US3811510A

US3811510A - Well pumping method and apparatus

Info

Publication number: US3811510A
Application number: US00147870A
Authority: US
Inventors: B Woolley; J Rogers
Original assignee: Individual
Current assignee: Individual
Priority date: 1971-05-28
Filing date: 1971-05-28
Publication date: 1974-05-21
Anticipated expiration: 1991-05-21

Abstract

A method and apparatus for improving the efficiency of a well pump are disclosed. The method includes controlling the elevation at which the well fluids enter the well to thereby control the amount of each fluid, i.e., oil and water, being lifted by the well pump and further contemplates the cooling of the well fluids prior to their passage to the pump, whereby pumping efficiency is increased. This abstract is not to be construed in any way to define or limit the invention set forth below.

Description

United States Patent 1191 Rogers et al.

WELL PUMPING METHOD AND APPARATUS Inventors: Joe C. Rogers, 216 Lisa Ln.,

Palestine, Tex. 75662; Brown J. Woolley, PO. Box 1249, Kilgore, Tex. 75662 Filed: May 28, 1971 App]. No.: 147,870

US. Cl 166/302, 166/61, 166/73, 166/140, 166/217 Int. Cl... E2 lb 23/00, E2lb 33/12, E2lb 43/24 Field of Search 166/57, 61, 62, 72, 73, 166/118,123,138,140, 213, 216, 217, 302,

References Cited 1 UNITED STATES PATENTS 12/1964 Jorda ..166/256 5/1891 Heed 166/314 [111 3,811,510 [45] 'May 21,1974

2,745,497 5/1956 Dale et al. 1615/72 3,228,471 [/1966 Shook 166/302 2,914,124 11/1959 Ripley. Jr.... 166/62 2,836,248 5/1958 Covington... 166/61 2,998,069 8/1961 Stephens 166/61 Primary Examiner-Henry C. Sutherland Assistant ExaminerJack E. Ebel [5 7] ABSTRACT A method and apparatus for improving the efficiency of a well pump are disclosed. The method includes controlling the elevation at which the well fluids enter the well to thereby control the amount of each fluid, i.e., oil and water, being lifted by the well pump and further contemplates the cooling of the well fluids prior to their passage to the pump, whereby pumping efficiency is increased. This abstract is not to be construed in any way to define or limit the invention set forth below.

15 Claims, 12 Drawing Figures PATENTmm m 381 1; 51 0- IVENTOR.

JOE 0. ROGERS BY BROWN J. WOOLLEY PATENTEUHAY 2 1 1914 O0 oooooooa SHEET 2 [IF 4 JOE C. ROGERS BROWN J. WOOLLEY INVENTOR.

ATTORNEYS Pmmfinmnm 3811.510

5 INVENTOR. F JOE 0. ROGERS 13y BROWN J. WOOLLEY WELL PUMPING METHOD AND APPARATUS BACKGROUND OF THE INVENTION In wells which require the use of well pumps, the well fluids in the producing formation consist primarily of oil and water with possibly some gas. Since it is desirable that the pump lift as much oil as possible on each stroke without pumping large amounts of water, the relative position of the oil-water interface in the formation with respect to the inlet to the well is important. If the well inlet is located improperly, then the pump may be pumping mostly water and very little oil. The problem of maintaining the proper relationship between the well inlet and the oil-water interface is complicated by the fact that the interface changes as pumping continues. To adjust the well inlet it has heretofore been necessary to remove the tubing string from the well bore which is a time-consuming and expensive operation.

Another factor affecting the efficiency of a well pump is the heat of the well fluids. If such fluids are of a relatively high temperature, pumping efficiency is reduced and possible damage to the pump seals or other components may result.

SUMMARY OF THE INVENTION This invention relates to an improved well pumping method and apparatus for pumping oil from a subsurface formation. v

The invention eliminates the problem of the pump having to handle an excessive volume of water by adjusting the elevation of the well fluids inlet into the well relative to the oil-water interfacewithin the formation to control the oil-water mixture drawn from said formation. This controls the volume of water flowing to the pump inlet and increases the volume of oil being pumped. Further, if the well has a high bottom hole temperature by reason of hot well fluids, proper adjustment of the inlet to control the water results in a control of such bottom hole temperature and this, in turn, reduces the problems and cost of treating both the oil and water at the surface.

The invention also provides for cooling the well fluids before such well fluids pass through the pump, whereby the major portion of the fluids handled by the pump are relatively cool liquids. Such cooling and condensing is accomplished by a heat exchanger disposed in the well below the pump inlet.

A primary object of the invention is to provide a well pumping method and apparatus, wherein the elevation of the well fluids inlet at the bottom of the producing well relative to the oil-water interface is adjusted to control the oil-water mixture entering the well to thereby control, as above noted, bottom hole temperature and water production; by controlling the water, the pump is not required to handle excessive volumes of water. The adjustment is made without the necessity of removing the tubing and is accomplished through the tubing after the well pump is removed or altematively, is made by manipulating said production tubing without the necessity of removing the well pump.

Another object of this invention is to provide an improved well pumping method and apparatus which includes cooling the oil and other well liquids by means of a heat exchanger before such liquids are passed through the well pump to thereby assure that substantially all of the fluids handled by the pump means are relatively cool liquids which greatly increases pumping efficiency.

A further object is to provide an improved apparatus, of the character described, which includes an improved friction means anchor device for frictionally supporting within the well casing a well liner assembly having the well fluids inlet, whereby the inlet is maintained at the desired elevation but may be readily adjusted to and firmly supported in different positions as well conditions dictate.

Still another object is to provide an apparatus of the character described, having an improved heat exchanger located below the well pump and which has a coolant medium circulated to it by lines extending from the surface so that the coolant medium does not mix with the well fluids. If desired, the lines through which the coolant medium flows may be insulated to increase the efficiency of the heat exchanger.

Other objects will be apparent from the drawings, the specification and the claims.

- BRIEF DESCRIPTION OF THE DRAWINGS In the drawings, wherein like reference numerals indicate like parts, and wherein illustrative embodiments of this invention are shown:

FIG. 1 is a schematic view of a producing well having the improved apparatus comprising this invention disposed therein;

FIG. 2 is a schematic view of the lower portion of the producing well and illustrating the manner in which the inlet conductor of said well may be adjusted;

FIG. 3 is a view partly in elevation and partly in section of the upper portion of the liner assembly which is adapted to be set within the well casing and also showing the setting tool which locates said assembly within the well;

FIG. 3A is a continuation of FIG. 3 illustrating the lower portion of said liner assembly;

FIG. 4 is an enlarged view partly in elevation and partly in section of the anchor device which supports the inlet conductor assembly, said anchor device being shown inan unset position;

FIG. 5 is a view similar to FIG. 4, showing the anchor device in its set position;

FIG. 6 is a horizontal cross-sectional view taken along line 66 in FIG. 4;

FIG. 7 is a horizontal cross-sectional view taken along line 77'in FIG. 4;

FIG. 8 is a schematic view, similar to FIG. 1, illustrating the tubing acting as the means for adjusting the liner assembly within the well;

FIG. 9 is a view partly in section and partly in elevation of the mechanical heat exchanger which is disposed below the well pump inlet;

FIG. 10 is a horizontal cross-sectional view taken on the line 10l0 of FIG. 9; and

FIG. 11 isa horizontal cross-sectional view taken on the line 11-11 of FIG. 9.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In thedrawings, the letter A (FIG. 1) illustrates a production well which includes the usual well casing 10 and well tubing or production string 11; the standard well head'equipment 12 and 12a seals ofi between the tubing and casing and between the tubing and pump rods 13 which extend downwardly within the well to a well pump 14. The pump lifts the well fluids to the surface through the tubing and said fluids are discharged through an outlet line 11b. A heat exchanger H which will be hereinafter described-in detail, is connected in the tubing string below the pump 14 and serves to cool hot well fluids prior to their passage to the pump. Such cooling increases pump efficiency.

The lower end of the well is in communication with the producing formation F, and a liner assembly generally indicated by the letter B is .mounted within the lower end of the casing. The assembly includes a liner 15 having a well fluids inlet or screen portion including inlet openings 16 through which well fluids are introduced into the well and is frictionally suspended in the casing by means of a frictional type anchor device 17. A packer 18 seals of the annulus between the liner assembly and the well casing.

Well fluids may flow into the lower portion of the well through the well fluids inlet provided by openings 16 in the linerassembly and then upwardly into the lower end of the tubing; when the pump 14 is operated, the well fluids will be pumped to the surface in the usual manner. Although a well pump is preferable,

other means of artificially lifting the well fluids may be used. I

As is well known, each formation normally contains an oil and water interface which is indicated bythe heavy horizontal line I. In order to assure that the pump 14 is not required to handle an excessive volume of water, the inlet portion of the liner 15 is primarily maintained in a desired position relative to the oil-water interface by the frictional anchor device 17; the maintenance of proper position will be assisted by the frictional engagement of the packer 18 as well as by the sand accumulation about the lower portion of the liner. If the interface should rise, which would increase water production (FIG. 1), it is only necessary to slide the liner assembly B upwardly within the well casing to a higher position, whereby a lesser number of the inlet openings 16 will communicate with the water; such adjustment of the liner assembly changes the oil-water mixture which is writhdrawn from the well.

The adjustment of the assembly is carried out without removing the tubing 11 from the well. As schematically shown in FIG. 2, the adjustment is effected by first removing the well pump 14 and its rods 13 from the tubing, after which a conventional spear or gripping tool 19 is lowered by means of suitable rods 20 downwardly into the upper portion of the anchor device 17. Through manipulation of the rods 20, the spear is actuated to grip the bore of the anchor deviceand the liner assembly B is moved to the desired elevation.

The details of the spear or gripping tool 19 are not shown since there are many well-known tools available; one example of such tool is the rotary releasing spear manufactured by the Baash-Ross Division of Joy Manufacturing Co. and shown at page 433 of the 1969-70 Composite Catalog. The important feature is to make the adjustment of the liner assembly without having to remove the entire tubing string 11, which is a timeconsuming and expensive opera-tion.

After the'inlet portion of the liner 15 is properly adjusted, the spear 19 is released and is removed from the well. The. pump 14 and its rods are then run back into the tubing and the well production proceeds with they inlet portion of the liner raised with respect to the wa,-.

ter-oil interface I to assure that the pump is not pumping excessive water volume.

The particular apparatus which includes the liner assembly B and its associated packer and anchor device is subject to variation but one preferred form of apparatus is illustrated in FIGS. 3, 3A, 4 and 5. The liner 15 has its upper end coupled by means of a tubular section 21 with the lower end of the packer 18. This packer may be a well known pin type packer which is set by applying weight to its upper end. When the lower end of the liner 15 engages the bottom of the production well, weight is applied to shear a pin (not shown) in the packer 18 thereby allowing its packer element to be expanded into sealing position with the casing wall. After being set, a pin type packer is locked in set position to maintain its packing element in contact with the casing. One type of pin type packer, manufactured by Brown Oil Tools, Inc. and shown at page 922 of the 1969-70 Composite Catalog, has been found satisfactory.

' Theupper end of packer 18 is connected to the frictional anchor device 17 which is in turn connected through left-hand threads 22 with a setting tool 23.

-The setting tool includes an outer setting sleeve 24 which is secured to a lowering pipe 25. The usual bumper jar 26 which includes telescoping sections is also secured to the lowering pipe and is disposed within the sleeve 24. The lower end of the jar is connected by the left-hand threads 22 to the upper end of the anchor device 17.

ln lowering the apparatus shown in FIGS. 3 and 3A into the well, the parts are in the position shown and a plurality of bowed friction spring S of the anchor device l7 are in a, retracted position. The apparatus is lowered until the lower end of the liner 15 engages the bottom of the well, after which a sufficient downward force is applied through the anchor device to the packer 18 to move it into its set position. Thereafter, as will be explained in detail, the setting tool 23 is utilized to move the friction springs S into engagement with the casing wall whereby the inlet conductor assembly is supported within said casing. Since the packer 18 is in set position, its frictional engagement with the casing wall will assist in supporting the assembly. After the anchor device is set, the setting tool 23 is removed from the well by releasing the left-hand thread 22, thereby leaving the liner assembly in the well, as shown schematically in FIG. 1. Although the left-hand threads have been found satisfactory, other types of a releasable connection, such as a .I-slot, may be employed.

Varioustypes of anchor devices may be employed for frictionally supporting the liner assembly, but a preferable type is illustrated in FIGS. 4 and 5. The anchor device 17 includes a central mandrel 27 which has the left-hand connecting threads 22 in the upper end of its bore. On the lower portion of the exterior of the mandrel is mounted a pair of spaced annular expanders 28 a second inward bow portion S2is formed at the lower end of each spring; above the portion 8-1 is an outwardly bowed portion S-3 and above portion S2 is a second outwardly bowed portion S4. The inwardly bowed portions of the spring are adapted to coact with the spaced expanders28 and 29 which-are securedto the central mandrel. When shear pins'3-3 are maintaining the parts in the positionshown in FIG. 4, the in wardly bowed portions- S1 and S2 of each spring S are at a different elevation than the

expanders

28 and 29 and outwardly bowed portions S.-3- and 8-4 of the springs are retracted. With the parts in this position, the anchor device may be lowered within the well casing without said springs dragging on the casing wall.

For latching the outer bodyv in a downward position relative to the inner mandrel, the cage or body is formed with. a recessv 34 withinwhich is mounted a locking ring 35. When the pins 33 are sheared and the body or cage moves downwardlyv on the mandrel, the locking ring 35 is adapted to move into a locking recess 35a formed in the exterior of the mandrel. In order to properly locate. the locking ring 35 relative to the recess, a stop ring 36 secured on the. exterior of the. mandrel is adapted to be engaged by the lower end of the the weight is applied to the body 30 throughthe setting;

sleeve 23. The lower end of the sleeve 23 may engage the upper end of the body by reason of the telescoping sections of the bumper jar 26. This fractures the shear pins 33 and permits the body .to move downwardly relative to the inner mandrel 27 to the position of FIG. 5.- In this position the inwardly directed bowed portions S1 and S2 of the springs S have movedupwardly on the

expanders

28 and 29 to urge the outwardly bowed portions S3 and'S4 of the springs into tight frictional contact with the wall of the casing 10. By the time the. springs have reached this position relative to the expanders, the latch ring 35 has engaged within the groove 35a while the stop ring 36 has been engaged by the lower end of the cage or body 30. The anchor device is thus locked in its position frictionally engaging the well casing.

Since the liner assembly is maintained in its position within the well casing by the frictional contact of the springs S assisted by the frictional engagement of the packer element with the wall of the casing and the sand surrounding the screen, said conductor is capable of being moved relative to the casing by means of a tool such as the spear 19. It is merely a matter of gripping the inlet conductor assembly and overcoming the frictional engaging forces, after which the assembly may be slid along the wall of the casing to any desired position relative to the formation.

As above described, the use of the sprear '19 for shifting the liner assembly B does not require removal of the tubing string 11, although the well pump 14 and its rods must be removed. It may be desirable in many instances to arrange the apparatus so that this adjustment may be made without having to remove the well pump from the tubing. As is well known, the pump is connected to the surface through pump rods and the removal and replacement of the same involves time and labor.

In FIG. 8, a form of the invention is shown in which a tubular extension 37 projects downwardly from the tubing, 11 below the pump. The lower portion of said extension includes a suitable means capable of being operated by the tubing string 11 for connecting the same to the anchor device 17. As shown, this connecting means comprises radially extending connecting pins 38'adaptedto be'received within J-slots 39 in the upper end of anchor device 17-. Thus, whenever it is desired to adjustthe liner assembly, it is only necessary tomanipulate the tubing to connect the extension of the tubing string with the liner assembly Band move the latter to a different elevation with respect to the oil-water interface within the formation F. It is-understood that other detachable type means can be employed in lieu pump l4'for the purpose of cooling the well fluids prior to their passage to said pump. The heat exchanger conducts a coolant medium, such as water, into heat exchange relationship with hot well fluids entering the well before they are passed through the pump 14 without mixing the coolant medium with said well fluids. Because'the heat exchanger is connected in the lower portion of the tubing string, it is desirable that said heat exchanger be designed to provide maximum heat exchange surface in a minimum length or vertical area within the bore. The use of the heat exchanger H assuresthat any hot well fluids are cooled so that the pump handles only relatively cool liquids, with the result that the pump efficiency is increased and the components of the pump, such'as seals and the like, are protected against possible damage by reason of excessive heat.

A preferred. construction of heat exchanger is shown in FIGS. 9 and 10. Such heat exchanger includes a central mandrel 40 which has its upper end adapted to be attached to the lower end of the well tubing string 11, thereby locating the heat exchanger below the well pump 14. An outer shell or housing 41 of larger diameter than the mandrel surrounds said mandrel to form an annular space between the parts. The upper end of the annular space is closed by an annular headeror ring 42 which is welded to the exterior of the mandrel 40'and 'to the upper end of the shell 41. The lower end of the shell is closed by'a similar header or ring 43.

An upper annular chamber 44 is formed between the top header 42 and a ring 45 spaced downwardly therefrom, the latter also being welded or otherwise attached'to the mandrel and housing. A lower annular chamber 440 is formed at the lower end of the space between the shell and mandrel by a ring 45a located in spaced relationship above the lower header 43. A vertical conductor 46 projects downwardly in the space between the shell and mandrel extending through the top header 42, upper annular chamber 44, rings 45 and 45a and into the lower chamber 44a. The upper end of the conductor 46 has an extension 46a to which a coolant medium return line 47 may be connected and the latter extends upwardly to the surface of the well, whereby a coolant medium, such as water, is conducted upwardly from the lower chamber 44a of the heat exchanger.

A plurality of heat exchange tubes 48 extended between the upper chamber 44 and the lower chamber 44a to establishcommunication therebetween and to locate the tubes in the annular area or space between the mandrel and shell. The coolant medium is conducted from the surface through a pipe 49 into the efficiency and to obviate possible v with the plurality of tubes through which the coolant medium is conducted so that maximum heat exchange occurs between the well fluids and coolant in said I 7 tubes.

After being cooled, the well fluids flow upwardly through the mandrel 40 and into the lower end of the tubing string 11 and then to the inlet of the well pump.

Although the inlet line 49 and the return pipe 47 may be permanently connected to their respective conduc-. tors, in which case said line and pipe are run simultaneously with the tubing string and heat exchanger, it may be desirableIto removably connect said line and conductor to the heat exchanger so that each may be run and removed independently of the tubing and heat exchanger. If the line and'conductor are to be handled separately, the upper end of the mandrel carries an inclined-guide head 50 having an inclined guide surface 50a. At the lower end of said guide surface, two opening s 51 and'52 are provided for receiving and landing the lower ends of the line 49 andthe return pipe 47.

- After the heat exchanger is run with the tubing string and said string is in the well, the inlet line 49 is lowered within the annulus between the tubing and the casing and the inclined guide surface 50a of the guide 50 guides said line into a landed and sealed position in the opening 52to establishcommunication with the upper chamber 44. Thereafter, the return pipe 47 is run separately and is guided and landed into a sealed position in the opening 51 which communicates with the lower chamber 44a. Whether the inlet line 49 and the return pipe 47 are run with or separately from the heat exchanger, the manner of positioning the same does not affect the function of the heat exchanger. In each case a coolant medium is circulated downwardly from the surface to the mechanical heat exchanger, is passed in heat exchange relationship with the well fluids'andth'e heated coolant medium is returned to the surface. This assures that the well fluids being handled by the pump means 14 are'sufficiently cooled to increase pumping damage to the components of the pump.

From the foregoing, it will be seen that an improved method and apparatus which greatly increases well pumping efficiency is provided. The inlet from the producing formation into the well is readily adjustable without removing the well tubing from the well. As has been explained, the adjustment may be accomplished by merely removing the well pump and rods and lowering a spear through the well tubing; or, if desired, the' adjustment may be made with the tubing string itself.

The adjustment assures that the well pump is not han- I dling excessive volumes of water and, therefore, the

primary purpose of the pump in pumping oil from the production formation is accomplished. I

The provision of a heat exchanger below the pump inlet assures that in any hotiwellwhich is encoun-- tered, the heated well fluids will be sufficiently cooled to insure pumping efficiency and to prevent any damage to thevarious seals or other components of the well pump. I

The foregoing disclosure and description of the invention are illustrative and explanatory thereof, and various changes in the size, shape and materials, as well as in the details of the illustrated construction, may be made within the scope of the appended claims without departing from the spirit of the invention.

What is claimed is:

l. A well pumping method for producing well fluids from a subsurface formation of a well through a flow string including the steps of,

locating a well fluids inlet adjacent the producing formation, which inlet has communication with the flow string,

pumping the well fluids upwardly through the flow string'to the surface, and I adjusting the elevation of the well inlet in accordance with the oil-water interface in the formation to control the oil-water mixture entering the flow string to-thereby control the volume of water to be handled by the pumping step,

' said adjustment of the inlet being made without removal of .the flow string from the well.

2. A well pumping method as set forth-in claim 1, wherein I said adjustment of the inlet is made through the bore of said flow string.

3. A well pumping method as set forth in claim 1, wherein said adjustment of the inlet is made by manipulating the flow string.

4. A well pumping method'as set forth in claim 1, with the additional step of cooling the well fluids after entry into the flow string but prior to their being subjected to the pumping step by passing a cooling medium in heat exchange relationship with the well fluids without mixing any of the cooling medium with the well fluids.

5. An apparatus for recovering well fluids from a subsurface producing formation through a well, comprising I face,

a well fluid inlet below said tubing string through which fluids flow from the formation into said string,

pump means located within the tubing string pumping the well fluids to the surface,

a-heat exchanger below the pump means and forming a heat exchange zone to cool the well fluids prior to their passage to the pump, and

means for cycling a cooling medium through said heat exchanger without mixing said cooling medium with the well fluids,

said means forcycling said cooling medium comprises conductors extending downwardly from the well surface to the heat exchanger with the annulus between said tubing string and the well bore,

means for detachably connecting each conductor to the upper portion of the heat exchanger so that said conductors may be run into or removed from the well independently of each other and independently of the tubing-string, and

for

a tubing string within the well extending to the surguide means for guiding said conductors into engagement with said means for detachably connecting said conductors.

6. An apparatus for recovering well fluids from a subsurface producing formation through a well, comprismg a tubing string within the well extending to the surface,

a well fluid inlet below said tubing string through which said fluids flow from the formation into said string,

pump means located within the tubing string for pumping the well fluids to the surface,

a heat exchanger below the pump and forming a heat exchange zone to cool the well fluids prior to their passage to the pump,

a liner assembly, and

anchor means for frictionally supporting said assembly at a desired elevation with respect to the oilwater interface in the formation.

7. An apparatus as set forth in claim 6, including means operable from the surface of the well without removing the tubing string for changing position of the liner assembly to change the position of the inlet relative to the oil-water interface of the formation.

8. An apparatus as set forth in claim 6, including means operable by manipulating the tubing string for adjusting the position of the liner assembly and thereby changing the position of the inlet relative to the oil-water interface of the formation.

9. An apparatus as set forth in claim 6 including a gripping tool mounted on the lower portion of the tubing string and operable by a manipulation of said string to engage the liner assembly so that following such engagement, a vertical movement of the tool will effect a movement of the assembly to change the elevation of the liner inlet relative to the oil-water interface in the formation.

10. An apparatus for recovering oil from a subsurface formation through a well comprising,

a tubing string within the well extending to the surface,

a well fluid inlet below said tubing string,

pump means within the tubing above the inlet for pumping the oil to the surface,

a heat exchanger mounted on the tubing string below the pump means to cool the oil and other fluids prior to their passage to the pump,

said heat exchanger comprising a chamber at each end and cooling tubes extending between said chambers,

.a liner assembly defining the well fluid inlet, and

12. An apparatus as set forth in claim 10, including a liner assembly defining the well fluid inlet,

anchor means for frictionally supporting said assembly at a desired elevation with respect to the oilwater interface in the formation, and

means operable from the surface of the well for moving the liner assembly to change the position of the liner assembly. 13. An apparatus as set forth in claim 10, including a liner assembly defining the well fluid inlet,

anchor means for frictionally supporting said assembly at a desired elevation with respect to the oilwater interface in the formation,

means operable from the surface of the well for moving the liner assembly to change the position of the liner assembly,

said anchor means including,

a central mandrel,

a'tubular body capable of movement axially along said mandrel,

frangible means for releasably securing said body against movement relative to said mandrel,

friction support strings carried by the tubular body and engageable with the well bore wall when said body moves relative to said mandrel in one direction, and

coacting locking means on the mandrel and body to latch the body against further movement relative to the mandrel to maintain the support springs in engagement with the wall of the well bore.

14. The apparatus of claim 13, wherein said locking means includes a latch ring and a groove, one on said mandrel and the other on said body.

15. The apparatus of claim l3,wherein said support springs comprise spring members having an inwardly bowed section, and I an expander adapted to coact with the bowed section of each spring member to move said member radially outwardly.

Claims

1. A well pumping method for producing well fluids from a subsurface formation of a well through a flow string including the steps of, locating a well fluids inlet adjacent the producing formation, which inlet has communication with the flow string, pumping the well fluids upwardly through the flow string to the surface, and adjusting the elevation of the well inlet in accordance with the oil-water interface in the formation to control the oil-water mixture entering the flow string to thereby control the volume of water to be handled by the pumping step, said adjustment of the inlet being made without removal of the flow string from the well.

2. A well pumping method as set forth in claim 1, wherein said adjustment of the inlet is made through the bore of said flow string.

4. A well pumping method as set forth in claim 1, with the additional step of cooling the well fluids after entry into the flow string but prior to their being subjected to the pumping step by passing a cooling medium in heat exchange relationship with the well fluids without mixing any of the cooling medium with the well fluids.

5. An apparatus for recovering well fluids from a subsurface producing formation through a well, comprising a tubing string within the well extending to the surface, a well fluid inlet below said tubing string through which fluids flow from the formation into said string, pump means located within the tubing string for pumping the well fluids to the surface, a heat exchanger below the pump means and forming a heat exchange zone to cool the well fluids prior to their passage to the pump, and means for cycling a cooling medium through said heat exchanger without mixing said cooling medium with the well fluids, said means for cycling said cooling medium comprises conductors extending downwardly from the well surface to the heat exchanger with the annulus between said tubing string and the well bore, means for detachably connecting each conductor to the upper portion of the heat exchanger so that said conductors may be run into or removed from the well independently of each other and independently of the tubing string, and guide means for guiding said conductors into engagement with said means for detachably connecting said conductors.

6. An apparatus for recovering well fluids from a subsurface producing formation through a well, comprising a tubing string within the well extending to the surface, a well fluid inlet below said tubing string through which said fluids flow from the formation into said string, pump means located within the tubing string for pumping the well fluids to the surface, a heat exchanger below the pump and forming a heat exchange zone to cool the well fluids prior to their passage to the pump, means for cycling a cooling medium through said heat exchanger without mixing said cooling medium with the well fluids, a liner assembly, and anchor means for frictionally supporting said assembly at a desired elevation with respect to the oil-water interface in the formation.

10. An apparatus for recovering oil from a subsurface formation through a well comprising, a tubing string within the well extending to the surface, a well fluid inlet below said tubing string, pump means within the tubing above the inlet for pumping the oil to the surface, a heat exchanger mounted on the tubing string below the pump means to cool the oil and other fluids prior to their passage to the pump, said heat exchanger comprising a chamber at each end and cooling tubes extending between said chambers, means for conducting a cooling medium to a chamber of the heat exchanger from the well surface, and said conducting means being located in the annulus between the tubing string and well bore and conducting said medium to the heat exchanger without mixing of the cooling medium with the oil and other fluids passing to the pump.

11. An apparatus as set forth in claim 10, including a liner assembly defining the well fluid inlet, and anchor means for frictionally supporting said assembly at a desired elevation with respect to the oil-water interface in the formation.

12. An apparatus as set forth in claim 10, including a liner assembly defining the well fluid inlet, anchor means for frictionally supporting said assembly at a desired elevation with respect to the oil-water interface in the formation, and means operable from the surface of the well for moving the liner assembly to change the position of the liner assembly.

13. An apparatus as set forth in claim 10, including a liner assembly defining the well fluid inlet, anchor means for frictionally supporting said assembly at a desired elevation with respect to the oil-water interface in the formation, means operable from the surface of the well for moving the liner assembly to change the position of the liner assembly, said anchor means including, a central mandrel, a tubular body capable of movement axially along said mandrel, frangible means for releasably securing said body against movement relative to said mandrel, friction support strings carried by thE tubular body and engageable with the well bore wall when said body moves relative to said mandrel in one direction, and coacting locking means on the mandrel and body to latch the body against further movement relative to the mandrel to maintain the support springs in engagement with the wall of the well bore.

15. The apparatus of claim 13, wherein said support springs comprise spring members having an inwardly bowed section, and an expander adapted to coact with the bowed section of each spring member to move said member radially outwardly.