Patent Publication Number: US-8978753-B2

Title: Cyclonic strainer

Description:
REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to U.S. Provisional Application Ser. No. 61/240,476 titled CYCLONIC NIPPLE DEVICE FOR A WELL INTAKE which was filed on Sep. 8, 2009 by Michael Brent Ford and is hereby incorporated in its entirety. 
    
    
     TECHNICAL FIELD 
     The present application relates generally to fluid and gas well apparatuses and, more particularly, to a cyclonic strainer for a well intake that provides for improved separation of gas and fluid in naturally flowing wells during mechanical pumping operations. 
     BACKGROUND 
     In completed fluid and gas wells, the wellbore can be lined with piping known as tubing. The tubing can extend from the bottom of the wellbore and be opened to the earth&#39;s surface. In a naturally flowing well, formation pressure typically forces fluid and gas through the tubing, bringing it to the surface. The natural pressure in a completed well eventually diminishes, however, and when this occurs, pumping systems can be installed in the tubing to mechanically remove oil or other fluid from beneath the earth&#39;s surface. 
     An oil well pumping system begins with an above-ground pumping unit, which is commonly referred to as a “pumpjack,” “nodding donkey,” “horsehead pump,” “beam pump,” “sucker rod pump,” and the like. The pumping unit can create a reciprocating up and down pumping action that moves the oil or other substance being pumped out of the ground and into a flow line, from which the oil is then taken to a storage tank or other such structure. 
     A string of sucker rods is inserted into the tubing, which ultimately can be indirectly coupled at its north end to the above-ground pumping unit. The string of sucker rods can be coupled at its south end to a subsurface pump that is located at or near the fluid in the oil well. The subsurface pump has a number of basic components, including a barrel and a plunger. The plunger operates within the barrel, and the barrel, in turn, is positioned within the tubing. It is common for the barrel to include a standing valve and the plunger to include a traveling valve. The standing valve can have a ball therein for the purpose of regulating the passage of oil from down-hole into the pump, allowing the pumped matter to be moved northward out of the system and into the flow line, while preventing the pumped matter from dropping back southward into the hole. Oil can be permitted to pass through the standing valve and into the pump by the movement of the ball off its seat, and oil is prevented from dropping back into the hole by the seating of the ball. 
     South of the standing valve are a number of basic components, typically including such items as a seating nipple and a strainer or gas anchor, as well as other components. North of the standing valve, coupled to the sucker rods, can be the traveling valve. The traveling valve can regulate the passage of oil from within the pump northward in the direction of the flow line, while preventing the pumped oil from dropping back southward, in the direction of the standing valve and hole. 
     Oil can be pumped from a hole through a series of downstrokes and upstrokes of the pump when motion is imparted by the above-ground pumping unit. During the upstroke, formation pressure causes the ball in the standing valve to move upward, allowing the oil to pass through the standing valve and into the barrel of the oil pump. This oil can be held in place between the standing valve and the traveling valve. In the traveling valve, the ball can be located in the seated position, held there by the pressure from the oil that has been previously pumped. 
     On the downstroke, the ball in the traveling valve unseats, permitting the oil that has passed through the standing valve to pass therethrough. Also during the downstroke, the ball in the standing valve seats, preventing pumped oil from moving back down into the hole. The process repeats itself again and again, with oil essentially being moved in stages from the hole, to above the standing valve and in the oil pump, to above the traveling valve and out of the oil pump. As the oil pump fills, the oil passes through the pump and into the tubing. As the tubing is filled, the oil passes into the flow line, and is then taken to the storage tank or other such structure. 
     A number of problems can occur with fluid and gas production from wells. Fluid that is pumped from the ground typically includes solid impurities, as well as water and gas. With respect to naturally flowing wells, when relatively large volumes of water or other fluid enter the formation, the weight of this fluid can create a plug effect in the tubing, thereby slowing down or even prematurely shutting off the flow of gas to the surface. In order to continue gas flow, mechanical means, such as a pumping system, would then be required. 
     Furthermore, once the natural pressure in the well has depleted and a pumping system is employed to remove the subterranean fluid and gas, other problems can occur. When the pumping system is actuated, fluid and gas migrate from the wellbore to the pumping system&#39;s intake, which comprises an area of relatively lower pressure than that of the formation. Gas that enters the pumping system can cause a condition known as “gas lock,” and can slow down or even shut down production. Intake areas of pumping systems generally include nipple or strainer devices to help control the amount of gas that enters the pumping system. Often, however, gas is still allowed to enter, such that the intake of fluid is substantially reduced or even halted resulting in undesired affects. 
     The present application addresses these issues encountered in fluid and gas production and provides other, related, advantages. 
     SUMMARY 
     This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the DESCRIPTION OF THE APPLICATION. This summary is not intended to identify key features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter. 
     In accordance with one embodiment of the present application, a cyclonic strainer is provided. The cyclonic strainer can include an elongated member having a channel formed longitudinally therein. In addition, the cyclonic strainer can include a plurality of apertures extending through the elongated member angled downwardly into the channel and away from a center of the channel. 
     In accordance with another embodiment of the present application, a method for controlling gas from entering into a pump system is provided. The method can include providing a cyclonic strainer comprising: an elongated member having a channel formed longitudinally therein; and a plurality of apertures extending through said elongated member angled downwardly into said channel and away from a center of said channel; coupling said cyclonic strainer to a subsurface pump; utilizing said subsurface pump, pumping fluid; and centrifuging said fluid against an interior wall of said strainer and allowing gas to be driven through a center of said strainer with said gas being diverted northward to a surface. 
     In accordance with yet another embodiment of the present application, an apparatus is provided. The apparatus can include a cylinder with a channel formed therein. In addition, the apparatus can include a tubing string coupled to a north end of the cylinder. The apparatus can also include a plurality of ports on a body of the cylinder angled southward to the channel in a direction away from a center of the channel. The apparatus can include a tail pipe coupled to a south end of the cylinder. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The novel features believed to be characteristic of the application are set forth in the appended claims. In the descriptions that follow, like parts are marked throughout the specification and drawings with the same numerals, respectively. The drawing figures are not necessarily drawn to scale and certain figures can be shown in exaggerated or generalized form in the interest of clarity and conciseness. The application itself, however, as well as a preferred mode of use, further objectives and advantages thereof, can be best understood by reference to the following detailed description of illustrative embodiments when read in conjunction with the accompanying drawings, wherein: 
         FIG. 1  is a perspective view of an exemplary cyclonic strainer, in accordance with an embodiment of the present application; 
         FIG. 2  is a side view of the exemplary cyclonic strainer of  FIG. 1 ; 
         FIG. 3  is a cross-sectional view of the exemplary cyclonic strainer, taken through line  3 - 3  of  FIG. 2 ; 
         FIG. 4  is a cross-sectional view of the exemplary cyclonic strainer, taken through line  4 - 4  of  FIG. 2 ; 
         FIG. 5  is a cross-sectional view of the exemplary cyclonic strainer, taken through line  5 - 5  of  FIG. 3 ; 
         FIG. 6  is a top view of the exemplary cyclonic strainer of  FIG. 1 , with ports thereof shown in phantom; 
         FIG. 7  is a bottom view of the exemplary cyclonic strainer of  FIG. 1 , with ports thereof shown in phantom; 
         FIG. 8  is a perspective view of an exemplary plug component to be utilized with the cyclonic nipple device, in accordance with an embodiment of the present application; 
         FIG. 9  is a side view of the exemplary plug component of  FIG. 8 ; 
         FIG. 10  is another side view of the exemplary plug component of  FIG. 8 ; 
         FIG. 11  is a cross-sectional view of the exemplary plug component, taken through line  11 - 11  of  FIG. 10 ; 
         FIG. 12  is a top view of the exemplary plug component of  FIG. 8 ; 
         FIG. 13  is a bottom view of the exemplary plug component of  FIG. 8 ; 
         FIG. 14  is a side view of an embodiment of an exemplary pumping apparatus having the exemplary cyclonic strainer of the present application positioned thereon; and 
         FIG. 15  is side view of an exemplary cyclonic strainer, in accordance with an embodiment of the present application. 
     
    
    
     DESCRIPTION OF THE APPLICATION 
     The foregoing description is provided to enable any person skilled in the relevant art to practice the various embodiments described herein. Various modifications to these embodiments can be readily apparent to those skilled in the relevant art, and generic principles defined herein can be applied to other embodiments. Thus, the claims are not intended to be limited to the embodiments shown and described herein, but are to be accorded the full scope consistent with the language of the claims, wherein reference to an element in the singular is not intended to mean “one and only one” unless specifically stated, but rather “one or more.” All structural and functional equivalents to the elements of the various embodiments described throughout this disclosure that are known or later come to be known to those of ordinary skill in the relevant art are expressly incorporated herein by reference and intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. 
     The present application relates to a cyclonic strainer for a well intake that provides for improved separation of gas and fluid. The strainer can include an elongated member having a channel formed longitudinally therein. A plurality of apertures can extend through the elongated member angled downwardly into the channel and away from a center of the channel allowing for a better shear between gas and fluids. The angle of the ports can cause fluid to be forced in an opposite direction, resulting in gases and fluids shearing more quickly and cleanly, due to kinetic energy. The angle of the ports can be varied to accommodate different conditions in various well environments. In well environments in which gaseous conditions are extreme, it can be desired for the ports to be sloped southwardly or downwardly at a greater angle than for well environments in which gaseous conditions are not as extreme. 
     Turning now to  FIGS. 1-4 , a cyclonic strainer device (“cyclonic strainer  10 ”) consistent with an embodiment of the present application is shown. In describing the structure of the cyclonic strainer  10  and its operation, the terms “north” and “south” are utilized. The term “north” is intended to refer to that end of the cyclonic strainer  10  that is more proximate the pumping unit, while the term “south” is intended to refer to that end of the cyclonic strainer  10  that is more distal the pumping unit, or “down hole.” Furthermore, while strainer and/or nipple  10  are used herein, those skilled in the relevant art will appreciate that other terms can be interchanged and are within the scope of this application. 
     The cyclonic strainer  10  generally includes a substantially cylindrical shaped device having a north end  12 , a body  14 , a south end  16 , and a longitudinal channel  18  running therethrough. The cyclonic strainer  10  can be constructed of various lengths, as can be desired for various well configurations and conditions. The body  14  of the cyclonic strainer  10  can include an exterior wall  20  and an interior wall  22 . The cyclonic strainer  10  is preferably a one-piece structure, although it can be desired for various components of the cyclonic strainer  10  to be separate pieces that can be coupled together to form a one-piece unit. The cyclonic strainer  10  is preferably composed of a hardened material capable of withstanding conditions present in typical well environments. In a preferred embodiment, the cyclonic strainer  10  is composed of brass. However, other suitable materials can be used for the cyclonic strainer  10 . 
     In one embodiment, the cyclonic strainer  10  is adapted to be coupled at its north end  12  to a southern portion of a subsurface pump  100  as shown in  FIG. 14 , for example, and further discussed below. In such an embodiment, the cyclonic strainer  10  thus forms an intake area. In one embodiment, threading  24  is provided proximate the north end  12  of the cyclonic strainer  10  for coupling to the subsurface pump  100 . However, any other suitable coupling means known in the relevant art can be employed for coupling the cyclonic strainer  10  to a subsurface pump. While in this embodiment threading  24  is provided at an interior diameter of the cyclonic strainer  10 , it can be desired to provide threading at an exterior diameter of the cyclonic strainer  10 . In this embodiment, wrench flats  26  are included at the north end  12  of the cyclonic strainer  10 , to assist with coupling the cyclonic strainer  10  to a subsurface pump. However, it would be possible to construct a cyclonic strainer  10  with the wrench flats  26  omitted. 
     A shoulder  28  can also be included proximate the north end  12 . In this embodiment, as shown in  FIG. 3 , for example the shoulder  28  can be positioned southward of threading  24 . When the cyclonic strainer  10  is positioned on the subsurface pump  100 , the shoulder  28  abuts a southern portion of the seating strainer section  126 , thereby rendering a tight fit of cyclonic strainer  10  on the subsurface pump  100 . 
     The body  14  of the cyclonic strainer  10  can include a plurality of ports  30 , each of which communicates from the exterior of the cyclonic strainer  10  to the channel  18 . Ports  30  can also be referred to as openings, holes, gaps, apertures, etc. The body  14  of the cyclonic strainer  10  can have virtually any number of ports  30 , as can be desired for various well configurations and conditions. In one embodiment, the ports  30  are evenly spaced around the cyclonic strainer  10  vertically and/or horizontally. Preferably, from the perspective of the exterior of the cyclonic strainer  10 , each port  30  can be angled southwardly or downwardly from the exterior of the cyclonic strainer  10  to the channel  18  in a direction away from a center  32  of the channel  18  of the cyclonic strainer  10  as shown in  FIGS. 6 and 7 . 
     In one embodiment, each port  30  can slope downwardly at an angle of up to sixty (60) degrees. Likewise, from the perspective of the channel  18 , each port  30  is preferably angled northwardly or upwardly from the channel  18  to the exterior of the cyclonic strainer  10 . In another embodiment, each port  30  can slope southwardly or downwardly at an angle ranging from zero (0) up to and including sixty (60) degrees. Such an orientation of the ports  30  allows for a better shear between gas and fluids. In this regard, due to a variety of factors including gravity and the heavier weight of the fluids compared to gas, the gas naturally tends to float upward. The angle of the ports  30  causes fluid to be forced in the opposite direction, resulting in gases and fluids shearing more quickly and cleanly, due to kinetic energy. The angle of the ports  30  could be varied to accommodate different conditions in various well environments, depending upon the nature and severity of any gaseous conditions that can be present. In well environments in which gaseous conditions are extreme, for example, it can be desired for the ports  30  to be sloped southwardly or downwardly at a greater angle than for well environments in which gaseous conditions are not as extreme. By having a greater angle, gases are prevented from escaping back through the ports  30 . 
     As shown in this embodiment and seen particularly in  FIGS. 5-7 , each port  30  is thus offset from the center  32  of the channel  18  of the cyclonic strainer  10 . This orientation of the ports  30  imparts a cyclonic rotation on fluids as they pass through the ports  30  and travel northward. Fluids are centrifuged against the interior wall  22  of the cyclonic strainer  10 , which directs gas toward the center  32  of the channel  18 , allowing the gas to be produced through the channel  18  and to continue northward through the tubing in the direction of the surface. 
     The south end  16  of the cyclonic strainer  10  can include a tail pipe  34 . Preferably, the outer diameter of the cyclonic strainer  10 , in the area of the body  14  is greater than the outer diameter of the cyclonic strainer  10  in the area of the tail pipe  34 . However, it would be possible to provide a cyclonic strainer  10  in which the outer diameter in the area of the body  14  can be the same as the outer diameter in the area of the tail pipe  34 . The tail pipe  34  is adapted to be positioned in fluid in a well. Preferably, when the tail pipe  34  is positioned in such fluid, the fluid level of the well typically reaches a northern-most portion  36  of the tail pipe  34 . 
     Referring now to  FIG. 14 , a subsurface pump  100  having an embodiment of a cyclonic strainer  10  positioned thereon is shown. In this embodiment, the cyclonic strainer  10  is shown coupled, at its north end  12 , to a southern portion of the subsurface pump  100 , south of a seating strainer section  126  thereof. In this embodiment, the subsurface pump  100  generally comprises several components. The shaft can be lined with tubing  110 . A valve rod or hollow valve rod  112  can pass through or is attached to a rod guide  114 , and is coupled at its south end to a plunger adapter  116 , which is coupled to a pump plunger  118 . The pump plunger  118 , in turn, can be coupled to a traveling valve  120 , to which is coupled a seat plug  122 . 
     South of the traveling valve  120  is a standing valve  124 . South of the standing valve  124  is a seating strainer section  126  and a cyclonic strainer  10  coupled thereto. The portion of the valve rod  112  that passes through or is attached to the rod guide  114 , along with the plunger adapter  116 , pump plunger  118 , traveling valve  120 , and seat plug  122  can be positioned within a pump barrel  128 . The southern portion of the subsurface pump  100  can be anchored in a southern portion of the tubing  110 . One skilled in the relevant art will appreciate that fewer or more components can be added to the subsurface pump  100 . 
     Initially, fluid and gas enter the wellbore from the formation. When the subsurface pump  100  is actuated, fluid and gas migrate from the wellbore to the intake area of the subsurface pump  100 , where the cyclonic strainer  10  is situated, which comprises an area of relatively lower pressure than that of the formation. The outer boundary of the gas can naturally have surface tension. In operation, on the upstroke, fluid is drawn into the tail pipe  34  and ports  30  of the cyclonic strainer  10 . Gas can also be drawn toward the ports  30 . 
     When the fluid and gas reach the ports  30 , the gas can be strained away from the fluid and, as a result of the natural surface tension on the gas, then travels northward, bypassing the ports  30 . Although some gas can enter the ports  30 , often most of it is separated from the fluid as it enters the ports  30 , thereby preventing the gas from entering the subsurface pump  100 . The orientation of the ports  30 , as discussed above, imparts a cyclonic rotation on fluids as they pass through the ports  30  and travel northward. This cyclonic rotation causes fluid to be centrifuged against the interior wall  22  of the cyclonic strainer  10 , which makes way for and allows gas that has entered the ports  30  to be produced through the center  32  of the channel  18 , where such gas then travels northward, in the direction of the surface. 
     Referring now to  FIGS. 8-13 , a plug component, hereinafter plug  50 , is shown. The plug  50  can be utilized with the cyclonic strainer  10 . The plug component  50  is adapted to be inserted in a southern portion of the channel  18  of the cyclonic strainer  10  at the south end  16 . When utilized with the cyclonic strainer  10 , the plug component  50  can regulate fluid intake by blocking the tail pipe  34 , thereby closing it off and preventing fluid from entering the cyclonic strainer  10  through the tail pipe  34 . In this way, fluid enters the cyclonic strainer  10  only through the ports  30 . 
     The plug component  50  can include a north end  56 , a body  54 , and a south end  52 . The south end  52  can include a hollowed-out portion  58 . The body  54  tapers northwardly toward the north end  56 , which can permit the plug component  50  to be positioned in the tail pipe  34  of the cyclonic strainer  10 . Wrench flats  60  can be provided on the plug component  50 , as shown in this embodiment, to assist with positioning the plug component  50  in the tail pipe  34 . However, the wrench flats  60  can be omitted. Like the cyclonic strainer  10 , the plug component  50  is preferably composed of a hardened material capable of withstanding conditions present in typical well environments. In a preferred embodiment, the plug component  50  is composed of brass. However, other suitable materials can be used for the plug component  50 . 
     Referring now to  FIG. 15 , another embodiment of a cyclonic strainer device (“cyclonic strainer  200 ”) consistent with an embodiment of the present application is shown. The cyclonic strainer  200  is somewhat similar to the cyclonic strainer  10 , but is adapted for use with a naturally flowing gas well. 
     The cyclonic strainer  200  generally comprises a substantially cylindrical shaped device having a north end  212 , a body  214 , a south end  216 , and a longitudinal channel  218  running therethrough. The cyclonic strainer  200  can be constructed at various lengths, as can be desired for various well configurations and conditions. The body  214  of the cyclonic strainer  200  can include an exterior wall and an interior wall  222 . The cyclonic strainer  200  is preferably a one-piece structure, although it can be desired for various components of the cyclonic strainer  200  to be separate pieces that can be coupled together to form a one-piece unit. The cyclonic strainer  200  is preferably composed of a hardened material capable of withstanding conditions present in typical well environments. In a preferred embodiment, the cyclonic strainer  200  is composed of brass. However, other suitable materials can be used for the cyclonic strainer  200 . 
     In one embodiment, the cyclonic strainer  200  is adapted to be coupled, at its north end  212 , to a southern portion of a tubing string  300 . In such an embodiment, the cyclonic strainer  200  thus forms an intake area. In one embodiment, female threading can be provided proximate the north end  212  of the cyclonic strainer  200  for coupling to the tubing string  300 , in similar fashion to the threading  24  utilized on the north end  12  of the cyclonic strainer  10 . Alternatively, it can be desired to employ male threading in this region. However, any other suitable coupling means known in the art can be employed for coupling the cyclonic strainer  200  to the tubing string  300 . 
     The body  214  of the cyclonic strainer  200  can include a plurality of ports  230 , each of which communicates from the exterior of the cyclonic strainer  200  to the channel  218 . The body  214  of the cyclonic strainer  200  can have virtually any number of ports  230 , as can be desired for various well configurations and conditions. Preferably, from the perspective of the exterior of the cyclonic strainer  200 , each port  230  is angled southwardly or downwardly from the exterior of the cyclonic strainer  200  to the channel  218 , in a direction away from a center of the channel  218  of the cyclonic strainer  200 , in similar fashion to the orientation of the ports  30  of the cyclonic strainer  10  shown in  FIGS. 6 and 7 , for example. In one embodiment, each port  230  slopes downwardly at an angle of up to sixty (60) degrees. Likewise, from the perspective of the channel  218 , each port  230  is preferably angled northwardly or upwardly from the channel  218  to the exterior of the cyclonic strainer  200 . 
     In another embodiment, each port  230  can slope southwardly or downwardly at an angle ranging from zero (0) up to and including sixty (60) degrees. Such an orientation of the ports  230  allows for a better shear between gas and fluids. In this regard, due to a variety of factors including gravity and the heavier weight of the fluids compared to gas, the gas naturally tends to float upward. The angle of the ports  230  causes fluid to be forced in the opposite direction, resulting in gases and fluids shearing more quickly and cleanly, due to kinetic energy. The angle of the ports  230  could be varied to accommodate different conditions in various well environments, depending upon the nature and severity of any gaseous conditions that can be present. In well environments in which gaseous conditions are extreme, for example, it can be desired for the ports  230  to be sloped southwardly or downwardly at a greater angle than for well environments in which gaseous conditions are not as extreme. 
     Preferably, each port  230  is thus offset from the center of the channel  218  of the cyclonic strainer  200 , in similar fashion to the ports  30  of the cyclonic strainer  10 . Such an orientation of the ports  230  imparts a cyclonic rotation on fluids as they are drawn northward through the cyclonic strainer  200  and then northward through the tubing string  300 . In this way, fluids are centrifuged against the interior wall  222  of the cyclonic strainer  200 , which allows an opening to be created in the center of the channel  218  for gas to escape. Thus, gas is permitted to be produced through the channel  218  and to continue northward through the tubing string  300  in the direction of the surface. 
     The south end  216  of the cyclonic strainer  10  can include a tail pipe  234 . The tail pipe  234  is adapted to be positioned in fluid in a well. Preferably, when the tail pipe  234  is positioned in such fluid, the fluid level of the well reaches a northern-most portion  236  of the tail pipe  34 . It is important to note that the cyclonic rotation discussed above also provides a benefit of causing fluids, especially any water present in the formation, to be siphoned slowly into the tail pipe  234 , preventing overload from occurring and shutting down production. 
     In operation, fluid and gas can enter the wellbore from the formation. Natural formation pressure can force such fluid and gas through the cyclonic strainer  200  and northward through tubing string  300 . Fluid and gas are first drawn into the tail pipe  234  and ports  230  of the cyclonic strainer  200 . When the fluid and gas reach the ports  230 , cyclonic rotation imparted by virtue of the orientation of the ports  230  forces the fluid against the interior wall  222  of the cyclonic strainer  200 . This cyclonic rotation causes fluid to be centrifuged against the interior wall  222 , which makes way for and allows any gas that has entered the cyclonic strainer  200  to be produced through the center of the channel  18 , where such gas will then travel northward through the tubing in the direction of the surface. 
     The foregoing description is provided to enable any person skilled in the relevant art to practice the various embodiments described herein. Various modifications to these embodiments can be readily apparent to those skilled in the relevant art, and generic principles defined herein can be applied to other embodiments. Thus, the claims are not intended to be limited to the embodiments shown and described herein, but are to be accorded the full scope consistent with the language of the claims, wherein reference to an element in the singular is not intended to mean “one and only one” unless specifically stated, but rather “one or more.” All structural and functional equivalents to the elements of the various embodiments described throughout this disclosure that are known or later come to be known to those of ordinary skill in the relevant art are expressly incorporated herein by reference and intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims.