Patent Publication Number: US-10760376-B2

Title: Pressure control valve for downhole treatment operations

Description:
BACKGROUND 
     Downhole systems rely on various valves to control fluid flow. On occasion, it is desirable to introduce a fluid, such as a chemical into a wellbore or other portion of a downhole system. Chemical injection systems typically rely on a normally closed chemical injection valve (CIV). The CIV includes a dart that is biased against a seat through a spring. A preload is applied to the spring prior to introducing the CIV downhole. A liquid is introduced into the CIV at a pressure sufficient to move the dart off the seat against the pressure applied by the spring. Once unseated, the liquid may then flow through the valve. 
     Once introduced downhole, the preload on the spring cannot be adjusted without withdrawing the CIV from the wellbore. Without modification of the preload, adjustments to liquid pressure are limited. That is, the liquid being introduced into the CIV must be at least at a pressure sufficient to unseat the dart. Withdrawing the CIV is a time consuming and costly process. Adjusting the preload is also a time consuming process requiring cutting the CIV open and then welding it closed. In most cases, if there are issues with the preload, the CIV is simply discarded. Accordingly, once a preload is chosen, operators are limited to a particular pressure floor for the liquid. 
     SUMMARY 
     A pressure control valve for downhole treatment operations includes a valve body including an inlet, an outlet, and a valve seat. A valve assembly is arranged in the valve body. The valve assembly includes a valve member selectively positionable on the valve seat to control fluid flow through the valve body. A piston assembly including a piston and a control fluid inlet is arranged in the valve body. The piston is operatively connected to the valve assembly. The piston is operable to bias the valve member toward a closed configuration upon exposure to a control fluid. 
     A resource exploration and recovery system includes a surface system including a fluid storage zone, and a downhole system including a plurality of tubulars and a pressure control valve. The pressure control valve includes a valve body including an inlet fluidically connected to the fluid storage zone, an outlet, and a valve seat. A valve assembly is arranged in the valve body. The valve assembly includes a valve member selectively positionable on the valve seat to control fluid flow through the valve body. A piston assembly including a piston and a control fluid inlet is arranged in the valve body. The piston is operatively connected to the valve assembly. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Referring now to the drawings wherein like elements are numbered alike in the several Figures: 
         FIG. 1  depicts a resource exploration and recovery system including a pressure control valve, in accordance with an exemplary embodiment; 
         FIG. 2  depicts a plan view of the pressure control valve, in accordance with an aspect of an exemplary embodiment; 
         FIG. 3  depicts a cross-sectional view of the pressure control valve of  FIG. 2  in a closed configuration; 
         FIG. 4  depicts a cross-sectional view of the pressure control valve of  FIG. 2  in an open configuration 
         FIG. 5  depicts a valve seat of the pressure control valve of  FIG. 3 ; 
         FIG. 6  depicts a plan view of a pressure control valve, in accordance with another aspect of an exemplary embodiment; 
         FIG. 7  depicts a cross-sectional view of the pressure control valve of  FIG. 6  shown in a closed configuration; 
         FIG. 8  depicts a cross-sectional view of the pressure control valve of  FIG. 6  shown in an open configuration; 
         FIG. 9  depicts a cross-sectional view of a setting tube of the pressure control valve of  FIG. 7 ; and 
         FIG. 10  depicts a valve fill adaptor for providing a change in control fluid in the pressure control valve of  FIG. 7  while downhole, in accordance with an aspect of an exemplary embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     A resource exploration system, in accordance with an exemplary embodiment, is indicated generally at  2 , in  FIG. 1 . Resource exploration system  2  should be understood to include well drilling operations, resource extraction and recovery, CO 2  sequestration, and the like. Resource exploration system  2  may include a surface system  4  operatively connected to a downhole system  6 . Surface system  4  may include pumps  8  that may aid in treatment, completion and/or extraction processes, as well as a fluid storage zone  10 . Fluid storage zone  10  may contain a gravel pack fluid or slurry (not shown), a fracturing fluid (also not shown), or a treating fluid that may be introduced into downhole system  6 . Surface system  4  may also include a control fluid source  12 . 
     Downhole system  6  may include a system of tubulars  20  that is extended into a wellbore  21  formed in formation  22 . One of tubulars  20  may support a pressure control valve  24  that may be employed to inject a fluid treatment into formation  22 . Pressure control valve  24  may be fluidically connected to fluid storage zone  10  through a first conduit  26 . Pressure control valve  24  may also be connected to control fluid source  12  through a second fluid conduit  28 . As shown in  FIGS. 2-5 , pressure control valve  24  includes a valve body  30  having an inlet  32  that may be fluidically connected to fluid storage zone  10  through first conduit  26  and an outlet  34 . Pressure control valve  24  includes a valve assembly  37  ( FIG. 3 ) arranged in a valve housing  39 . A piston assembly  41  is also arranged in valve housing  39  and operatively connected to valve assembly  37 . 
     Piston assembly  41  includes a piston  43  linked to a holder  45  that is selectively moveable along a support  46 . Piston assembly  41  includes a control fluid inlet  47  that may be fluidically connected to control fluid source  12 . Valve housing  39  may include an access cover  48  that provides access to valve assembly  37  and piston assembly  41 . A first fluid supply line connector  49  may be arranged at control fluid inlet  47 . First fluid supply line connector  49  connects to second fluid conduit  28  for delivering a control fluid to piston assembly  41 . A second fluid supply line connector  50  may be arranged at inlet  32 . Second fluid supply line connector  50  connects first conduit  26  to valve assembly  37  for delivering fluid, such as a treatment fluid, from fluid storage zone  10  through valve assembly  37 . 
     In accordance with an aspect of an exemplary embodiment, valve assembly  37  includes a setting tube  53  ( FIG. 3 ) operatively connected to piston  43  through holder  45 . Setting tube  53  includes a first end  56 , a second end  57 , and an intermediate portion  58 . Setting tube  53  is slideably arranged in a valve passage  60  defined by a wall  62 . Setting tube  53  is shown to include a flange  64  arranged at first end  56  and a recess  66  that is positioned on intermediate portion  58 . Recess  66  is receptive to holder  45 . Setting tube  53  also includes a passage  68  that extends through intermediate portion  58 . 
     In accordance with an aspect of an exemplary embodiment, valve assembly  37  includes a valve member  74  including a valve stem  78  and a valve  80 . Valve stem  78  that extends into passage  68  of setting tube  53 . Valve  80  interacts with a valve seat  83  ( FIG. 5 ) to selectively control fluid flow through valve assembly  37 . Valve  80  includes passage  84  and a number of sealing lands, two of which are indicated at  85  and  86  that interact with valve seat  83 . That is, over time, valve  80  may deform as a result of exposure to operating pressures. If valve  80  deforms, and valve seat  83  begins to fail, valve  80  may move deeper into valve seat  83  such that valve seat  83  may begin to seat thereby prolonging an overall operational life of valve assembly  37 . 
     Valve member  74  also includes a flange  90  having an outer surface  91  that arranged adjacent to wall  62  of valve passage  60 . In accordance with an aspect of an exemplary embodiment, a pressure chamber  93  may exist between flange  64  of setting tube  53  and flange  90  of valve member  70 . In accordance with an aspect of an exemplary embodiment, a passage  96  extends through valve stem  78  ( FIG. 5 ). Passage  96  includes an inlet portion  98  and a fluid outlet portion  99 . Inlet portion  98  may be fluidically connected to control fluid source  12 . In further accordance with an exemplary aspect, a cushioning spring  104  may be arranged between flange  64  of setting tube  53  and flange  90  of valve member  70 . Cushioning spring  104  attenuates any vibrations that may occur during operation of valve member  74 . 
     In accordance with an aspect of an exemplary embodiment, pressurized control fluid is introduced into piston assembly  41 . The control fluid pressure acts upon piston  43  moving setting tube  53  into valve passage  60 . Flange  64  urges against cushioning spring  104  which, in turn, urges against flange  90  guiding valve  80  onto valve seat  83  as shown in  FIG. 3 . A treating fluid may be introduced into setting tube  53  through inlet  32 . The treating fluid may pass through passage  96  in valve stem  78  and fluid into pressure chamber  93  through fluid outlet portion  99 . The treating fluid may act upon flange  90  causing valve member  70  to shift against the pressure applied through piston assembly  41  unseating valve  80  from valve seat  83  ( FIG. 4 ). At this point treating fluid may flow from inlet  32  through outlet  34  into, for example, formation  22 . 
     In accordance with an aspect of an exemplary embodiment, if it is desired to change treating fluid pressure, pressure control valve  24  provides operators with more flexibility in varying fluid pressure of the treating fluid. That is, if it is desirable to lower treating fluid pressure, adjustments may be made to also lower the control fluid pressure. In this manner a lower treating fluid pressure may be used to operate pressure control valve  24  without the need to withdraw tubulars  20  string from wellbore  21  to make adjustments. 
     Reference will now follow to  FIGS. 6-10  in describing a pressure control valve  110  in accordance with another aspect of an exemplary embodiment. Pressure control valve  110  includes a valve body  116  having a fluid inlet  118  that may be fluidically connected to fluid storage zone  10  through first conduit  26  and an outlet  120 . A valve assembly  124  ( FIG. 7 ) is arranged in a valve housing  128  of valve body  116 . A piston assembly  131  is also arranged in valve housing  128  and is operatively connected to valve assembly  124 . Piston assembly  131  includes a piston  134  operatively connected to a holder  136  that is shiftable along a support  138 . Piston assembly  131  also includes a control fluid inlet  140 . In a manner similar to that discussed above, valve body  116  includes an access cover  143  that provides access to valve assembly  124  and piston assembly  131 . 
     In accordance with an aspect of an exemplary embodiment, valve body  116  includes a control fluid reservoir  148  that is fluidically connected to control fluid inlet  140 . Control fluid reservoir  148  may contain an amount of pressurized control fluid that acts on piston  134  to bias pressure control valve  110  in a closed configuration such as shown in  FIG. 7  as will be detailed more fully below. Control fluid may be introduced to control fluid reservoir  148  through a selectively removable plug  150  fitted in valve housing  128 . 
     In accordance with an aspect of an exemplary embodiment, valve assembly  124  includes a setting tube  156  including a first end  158 , a second end  159 , and an intermediate portion  160  ( FIG. 9 ). Setting tube  156  is slideably arranged within a valve passage  162  defined by a wall  164 . First end  158  of setting tube  156  includes a flange  166  having an outer surface  167  that may transition along wall  164 . Setting tube  156  includes a recess  168  arranged along intermediate portion  160  that is receptive to holder  136 . In this manner, movements of piston  134  are imparted to setting tube  156  through holder  136 . 
     In accordance with an aspect of an exemplary embodiment, setting tube  156  includes a valve member  170  having a valve  171  extending axially outwardly from first end  158 . A passage  173  extends through setting member  153  to valve member  170  ( FIG. 9 ). Passage  173  includes an inlet portion  180  that may be fluidically connected with fluid inlet  118  through a valve conduit  181 , and a fluid outlet portion  182  arranged at flange  166 . Valve member  170  is selectively positionable on a valve seat  185  through movement of setting tube  156 . A pressure chamber  187  may exist between valve seat  185  and flange  166 . 
     In accordance with an aspect of an exemplary embodiment, control fluid pressure is introduced into piston assembly  131 . The control fluid pressure acts upon piston  134  moving setting tube  156  into valve passage  162  guiding valve  171  onto valve seat  185  as shown in  FIG. 7 . A treating fluid may be introduced into setting tube  156  through fluid inlet  118 . The treating fluid may pass through passage  173  via valve conduit  181  into setting tube  156  via fluid inlet  118 . The treating fluid may pass into pressure chamber  187  through fluid outlet portion  182 . The treating fluid may act upon flange  166  causing valve member  170  to shift against the pressure applied through piston assembly  131  unseating valve  171  from valve seat  185  ( FIG. 8 ). At this point treating fluid may flow from fluid inlet  118  through outlet  120  into, for example, formation  22 . 
     In accordance with an aspect of an exemplary embodiment, if it is desired to change treating fluid pressure, pressure control valve  110  provides operators with more flexibility in varying fluid pressure of the treating fluid. That is, if it is desirable to lower treating fluid pressure, adjustments may be made to also lower the control fluid pressure in control fluid reservoir  148 . For example, a tool (not shown) provided with a valve adaptor  190  ( FIG. 10 ) may be introduced downhole. The tool may be manipulated to release an amount of control fluid from control fluid reservoir  148 . In this manner a lower treating fluid pressure may be used to operate pressure control valve  110  without the need to withdraw tubulars  20  string from wellbore  21  to make adjustments. Additionally, if it is desirable to add additional control fluid or adjust control fluid pressure upwardly, the tool may be manipulated to add control fluid into control fluid reservoir  148  through valve adaptor  190 . Thus valve adaptor  190  provides operators with an ability to service pressure control valve  110  while deployed downhole. 
     Embodiment 1 
     A pressure control valve for downhole treatment operations comprising: a valve body including an inlet, an outlet, and a valve seat; a valve assembly arranged in the valve body, the valve assembly including a valve member selectively positionable on the valve seat to control fluid flow through the valve body; and a piston assembly including a piston and a control fluid inlet arranged in the valve body, the piston being operatively connected to the valve assembly, the piston being operable to bias the valve member toward a closed configuration upon exposure to a control fluid. 
     Embodiment 2 
     The pressure control valve according to embodiment 1, wherein the valve assembly includes a setting tube arranged in the valve body and operatively coupled to the piston, the setting tube including a first end, a second end, and an intermediate portion defining a conduit. 
     Embodiment 3 
     The pressure control valve according to embodiment 2, wherein the valve member includes a valve stem extending into the conduit of the setting tube. 
     Embodiment 4 
     The pressure control valve according to embodiment 3, wherein valve member includes a first flange arranged on the valve stem. 
     Embodiment 5 
     The pressure control valve according to embodiment 4, wherein the setting tube includes a second flange arranged at the first end. 
     Embodiment 6 
     The pressure control valve according to embodiment 5, further comprising: a cushioning spring arranged between the first flange and the second flange. 
     Embodiment 7 
     The pressure control valve according to embodiment 4, wherein the valve stem includes passage fluidically connected to the inlet. 
     Embodiment 8 
     The pressure control valve according to embodiment 7, wherein the valve member includes a fluid outlet portion fluidically connected to the passage. 
     Embodiment 9 
     The pressure control valve according to embodiment 1, further comprising: a control fluid source fluidically connected to the control fluid inlet of the piston assembly, the control fluid source introducing a pressurized control fluid into the piston assembly shifting the piston to bias the valve member in the closed configuration. 
     Embodiment 10 
     The pressure control valve according to embodiment 9, wherein the control fluid source comprises a fluid reservoir arranged in the valve body and fluidically connected to the control fluid inlet. 
     Embodiment 11 
     A resource exploration and recovery system comprising: a surface system including a fluid storage zone; and a downhole system including a plurality of tubulars and a pressure control valve comprising: a valve body including an inlet fluidically connected to the fluid storage zone, an outlet, and a valve seat; a valve assembly arranged in the valve body, the valve assembly including a valve member selectively positionable on the valve seat to control fluid flow through the valve body; and a piston assembly including a piston and a control fluid inlet arranged in the valve body, the piston being operatively connected to the valve assembly. 
     Embodiment 12 
     The resource exploration and recovery system according to embodiment 11, wherein the valve assembly includes a setting tube arranged in the valve body and operatively coupled to the piston, the setting tube including a first end, a second end, and an intermediate portion defining a conduit. 
     Embodiment 13 
     The resource exploration and recovery system according to embodiment 12, wherein the valve member includes a valve stem extending into the conduit of the setting tube. 
     Embodiment 14 
     The resource exploration and recovery system according to embodiment 13, wherein valve member includes a first flange arranged on the valve stem. 
     Embodiment 15 
     The resource exploration and recovery system according to embodiment 14, wherein the setting tube includes a second flange arranged at the first end. 
     Embodiment 16 
     The resource exploration and recovery system according to embodiment 15, further comprising: a cushioning spring arranged between the first flange and the second flange. 
     Embodiment 17 
     The resource exploration and recovery system according to embodiment 14, wherein the valve stem includes passage fluidically connected to the inlet, the passage including a fluid outlet portion. 
     Embodiment 18 
     The resource exploration and recovery system according to embodiment 11, further comprising: a control fluid source fluidically connected to the control fluid inlet of the piston assembly, the control fluid source introducing a pressurized control fluid into the piston assembly shifting the piston to bias the valve member in the closed configuration. 
     Embodiment 19 
     The resource exploration and recovery system according to embodiment 18, wherein the control fluid source comprises a fluid reservoir arranged in the valve body and fluidically connected to the control fluid inlet. 
     Embodiment 20 
     The resource exploration and recovery system according to embodiment 18, wherein the valve body includes a fluid supply line connector fluidically connected to the control fluid inlet, the control fluid source being arranged at the surface system and fluidically connected to the valve body through a fluid supply line fluidically connected to the fluid supply line connector. 
     The teachings of the present disclosure may be used in a variety of well operations. These operations may involve using one or more treatment agents to treat a formation, the fluids resident in a formation, a wellbore, and/or equipment in the wellbore, such as production tubing. The treatment agents may be in the form of liquids, gases, solids, semi-solids, and mixtures thereof. Illustrative treatment agents include, but are not limited to, fracturing fluids, acids, steam, water, brine, anti-corrosion agents, cement, permeability modifiers, drilling muds, emulsifiers, demulsifiers, tracers, flow improvers etc. Illustrative well operations include, but are not limited to, hydraulic fracturing, stimulation, tracer injection, cleaning, acidizing, steam injection, water flooding, cementing, etc. 
     While one or more embodiments have been shown and described, modifications and substitutions may be made thereto without departing from the spirit and scope of the invention. Accordingly, it is to be understood that the present invention has been described by way of illustrations and not limitation.