Bladder pump assembly

• US 4,886,432 A
• Filed: 06/23/1988
• Issued: 12/12/1989
• Est. Priority Date: 06/23/1988
• Status: Expired due to Fees

• Current Assignee: Geraghty & Miller, Inc. (Arcadis N.V.), Engineering Enterprises, Inc.
• Original Assignee: Engineering Enterprises, Inc.
• Inventors: Kimberlin, Denver K.
• Primary Examiner(s): Croyle, Carlton R.
• Assistant Examiner(s): Blackman, Robert N.
• Application Number:
  US07/210,332
• Time in Patent Office: 537 Days
• Field of Search: 417/390, 417/395, 417/378, 417/379, 417/394, 417/401, 417/403, 417/404, 417/413, 417/478, 138/30, 166/105.1, 166/265, 166/269, 210/416.1, 210/525, 210/776, 92/89, 92/90, 92/91, 92/92
• US Class Current: 417/478
• CPC Class Codes: F04B 43/10 Pumps having fluid drive
• CPC Class Codes: F04B 47/08 the motors being actuated by fluid

Abstract

A downhole bladder pump for pumping ligher-than-water liquids. The pump includes an outer tube closed at its bottom and top, but having slots adjacent its upper end to admit the liquid to be pumped. Positioned concentrically within the outer tube is a cylindrical bladder chamber. A cylindrical bladder is mounted within the bladder chamber and registers with the internal surface of such chamber. A cyclically-operated pneumatic control system periodically delivers pressurized air to the space between the bladder and the bladder chamber to collapse the bladder and pump liquid which has flowed into the bladder. At other times during the cycle, the control system draws the bladder outwardly against the internal surface of the bladder housing by the application of vacuum. The liquid to be pumped is then forced into the bladder through a check valve subassembly positioned in the lower end of the bladder housing. This liquid is next expressed or discharged through an upper check valve system located in the upper end of the bladder housing.

Claims

1. A bladder pump assembly comprising:

an external skimmer tube having a closed bottom, and a closed upper end;

means for admitting liquid to the interior of the skimmer tube from a location near the upper end thereof;

a cylindrical bladder support chamber positioned concentrically within the external skimmer tube, and defining an annular space therewith, said bladder support chamber having a lower end spaced upwardly from the closed bottom of said skimmer tube and having an upper end, said bladder support chamber comprising a pair of semicylindrical members each having a pair of opposed, radially outwardly extending diametric flanges with the flanges on the semicylindrical members in said pair of said semicylindrical members abutting each other and secured together;

a flexible bladder lining the inner wall of at least a major portion of said support chamber and capable of flexing radially inwardly from said inner wall toward the axis of said cylindrical bladder support chamber;

a lower check valve assembly pressed into the lower end of the bladder support chamber and having the lower end of said bladder therearound and trapped between the exterior of said lower check valve assembly and the inner wall of said bladder support chamber, said lower check valve assembly functioning to open to admit liquid into said bladder from said annular space and said space between said support chamber lower end and said skimmer tube lower end when no pressure is applied to the outer side of said cylindrical flexible chamber;

an upper check valve assembly pressed into the upper end of the bladder support chamber and having the upper end of said bladder therearound and trapped between said upper check valve assembly and the inner wall of said bladder support chamber, said upper check valve assembly functioning to open to permit the discharge of liquid therethrough from the interior of said bladder when air under pressure is introduced between said bladder and said bladder support chamber;

a liquid discharge pipe connected to said upper check valve assembly for receiving liquid pumped through said upper check valve assembly from the interior of the bladder; and

a remote pneumatic pump cycle control system connected to the bladder support chamber for delivering air under pressure to the space between said bladder and said bladder support chamber, and for evacuating the space between the bladder and the bladder support chamber following the radially inward collapse of the bladder by air under pressure.

2. A bladder pump assembly as defined in claim 1 wherein pump cycle control system comprises:

a source of air under pressure;

a source of vacuum; and

a three-way control valve connected to said bladder support chamber for periodically shifting between (a) a pressuring position for delivering air under pressure from said source of air under pressure to the space between said bladder and said bladder support chamber, and (b) an evacuating position for connecting said space between said bladder and said bladder support chamber to said source of vacuum, and (c) an atmsopheric exhaust position in which air from said space between the bladder and said bladder support chamber is vented to the atmosphere.

3. A bladder pump assembly as defined in claim 2 wherein said source of vacuum is a Venturi ejector.

4. A bladder pump assembly comprising:

an external skimmer tube having a closed bottom, and a closed upper end;

means for admitting liquid to the interior of the skimmer tube from a location near the upper end thereof;

a cylindrical bladder support chamber positioned concentrically within the external skimmer tube and defining an annular space therewith, said bladder support chamber having a lower end spaced upwardly from the closed bottom of said skimmer tube and having an upper end;

a flexible bladder lining the inner wall of at least a major portion of said support chamber and capable of flexing radially inwardly from said inner wall toward the axis of said cylindrical bladder support chamber;

a lower check valve assembly pressed into the lower end of the bladder support chamber and having the lower end of said bladder therearound and trapped between the exterior of said lower check valve assembly and the inner wall of said bladder support chamber, said lower check valve assembly functioning to open to admit liquid into said bladder from said annular space and said space between said support chamber lower end and said skimmer tube lower end when no pressure is applied to the outer side of said flexible bladder;

an upper check valve assembly pressed into the upper end of the bladder support chamber and having the upper end of said bladder therearound and trapped between said upper check valve assembly and the inner wall of said bladder support chamber, said upper check valve assembly functioning to open to permit the discharge of liquid therethrough from the interior of said bladder when air under pressure is introduced between said bladder and said bladder support chamber;

a liquid discharge pipe connected to said upper check valve assembly for receiving liquid pumped through said upper check valve assembly from the interior of the bladder; and

a remote pneumatic pump cycle control system connected to the bladder support chamber for delivering air under pressure to the space between said bladder and said bladder support chamber, and for evacuating the space between the bladder and the bladder support chamber following the radially inward collapse of the bladder by air under pressure, said pump cycle control system comprising;

a source of air under pressure;

a source of vacuum; and

a three-way control valve connected to said bladder support chamber for periodically shifting between (a) a pressuring position for delivering air under pressure from said source of air under pressure to the space between said bladder and said bladder support chamber, and (b) an evacuating position for connecting said space between said bladder and said bladder support chamber to said source of vacuum, and (c) an atmospheric exhaust position in which air from said space between the bladder and said bladder support chamber is vented to the atmosphere, said pump cycle control system further comprising;

a pilot included in said three-way control valve for shifting the control valve in response to air pressure applied to the pilot;

a three-way exhaust cycle valve;

a three-way vacuum cycle valve;

a three-way pressure cycle valve; and

conduit means interconnecting said exhaust cycle valve, said vacuum cycle valve and said pressure cycle valve and the pilot of said three-way control valve.

5. A bladder pump assembly as defined in claim 4 wherein said cylindrical bladder support chamber comprises a pair of semicylindrical members each having a pair of opposed radially outwardly extending diametric flanges, with the flange pairs of said semicylindrical members abutting each other and secured together.

6. A bladder pump assembly for pumping deleterious low density liquids from a subterranean location comprising:

an external skimmer tube having a fluid intake slotted upper end portion, and a closed lower end;

a bladder support chamber having an internal wall and a lower end, the bladder support chamber positioned within the external skimmer tube and defining an annular space therebetween, the lower end of the bladder support chamber terminating a distance from the closed lower end of the external skimmer tube;

a flexible bladder supported within the bladder support chamber, the flexible bladder having an upper end, a lower end and a length substantially coextensive in length with the bladder support chamber, the flexible bladder selectively movable between an expanded first position and a collapsed second position, in the expanded first position the flexible bladder being disposed along the internal wall of the bladder support chamber, in the collapsed second position the flexible bladder being flexed radially inwardly from the inner wall of the bladder support chamber in the direction of the axis of the cylindrical bladder support chamber;

a lower check valve supported by the lower end of the flexible bladder and extending into the cavity formed between the lower end of the bladder support chamber and the lower end of the external skimmer tube, the lower check valve having an open mode and a closed mode, in the open mode of the lower check valve the flexible bladder being disposed in the first position so that fluid can be introduced into the flexible bladder, in the closed mode of the lower check valve the flexible bladder being either in transition toward the second collapsed position, or at the second collapsed position;

an upper check valve disposed in the upper end of the flexible bladder, the upper check valve having an open mode and a closed mode, in the open mode of the upper check valve the flexible bladder being disposed in the collapsed second position so that fluid can be removed from the flexible blader, and in the closed mode of the upper check valve the flexible bladder being either in transition toward the first position, or at the first position;

means operably connected to the cylindrical bladder support chamber for selectively delivering fluid under pressure to the bladder support chamber and thereby moving the flexible bladder to the second collapsed position, and for evacuating the bladder support chamber so that the flexible bladder can be moved to the first expanded position, said means for selectively delivering fluid under pressure to the bladder support chamber and for evacuating the same comprising;

at least one flow tube disposed within the annular space formed between the external skimmer tube and the bladder support chamber, one end of the flow tube openly communicating with the interior portion of the bladder support chamber;

pneumatic pump cycle control means operably connected to the flow tube for delivering air under pressure through the flow tube to the bladder support chamber and for evacuating the bladder support chamber; and

automatic timing and control means for controlling the time periods during the pumping cycles of the pneumatic pump cycle control system to evacuate the bladder support chamber so that the bladder can be filled with the liquid, and to charge the bladder support chamber when fluid is expelled from the bladder; and

wherein each of said lower and upper check valves comprises;

a check valve head having a substantially cylindrical upper portion and a frustoconical lower portion, the frustoconical lower portion positionable within and adjacent the end of the bladder, the check valve head having a central, axially extending bore extending therethrough, the portion of the bore adjacent the frustoconical lower portion being provided with threads, said check valve head having an external annular groove adapted to receive a sealing member;

a check valve seat having external threads adapted to matingly engage the threaded portion of the bore extending through the head, the check valve seat having a seat surface and a fluid passageway extending therethrough, the check valve seat further characterized as having transverse ports for permitting fluid to enter the passageway thereof;

a ball check; and

a ball check stop rod extending diametrically across the bore in the cylindrical upper portion for restricting the opening movement of the ball check as the same is removed from the seat surface when the check valve is in an open mode.

7. A bladder pump assembly as defined in claim 6 wherein the bladder support chamber comprises:

a pair of semicylindrical members each having a pair of radially outwardly extending diametric flanges with the flange pairs of the semicylindrical members abutting each other; and

means for connecting the abutting flanges of the semicylindrical members; and

wherein the bladder comprises;

a pair of opposed flexible members each having a pair of opposed outwardly extending diametric flanges at opposite sides thereof with the flange pairs of the opposed flexible members abutting flanges of the semicylindrical members of the bladder support chamber.

8. A bladder pump assembly comprising:

an external tube having a closed end and fluid inlet means formed in an upper end portion thereof for permitting liquid located adjacent the fluid inlet means to enter the external tube;

a bladder chamber positioned within the external tube so as to define a space therebetween for receiving the liquid entering the external tube, one end of the bladder chamber terminating a distance from the closed lower end of the external tube such that a cavity is formed therebetween;

a flexible bladder supported within the bladder chamber and having an upper end, a lower end and a length substantially coextensive in length with the bladder chamber;

valve means for permitting liquid to be alternately introduced into the bladder and expelled therefrom while preventing reverse flow of liquid from the bladder into the cavity when liquid is expelled, said valve means comprising;

a lower check valve assembly disposed in the lower end of the bladder chamber, the lower check valve assembly having an open mode and a closed mode, and in the open mode of the lower check valve assembly the flexible bladder being disposed in an expanded first position so that fluid can be introduced into the flexible bladder, and in the closed mode of the lower check valve assembly, the flexible bladder being in the second, collapsed position;

an upper check valve assembly disposed in the upper end of the flexible bladder, the upper check valve assembly having an open mode and a closed mode, and in the open mode of said upper check valve assembly, said flexible bladder being disposed in said collapsed second position so that fluid can be removed from the flexible bladder, and in the closed mode of said upper check valve assembly, the flexible bladder being in the expanded first position; and

means operably connected to the cylindrical bladder support chamber for selectively delivering fluid under pressure to the bladder support chamber, and thereby moving the flexible bladder to the second, collapsed position, and for evacuating the bladder support chamber so that the flexible bladder can be moved to the expanded first position, said means operably connected to the cylindrical bladder support chamber comprising;

at least one flow tube disposed within the annular space formed between the external skimmer tube and the bladder support chamber and having one end thereof openly communicating with the interior portion of the bladder support chamber for delivering fluid between the chamber and said flexible bladder;

a pneumatic pump cycle control system operably connected to said flow tube for delivering air under pressure through the flow tube to the bladder support chamber, and for evacuating the bladder support chamber; and

automatic timing and control means for controlling the time periods during the pumping cycle of the pneumatic pump cycle control system to evacuate the bladder support chamber so that the bladder can be filled with the liquid, and to charge the bladder support chamber when fluid is expelled from the bladder; and

a liquid discharge conduit connected to the upper check valve assembly for receiving liquid pumped through the upper check valve assembly from the interior of the bladder and delivering such received liquid to a remote location.

9. A bladder pump assembly comprising:

an external skimmer tube having a closed bottom, and an upper end;

means for admitting liquid to the interior of the skimmer tube from a location near the upper end thereof;

a cylindrical bladder support chamber positioned concentrically within the external skimmer tube, and defining an annular space therewith, said bladder support chamber having a lower end spaced upwardly from the closed bottom of said skimmer tube and having an upper end;

a flexible, two-part bladder positioned within said cylindrical support chamber, said two-part bladder comprising a pair of superimposed sheets of flexible material having opposite side edges secured together to form a fluid tight enclosure between said sheets, said flexible bladder being positioned relatively near to the inner wall of at least a major portion of said support chamber at one time during the operation of said bladder pump as compared to the bladder'"'"'s position at a different time during the operation of the bladder pump, and capable of flexing radially inwardly from its position relatively near to said inner wall toward the axis of said cylindrical support chamber;

a lower check valve assembly pressed into the lower end of the bladder support chamber and having the lower end of said bladder positioned therearound and sealed therearound so that said lower check valve assembly communicates with the interior of said bladder said lower check valve assembly functioning to open to admit liquid into said bladder from said annular space, and from said space between said support chamber lower end and said skimmer tube lower end when no pressure is applied to the outer side of said flexible chamber;

an upper check valve assembly pressed into the upper end of the bladder support chamber and having the upper end of said bladder extending therearound and sealed therearound, and said upper check valve assembly communicating with the interior of the bladder, said upper check valve assembly functioning to open to permit the discharge of liquid therethrough from the interior of said bladder when air under pressure is introduced between said bladder and said bladder support chamber;

a liquid discharge pipe connected to said upper check valve assembly for receiving liquid pumped through said upper check valve assembly from the interior of the bladder; and

a remote pneumatic pump cycle control system connected to the bladder support chamber for delivering air under pressure to the space between said bladder and said bladder support chamber, and for evacuating the space between the bladder and the bladder support chamber following the radially inward collapse of the bladder by air under pressure.