JP2004537669A - Fluid controlled pump system and method - Google Patents

Abstract

The fluid controlled pump system includes a pump unit (12) disposed within a fluid cavity (13). The pump unit (12) includes a passage (60) extending to the suction end of the pump unit. The system also includes a pressure source (72) coupled to the passage (60) and operable to push fluid outward from the passage near the suction end (34) of the pump unit. The system includes a pressure sensor (74) coupled to the passage (60). The system further includes a controller (76) coupled to the pump unit (12) and operable to adjust operating parameters of the pump unit using the fluid pressure. The fluid level controlled pump system includes a pump unit disposed within the fluid cavity. The pump unit includes an inlet (118) operable to receive the fluid to be pumped from the fluid cavity. The system also includes a valve (140) slidably coupled to the pump unit. The valve (140) includes a passage (160) for receiving the pumped fluid from the outlet (122) of the pump unit. In response to a decrease in the fluid level in the fluid cavity, the movement of the valve relative to the pump unit aligns the passage (160) with the port of the pump unit to circulate the pumped fluid from the outlet to the inlet.

Description

【Technical field】
[0001]
The present invention relates generally to the field of fluid pump systems, and more particularly to fluid controlled pump systems and methods.
[Background Art]
[0002]
Pump units are used in a variety of applications for compressing, lifting and transferring fluids. For example, the pump unit may be used for municipal water and sewage business applications, mining and / or hydrocarbon utilization and production applications, hydraulic motor applications, and consumer product manufacturing applications. Pump units, such as progressive cavity pumps, centrifugal pumps, and other types of pumping devices, are typically located in a fluid and are compressed between different heights to compress the fluid, i.e., to increase the pressure of the fluid. Used to push fluids up or to transfer fluids between various destinations.
[0003]
However, conventional pump units have several disadvantages. For example, conventional pump units generally require some form of lubrication to remain usable. For example, progressive cavity pumps typically include a rotor disposed within a rubber stator. In operation, rotational force is imparted to the rotor, thereby creating a corkscrew-like effect between the rotor and stator to lift fluid from one level to another. In the case of a progressive cavity pump, the friction created by rotation of the rotor with respect to the stator without fluid lubrication often causes the progressive cavity pump to fail in a relatively short time. Generally, the fluid being pumped will provide the desired lubrication. However, changes in fluid level near the inlet of the pump unit can result in no fluid lubrication for the pump unit. Thus, maintaining proper fluid lubrication in the pump unit is important for pump operation performance and life. Further, in centrifugal pump applications, the absence of fluid to be pumped can cause cavitation.
DISCLOSURE OF THE INVENTION
[Problems to be solved by the invention]
[0004]
Therefore, there is a need for an improved pump system with improved control of the fluid lubrication of the pump unit. The present invention provides a fluid controlled pump system and method that addresses the shortcomings of the prior art pump systems and methods.
[Means for Solving the Problems]
[0005]
According to one embodiment of the present invention, a fluid controlled pump system includes a pump unit disposed within a fluid cavity. The pump unit includes a passage extending to the head of the pump unit. The system also includes a pressure source coupled to the passage and operable to push fluid outwardly from the head of the pump unit through the passage. The system also includes a pressure sensor coupled to the passage and operable to measure a pressure of the fluid in the passage. The system further includes a controller coupled to the pump unit and operable to adjust an operating parameter of the pump unit in response to the fluid pressure.
[0006]
According to another embodiment of the present invention, a method for fluid-controlled pump operation includes providing a pump unit disposed within a fluid cavity. The pump unit includes a passage extending to the head of the pump unit. The method also includes pushing fluid outwardly from the head of the pump unit through the passage and measuring the pressure of the fluid in the passage. The method also includes automatically adjusting an operating parameter of the pump unit in response to the fluid pressure.
[0007]
According to another embodiment of the present invention, a fluid controlled pump system includes a pump unit disposed within a fluid cavity. The pump unit includes an inlet operable to receive the fluid to be pumped from the fluid cavity. The system also includes a valve slidably coupled to the pump unit. The valve includes a passage for receiving pump fluid from the pump unit. The valve further moves with respect to the pump unit as the fluid level in the fluid cavity decreases to match the valve passage with the port of the pump unit to circulate pumped fluid to the inlet of the pump. It is operable to
[0008]
According to another embodiment of the present invention, a fluid-level controlled pump method includes providing a progressive cavity pump disposed within a fluid cavity. The pump includes a stator / rotor portion for pumping a fluid located within the fluid cavity. The stator / rotor section includes an inlet and an outlet. The method also includes providing a valve coupled to the pump. The valve is operable to receive fluid from the stator / rotor section. The method further includes automatically circulating fluid from the outlet to the inlet via the valve in response to a decrease in the fluid level in the fluid cavity.
[0009]
According to yet another embodiment of the present invention, a fluid level controlled pump system includes a progressive cavity pump disposed within a fluid cavity. The pump includes a stator / rotor portion for pumping a fluid located within the fluid cavity. The stator / rotor section includes an inlet and an outlet. The system also includes a valve coupled to the pump and positioned to communicate with the outlet. The valve is operable to circulate fluid from the outlet to the inlet in response to a decrease in fluid level in the fluid cavity.
[0010]
The present invention has several technical advantages. For example, in one embodiment of the invention, the system monitors a fluid pressure in the fluid cavity corresponding to a level of the fluid in the fluid cavity. Based on the fluid pressure, the system controls the operating parameters of the pump unit to ensure correct fluid lubrication during operation. Thus, as the fluid level decreases in the fluid cavity, the operating parameters of the pump unit can be changed. For example, in response to a decrease in the fluid level in the fluid cavity, the operating speed of the pump unit may also decrease, thereby maintaining a substantially constant fluid level in the fluid cavity to provide the desired pump unit lubrication. Further, operation of the pump unit can be stopped based on the fluid level in the fluid cavity to substantially prevent operation of the pump unit without fluid lubrication.
[0011]
Other technical advantages of the present invention include providing a flush function that substantially prevents accumulation of material at the inlet of the pump unit. For example, a progressive cavity pump may include an internal passage extending downward from a rotor of the pump and having an outlet located near an inlet of the pump. Fluid may be provided downward in the passageway outward from the passageway outlet to flush the accumulation of material from the inlet of the pump and, if desired, maintain the suspension of the material in the pumped fluid.
【The invention's effect】
[0012]
The present invention also offers several technical advantages. For example, in one embodiment of the invention, fluid lubrication of the pump unit is maintained by circulating pumped fluid to the pump unit inlet in response to changes in fluid level within the fluid cavity. For example, according to one embodiment of the present invention, the valve is located near the pump unit to circulate the pumped fluid to the inlet of the pump unit. Thus, as the fluid level falls within the fluid cavity, the valve circulates pumped fluid to the pump unit inlet to substantially prevent operation of the pump unit without fluid lubrication. In one embodiment, the valve may be slidably coupled to the pump unit, thereby providing movement of the valve relative to the pump unit in response to a change in fluid level in the fluid cavity.
[0013]
Other technical advantages of the present invention include increasing the reliability of the pump unit without requiring costly user intervention. For example, according to one embodiment of the invention, the valve is slidably coupled to the pump unit, thereby providing upward and downward movement of the valve in response to changes in fluid level within the fluid cavity. The valve circulates or returns pumped fluid to the pump unit inlet to ensure lubrication of the pump unit in response to a decrease in fluid level in the fluid cavity.
[0014]
Other technical advantages will be readily apparent to one skilled in the art from a reading of the drawings, detailed description, and claims.
BEST MODE FOR CARRYING OUT THE INVENTION
[0015]
For a more complete understanding of the present invention and its advantages, the following description is provided in connection with the accompanying drawings. FIG. 1 is a diagram illustrating a fluid controlled pump system 10 according to one embodiment of the present invention. In the embodiment of FIG. 1, system 10 is shown for mining and / or hydrocarbon production applications. However, it should be understood that the system 10 can be used for other pumping applications. The system 10 includes a pump unit 12 that extends to a fluid cavity 13. The fluid cavity 13 generally contains the fluid to be compressed, lifted or transferred. Thus, in the illustrated embodiment, the pump unit 12 extends downward from the surface 14 to the wellbore 16. In this embodiment, the pump unit 12 includes a progressive cavity pump 18. However, it should be understood that other types of pump units 12 incorporating the teachings of the present invention may be used.
[0016]
Pump 18 includes a base 20 located on surface 14 and a stator / rotor portion 22 located in wellbore 16. Stator / rotor portion 22 includes a stator 24 coupled to an inner surface 26 of housing 28. The stator / rotor portion 22 also causes the rotation of the rotor 30 relative to the stator 24 to create a corkscrew effect, thereby pumping a fluid 32 located in the cavity 13 or well bore 16 to the surface 14. Or includes a rotor 30 disposed within the stator 24 for frying. In this embodiment, fluid 32 may include water, hydrocarbon compounds, boring mud, shavings, and other materials that are generally lifted from well bore 16 to surface 14. However, fluid 32 may include other materials that may be commonly handled in certain pumping applications.
[0017]
In operation, the suction end 34 of the stator / rotor portion 22 causes the rotation of the rotor 30 with respect to the stator 24 to move the fluid 32 upward through an inlet 36 formed between the rotor 30 and the stator 24. It is arranged in the well hole 16 to be pulled out. Fluid 32 travels upwardly through stator / rotor portion 2 and exits at discharge end 38 of stator / rotor portion 22 through an outlet 40 formed between stator 24 and rotor 30. Fluid 32 travels upward in an annular portion 42 formed between housing 28 and drive shaft 44. The lower end 46 of the drive shaft 44 is coupled to the upper end 48 of the rotor 30 to provide rotational movement of the rotor 30 with respect to the stator 24. Fluid 32 traveling upwardly through the annulus 42 is directed outwardly from the annulus 42 through the discharge port 50 to a mud pit or other location (not shown). For example, fluid 32 may be directed through discharge port 50 to a separator (not shown) for separating hydrocarbons and / or other materials from water. However, it should be understood that fluid 32 may be directed from discharge port 50 to other suitable processing systems.
[0018]
The wellbore 16 also includes a discharge port 52 that directs gas or other material out of the wellbore 16. For example, gas located within wellbore 16 may travel upward through an annular portion 54 formed between housing 28 and both wellbore 16 of housing 20 and housing 56. Thus, gas in wellbore 16 may be directed upward toward surface 14 and released through port 52 to be burned (flared) or to accommodate other suitable processing requirements.
[0019]
As shown in FIG. 1, the pump unit 12 also includes a hollow passage 60 that extends downward through the drive shaft 44 and the rotor 30. The passage 60 includes an open end 62 near the suction end 34 of the stator / rotor portion 22 so that the depth 64 of the fluid 32 in the well bore 16 for the pump unit 12 can be monitored. The use of the passage 60 will be described in detail below.
[0020]
System 10 also includes an air pressure source 72, a pressure sensor 74, a controller 76, and a drive motor 78. A pressure source 72 is coupled to the passage 60 through the upper end 80 of the pump unit 12 to direct the pressurized fluid downward in the passage 60. Pressure source 72 may include carbon dioxide, nitrogen, air, methane, or other suitable pressurized fluid. Pressure sensor 74 is also coupled to passage 60 for measuring fluid pressure in passage 60.
[0021]
In operation, pressure source 72 causes passage 60 to pass a relatively small or controlled amount or volume of pressurized fluid out of open end 62 of passage 60, as generally indicated by reference numeral 90. Provide a downwardly pressurized fluid into the interior. For example, the pressure source 72 may be maintained at a pressure substantially greater than the pressure of the fluid 32 in the wellbore 16 and the orifice throttle valve 82 may be coupled to the pressure source 72 such that the friction pressure is generally negligible. However, other suitable methods and devices may be used to maintain a controlled amount or volume of pressurized fluid exiting the open end 62 of the passage 60.
[0022]
Pressure sensor 74 is used to measure the pressure in passage 60 required to expel pressurized fluid from open end 62 of passage 60. As shown in FIG. 1, the pressure required to expel outwardly pressurized fluid from the open end 62 of the passage 60 depends on the level or depth of the fluid 32 generally near the inlet 36 of the pump unit 12. 64. Thus, the pressure in passage 60 can be used to measure depth 64 of fluid 32 near inlet 36 of pump unit 12.
[0023]
As further shown in FIG. 1, pressure sensor 74 is coupled to controller 76. Controller 76 may include a processor, minicomputer, workstation, or other type of processing device for receiving a signal from pressure sensor 74 corresponding to the pressure in passage 60. The signal received from sensor 74 by controller 76 may include a continuous data stream or may include a periodic data signal. Controller 76 receives the signal from sensor 74 and monitors the fluid pressure in passage 60. Based on the pressure in passage 69, controller 76 adjusts the operating parameters of pump unit 12.
[0024]
For example, as shown in FIG. 1, the controller 76 is coupled to a drive monitor 78 for controlling operating parameters of the pump unit 12. As shown in FIG. 1, drive motor 78 includes a belt 92 coupled between drive motor 78 and drive shaft 44 near upper end 80 of pump unit 12 to rotate rotor 30 relative to stator 24. And imparts a rotational force to the drive shaft 44 via. In this manner, controller 76 controls the rotational force applied to drive motor 78 based on the pressure signal received from pressure sensor 74, thereby controlling the flow rate of fluid 32 to surface 14. For example, in operation, drive motor 78 receives a control signal from controller 76 to adjust the rotational force imparted to drive shaft 44 by drive motor 78.
[0025]
Thus, in operation, the operating parameters of the pump unit 12 may vary with the change in the amount of fluid 32 in the wellbore 16 to substantially prevent the pump unit 12 from operating in a "dry" or unlubricated situation. Will be changed accordingly. For example, as shown in FIG. 1, a pressure source 72 is provided within the passage 60 such that a relatively small or controlled amount or volume of pressurized fluid exits the open end 62 of the passage 60 near the suction end 34. To a fluid pressurized downward. As the depth 64 of the fluid 32 in the well bore 16 changes, the pressure in the passage 60 required to expel the pressurized fluid outward from the open end 62 of the passage 60 also changes. Based on the change in pressure in passage 60, controller 76 adjusts the operating parameters of pump unit 12 via drive motor 78. Thus, as the depth 64 of the fluid 32 in the wellbore 16 decreases, the pressure in the passage 60 required to expel the pressurized fluid outward from the open end 62 also correspondingly decreases. In response to the decrease in pressure in passage 60, controller 76 automatically reduces the rate of rotation of drive shaft 44 provided by drive motor 78, thereby reducing the flow rate of fluid 32 removed from well bore 16. Thus, the rate of rotation of the drive shaft 44 is reduced or stopped in response to a decrease in the level of the fluid 32 in the well 16, thereby reducing the velocity of the fluid 32 flowing out of the well 16 and Operation of the pump unit 12 without proper lubrication is substantially prevented. Further, by adjusting the operating parameters of the pump unit 12 based on the level of the fluid 32 in the well 16, the present invention also provides a means for maintaining a substantially constant level of the fluid 32 in the well 16.
[0026]
Accordingly, the system 10 can also be used to increase the rate of rotation of the drive shaft 44 in response to increasing the depth 64 of the fluid 32 in the well 16, thereby increasing the flow rate of the fluid 32 from the well 16. Enhance. For example, as the depth 64 of the fluid 32 increases in the wellbore 16, the pressure required to expel fluid outwardly from the open end 62 of the passage 60 also increases. In response to the increase in pressure in passage 60, controller 76 adjusts drive motor 78 to provide additional rotational force to drive shaft 44, thereby providing an increased pump volume of fluid 32 to surface 14.
[0027]
Accordingly, the present invention enhances control of the pumping of fluid 32 from well 16 to surface 14 based on the amount or depth 64 of fluid 32 in well 16. As the depth 64 of the fluid 32 increases or decreases, the controller 76 adjusts the operating parameters of the pump unit 12 via the drive motor 78, thereby causing a corresponding increase or decrease in the rotational speed of the drive shaft 44, respectively. . Accordingly, the present invention increases pumping of fluid 32 as well as the level of fluid 32 in wellbore 16 increases, and / or as the amount of fluid 32 in wellbore 16 decreases. Can be used to reduce or stop the pumping of the fluid 32 from the wellbore 16.
[0028]
The present invention may also provide for flushing or mixing of the fluid 32 within the fluid cavity 13 to substantially prevent or eliminate accumulation of material at the inlet 36 of the pump unit 12. For example, a periodic outward and downward passage near the suction end 34 of the pump unit 12 through the passage 60 to substantially prevent accumulation of material at the inlet 36 and maintain a suspension of the material within the fluid 32. A solenoid valve 96 or other suitable device may be used to provide a suitable fluid pressure burst.
[0029]
FIG. 2 is a diagram illustrating a fluid controlled pump system 100 according to another embodiment of the present invention, and FIG. 3 is a diagram of FIG. 2 after a decrease in the level of fluid 102 in well hole 104 according to an embodiment of the present invention. FIG. In this embodiment, the system 100 includes a pump unit 106 disposed in the well 104 to pump the fluid 102 in the well 104 to a surface. Pump unit 106 shown in FIGS. 2 and 3 includes a progressive cavity pump 108. However, it should be understood that other types of pump units 106 according to the teachings of the present invention may also be used.
[0030]
As described above with respect to FIG. 1, the progressive cavity pump 108 includes a stator / rotor portion 110 for lifting the fluid 102 in the wellbore 104 to a surface. For example, as shown in FIGS. 2 and 3, the stator / rotor portion 110 includes a rotor 112 that is coupled to a drive shaft 114 that is rotatable within a stator 116 of the pump 108. Thus, rotation of rotor 112 relative to stator 116 is such that corkscrew-like movement of rotor 112 relative to stator 116 lifts fluid 102 through stator / rotor portion 110 and exits 120 of stator / rotor portion 110. Withdraw fluid 102 through inlet 118 of stator / rotor portion 110 to expel fluid 102 outwardly from. The fluid 102 then travels upward from the discharge end 122 of the stator / rotor portion 110 to the surface via an annulus 124 formed between the drive shaft 114 and the housing 126 of the pump unit 106.
[0031]
In this embodiment, the system 100 also includes a valve 140 located around the housing 126 of the pump unit 106, and a check valve 142 located near the suction end 144 of the pump unit 106. Valve 140 is slidably coupled to housing 126 of pump unit 106 such that a change in the level of fluid 102 in well hole 104 causes a corresponding upward or downward movement of valve 140 relative to pump unit 106. Further, in this embodiment, valve 140 is a fluid, foam, or other substance having a density substantially less than the density of fluid 102 such that valve 140 floats within fluid 102 relative to pump unit 106. Can be satisfied. Thus, for example, the interior chamber 146 may be filled with nitrogen, carbon dioxide, bubbles, or any other suitable fluid or substance having a density substantially less than the density of the fluid 102. In the embodiment shown in FIGS. 2 and 3, two internal chambers 146 are shown, but fewer or more internal chambers 146 may be used to allow the valve 140 to float relative to the pump unit 106. It should be understood that. The valve 140 may be composed of two or more parts secured together around the pump unit 106, or the valve 140 may be configured as an integrated unit. For example, check valve 142 may be removably coupled to housing 126 (not shown) to follow the arrangement of valve 140 around pump unit 106. However, it should be understood that other suitable assembly methods may be used to position the valve 140 with respect to the pump unit 106.
[0032]
In the embodiment shown in FIGS. 2 and 3, the housing 126 includes an upper stop 150 and a lower stop 152 integrally formed. Stops 150 and 152 limit upward and downward movement of valve 140 to a predetermined position relative to pump unit 106 in response to changes in the level of fluid 102 in well bore 104. For example, as shown in FIG. 2, as the level of fluid 102 in well hole 104 increases, valve 140 floats upward with respect to pump unit 106 until upper end 154 of valve 140 reaches stop 150. Similarly, referring to FIG. 3, as the level of fluid 102 in well hole 104 decreases, valve 140 floats with respect to pump unit 106 until lower end 156 of valve 140 reaches stop 152. . Accordingly, as described in more detail below, stops 150 and 152 are provided on pump unit 106 to position valve 140 in position relative to pump unit 106 to facilitate circulation of fluid 102 to be pumped. Be placed.
[0033]
As shown in FIGS. 2 and 3, the valve 140 includes a passage 160 extending from an upper end 162 of the valve 140 to a lower end 164 of the valve 140. Passage 160 allows all or a portion of fluid 102 to be pumped in response to a decrease in fluid 102 level in well hole 104 from discharge end 122 of stator / rotor portion 110 to stator / rotor portion. A communication path is provided for circulation to an inlet 118 of 110. The circulation of the pumped fluid 102 will be described in detail below with reference to FIG.
[0034]
The system 100 also includes a locking system 170 that releasably secures the valve 140 to each predetermined position with respect to the pump unit 106. In this embodiment, locking system 170 includes a locking element 172 biased inwardly against valve 120 toward housing 126 via spring 174. Housing 126 includes integrally formed recesses 176 and 178 configured to receive locking element 172 to releasably secure valve 140 in predetermined positions relative to pump unit 106. For example, as shown in FIG. 2, in response to an increase in the level of fluid 102 in well hole 104, valve 140 causes pump unit 106 to move upward to a position where locking system 170 releasably secures valve 140. Floating upwards. As will be described in more detail below, the locking system 170 substantially prevents unwanted movement of the valve 140 relative to the pump unit 106 as a result of turbulence or small changes in the fluid 102 in the well hole 104. To prevent. The locking system 170 also provides a mechanism to lock the valve 140 in place with respect to the pump unit 106 to substantially reduce the force required to operate the pump unit 106.
[0035]
As shown in FIG. 3, as the level of fluid 102 in well hole 104 decreases, valve 140 moves to a downwardly moved position where the locking system releasably secures valve 140. The locking system 170 may be configured such that the weight of the valve 140, which is not supported by the fluid 102, is greater than the force of the inward spring 174, thereby moving upward in response to a decrease in the level of the fluid 102 in the well hole 104. This causes release of valve 140 from the position. Thus, as will be described in greater detail below, the locking system 170 may operate the valve 140 with respect to the pump unit 106 to facilitate the circulation of the pumped fluid 102 or to stop the circulation of the pumped fluid 102. And releasably fixed in position.
[0036]
As shown in FIGS. 2 and 3, the pump unit 106 includes a port 190 formed in the wall 192 of the housing 126 near the discharge end 122 of the stator / rotor portion 110. Pump unit 106 also includes a port 194 formed in wall 192 of housing 126 near inlet 118 of stator / rotor portion 110. Seals 198, such as O-ring elastomeric seals or other suitable sealing members, are located on both sides of ports 190 and 194 to prevent unwanted leakage of fluid 102 around ports 190 and 194 to valve 140.
[0037]
The non-return valve 142 includes a ball or sphere 200 sized larger than the dimension of the inlet 204 of the non-return valve 142 disposed within the interior region 202 of the non-return valve 142, and the sphere 200 is moved from the interior region 202 to the entrance 204 May be received by seat area 206 of check valve 142 to substantially prevent passage of fluid 102 therethrough. However, it should be understood that any other suitable shape, such as an oval, or a device, such as a flapper, may be used to substantially prevent the passage of the fluid 102 from the interior region 202 through the inlet 204. As will be described in more detail below, a check valve 142 is located near the inlet 118 of the stator / rotor portion 110 of the pump unit 106 to direct the circulated fluid 102 to the inlet 118.
[0038]
In operation, the generally high or elevated level of fluid 102 in well hole 104 causes valve 140 to move upward relative to pump unit 106, as shown in FIG. The locking system 170 releasably locks the valve 140 in the upwardly-moved position such that the passage 160 of the valve 140 does not coincide with the ports 190 and 194 so that the fluid 102 can be removed from the outlet 120 of the stator / rotor portion 110. Prevent release. Thus, in operation, rotation of rotor 112 relative to stator 116 draws fluid 102 inwardly through inlet 204 of check valve 142 and into interior region 202 of check valve 142. Fluid 102 is further drawn into inlet 118 of stator / rotor section 110 and discharged from outlet 120 as described above. In the upwardly-moved position, the passage 160 of the valve 140 is not aligned with the port 190, thus allowing the pumped fluid 102 to travel upwardly to the surface via the annulus 124. The locking system 170 releasably secures the valve 140 in the upwardly moved position to prevent unwanted movement of the valve 140 in response to small fluctuations or disturbances in the level of the fluid 120 within the wellbore 104. In addition, stop 150 prevents further upward movement of valve 140 and accommodates engagement of locking system 170.
[0039]
When the level of fluid 102 in wellbore 104 decreases, valve 140 moves pump unit 106 to a position where locking system 170 releasably secures portion 140 in the down-moved position, as shown in FIG. Proceed downward. In the position of the valve 140 shown in FIG. 3, the inlet 208 of the passage 160 is aligned with the port 190, and thus all or a portion of the pumped fluid 102 from the discharge end 122 of the stator / rotor portion 110 to the passage 160. Receive some. In addition, at the position of the valve 140 moved downward as shown in FIG. 3, the outlet 210 of the passage 160 is aligned with the port 194, thus communicating fluid in the passage 160 to the interior area 202 and the inlet 118 of the check valve 142. Let it.
[0040]
As shown in FIG. 3, the decrease in the flow rate of the upward fluid 102 to the surface causes the sphere 200 to move downward and seat against the seat area 206 of the check valve 142, thereby passing through the port 194. Substantially preventing the received circulated fluid 102 from exiting the inlet 204. Accordingly, the locking system 170 may be moved to the open or closed position to enable or disable circulation of the fluid 102, respectively, and to substantially reduce or eliminate adjustment of the valve 140 with respect to the pump unit 106. Provides a secure arrangement of the valve 140. In addition, the locking system 170 releasably locks the valve 140 in the fully open position, thereby causing circulation of the fluid 102, thereby, for example, the pump unit 106, such as the power required to rotate the rotor 112. To substantially reduce the power required to operate.
[0041]
Thus, in response to a decrease in the level of fluid 102 in well hole 104, valve 140 causes all or a portion of pumped fluid 102 from discharge end 122 of stator / rotor portion 110 to move to stator / rotor. Valve 140 moves downward relative to pump unit 106 to circulate back to inlet 118 of rotor portion 110, thereby substantially preventing pump unit 106 from operating in a "dry", unlubricated condition. As such, it provides a continuous loop of the fluid 102 to the inlet 118. The passage 160 of the valve 140 provides a fluid communication path between the discharge end 122 and the inlet 118 in the downwardly-moved position shown in FIG. 3 so that, in response to a decrease in the level of the fluid 102 in the well hole 104, Circulated pumped fluid 102 to the inlet of stator / rotor section 110. Passage 160 and ports 190 and 194 may be sized to circulate all or a portion of fluid 102.
[0042]
Similarly, as the level of fluid 102 in well hole 104 increases, valve 140 advances upward relative to pump unit 102 to the position shown in FIG. As described above, the locking system 170 causes the rising level of the fluid 102 in the well bore 104 to produce an upward force on the valve 140 that is greater than the normal inward force from the spring 174, which causes the valve 140 to Removed from the position where it moved downward. As valve 140 moves upward or floats with respect to pump unit 106, passage 160 will no longer match ports 190 and 194, thereby stopping circulation of fluid 102 to inlet 118. Seal 189 substantially prevents any unwanted flow of fluid 102 through ports 190 and 194. Thus, the upward movement of valve 140 relative to pump unit 106 causes pumped fluid 102 to be redirected upward to the surface.
[0043]
Thus, the present invention provides a fluid level controlled pump system that automatically circulates the pumped fluid 102 to the inlet 118 of the pump unit 106 in response to changes in the level of the fluid 102 in the well hole 104. I do. Thus, the present invention provides higher reliability than prior art pump systems by maintaining the lubrication status of the pumping device while the fluid level in the wellbore drops, thereby extending the life of the pumping device. Further, the present invention operates independently of manual intervention by an operator or user, and is therefore more reliable and easier to use.
[0044]
FIG. 4 is a flowchart illustrating a fluid level controlled pump method according to an embodiment of the present invention. The method starts at step 200 where the pump unit 12 is placed in the wellbore 16. As described above, pump unit 12 may include a progressive cavity pump 18 or other suitable type of pump unit. In step 202, pressure source 72 is used to push a controlled volume of fluid downwardly through passageway 60 into the wellbore. As mentioned above, in the progressive cavity pump 18 shown in FIG. 1, the pressurized fluid is forced downward through the rotor 30 through the passage 60. However, passage 60 may otherwise be located or configured relative to pump unit 12 such that end 62 of passage 60 is located near suction end 34 of pump unit 12.
[0045]
In step 204, the pressurized fluid is expelled outwardly from end 62 of passage 60 near suction end 34 of pump unit 12. In step 206, controller 76 monitors the pressure in passage 60 via a signal received from sensor 74. As described above, sensor 74 is coupled to passage 60 and measures the fluid pressure in passage 60 corresponding to depth 64 of fluid 32 in wellbore 16. At step 208, the controller 76 determines whether a change in pressure has occurred in the passage 60 and indicates a variation in the level of the fluid 32 in the wellbore 16. The controller 76 processes the command such that the variation in the pressure in the passageway 60 must exceed a predetermined amount before the corresponding variation in the level of the fluid 32 guarantees a change in the operating parameters of the pump unit 12. And / or programming. However, alternatively, the controller 76 may be configured to automatically adjust the operating parameters of the pump unit 12 based on fluctuations in the pressure in the passage 16.
[0046]
In decision step 210, it is determined whether the pressure in passage 60 has increased. If the pressure in passage 60 increases, the method proceeds from step 210 to step 212 where controller 76 begins increasing the flow rate of fluid 32 through pump unit 12. As described above, the controller 76 sends control signals to the drive motor 78 to adjust the operating parameters of the pump unit 12 to increase the pump flow rate. If no pressure increase has occurred, the method proceeds from step 210 to step 214.
[0047]
At decision step 214, it is determined whether the pressure in passage 60 has decreased. If the pressure in passage 60 decreases, the method proceeds from step 216 to step 218 where controller 76 begins to reduce the flow rate of fluid 32 through pump unit 12. As described above, controller 76 sends a control signal to drive motor 78 to reduce the pump flow rate of fluid 32 pumped to surface 14. If a decrease in pressure in passage 60 has not occurred, the method proceeds from step 216 to step 220 where it is determined whether further monitoring of the pressure in passage 60 is required. If further pressure monitoring is required, the method returns to step 206. If no further monitoring is required, the method is complete.
[0048]
Thus, the present invention provides an efficient fluid controlled to substantially prevent the pump unit from operating in "dry" or non-lubricated situations, thereby extending the operating life of the pump unit. Provide a pump system. The present invention also provides a fluid level controlled pump system that requires minimal manual operation and monitoring, thereby increasing the efficiency of the pump operation.
[0049]
Although the present invention has been described in detail, various changes and modifications may be suggested to one skilled in the art. The present invention is intended to cover such changes and modifications that fall within the scope of the appended claims.
[Brief description of the drawings]
[0050]
FIG. 1 illustrates a fluid controlled pump system according to one embodiment of the present invention.
FIG. 2 illustrates a fluid controlled pump system according to another embodiment of the present invention.
3 illustrates the fluid controlled pump system shown in FIG. 2 after a change in fluid level in the fluid cavity according to one embodiment of the present invention.
FIG. 4 is a flowchart illustrating a method of fluid-level controlled pumping according to one embodiment of the present invention.

Claims (92)

A pump unit disposed within the fluid cavity and having a passage extending to a suction end of the pump unit;
A pressure source coupled to the passage and operable to push fluid outwardly from the passage near the suction end of the pump unit;
A pressure sensor coupled to the passage and operable to measure fluid pressure in the passage;
A controller coupled to the pump unit and operable to adjust an operating parameter of the pump unit using the fluid pressure.
Fluid controlled pump system. The system of claim 1, wherein the pump unit comprises a progressive cavity pump. The system of claim 2, wherein the operating parameter comprises a rotational speed of the progressive cavity pump. The system of claim 1, wherein the fluid pressure in the passage corresponds to a fluid depth in the fluid cavity. The pump unit includes:
A stator,
A rotor disposed inside the stator and operable to rotate relative to the stator to pump fluid in the fluid cavity from a first position to a second position;
The system of claim 1, wherein the passage comprises an interior passage of the rotor. The system of claim 1, wherein the pressure source comprises a pneumatic pressure source. The system of claim 1, wherein the pressure source comprises compressed nitrogen. The system of claim 1, wherein the operating parameter comprises a flow rate of the pump unit, and wherein the controller is operable to reduce the flow rate in response to a decrease in the fluid pressure. The system of claim 1, wherein the operating parameter comprises a flow rate of the pump unit, and wherein the controller is operable to increase the flow rate in response to an increase in the fluid pressure. The system of claim 1, wherein the controller is operable to adjust the operating parameters of the pump unit to maintain a substantially constant depth of fluid in the fluid cavity. Providing a pump unit having a passage disposed within the fluid cavity and extending to a suction end of the pump unit;
Forcing fluid outwardly from the passage near the suction end of the pump unit;
Measuring a fluid pressure in the passage;
Automatically adjusting operating parameters of the pump unit using the fluid pressure.
Fluid controlled pumping method. 12. The method of claim 11, wherein providing the pump unit comprises providing a progressive cavity pump. 13. The method of claim 12, wherein adjusting the operating parameter comprises adjusting a rotational speed of the progressive cavity pump. The method of claim 11, wherein measuring the fluid pressure in the passage includes measuring a fluid depth in the fluid cavity. Providing the pump unit includes providing a progressive cavity pump, wherein the progressive cavity pump includes a stator and a rotor, wherein the rotor is disposed inside the stator and includes the fluid cavity. The rotor is operable to rotate relative to the stator to pump fluid therein from a first position to a second position, the passage including an interior passage of the rotor. 12. The method according to 11. The method of claim 11, wherein pushing the fluid comprises pushing compressed air outward from the passage. The method of claim 11, wherein extruding the fluid comprises extruding compressed nitrogen outward from the passage. The method of claim 11, wherein adjusting the operating parameter comprises reducing a flow rate of the pump unit in response to a decrease in the fluid pressure. 12. The method of claim 11, wherein adjusting the operating parameter comprises increasing a flow rate of the pump unit in response to increasing the fluid pressure. The method of claim 11, wherein adjusting the operating parameter comprises adjusting a flow rate of the pump unit to maintain a substantially constant fluid level in the fluid cavity. A progressive cavity pump having a stator disposed within the fluid cavity and having a rotor having an internal passage extending to a suction end of the pump;
A pressure source coupled to the passage and operable to push fluid downwardly from the passage near the suction end of the pump;
A pressure sensor operable to measure a fluid pressure in the passage;
A controller operable to adjust a rotational speed of the rotor using the fluid pressure in the passage.
Fluid level controlled pump system. 22. The system of claim 21, wherein the controller is further operable to adjust a rotational speed of the rotor to maintain a substantially constant fluid level within the fluid cavity. 22. The system of claim 21, wherein the controller is operable to increase a rotational speed of the rotor in response to the increase in the fluid pressure. 22. The system of claim 21, wherein the controller is operable to reduce a rotational speed of the rotor in response to a decrease in the fluid pressure. 22. The system of claim 21, wherein the pressure source comprises a pneumatic pressure source. Further comprising a motor coupled to the pump and operable to impart a rotational force to the rotor, wherein the controller is operable to send a control signal to the motor to adjust the rotational force. Item 23. The system according to Item 21. 22. The controller of claim 21, wherein the controller is further operable to adjust the rotational speed of the rotor to substantially prevent the rotor from rotating without fluid lubrication within the fluid cavity. System. Providing a progressive cavity pump having a stator disposed within the fluid cavity and having a rotor having an internal passage extending to a suction end of the pump;
Forcing fluid downwardly outwardly from the passage near the suction end of the pump, downwardly through the passage;
Measuring a fluid pressure in the passage;
Automatically adjusting the rotational speed of the rotor using the fluid pressure in the passage.
Fluid level controlled pumping method. 29. The method of claim 28, wherein adjusting comprises adjusting the rotational speed of the rotor to maintain a substantially constant fluid level within the fluid cavity. 29. The method of claim 28, wherein said adjusting comprises increasing a rotational speed of said rotor in response to said fluid pressure increasing. 29. The method of claim 28, wherein the adjusting comprises reducing a rotational speed of the rotor in response to a decrease in the fluid pressure. 29. The method of claim 28, wherein pushing the fluid downward comprises pushing compressed air downward through the passage. 29. The method of claim 28, further comprising providing a rotational force to the rotor using a motor, wherein the adjusting comprises transmitting a control signal to the motor to adjust the rotational force. 29. The method of claim 28, wherein the adjusting comprises adjusting a rotational speed of the rotor to substantially prevent the rotor from rotating without fluid lubrication within the fluid cavity. Providing a pump unit in the cavity having a suction end operable to draw the cavity fluid into the pump unit to transfer the cavity fluid from the first position to the second position;
Measuring a pressure corresponding to a depth of the cavity fluid in the cavity, near the suction end of the pump unit;
Automatically adjusting the flow rate of the hollow fluid through the pump unit using the measured pressure.
Fluid level controlled pumping method. The step of arranging the pump unit includes the step of arranging a progressive cavity pump, and the adjusting step adjusts a rotation speed of a rotor of the progressive cavity pump using the measured pressure. 36. The method of claim 35, comprising a step. Measuring the pressure comprises:
Forcing a controlled volume of fluid outwardly from a passage having an outlet near the suction end of the pump unit;
Measuring the pressure in the passage. 38. The method of claim 37, wherein extruding a controlled volume of the fluid comprises extruding a controlled volume of the fluid downwardly within an interior passage of the rotor. The step of adjusting the flow rate comprises:
Receiving a first signal from a pressure sensor indicating the pressure;
Transmitting a second signal to a drive motor coupled to the pump unit and operable to control a flow rate of the pump unit. Providing the pump unit includes providing a progressive cavity pump, and transmitting the second signal comprises transmitting the second signal to the drive motor to control a rotational speed of a rotor of the progressive cavity pump. 40. The method of claim 39, comprising transmitting a second signal. A progressive cavity pump having a stator disposed within the fluid cavity and having a rotor having an internal passage extending to a suction end of the pump;
A pressure source coupled to the passage and operable to push fluid downwardly from the passage near the suction end of the pump;
A sensor operable to measure a fluid pressure in the passage indicative of a fluid level in the fluid cavity.
Pump system. 42. A controller coupled to the rotor and further comprising a controller operable to adjust a rotational speed of the rotor to maintain a substantially constant fluid level within the fluid cavity using the fluid pressure. The described system. 42. The system of claim 41, further comprising a controller coupled to the rotor and operable to increase a rotational speed of the rotor in response to the increase in the fluid pressure. 42. The system of claim 41, further comprising a controller coupled to the rotor and operable to reduce a rotational speed of the rotor in response to a decrease in the fluid pressure. A motor coupled to the rotor and operable to impart rotational force to the rotor;
42. The system of claim 41, further comprising: a controller operable to send a control signal to the rotor to adjust the rotational force based on the fluid pressure. 42. The system of claim 41, wherein the pressure source comprises a pneumatic pressure source. A pump unit disposed within the fluid cavity and having an inlet operable to receive fluid to be pumped from the fluid cavity;
A valve slidably coupled to the pump unit and having a passage for receiving fluid pumped from an outlet of the pump unit;
In response to a decrease in the fluid level in the fluid cavity, movement of the valve relative to the pump unit adjusts the passage to a port of the pump unit to circulate the pumped fluid from the outlet to the inlet.
Fluid level controlled pump system. 48. The system of claim 47, wherein said pump unit comprises a progressive cavity pump. 48. The system of claim 47, wherein the valve includes an interior chamber, wherein the interior chamber is filled with a fluid having a density less than a density of the fluid in the fluid cavity. 48. The system of claim 47, wherein said valve comprises a floating valve. 48. The system of claim 47, further comprising a locking system operable to releasably secure the valve in place with respect to the pump unit. The locking system comprises:
A locking element disposed on the valve;
A recess disposed on said pump unit configured to receive said locking element. 48. The system of claim 47, further comprising a non-return valve located near the inlet, wherein the non-return valve is operable to direct the circulated fluid to the inlet. 54. The system of claim 53, wherein the check valve is further operable to substantially prevent the circulated fluid from bypassing the inlet. 48. The system of claim 47, further comprising a plurality of stops located near the valve, wherein the stops are operable to limit movement of the valve to a predetermined position relative to the pump unit. A lower stop disposed near the valve and operable to limit downward movement of the valve to a first predetermined position relative to the pump unit;
48. The system of claim 47, further comprising an upper stop located near the valve and operable to limit upward movement of the valve to a second predetermined position relative to the pump unit. 57. The system of claim 56, wherein the lower stop is positioned to align the valve passage with a port of the pump unit in response to a decrease in fluid in the fluid cavity. A stator / rotor portion disposed within the fluid cavity for pumping fluid in the fluid cavity from a first position to a second position, the stator / rotor portion having an inlet and an outlet; A progressive cavity pump,
A valve slidably coupled to the pump;
In response to a decrease in the fluid level in the fluid cavity, movement of the valve relative to the pump causes the valve passage to align with the pump port to circulate the fluid from the outlet to the inlet.
Fluid level controlled pump system. 59. The system of claim 58, wherein the valve includes an interior chamber filled with a fluid having a density less than a density of the fluid in the fluid cavity. 59. The system of claim 58, wherein said valve comprises a floating valve. 59. The system of claim 58, further comprising a locking system operable to releasably lock the valve in place with respect to the pump. The locking system comprises:
A locking element,
A recess configured to receive the locking element and disposed on the pump unit;
63. The system of claim 61, further comprising a spring operable to bias the locking element toward the recess. 59. The system of claim 58, further comprising a check valve located near the inlet and operable to direct the circulated fluid to the inlet. 64. The system of claim 63, wherein the check valve is further operable to substantially prevent the circulated fluid from bypassing the inlet. 59. The system of claim 58, further comprising a number of stops located near the valve, wherein the stops restrict movement of the valve to a predetermined position relative to the pump. A lower stop disposed near the valve and operable to limit downward movement of the valve to a first predetermined position relative to the pump;
59. The system of claim 58, further comprising an upper stop located near the valve and operable to limit upward movement of the valve to a second predetermined position relative to the pump. 67. The system of claim 66, wherein the lower stop is positioned to align the valve passage with a port of the pump in response to a decrease in fluid in the fluid cavity. A locking element disposed biased inward from the valve toward the pump;
A plurality of recesses disposed on the pump and configured to receive the locking element;
59. The system of claim 58, wherein the recess is positioned on the pump to releasably secure the valve in place with respect to the pump. 69. The system of claim 68, wherein one of the recesses is arranged to releasably secure the valve to the pump to align the passage with the port. A stator / rotor portion disposed within the fluid cavity for pumping fluid in the fluid cavity from a first position to a second position, the stator / rotor portion having an inlet and an outlet; A progressive cavity pump,
A valve slidably coupled to the pump and operable to adjust a passage of the valve to a port of the pump in response to a change in fluid level in the fluid cavity;
A fluid level controlled pump system, wherein the passage is operable to direct the fluid from the outlet to the inlet to substantially prevent a lack of fluid at the inlet. 71. The check valve further comprising a non-return valve positioned near the inlet, the non-return valve operable to substantially prevent fluid received from the passage from bypassing the inlet. System. 71. The system of claim 70, wherein said valve comprises a floating valve. 71. The system of claim 70, wherein changing the level of the fluid comprises decreasing the level of the fluid. 71. The system of claim 70, wherein the valve includes an interior chamber, wherein the interior chamber is filled with a fluid having a lower density than the fluid in the fluid cavity. 71. The system of claim 70, further comprising a locking system operable to releasably lock the valve in place with respect to the pump. The locking system comprises:
A locking element disposed biased inward from the valve toward the pump;
A plurality of recesses disposed on the pump and configured to receive the locking element;
76. The system of claim 75, wherein the recess is positioned on the pump to releasably secure the valve in place with respect to the pump. A lower stop disposed near the valve and operable to limit downward movement of the valve to a first predetermined position relative to the pump unit;
71. The system of claim 70, further comprising an upper stop located near the valve and operable to limit upward movement of the valve to a second predetermined position relative to the pump unit. 78. The system of claim 77, wherein the lower stop is positioned to align a passage of the valve with a port of the pump unit in response to downward movement of the valve relative to the pump. 78. The system of claim 77, wherein the upper stop is positioned to substantially prevent the fluid from entering the passage in response to upward movement of the valve relative to the pump. A progressive cavity pump disposed within the fluid cavity and having a stator / rotor portion for pumping fluid within the fluid cavity, the stator / rotor portion having an inlet and an outlet;
A valve coupled to the pump and disposed in communication with the outlet, the valve being operable to circulate the fluid from the outlet to the inlet in response to a decrease in fluid level in the fluid cavity. Pump system. 81. The system of claim 80, further comprising a non-return valve positioned near the inlet, the non-return valve operable to substantially prevent the circulated fluid from bypassing the inlet. . The valve includes a floating valve, the floating valve being operable to match a port of the pump located near the outlet with a passage of the valve in response to a decrease in the fluid level, the passage being circulated to the circulation of the valve. 81. The system of claim 80, operable to direct fluid to be directed to the inlet. 83. The system of claim 82, wherein the floating valve includes an interior chamber, the interior chamber being filled with a fluid having a lower density than the density of the fluid in the fluid cavity. The valve further includes a plurality of stops slidably coupled to the pump and positioned near the valve, the stops operative to limit movement of the valve to a predetermined position relative to the pump unit. 81. The system of claim 80, wherein the system is capable. The plurality of stoppers,
An upper stop operable to limit upward movement of the valve in response to an increase in the fluid level within the fluid cavity to a first predetermined position relative to the pump;
85. The system of claim 84, further comprising a lower stop operable to limit downward movement of the valve in response to a decrease in the fluid level within the fluid cavity to a second predetermined position relative to the pump. Providing a progressive cavity pump disposed within a fluid cavity and having a stator / rotor portion for pumping fluid located within the fluid cavity, the stator / rotor portion having an inlet and an outlet. Stages and
Providing a valve coupled to the pump and operable to receive the fluid from the stator / rotor portion;
Circulating said fluid from said outlet to said inlet via said valve in response to a decrease in fluid level in said fluid cavity.
Fluid level controlled pumping method. 87. The method of claim 86, wherein said circulating further comprises matching a passage of said valve to a port of said pump, said port being located near said outlet. 89. The method of claim 86, wherein providing the valve comprises providing a floating valve, the floating valve being operable to move relative to the pump in response to a change in the fluid level in the fluid cavity. Method. 89. The method of claim 88, further comprising providing a plurality of stops located near the valve, wherein the stops are operable to limit movement of the valve to a predetermined position relative to the pump. The step of providing the plurality of stops includes:
Providing a first stop operable to limit upward movement of the valve in response to an increase in the fluid level in the fluid cavity to a first predetermined position relative to the pump;
Providing a second stop operable to limit downward movement of the valve in response to a decrease in the fluid level in the fluid cavity to a second predetermined position relative to the pump. The described method. 87. The method of claim 86, wherein said circulating step includes circulating said fluid to substantially prevent operation of said pump without fluid lubrication within said fluid cavity. Providing the valve includes providing a valve slidably coupled to the pump, and providing a locking system operable to releasably lock the valve in place relative to the pump. 87. The method of claim 86, further comprising:

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