US20070196229A1 - Gear pump for pumping abrasive well fluid - Google Patents

Gear pump for pumping abrasive well fluid Download PDF

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Publication number
US20070196229A1
US20070196229A1 US11/358,192 US35819206A US2007196229A1 US 20070196229 A1 US20070196229 A1 US 20070196229A1 US 35819206 A US35819206 A US 35819206A US 2007196229 A1 US2007196229 A1 US 2007196229A1
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US
United States
Prior art keywords
drive
lobes
driven
well
members
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US11/358,192
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English (en)
Inventor
Farral Gay
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Baker Hughes Holdings LLC
Original Assignee
Baker Hughes Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Baker Hughes Inc filed Critical Baker Hughes Inc
Priority to US11/358,192 priority Critical patent/US20070196229A1/en
Assigned to BAKER HUGHES INCORPROATED reassignment BAKER HUGHES INCORPROATED ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: GAY, FARRAL D.
Priority to CA002647191A priority patent/CA2647191A1/fr
Priority to PCT/US2007/004395 priority patent/WO2007136438A1/fr
Publication of US20070196229A1 publication Critical patent/US20070196229A1/en
Abandoned legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C2/00—Rotary-piston machines or pumps
    • F04C2/08—Rotary-piston machines or pumps of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing
    • F04C2/082—Details specially related to intermeshing engagement type machines or pumps
    • F04C2/084—Toothed wheels
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C13/00—Adaptations of machines or pumps for special use, e.g. for extremely high pressures
    • F04C13/008—Pumps for submersible use, i.e. down-hole pumping
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C2230/00—Manufacture
    • F04C2230/90—Improving properties of machine parts
    • F04C2230/91—Coating

Definitions

  • This invention relates in general to well pumps, and in particular to a low volume positive displacement pump for pumping abrasive well fluid.
  • Centrifugal pumps are commonly used in oil well production for producing large volumes of fluid.
  • a centrifugal pump assembly comprises a downhole electrical motor, a pump made up of a plurality of stages, each stage having an impeller and diffuser, and a seal section located between the motor and pump.
  • the seal section equalizes the pressure of lubricant within the motor with the hydrostatic pressure of well fluid on the exterior. If the well produces a significant amount of sand, to reduce wear, some of the thrust and radial bearings in the stages can be formed of a hard, wear resistant material, such as tungsten carbide.
  • Some wells require only fairly low flow rate pumps. For example, dewatering coal bed methane wells can be done with a small centrifugal pump but small centrifugal pumps are not particularly efficient. Also, if the well fluid contains abrasive particles, providing centrifugal well pumps with hard, wear-resistant components to resist the abrasive wear is expensive.
  • a positive displacement pump is utilized for low volume wells having abrasive fluid.
  • the positive displacement pump is preferably of a type having a driven member with lobes that intermesh with lobes of a drive member, such as a gear pump.
  • An electric motor rotates the drive member, causing well fluid on an intake side to flow between the lobes of the drive and driven members to a discharge side.
  • the intake leads to the exterior of the pump and is submersed in the well fluid.
  • the discharge is connected to a conduit leading to the surface of the well.
  • one of the members has lobes or teeth formed of a hard, wear-resistant metal.
  • the other member has lobes or teeth formed of an elastomeric material.
  • the elastomeric material deflects when contacted by abrasives in the well fluid, reducing wear on the metal teeth.
  • the drive and driven members comprise gear teeth.
  • the drive and driven members are located within a cavity of a plate of a uniform thickness.
  • the plate is sandwiched between a motor housing and a manifold housing.
  • the thickness of the plate is the same as the thickness or axial dimension of each of the drive and driven members.
  • the flow rate can be changed by increasing the dimension of the drive and driven members.
  • the plate can be readily interchanged with a plate having a thickness to match the thickness of any drive and driven members selected.
  • the motor and manifold are interchangeable with different thicknesses of plates.
  • FIG. 1 is schematic sectional view illustrating a gear pump constructed in accordance with this invention installed within a well.
  • FIG. 2 is an enlarged vertical sectional view of the gear pump of FIG. 1 , taken along the line 2 - 2 of FIG. 4 .
  • FIG. 4 is a sectional view of the gear pump of FIG. 1 , taken along the line 4 - 4 of FIG. 2 .
  • Well 11 is of a type that that requires pumping at a fairly low flow rate and may contain abrasive material within the well fluid.
  • well 11 may be a coal bed methane well that requires dewatering.
  • a string of conduit or tubing 13 is shown suspended within casing 11 .
  • a positive displacement pump assembly preferably a gear pump 15 , is suspended from the lower end of tubing 13 .
  • Gear pump assembly 15 has an intake 17 submersed within the well fluid for pumping the well fluid up tubing 13 to the surface.
  • pump assembly 15 includes a submersible electrical motor 19 .
  • Electrical motor 19 is located within a motor housing 21 that is sealed from the well fluid, and forms part of the housing assembly of pump assembly 15 .
  • Motor housing 21 has a bottom 21 a, a top 21 b, and a cylindrical sidewall 21 c.
  • Motor 19 may be of a variety of types but is preferably an AC motor with a stator 23 having a central opening for receiving a rotor 25 .
  • Rotor 25 causes a drive shaft 27 to rotate when stator 23 is energized. Electrical power is supplied to motor 19 by a power cable (not shown) that extends downward from the surface.
  • Drive shaft 27 is supported by a lower bearing 29 on motor housing bottom 21 a and a radial bushing within a depending tubular portion of top 21 b. In this embodiment, drive shaft 27 is located on the axis of motor housing 21 .
  • the housing assembly for pump assembly 15 also includes a pump base plate 33 , which is mounted on motor housing top 21 b.
  • Pump base plate 33 is preferably a solid, metal plate such as stainless steel, that has been hardened and is resistant to wear where exposed to the abrasive fluid well.
  • Plate 33 has a flat lower side and a flat upper side, the sides being parallel to each other to define a uniform thickness for plate 33 .
  • Plate 33 is separated from housing top 21 b in this embodiment by a gasket 34 to prevent leakage.
  • plate 33 has a closed cavity formed within it, the cavity having an intake portion 35 , a discharge portion 37 , a drive gear portion 39 and a driven gear portion 41 .
  • Portions 35 , 37 , 39 and 41 join each other to form general cross shape with rounded ends.
  • intake cavity portion 35 and discharge cavity portion 37 are semi-circular.
  • drive gear cavity portion 39 and driven gear cavity portion 41 are semi-circular.
  • a drive gear 43 is rotatably mounted within drive gear cavity 39 .
  • Drive gear 43 is a gear member that has a plurality of lobes or teeth 45 spaced around its circumference.
  • Drive gear 43 is preferably formed of a hard wear-resistant metal, such as stainless steel.
  • Drive gear 43 is rigidly secured to drive shaft 27 by a key for rotation therewith.
  • a driven gear 47 is located adjacent drive gear 43 .
  • Driven gear 47 also has a plurality of lobes or teeth 49 spaced around its periphery. Teeth 45 intermesh with teeth 49 so that rotation of drive gear 43 causes driven gear 47 to rotate.
  • Driven gear 47 is rigidly mounted to a driven shaft 51 that is free to rotate. As shown in FIG. 3 , driven shaft 51 has a lower end that rotatably fits within a receptacle 53 containing a bushing 55 . Bushing 55 seals drive shaft 27 and bushing 31 seals driven shaft 51 , preventing leakage of well fluid into motor housing 21 . Driven shaft 51 is parallel to drive shaft 21 .
  • drive and driven gears 43 , 47 are identical in size, but driven gear 47 is formed of a resilient elastomeric material.
  • driven gear 47 could be formed of a hard, wear resistant metal and drive gear 43 formed of an elastomeric material.
  • both drive gear 43 and driven gear 47 could be formed of the same material, either elastomer or metal, particularly if the well fluid is not very abrasive.
  • the housing assembly for pump assembly 15 also includes a manifold housing 57 , which fits on top of pump base plate 33 and is separated by a sealing gasket 59 .
  • Manifold housing 57 has a drive shaft receptacle 61 that receives the upper end of drive shaft 27 .
  • a bushing 63 is located within receptacle 61 to serve as a radial support bearing.
  • Manifold housing 57 also has a driven shaft receptacle 65 that is adjacent and parallel to drive shaft receptacle 61 .
  • Driven shaft receptacle 65 has a bushing 67 for rotatably receiving the upper end of driven shaft 51 .
  • Bolts (not shown) extend from manifold housing 57 through base plate 33 and into threaded receptacles in motor housing 21 , clamping base plate 33 between manifold housing 57 and motor housing 21 .
  • manifold housing 57 has an intake port 69 that leads from the exterior of manifold housing 57 downward and inward into registry with intake cavity portion 35 ( FIG. 4 ).
  • Manifold housing 57 has a discharge port 71 that leads outward and is in registry with discharge cavity portion 37 ( FIG. 4 ).
  • Discharge port 71 preferably leads through an upper end 73 that contains threads or structure for securing pump assembly 15 to the lower end of tubing 13 .
  • gear 19 In operation, electrical power is supplied to motor 19 , which causes shaft 27 to rotate drive gear 43 ( FIG. 4 ).
  • Drive gear 43 rotates driven gear 47 , and the intermeshing engagement of gears 43 , 47 draws well fluid through intake port 69 into intake cavity 35 ( FIG. 4 ).
  • the rotating engagement of gears 43 , 47 forces the well fluid into discharge cavity 37 , and from there through discharge port 71 up tubing 13 .
  • Abrasive particles in the well fluid may temporarily embed in the resilient elastomeric driven gear 47 , thereby enabling the particles to pass through the pump without damage to either gear 43 or 47 .
  • the flow rate is a function of the axial dimension of drive and driven gears 43 , 47 .
  • the flow rate increases as the axial dimension or thickness of gears 43 , 47 increases.
  • stacking multiple drive gears 43 upon each other, and multiple driven gears 47 upon each other is another manner in which the thickness can be increased.
  • Electrical motor 19 would have the capacity to accommodate gears 43 , 47 of various thickness.
  • motors of smaller and larger capacity could readily bolt to pump base plate 33 .
  • Manifold housing 57 would be operable for a wide variety of flow rates.
  • Pump base plate 33 should have a thickness that matches the thickness of drive and driven gears 43 , 47 , thus it would differ depending upon the flow rate of the pump.
  • the invention has significant advantages.
  • the downhole gear pump has a higher efficiency than a small centrifugal pump for low volume production.
  • Using an elastomeric gear running against a hard metal gear reduces wear caused by abrasive particles in the well fluid.
  • Expensive hardened components are not required for abrasive well fluids.
  • the pump is modular and has components that can be readily interchanged to vary the capacity of the pump.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Rotary Pumps (AREA)
  • Details And Applications Of Rotary Liquid Pumps (AREA)
US11/358,192 2006-02-20 2006-02-20 Gear pump for pumping abrasive well fluid Abandoned US20070196229A1 (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
US11/358,192 US20070196229A1 (en) 2006-02-20 2006-02-20 Gear pump for pumping abrasive well fluid
CA002647191A CA2647191A1 (fr) 2006-02-20 2007-02-15 Pompe a engrenages pour pomper du fluide de puits abrasif
PCT/US2007/004395 WO2007136438A1 (fr) 2006-02-20 2007-02-15 Pompe à engrenages pour pomper du fluide de puits abrasif

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US11/358,192 US20070196229A1 (en) 2006-02-20 2006-02-20 Gear pump for pumping abrasive well fluid

Publications (1)

Publication Number Publication Date
US20070196229A1 true US20070196229A1 (en) 2007-08-23

Family

ID=38428361

Family Applications (1)

Application Number Title Priority Date Filing Date
US11/358,192 Abandoned US20070196229A1 (en) 2006-02-20 2006-02-20 Gear pump for pumping abrasive well fluid

Country Status (3)

Country Link
US (1) US20070196229A1 (fr)
CA (1) CA2647191A1 (fr)
WO (1) WO2007136438A1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20190072090A1 (en) * 2016-02-25 2019-03-07 Advancing Pump Technology Crop. Electric motor and rod-driven rotary gear pumps
WO2022109707A1 (fr) * 2020-11-25 2022-06-02 Advancing Pump Technology Corp. Pompe rotative à engrenages dotée d'un engrenage d'entraînement centré

Citations (26)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1593820A (en) * 1925-02-25 1926-07-27 Standard Oil Co Well-pumping apparatus
US1654329A (en) * 1924-01-17 1927-12-27 Hawley Inv S Inc Well-pumping apparatus
US1917821A (en) * 1931-10-19 1933-07-11 Clement G Branstrator Pump
US2467524A (en) * 1944-09-02 1949-04-19 Gray Marine Motor Company Rotary pump with seizure preventing means
US2530767A (en) * 1945-01-31 1950-11-21 Hamill William Wilson Gear-tooth rotary pump
US2746394A (en) * 1951-08-11 1956-05-22 Gen Motors Corp Gear pump
US2833224A (en) * 1956-03-05 1958-05-06 Owen A Meyer Rotary pumps
US2966860A (en) * 1957-04-03 1961-01-03 Lobee Pump & Machinery Co Pump for corrosive fluids
US2999466A (en) * 1959-09-23 1961-09-12 Ingersoll Rand Co Pump
US3039398A (en) * 1958-11-18 1962-06-19 Claude F Bedouet Pump for pulverulent material
US3286643A (en) * 1963-10-14 1966-11-22 Dowty Technical Dev Ltd Gear pumps and motors
US3483825A (en) * 1968-04-29 1969-12-16 Chandler Evans Inc Gear pump with abrasive resistant sealing elements
US3801241A (en) * 1973-02-08 1974-04-02 Micropump Corp Pump impeller construction
US4037663A (en) * 1971-12-17 1977-07-26 Smil Buchman Method for well exploitation
US4466785A (en) * 1982-11-18 1984-08-21 Ingersoll-Rand Company Clearance-controlling means comprising abradable layer and abrasive layer
US4682939A (en) * 1986-03-25 1987-07-28 Commercial Shearing, Inc. Gear pump or motor with tooth tips of dissimilar metal
US4718824A (en) * 1983-09-12 1988-01-12 Institut Francais Du Petrole Usable device, in particular for the pumping of an extremely viscous fluid and/or containing a sizeable proportion of gas, particularly for petrol production
US4744738A (en) * 1984-10-08 1988-05-17 Shimadzu Corporation Gear pump or motor with hard layer in interior casing surface
US4761124A (en) * 1985-03-15 1988-08-02 Svenska Rotor Maskiner Aktiebolag Screw-type rotary machine having at least one rotor made of a plastics material
US5060531A (en) * 1989-01-10 1991-10-29 Ishikawajima-Harima Jukogyo Kabushiki Kaisha Screw rotor
US5163824A (en) * 1990-04-23 1992-11-17 Transcience Associates Inc. Rubber-geared pump with shaftless gear
US5165881A (en) * 1991-09-16 1992-11-24 Opcon Autorotor Ab Rotor for a screw rotor machine
US5993183A (en) * 1997-09-11 1999-11-30 Hale Fire Pump Co. Gear coatings for rotary gear pumps
US6210138B1 (en) * 1999-07-08 2001-04-03 Tuthill Pump Group, A Subsidiary Of Tuthill Corporation Rotary pump apparatus and method
US6506037B1 (en) * 1999-11-17 2003-01-14 Carrier Corporation Screw machine
US6612821B1 (en) * 2000-07-14 2003-09-02 Fluid Management, Inc. Pump, in particular gear pump including ceramic gears and seal

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2085081A (en) * 1980-10-06 1982-04-21 Fluid Kinetics Inc Submersible Gear Pump for Viscous Liquids
DE4309859C2 (de) * 1993-03-26 2000-06-08 Bosch Gmbh Robert Zahnradmaschine

Patent Citations (26)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1654329A (en) * 1924-01-17 1927-12-27 Hawley Inv S Inc Well-pumping apparatus
US1593820A (en) * 1925-02-25 1926-07-27 Standard Oil Co Well-pumping apparatus
US1917821A (en) * 1931-10-19 1933-07-11 Clement G Branstrator Pump
US2467524A (en) * 1944-09-02 1949-04-19 Gray Marine Motor Company Rotary pump with seizure preventing means
US2530767A (en) * 1945-01-31 1950-11-21 Hamill William Wilson Gear-tooth rotary pump
US2746394A (en) * 1951-08-11 1956-05-22 Gen Motors Corp Gear pump
US2833224A (en) * 1956-03-05 1958-05-06 Owen A Meyer Rotary pumps
US2966860A (en) * 1957-04-03 1961-01-03 Lobee Pump & Machinery Co Pump for corrosive fluids
US3039398A (en) * 1958-11-18 1962-06-19 Claude F Bedouet Pump for pulverulent material
US2999466A (en) * 1959-09-23 1961-09-12 Ingersoll Rand Co Pump
US3286643A (en) * 1963-10-14 1966-11-22 Dowty Technical Dev Ltd Gear pumps and motors
US3483825A (en) * 1968-04-29 1969-12-16 Chandler Evans Inc Gear pump with abrasive resistant sealing elements
US4037663A (en) * 1971-12-17 1977-07-26 Smil Buchman Method for well exploitation
US3801241A (en) * 1973-02-08 1974-04-02 Micropump Corp Pump impeller construction
US4466785A (en) * 1982-11-18 1984-08-21 Ingersoll-Rand Company Clearance-controlling means comprising abradable layer and abrasive layer
US4718824A (en) * 1983-09-12 1988-01-12 Institut Francais Du Petrole Usable device, in particular for the pumping of an extremely viscous fluid and/or containing a sizeable proportion of gas, particularly for petrol production
US4744738A (en) * 1984-10-08 1988-05-17 Shimadzu Corporation Gear pump or motor with hard layer in interior casing surface
US4761124A (en) * 1985-03-15 1988-08-02 Svenska Rotor Maskiner Aktiebolag Screw-type rotary machine having at least one rotor made of a plastics material
US4682939A (en) * 1986-03-25 1987-07-28 Commercial Shearing, Inc. Gear pump or motor with tooth tips of dissimilar metal
US5060531A (en) * 1989-01-10 1991-10-29 Ishikawajima-Harima Jukogyo Kabushiki Kaisha Screw rotor
US5163824A (en) * 1990-04-23 1992-11-17 Transcience Associates Inc. Rubber-geared pump with shaftless gear
US5165881A (en) * 1991-09-16 1992-11-24 Opcon Autorotor Ab Rotor for a screw rotor machine
US5993183A (en) * 1997-09-11 1999-11-30 Hale Fire Pump Co. Gear coatings for rotary gear pumps
US6210138B1 (en) * 1999-07-08 2001-04-03 Tuthill Pump Group, A Subsidiary Of Tuthill Corporation Rotary pump apparatus and method
US6506037B1 (en) * 1999-11-17 2003-01-14 Carrier Corporation Screw machine
US6612821B1 (en) * 2000-07-14 2003-09-02 Fluid Management, Inc. Pump, in particular gear pump including ceramic gears and seal

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20190072090A1 (en) * 2016-02-25 2019-03-07 Advancing Pump Technology Crop. Electric motor and rod-driven rotary gear pumps
US11208999B2 (en) * 2016-02-25 2021-12-28 Advancing Pump Technology Corp. Electric motor and rod-driven rotary gear pumps
WO2022109707A1 (fr) * 2020-11-25 2022-06-02 Advancing Pump Technology Corp. Pompe rotative à engrenages dotée d'un engrenage d'entraînement centré
US12510071B2 (en) 2020-11-25 2025-12-30 Advancing Pump Technology Corp. Rotary gear pump with a centered drive gear

Also Published As

Publication number Publication date
CA2647191A1 (fr) 2007-11-29
WO2007136438B1 (fr) 2008-01-17
WO2007136438A1 (fr) 2007-11-29

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Legal Events

Date Code Title Description
AS Assignment

Owner name: BAKER HUGHES INCORPROATED, TEXAS

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:GAY, FARRAL D.;REEL/FRAME:017609/0248

Effective date: 20060220

STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION