Spool o-rings  396  seal spool seal  390  to each of electrical passages  350  and  450  to provide a sealed connection of electrical passage  350  to electrical passage  450 . As a result, the environmental conditions inside electrical passage  450  are controlled to be the same as for chamber  240 . 
         [0073]      FIG. 12  is a side cross-sectional view of the analog to digital chamber of sensor section  400  of tool  10 . An analog to digital board  460  is located inside chamber  462 . Chamber  462  has a cover  464  that provides an environmentally protective enclosure for chamber  462 . An electrical passage  466  (see  FIG. 10 ) connects electrical passage  450  to sensor board chamber  462  located beneath cover  464 . 
         [0074]      FIG. 13  is a side cross-sectional view of a casing sensor chamber  472  of sensor section  400  of tool  10 . A casing sensor  470  is located inside sensor chamber  472 , in communication with annulus between the production casing and tool  10 . In this position, casing sensor  470  can measure environmental conditions such as pressure of the production zone flow outside of tool  10 . Chamber  472  has a cover  474  that provides an environmentally protective enclosure of chamber  472 . An electrical passage  476  connects chamber  470  with chamber  462  to provide a path for electrical connection of casing sensor  470  with analog to digital board  460 . 
         [0075]      FIG. 14  is a side cross-sectional view of a tubing sensor chamber  442  of sensor section  400  of tool  10 . A tubing sensor  440  is located inside sensor chamber  442 , in communication with annulus between the production tubing and tool  10 . In this position, tubing sensor  440  can measure environmental conditions such as pressure of the production zone flow inside tool  10 . Chamber  442  has a cover  444  that provides an environmentally protective enclosure of chamber  442 . An electrical passage  446  connects chamber  440  with chamber  462  to provide a path for electrical connection of tubing sensor  440  with analog to digital board  460 . 
         [0076]    As described herein above, the unique and novel features of tool  10  provide the beneficial ability to electronically connect electronic devices located in separate tool sections with a continuous electrical connector without the use of exposed plug connectors. Further, the unique and novel features of tool  10  provide the beneficial ability of maintaining an atmospheric pressure condition within tool  10  across several tool section connections  500 , where external conditions down hole include extreme pressures. 
       Operation 
       [0077]    References to section names, such as “upper” and “lower” or “computer,” “valve,” or “sensor,” are merely for convenience and not intended to completely describe, require, or limit the contents of any section of tool  10 , and as used here, do not. It is known that the beginnings and ends of the sections may be variously located to include or exclude certain equipment. It is also known that certain teachings of the present invention can be applied to other subterranean tools besides a comingler. 
         [0078]    Unique to the present inventions, among other aspects, is the non-threaded, and non-rotated coupling of contiguous sections  200 ,  300  and  400 . Connection system  500  may be described as a linear key-slot connection. Such connections  500  are not known to have been used previously in the connection of tubulars for subterranean production. Computer section  200  is connected to valve assembly  300  by key-slot connection  500 . Similarly, valve assembly  300  is connected to sensor assembly  400  by key-slot connection  500 . 
         [0079]    As seen in  FIG. 2 , top sub  100  comprises a tubular having a threaded pin connection  102  for connection to a production string component  20 , such as a submersible pump. Top sub  100  has a hollow center  104 . The submersible pump has electrical power supplied to it. Power wiring from the submersible pump is connected to electrical connector  230  in top sub  100  to power tool  10 . Electrical connector  230  is sealed in place inside hollow center  104  of top sub  100  by a bushing  232 . 
         [0080]    Bushing  232  seals chamber  240  in computer section  200  from the environmental pressure on the other side of bushing  232 . Key-slot connection  500  is fully detailed above, and only selected features are further detailed here. As described above, contiguous sections of tool  10  can be combined with a male flange  510  and a female flange  520 . They can also be combined as in  FIG. 5 , with abutting female flanges  520 A and  520 B over an internal male flange  510 . 
         [0081]    Dowels  570  serve to align the internal grooves  512  and external grooves  522  to form keyways  516 . Dowels  570  sections also serve to prevent relative rotation between the connecting sections of tool  10 . 
         [0082]    As seen in  FIG. 3 , keys  540  must slip into access relief  532 . Excessively large or excessively small keys  540  are undesirable, as they become difficult and time consuming to assemble, and lack body strength to accept fastener  530 , or support the tensile loads between the sections of tool  10 . To strike a balance between access and function, the preferred number of keys is between about 8 and 11, although a few more or less can be conveniently used. 
         [0083]    Set screws  582  are located in threaded holes  580  and intersect receiving grooves  584  to axially bias the load between the connecting sections of tool  10  (such as computer section  200  and gear insert  280 ) such that keys  540  support the primary tensile load between the connecting sections of tool  10 . 
         [0084]    As illustrated in  FIG. 5 , seals  562  can be located in seal grooves  560  to create a sealed relationship between male flange  510  and female flanges  520 A and  520 B. Dowels  570 , set screws  582  intersecting receiving grooves  584 , and seals  562  can be combined with the system of keys  540  in keyways  516  to form a more durable, linear, non-rotated, key-slot connection system  500 . It will be understood by a person of ordinary skill in the art that individual components of this system can be modified or substituted without departing from the teaching, suggestion, spirit, and scope of the invention. For example, receiving grooves may be replaced with drill points, or simply not included. 
         [0085]    A fundamental advantage of the use of key-slot connection  500  is that it enables tool  10  to incorporate a system of environmentally controlled electronic passages ( 250 ,  350 ,  450 ) and chambers ( 240 ,  442 ,  462 ,  472 ) connected by secondary passages ( 446 ,  466 ,  476 ). By use of key-slot connection  500 , the interconnected chamber and passage system (collectively “ 600 ”) can be created as between multiple sections (e.g.,  200 ,  300 ,  400 ). In particular, it is both unconventional and challenging to provide small diameter electronic passages such as  250 ,  350 , and  450  in the cylinder wall portion of a tubular body section of a subterranean tool. Referring  FIG. 3 , electrical passage  590  extends laterally through ungrooved portion  524  of female connector  520  of key-slot connection  500 . 
         [0086]    As seen in  FIG. 11 , a seal, such as spool seal  390  is inserted in spool bores  352 . Spool seal  390  provides a sealed connection between the electrical passages (e.g.,  250  and  350 ;  350  and  450 ) in contiguous sections  200 ,  300  and  400 . As a result, the environmental conditions inside interconnected chamber and passage system  600  is protected. 
         [0087]    Referring to  FIG. 7 , circuit board  242  receives electrical power through electrical connector  230  in top sub  100  ( FIG. 2 ). The submersible pump is the source of the electrical power. Circuit board  242  can send and receive data to the surface, through wiring connected to electrical connection  230 . Electrical connection  230  may be four wire connections and may include a fifth wire for ground. Additional connections may be provided. As stated above. circuit board  242  includes a computer or processor as necessary to operate tool  10 . 
         [0088]    Circuit board  242  provides power through wiring in secondary passage  244  to connector  246  which is sealed to the body of computer section  200  to maintain the environmental integrity of chamber and passage system  600 . Electrical connector  246  provides the connection for power to motor  260  for rotating valve  370 . 
         [0089]    Gearbox  262  converts the speed of motor  260  into torque. A harmonic drive  264  may be connected to gearbox  262  to further convert the speed of motor  260  into torque, transmitted through shaft  362  to operate valve  370 . Resolver  360  is electrically connected to circuit board  242  through electrical passage  350  and electrical passage  250 . Resolver  360  determines the position of shaft  362  and thus the position of valve  370 , and communicates this information to circuit board  242 . 
         [0090]    The lower end of tool  10  is connected to a packer set between the upper and lower producing zones. Tool  10  has an inlet orifice  402  near the lower end of tool  10 , for receiving a fluid from the lower producing zone into the inside  404  of sensor section  400 . Tubular sensor  440  obtains pressure and temperature data from the lower zone fluid inside tool  10 , and transmits the data to analog to digital board  460 . Casing sensor  470  obtains pressure and temperature data from the production fluid outside tool  10 , and transmits the data to analog to digital board  460 . Analog to digital board  460  converts the analog readings from the sensors and transmits the data to circuit board  242 , which transmits the information to the surface. 
         [0091]    An outlet port  306  extends through the cylindrical wall of sensor section  400 , adjacent to valve  370 . Valve  370  has a vented portal  372 . By instructions from the surface to circuit board  242 , valve  370  is controllably rotatable between an open position in which vented portal  372  is aligned with the outlet port  306  so that lower zone fluid inside tool  10  may flow through outlet port  306 . Lower zone fluid flowing through outlet port  306  is thus comingled with the upper zone fluid and pumped together by the submersible pump. 
         [0092]    When valve  370  is rotated to a closed position, vented portal  372  is not aligned with outlet port  306 , and the flow of lower zone production fluid through outlet port  306  is blocked by valve  370 . In the preferred embodiment, valve  370  valve is positionable to select any desired degree of alignment between the vented portal  372  with outlet port  306  to selectively control the rate of flow of lower zone fluid to be comingled with the upper zone fluid. 
         [0093]    A computer or processor on circuit board  242  can be used to control the amount of opening and closing of valve  370 , based on instructions from the surface, or based on a preprogrammed algorithm that responds to data from sensors  440 ,  470 , or other input. Advantageous to the present invention is the ability to open valve  370  in any partially rotated amount. This provides tool  10  with the desirable ability to fully control the amount of fluid flow from the lower reservoir that is comingling with the production of the upper reservoir. 
         [0094]    As described herein above, the unique and novel features of tool  10  provide the beneficial ability to electronically connect electronic devices located in separate tool sections with a continuous electrical connector without the use of exposed plug connectors. Further, the unique and novel features of tool  10  provide the beneficial ability of maintaining an atmospheric pressure condition within tool  10  across several tool section connections  500 , where external conditions downhole include extreme pressures. 
         [0095]    Having thus described the exemplary embodiments, it is noted that the embodiments disclosed are illustrative rather than limiting in nature and that a wide range of variations, modifications, changes, and substitutions are contemplated in the foregoing disclosure and, in some instances, some features of the present invention may be employed without a corresponding use of the other features. Many such variations and modifications may be considered desirable by those skilled in the art based upon a review of the foregoing description of preferred embodiments. Accordingly, it is contemplated that the appended claims will cover any such modifications or embodiments that fall within the true scope of the invention.

Technology Category: e