Abstract:
A valve for use in a flow management system comprising a valve including a body, a shuttle, and a seat closure, a rotatable shaft passing through the body and the seat closure, the rotatable shaft for operating a mechanical pump, and, translation of the seat closure along the rotatable shaft operable to mate the seat closure with a seat of the shuttle.

Description:
PRIORITY CLAIM &amp; INCORPORATION BY REFERENCE 
     This application is 1) a divisional of U.S. patent application Ser. No. 13/089,312 filed Apr. 19, 2011 and entitled VALVE WITH SHUTTLE which is 2) a continuation-in-part of U.S. patent application Ser. No. 12/766,141 filed Apr. 23, 2010 and entitled VALVE WITH SHUTTLE FOR USE IN A FLOW MANAGEMENT SYSTEM, now U.S. Pat. No. 8,545,190. These U.S. patent application Ser. Nos. 13/089,312 and 12/766,141 are incorporated herein, in their entireties and for all purposes. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a system for managing a fluid flow. In particular, the system includes a valve with a shuttle for managing a fluid flow. 
     2. Discussion of the Related Art 
     Pumps and valves located in hard to reach places present maintenance and maintenance downtime issues. Where pumps and valves are used to produce a natural resource such as a hydrocarbon, downtime can result in lost production and increased expenses for workmen and materials. 
     In particular, downhole production strings including pumps and valves for lifting fluids such as particulate laden liquids and slurries present a maintenance problem. Here, both pumps and valves can lose capacity and in cases be rendered inoperative when conditions including fluid conditions and fluid velocities fall outside an intended operating range. Such unintended operating conditions can foul, plug, and damage equipment. 
     Despite the industry&#39;s resistance to change, there remains a need to improve production strings. 
     SUMMARY OF THE INVENTION 
     The present invention includes a valve with a shuttle and is intended for use in a flow management system. 
     In an embodiment, a valve body includes a spill port and a shuttle is located in a chamber of the valve body. The shuttle has a through hole extending between a shuttle closure end and a shuttle spring end. A first seat and a first seat closure are located in the through hole. Second and third seats are located in the valve body chamber and second and third seat closures are located on the shuttle closure end. A spring is located substantially between the shuttle spring end and a fixture coupled to the valve body. The valve is operable to pass a flow entering the through hole at the shuttle spring end and to spill a flow that closes the first seat closure. In some embodiments, the circumference of the second seat is greater than the circumference of the third seat and the circumference of the shuttle spring end is more than two times greater than the circumference of the third seat. 
     In an embodiment, a valve body includes a spill port and a shuttle located in a chamber of the valve body. The shuttle has a through hole extending between a shuttle closure end and a shuttle spring end. A valve center line is shared by the valve body and the shuttle. A first seat is located on a first face of the shuttle and there is a first seat closure. The first seat closure has a central bore for accepting a rotatable shaft extending through the valve body and the first seat closure is for translating along the rotatable shaft. A second seat is located in the valve body chamber and a second seat closure is located on a second face of the shuttle. A spring is located substantially between the shuttle spring end and a valve body support. The valve is operable to pass a flow entering the through hole at the shuttle spring end and to spill a flow that closes the first seat closure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention is described with reference to the accompanying figures. These figures, incorporated herein and forming part of the specification, illustrate the invention and, together with the description, further serve to explain its principles enabling a person skilled in the relevant art to make and use the invention. 
         FIG. 1  is a schematic diagram of a valve in a flow management system in accordance with the present invention. 
         FIG. 2  is a diagram of the flow management system of  FIG. 1 . 
         FIG. 3  is a cross-sectional view of a valve of the flow management system of  FIG. 1 . 
         FIG. 4  is a cross-sectional view of a second valve of the flow management system of  FIG. 1 . 
         FIG. 5  is a cross-sectional view of a seal of the flow management system of  FIG. 1 . 
         FIG. 6  is a schematic diagram of a pump-off controller implemented in a traditional production string  600 . 
         FIG. 7  is a schematic diagram of a valve of  FIG. 1  used to implement a pump-off controller. 
         FIG. 8  is a flow chart showing a mode of operation of the valve of  FIG. 7 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The disclosure provided in the following pages describes examples of some embodiments of the invention. The designs, figures, and description are non-limiting examples of certain embodiments of the invention. For example, other embodiments of the disclosed device may or may not include the features described herein. Moreover, disclosed advantages and benefits may apply to only certain embodiments of the invention and should not be used to limit the disclosed invention. 
     To the extent parts, components and functions of the described invention exchange fluids, the associated interconnections and couplings may be direct or indirect unless explicitly described as being limited to one or the other. Notably, indirectly connected parts, components and functions may have interposed devices and/or functions known to persons of ordinary skill in the art. 
       FIG. 1  shows an embodiment of the invention  100  in the form of a schematic diagram. A bypass valve  108  is interconnected with a pump  104  via a pump outlet  106 . The pump includes a pump inlet  102  and the valve includes a valve outlet  110  and a valve spill port  112 . In various embodiments, the inlets, outlets and ports are one or more of a fitting, flange, pipe, or similar fluid conveyance. 
       FIG. 2  shows a section of a typical downhole production string  200 . The production string includes the bypass valve  108  interposed between the pump  104  and an upper tubing string  204 . In some embodiments, a casing  208  surrounds one or more of the tubing string, valve, and pump. Here, an annulus  206  is formed between the tubing string and the casing. A production flow is indicated by an arrow  102  while a backflow is indicated by an arrow  202 . In various embodiments, the bypass valve serves to isolate backflows from one or more of the valve, portions of the valve, and the pump. 
       FIG. 3  shows a first bypass valve  300 . A valve body  324  houses components including a valve shuttle  337  and a charge spring  312 . The valve body has a central chamber  323 . 
     The shuttle  337  includes an upper section  340  adjacent to a lower section  341 . In an embodiment, the central chamber includes a first bore  344  for receiving the lower shuttle section and a second bore  346  for receiving the upper shuttle section. In embodiments where the first and second bore diameters are different, a grease space  332  may be provided between the shuttle  337  and the valve body section  370  (as shown). In other embodiments, the first and second bore diameters are substantially the same and there is no grease space. 
     Upper and lower seals  314 ,  330  are fitted circumferentially to the upper shuttle section and the lower shuttle section  340 ,  341 . In an embodiment, the seals have a curved cross-section such as a circular cross-section (as shown). In another embodiment the seals have a rectangular cross-section. 
     In some embodiments, one or more seals  314 ,  330  have a structure  500  similar to that shown in  FIG. 5 . Here, a seal body  502  such as a polymeric body has inner and outer lip seals  506 ,  504  and substantially envelops a charge O-ring  508  such as a silicon rubber ring. 
     In various embodiments, the seals  314 ,  330  are made from one or more of a rubber, plastic, metal, or another suitable material known to persons of ordinary skill in the art. For example, seal materials include silicone rubber, elastomers, thermoplastic elastomers, and metals that are soft in comparison to the valve body  324 , the selection depending, inter alia, on the valve application. In an embodiment, the seals are made from ultra-high-molecular-weight polyethylene. 
     The shuttle has a through-hole  356  including an upper through-hole section  342  and a lower through-hole section  352 . Upper and lower through-hole ports  362 ,  360  bound a flow path through the shuttle indicated by the through-hole. In an embodiment, the upper through-hole cross-section is smaller than the lower through-hole cross-section. 
     Located near the lower through-hole section are a first seat closure  354 , a first seat  326 , and a seat retainer  393 . In an embodiment, the first seat is about radially oriented with respect to the valve body centerline  301 . 
     In an embodiment, the first seat closure  354  is a plug. In various embodiments, the first seat closure is spherically shaped, conically shaped, elliptically shaped, or shaped in another manner known to persons of ordinary skill in the art. And, in an embodiment, the first seat closure is substantially spherically shaped. The closure is movable with respect to the shuttle  337  within a cage  328 . When resting against the first seat  326 , the first closure seals the lower through-hole port  360 . In an embodiment, a stabilizer near an upper end of the cage  351  prevents the closure from blocking the passage comprising the upper and lower through-hole sections  342 ,  352  when the closure is near the upper end of the cage  390 . 
     Located near an upper valve body section  350  is a second seat  318 . In an embodiment, the second seat is about radially oriented with respect to the valve body centerline  301 . 
     A second seat closure  317  is located at an upper end of the shuttle  337 . In an embodiment, the second seat closure is located on a peripheral, sloped face of the shuttle  319 . In various embodiments, the second seat closure is spherically shaped, conically shaped, elliptically shaped, or shaped in another suitable manner known to persons of ordinary skill in the art. And, in an embodiment, the second seat closure is substantially frustoconically shaped. The closure is movable with the shuttle along a line substantially parallel to a centerline of the valve body  301 . 
     Located near the upper valve body section  350  is a third seat  368 . In an embodiment, the third seat is about radially oriented with respect to the valve body centerline  301 . About radially arranged and located between the second and third seats  318 ,  368 , are one or more spill ports  316  extending between a valve body exterior  372  and the valve body central chamber  323 . 
     A third seat closure  367  is located at a shuttle  337  upper end. In an embodiment, the third seat closure is located on a peripheral, sloped face of the shuttle  319 . In various embodiments, the third seat closure is spherically shaped, conically shaped, elliptically shaped, or shaped in another manner known to persons of ordinary skill in the art. And, in an embodiment, the second seat closure is substantially frustoconically shaped. The closure is moveable with the shuttle along a line substantially parallel to a centerline of the valve body  301 . 
     The second and third seat closures  317 ,  367  are formed to substantially simultaneously close the second and third seats  318 ,  368 . When resting against the second and third seats  318 ,  368 , the second closure establishes a flow path between a variable volume valve chamber below the shuttle  362  and an upper valve chamber above the second seat  364  while the third closure blocks flow in the spill port  316 . When moved away from the second seat, the second closure unblocks flow in the spill port. 
     Tending to bias the shuttle  337  upward is the charge spring  312 . In various embodiments, the charge spring is about radially oriented with respect to the valve body centerline  301  and is seated  384  on an annular fixture supported by the valve body  386 . In various embodiments, an upper end of the spring  382  presses against the shuttle. 
     In normal operation, forces on the shuttle determine the position of the shuttle. 
     An equilibrium position of the shuttle  337  in the valve body  324  is determined by the forces acting on the shuttle. 
     For example, when the pump  104  is lifting fluid through the valve  300 , the spring constant k of the charge spring  312 , the area A 1 , and the area A 2  are selected to cause a net upward force on the shuttle tending to move the shuttle to its uppermost position, sealing the spill ports  316 . At the same time, the rising fluid lifts the first closure away from its seat. These actions establish a flow path through the shuttle. In an embodiment, A 1  is greater than A 2 . And, in an embodiment, A 1  is about three times larger than A 2 . 
     When fluid lifting stops or falls below a threshold value, the net force on the shuttle tends to move the shuttle away from its uppermost position. At the same time, insufficient rising fluid causes the first closure  354  to come to rest against the first seat  326 . These actions unblock the spill ports  316  and establish a fluid flow path from the upper chamber  364  to the spill port(s)  316  while blocking the flow path through the shuttle. In some embodiments, the threshold value is a flow rate specified by the pump manufacturer as being a recommended or safe pump flow rate. 
     From the above, it can be seen insufficient fluid flow, no fluid flow, or reverse fluid flow cause the valve  300  and pump  104  to be substantially removed from the fluid circuit and/or isolated from the fluid column above the shuttle  337 . A benefit of this isolation is protection of the valve and pump. One protection afforded is protection from solids (such as sand), normally rising with the fluid but now moving toward the valve and pump, that might otherwise foul or block one or both of these components. Blocking the shuttle flow path and opening the spill ports  316  removes these solids outside the tubing string  204 . 
     In various embodiments the valve  300  is made from metals or alloys of metals including one or more of steel, iron, brass, aluminum, stainless steel, and suitable valve seat and closure materials known to persons of ordinary skill in the art. And, in various embodiments, one or more parts of the valve are made from non-metals. For example, valve closures and seats may be made from one or more suitable polymers such as PTFE (Polytetrafluoroethylene), POM (Polyoxymethylene) and PEEK (Polyetheretherketone). In an embodiment, the closure  354  is made from materials including PEEK. 
       FIG. 4  shows a second bypass valve  400 . A valve body  424  houses components including a valve shuttle  437 , a valve closure  483 , and a charge spring  412 . The valve body has a central chamber  423  and a rotatable shaft  482  passes through the central chamber. The shuttle includes an upper section  440  adjacent to a lower section  441 . 
     Upper and lower seals  414 ,  430  are fitted circumferentially to the upper shuttle section and the lower shuttle section  440 ,  441 . In one embodiment, the seals have a curved cross-section such as a circular cross-section. In another embodiment, the seals have a rectangular cross-section (as shown). 
     In some embodiments, one or more seals  414 ,  430  have a structure  500  similar to that shown in  FIG. 5 . Here, a seal body  502  such as a polymeric body has inner and outer lip seals  506 ,  504  and substantially envelops a charge O-ring  508  such as a silicon rubber ring. 
     And, in various embodiments, the seals  414 ,  430  are made from one or more of a rubber, plastic, metal, or another suitable material known to persons of ordinary skill in the art. For example, seal materials include silicone rubber, elastomers, thermoplastic elastomers, and metals that are soft in comparison to the valve body  424 , the selection depending, inter alia, on the valve application. In an embodiment, the seals are made from ultra-high-molecular-weight polyethylene. 
     The shuttle and valve closure  437 ,  483  have through-holes  456 ,  457  and the rotatable shaft  482  passes through these through-holes. In various embodiments, no “in/out” tools are required to insert the rotatable shaft through the shuttle and valve closure as their hole dimensions pass shafts with diameters as large as the drift of the tubing through which they pass. A first face of the shuttle in the form of a first seat  468  is for sealing against a face of the valve closure  467 . In an embodiment, the first seat is near an upper end of the shuttle  440  and the valve closure sealing face is near a lower end of the valve closure  488 . In some embodiments, the first valve seat is about radially oriented with respect to the valve body centerline  401 . In various embodiments, the shuttle sealing face is integral with or coupled to the shuttle. And, in various embodiments, the valve closure sealing face is integral with or coupled to the valve closure. 
     A second face of the shuttle  417  is for sealing against a face of the valve body in the form of a second seat  418 . In an embodiment, the second seat is near an upper section of the valve body  450  and the second face of the shuttle is near an upper end of the shuttle  440 . In some embodiments, the second valve seat is about radially oriented with respect to the valve body centerline  401 . In various embodiments, the shuttle sealing face is integral with or coupled to the shuttle. And, in various embodiments, the second seat is integral with or coupled to the valve body  424 . 
     About radially arranged and located between upper and mid valve body sections  450 ,  470  are one or more spill ports  416 . Each spill port extends between inner and outer walls of the valve body  471 ,  472 . 
     Tending to bias the shuttle  437  upward is the charge spring  412 . In various embodiments, the charge spring is about radially oriented with respect to the valve body centerline  401  and is seated  413  in a slot  496  formed in a valve body center section  470 . In an embodiment, an upper end of the spring  415  presses against the shuttle. 
     During normal operation of a flow management system using the second bypass valve  400 , the shaft  482  rotates and operates the pump  104 . Forces on the shuttle  437  and valve closure  483  determine their position. When the pump  104  is lifting fluid within the tubing and within a designed flow-rate range  490 , the shuttle is in its uppermost position  494  under the influence of the charging spring  412  and the rising fluid lifts the valve closure free of the shuttle  484 . Notably, in its uppermost position, the shuttle blocks the spill ports  416  when shuttle sealing face  417  seals with the first seat  418 . In some embodiments designed flow-rate ranges are the flow-rates specified by the pump manufacturer as recommended and/or safe pump operating ranges. 
     When the pump  104  ceases to lift fluid at a sufficient rate, as with back-flow  491 , the valve closure contacts the shuttle  486  and the valve closure sealing face  467  seals with the second seat  468 . Further, if pressure P 11 ,P 22  induced forces cause the shuttle to compress the spring  412 , the shuttle moves downward and the spill port(s)  416  is unblocked allowing fluid in the tubing above the valve to spill outside the valve  400 , for example into the annular space between the tubing and the casing  206 . In various embodiments, pressure P 11  acts on an annular area defined by radii r 1  and r 4  while pressure P 22  acts on an annular area defined by r 1  and r 3 . Here, the annular areas are different such as in a ratio range of about 1.5-2.5 to 1 and in an embodiment in a ratio of about 2.0 to 1. In various embodiments, the spill port(s) is unblocked when the shuttle forces resulting from the pressure above the first seat P 22  and the shuttle mass overcome the force of the charging spring  412  and the force resulting from the pressure below the valve closure P 11 . 
     When the pump  104  ceases to lift fluid at a sufficient rate, as with back-flow  491 , the valve closure contacts the shuttle  486  and the valve closure sealing face  467  seals with the second seat  468 . Further, if pressure P 11 ,P 22  induced forces cause the shuttle to compress the spring  412 , the shuttle moves downward and the spill port(s)  416  is unblocked allowing fluid in the tubing above the valve to spill outside the valve  400 , for example into the annular space between the tubing and the casing  206 . In various embodiments, pressure P 11  acts on an annular area defined by radii r 1  and r 4  while pressure P 22  acts on an annular area defined by r 1  and r 3 . Here, the annular areas are different such as in a ratio range of about 1.5-2.5 to 1 and in an embodiment in a ratio of about 2.0 to 1. In various embodiments, the spill port(s) is unblocked when the shuttle forces resulting from the pressure above the first seat P 22  and the shuttle mass overcome the force of the charging spring  412  and the force resulting from the pressure below the valve closure P 11 . 
     From the above, it can be seen insufficient fluid flow, no fluid flow, or reverse fluid flow cause the valve  400  and pump  104  to be removed from the fluid circuit and/or isolated from a fluid column above the shuttle. A benefit of this isolation is protection of the valve and pump. One protection afforded is protection from solids (such as sand), normally rising with the fluid but now moving toward the valve and pump, that might otherwise foul or block one or both of these components. Blocking the flow path around the shuttle and opening the spill port(s)  416  removes these solids outside the tubing string  204 . 
     In various embodiments the valve  400  is made from metals or alloys of metals including one or more of steel, iron, brass, aluminum, stainless steel, and suitable valve seat and closure materials known to persons of ordinary skill in the art. And, in various embodiments, one or more parts of the valve are made from non-metals. For example, valve closures and seats may be made from one or more suitable polymers such as PTFE (Polytetrafluoroethylene), POM (Polyoxymethylene) and PEEK (Polyetheretherketone). In an embodiment, the closure  483  is made from materials including PEEK. 
     In various embodiments incorporating one or more of the features described above, the bypass valves of  FIGS. 3 and 4  provide fouling/plugging protection to valves and fouling/plugging/burn-out protection to pumps due to contaminants such as sand. For example, below design production flow rates causing abnormal valve/pump operation or damage in traditional production string equipment is avoided in many cases using embodiments of the bypass valves of the present invention. 
     Notably, embodiments of the bypass valves of  FIGS. 3 and 4  can replace or supplement protection systems now associated with some production strings. One such protection system is the “pump-off controller” (“POC”) used to protect pumps from failures due to abnormal operations such as reduced flow conditions and loss of flow conditions. 
       FIG. 6  shows an illustrative example of a pump off controller installation in a production string  600 . The portion of the production string  612  illustrated includes a pump  602  lifting product from a reservoir  614  to the surface  616 . A pump-off controller  608  receives power from a power source  607  and provides power to the pump  610  in accordance with a control algorithm. For example, a pressure indicating device  604  monitors a pressure near the pump discharge  611  and provides a signal indicative of pressure  606  to the pump-off controller. If the pump-off controller determines the indicated pressure is below a preselected low-pressure set point, the POC stops supplying power to the pump. Conditions causing low pump discharge pressure include insufficient product at the pump inlet  613  (i.e. a “dry suction”), pump fouling, and pump damage. Attempting to run the pump under any of these conditions has the potential to damage or further damage the pump. 
       FIG. 7  shows a pump-off controller embodiment of the present invention  700 . A production string  701  includes a flow management system with a pump  736  interposed between a reservoir  738  and a valve  734 . Product the pump lifts from the reservoir  729  passes first through the pump and then through a bypass valve  734 . The bypass valve discharges  721  into a tubing space  704  of a tubing string  702  that is surrounded by a casing  712  creating an annulus  714  between the outer casing and the inner tubing. 
       FIG. 8  shows a mode of bypass valve operation that substitutes for or augments a production string pump-off controller  800 . For example, after a period of normal operation  802 , the pressure differential (P 111 &gt;P 222 ) driving the flow in a production string  721  begins to fall  804 . As explained above, low flow conditions cause the closure  354 ,  483  to mate with the shuttle  337 ,  437  which blocks flow through the valve along its centerline  301 ,  401 . When the forces on the shuttle  337 ,  437  are no longer sufficient to maintain the shuttle in a position to block the spill port  316 ,  416 , the shuttle moves to unblock the spill port/open the bypass  806 . During bypass operation  808 , flow through the valve is blocked and the spill port(s) is open, product flows from the upper tubing string  723 , enters the upper valve chamber  364 ,  464 , and leaves the valve through its spill port(s)  725 . The spill port empties into a space such as an annulus between the tubing and the casing  614 . 
     Because the annulus  614  is fluidly coupled to the reservoir  738  (e.g. as shown in  FIG. 7 ), valve bypass from the spill ports is returned to the reservoir  727  in the replenishment step  810 . In various embodiments, filling the reservoir with the fluid from the valve bypass serves to flood the suction of the pump, lift the closure  354 ,  483 , and unblock the flow through the valve along its centerline  301 ,  401  where normal flow is re-established in step  812 . Re-establishment of normal flow is followed by a return to normal operation in step  814 . 
     The pump-off control steps of  FIG. 8  result, in various embodiments, in cyclic flows through the pump. The time between these cyclic flows is shorter than would occur with a traditional valve in a traditional production string configuration because such strings are unable to bypass flow to the reservoir. 
     As persons of ordinary skill in the art will appreciate, many production string pumps rely on the pumped product as pump lubrication and coolant. Therefore, reducing the duration of dry pumping periods reduces pump damage due to operation with insufficient lubricant and coolant. The benefits include one or more of longer pump life, fewer outages, and higher production from tight reservoirs. 
     The present invention has been disclosed in the form of exemplary embodiments; however, it should not be limited to these embodiments. Rather, the present invention should be limited only by the claims which follow where the terms of the claims are given the meaning a person of ordinary skill in the art would find them to have.