US3368628A - Multiple zone well completion with common inlet and production tubings - Google Patents

Description

- Feb. 13, 1968 c. .1. COBERLY 3,363,628

MULTIPLE ZONE WELL COMPLETION WITH COMMON INLET AND PRODUCTION TUBINGS Filed March 4, 1965 5 Sheets-Sheet l fixer .1.

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MULTIPLE ZONE WELL COMPLETION WITH COMMON INLET AND PRODUCTION TUBINGS Filed March 4, 1965 5 Sheets-Sheet 2 INVENTOR. CLfiREA/CE cl. 60859.4

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MULTIPLE ZONE] WELL COMPLETIQN WITH COMMON INLET AND PRODUCTION TUBINGS Filed March 4, 1965 5 Sheets-Sheet 5 Lfl9EA/CE d. Case-24y, YINVENTOR,

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C. J. COBERLY MULTIPLE ZONE WELL COMPLETION WITH COMMON Feb. 13, 1968 INLET AND PRODUCTION TUBINGS 6 Sheets-Sheet 4 Filed March 4, 1965 y 3 R L E 6 9 7 2 O m w w w m .L W M r N\\\.\ W E 4 x \\\F a E m m a F W E a 0 |Ii| I |3 1 E 1 M Y w r. L I 4 B E H w L 6 p w M 3 2 LL 2 [J 0 @5 a /A E w Feb. 13, 1968 INLET AND PRODUCTION TUBINGS 5 Sheets-Sheet Filed March M Wm a 1 M W W, 4 0 a. 8 0 B V E 1 8 23 0N M E 12%22 m o 5 v o w u N y a fi g. f a E 6 M v r m y m M M @m n w @0 v 4 $5 2% a 2& 2402 62w 2 2 a 1/9 0 235 2922/\2/5 i 2 L Zia! i vw {F /TL d 5 Z Z 7/f/ f, Z m fiffi E I \N g fire 10.

United States Patent 3,368,628 MULTIPLE ZONE WELL COMPLETION WITH COM- MON INLET AND PRODUCTION TUBINGS Clarence J. Coberly, San Marino, Calif., assignor to Kobe, Inc., Huntington Park, Calif., a corporation of California Filed Mar. 4, 1965, Ser. No. 437,105 9 Claims. (Cl. 16668) ABSTRACT OF THE DISCLOSURE A multiple-zone oil-well completion having a common inlet tubing in communication with the various zones above its lower end and connected at its lower end to a common production tubing alongside the inlet tubing, the two tubings forming a U-tu'be. A fluid operated pump in the production tubing pumps oil downwardly through the inlet tubing and then upwardly through the production tubing while gas flows upwardly through the inlet tubing. A supply tubing conveys operating fluid under pressure to the pump to operate same. A fluid operated selector valve in the inlet tubing selects the zone to be produced. A fluid operated control valve in the supply tubing causes the selector valve to select a different zone each time the pump is stopped and restarted by decreasing and subsequently increasing the operating fluid pressure in the supply tubing.

Summary and objects of the invention The present invention relates in general to oil well completions, and has as its basic object the provision of a multiple zone completion utilizing a tubing system which includes a common inlet tubing in communication with the various zones above its lower end and connected at its lower end to a common production tubing for all of the zones, in combination with a selector means for selectively placing the different zones in fluid communication with the inlet tubing. Preferably, the inlet and production tubings are in parallel, i.e., side-by-side, relation.

Another basic object of the invention is to provide a well completion of the foregoing nature wherein the tubing system is capable of achieving extremely effective separation of the oil and gas produced by each zone during production of oil from such zone by pumping, the gas produced by each zone flowing upwardly to the surface through the inlet tubing, and the oil produced by each zone being pumped upwardly to the surface through the production tubing.

An important object is to produce the various zones one at a time without any significant intermingling of either the oil or the gas from the different zones.

Another important object of the invention is to provide an oil well completion of the foregoing general nature which is capable of producing oil and gas from different zones efliciently and at adequate rates, even in small holes, using pumps of various types, such as a rod operated pump, a fixed fluid operated pump, a free fluid Operated pump, a submersible electric pump, and the like. The tubing system of the invention may also be utilized in some instances to produce the different zones in other ways, as by flowing the various zones simultaneously or sequentially with or without gas lifting. Further, the tubing system of the invention may be utilized to produce some of the zones by pumping and to produce the remaining zones in other ways, as by flowing. However, since the invention is intended primarily for production by sequential pumping of the various zones because it is capable of achieving eflic-ient separation of the oil and gas produced by each zone, the present dis- 3,368,628 Patented Feb. 13, 1968 closure will be directed primarily to producing each zone by pumping, and particularly pumping with a free fluid operated pump.

Considering the manner in which the foregoing principal objectives may be achieved, the invention preferably, but not necessarily, utilizes a casingless completion wherein the tubings of the tubing system are cemented in place in an open bore or hole, as disclosed in my Patent No. 2,939,533, granted June 7, 1960. As more fully discussed in the patent, such a completion has various basic advantages, among these being a smaller well bore for a tubing system involving a given number of tubings of given sizes, accompanying reductions in drilling costs, the elimination of the cost of a casing (except for a surface casing where required to protect underground fresh water supplies, or the like), superior support for the surrounding formations as the result of cementing the tubing system in place, and the like. However, the tubing system of the invention may also be used in casing with packers separating the various zones.

The invention further contemplates, and an important object thereof is to provide, an oil well completion, and

' preferably a casingless, cemented-in-place completion of the foregoing nature, wherein the inlet tubing and the production tubing cooperate to form, in effect, a U-tube, and wherein fluid from each producing zone is admitted into the inlet tubing at a level above the lower end thereof. Preferably, communication between each producing zone and the inlet tubing is achieved by perforating the inlet tubing, and the cement surrounding it, after the tubing system has been cemented in place in the well, utilizing any suitable perforating equipment. With this procedure, it is necessary to drill the well at least into the lowermost producing zone a sufficient distance to locate the lower end of the U-tu-be below the lowermost level at which the inlet tubing is to be perforated. Normally, unless the lowermost producing formation is extremely thick, the well must be drilled to a level sufficiently below such formation to achieve eflicient oil and gas separation in the manner discussed hereinafter.

More particularly, an important object of the invention is to interconnect the lower ends of the inlet and production tubings in fluid communication at a level considerably below that at which the lowermost producing formation communicates with the inlet tubing, and to pump oil from the various zones upwardly to the surface through the production tubing, preferablyby means of a pump located within the production tubing adjacent the lower end thereof. With this construction, as each zone is pumped, the oil from such zone must flow downwardly through the inlet tubing to the inlet of the pump. At the same time, gas produced by the zone in question flows upwardly through the inlet tubing and is drawn off at the surface. Thus, the liquid and gaseous components of the well fluid entering the inlet tubing from the zone being produced flow in opposite directions in the inlet tubing, the gaseous components flowing upwardly to the surface and the liquid components flowing downwardly to the lower end of the inlet tubing and thence to the inlet of the pump in the production tubing. By locating the lower end of the U-tube formed by the inlet and production tubings an adequate distance, e.g., 50 to feet, or more, below the perforations through which fluid from the lowermost zone enters the inlet tubing, excellent gas-oil separation is obtained, enabling the pump to operate at maximum volumetric efliciency, which is an important feature. For a more complete disclosure of this gas-oil separating technique, attention is directed to co-pending application Ser. No. 213,434, filed July 30, 1962, by

An essential object of the invention is to provide selector means for selectively placing the various producing zones in fluid communication with the inlet tubing one at a time, and preferably sequentially. With this construction, oil may be pumped from the various zones one at a time, and preferably sequentially, without intermingling, which is an important feature. Such selector means is preferably hydraulically operated, but it may be operated electrically, by gas pressure, mechanically, or otherwise.

Another essential object is to provide separate oilhandling and gas-handling facilities at the surface for the oil and gas produced by the various zones, and to provide selector means for directing the oil and gas from the different zones to the corresponding oil-handling and gas-handling facilities. With this construction, there is no intermingling of oil from the different zones, nor is there any intermingling of gas from the different zones, which is an important feature.

A further object is to provide an installation wherein the selector means for selectively placing the different zones in fluid communication with the inlet tubing, and the selector means for directing the oil and the gas from the different zones to the corresponding oil-handling and gas-handling facilities, are operated in timed relation so that the oil and gas from each zone are routed to the proper oil-handling and gas-handling facilities.

An important object of the invention is to provide a fluid operated selector means for selectively placing the various producing zones in fluid communication with the inlet tubing, and this in fluid communication with the inlet of the pump, which includes valve means in the tubing system adjacent the lower end thereof and controllable from the surface. More particularly, an object in this connection is to provide a fluid operated selector valve in the inlet tubing for selectively connecting the inlet tubing in fluid communication with the different zones, and to provide a control valve in the tubing system and operable from the surface for operating the selector valve.

Yet another important object of the invention is to provide a multiple zone well completion of the foregoing nature wherein the pump is a fluid operated pump adapted to be hydraulically circulated through the production tubing between the surface and an operating position in the well adjacent the lower end of the production tubing. A related object is to provide adjacent'the lower end of the production tubing a standing valve assembly which communicates with the lower end of the inlet tubing, and on which the inlet end of the fluid operated pump is seated when it is in its operating position. Another related object is to provide a supply tubing in the well for conveying operating fluid under pressure, for actuating the fluid operated pump, downwardly from the surface to the fluid operated pump. The supply tubing is preferably a parallel tubing cemented in place along with the inlet and production tubings. Still another related object is to provide a closed system incorporating a return tubing for separately returning to the surface agent operating fluid discharged by the pump. The return tubing is also preferably a cemented-in-place, parallel tubing.

An important object of the invention is to provide a well completion of the foregoing nature wherein the control valve for operating the selector valve to place the different zones in communication with the inlet tubing is responsive to fluid pressure variations in the supply tubing for the fluid operated pump. More particularly, an object in this connection is to provide a control valve which moves the selector valve upwardly from an inoperative position to a different operating position each time the fluid pressure in the supply tubing is reduced from the normal operating pressure to the static pressure due to the head of fluid in the supply tubing. To achieve this, the operating pressure at the well head must be reduced to the return tubing pressure at the well head, or approximately to zero.

Still another object of the invention is to provide such a control valve which causes the selector valve to move upwardly to its different operating positions in sequence so that the different zones can be produced sequentially. Related objects are to provide vertically spaced ports, controlled by the control valve, which stop the upward movement of the selector valve at its successive operating position, and to provide a selector valve which is moved downwardly into its inoperative position by gravity each time the supply tubing pressure at the wellhead is reduced to zero.

An important object of the invention is to provide programming means, preferably at the surface, for varying the pressure in the supply tubing between the operating pressure and the static pressure due to the head of fluid therein according to a predetermined program so as to produce the various zones sequentially according to such program. The exact production program will be determined by various factors, such as the relative productive capacities of the different zones, the relative demands for oil and gas from the different zones, production quotas (if any) for the various zones, and the like. The programming means preferably merely comprises timing means, although it may include means responsive to the liquid level in the inlet tubing, or the like.

Another object of the invention is to provide a bottomhole control valve, for operating the selector valve, which is adapted to be hydraulically circulated through the supply tubing between the surface and an operating position adjacent the lower end of the supply tubing.

Yet another object is to provide a selector valve assembly which can be run in and out of the inlet tubing on a wire line, the same being true of the control valve if desired.

A further object is to provide a selector valve assembly which is adapted to be set in the inlet tubing by slip means actuable by fluid pressure. A related object is to provide a selector valve assembly having packers, for separating the various zones, which are also adapted to be set in the inlet tubing by fluid pressure.

The foregoing objects, advantages, features and results of the present invention, together with various other objects, advantages, features and results thereof which will be evident to those skilled in the multiple-zone oil well producing art in the light of this disclosure, may be achieved with the exemplary embodiment of the invention described in detail hereinafter and illustrated in the accompanying drawings.

Description of the drawings In the drawings:

FIG. 1 is a semidiagrarnmatic view showing in vertical section the upper end of a two-zone well completion which embodies the invention, and showing in elevation surface oil-handling and gas-handling facilities associated with such completion, the portion of FIG. 1 which is shown in vertical section being taken along the irregular arrowed line 11 of FIG. 4;

FIG. 2 is an enlarged downward continuation of FIG. 1, showing down hole portions of the two-zone well completion of FIG. 1;

FIG. 3 is a downward continuation of FIG. 2, showing bottom hole portions of the completion;

FIG. 4 is a horizontal sectional view taken along the arrowed line 4-4 of FIG. 2;

FIGS. 5 and 6 are enlarged, vertical sectional views respectively taken along the arrowed lines 55 and 66 of FIG. 2;

FIG. 7 is an enlarged, vertical sectional view taken along the arrowed line 7-7 of FIG. 3;

FIGS. 8 and 9 are enlarged, horizontal sectional views respectively taken as indicated by the arrowed lines. 8- and *99 of FIG. 2;

FIG. is a vertical sectional view of a control valve forming part of a zone selector means of the invention:

FIG. 11 is a fragmentary view duplicating a portion of FIG. 10, some parts which are shown in vertical section in FIG. 10 being shown in elevation in FIG. 11; and

FIG. 12 is a vertical sectional view of a selector valve forming part of a selector means for directing oil and gas from different producing zones to corresponding oil-handling and gas-handling facilities.

Description of preferred embodiment of the invention. General description Referring initially to FIGS. 1 to 4 of the drawings, these figures illustrate, in a semidiagrammatic manner, a casingless, ceme-nted-in-place, two-zone, U-tube oil well completion 20 which embodies the invention.

More particularly, the well completion 20 includes a bore or hole 22 drilled from the surface 24 downwardly through upper and lower producing formations or zones 26 and 28 and bottomed a substantial distance, e.g., 50 to 100 feet, or more, below the lower zone. Except for a surface casing 30 which may be required in some areas to prevent contamination of subsurface fresh water supplies, or the like, the well bore 22 is preferably uncased in accordance with the practice of the aforementioned Patent No. 2,939,533, although the invention is not limited thereto.

Suspended in the uncased well bore 22 from a well head 32, shown as mounted on the surface casing 30, is a tubing system designated generally by the numeral 34. The tubing system 34 includes an inlet tubing 38 selectively connectible in fluid communication with the producing formations 26 and 28 in a manner to be described hereinafter, and further includes a production tubing 40. The tubings 38 and 40 are preferably positioned in the well bore 22 in parallel or side-by-side relation and are interconnected at their lower ends, at a level 50 to 100 feet, or more, below the lower producing formation 28, in such a manner that they cooperate to form a U-tube 44 similar to the U-tube of the aforementioned Patent No. 3,172,469.

Although, as hereinbefore outlined, the well completion 20 may be produced in other ways, it is particularly applicable to selective production of the upper and lower producing formations 26 and 28 by pumping upwardly through the production tubing 40 oil from the particular formation which is connected to the inlet tubing 38, and by simultaneously producing gas from the formation being pumped upwardly through the inlet tubing. When either zone 26 or 28 is being produced, the U-tube 44 acts to separate the oil and gas from such zone in the manner disclosed in Patent No. 3,172,469.

The well completion 20 illustrated is particularly suit-v able for use with a fluid operate-d pump 46 capable of being circulated through the production tubing 40 hydraulically between the surface 24 and an operating position adjacent the lower end of the production tubing. When the pump 46 is in its operating position, its lower, inlet end 48 is seated on a standing valve assemby 50 carried by the tubing system 34 adjacent the lower end of the production tubing 40. As will be described in more detail hereinafter, the upper and lower zones 26 and 28 are selectively, and preferably sequentially, placed in fluid communication with the inlet tubing 38, the lower nd of the standing valve assembly 50 being connected to the lower end of the inlet tubing through a passage 110 so that oil from the particular formation 26 or 28 being produced is delivered to the inlet of the pump 46.

When the fluid operated pump 46 is in its operating position, it receives operating fluid, such as clean crude oil, under high pressure through a supply tubing 52. The spent operating fluid discharged by the pump 46 may be mixed with the production fluid in an open system and pumped upwardly to the surface through the production tubing 40. However, a closed system for the operating fluid is preferable, the tubing system 34 being shown as including a return tubing 54 for returning the spent operating fluid to the surface 24 separately from the production fluid from the particular formation 26 or 28 being produced. The supply and return tubings 52 and 54 are preferably positioned in the well bore 22 in parallel or side-by-side relation with the tubings 38 and 40.

The entire tubing system 34 iscemented in place in the uncased well bore 22 by a body of cement 56 which surrounds all of the tubings 38, 40, 52 and 54, and which cements off the producing formations 26 and 28. Preferably, the body of cement 56 extends from the bottom of the well bore 22 upwardly at least to a level above the upper producing formation 26. However, it may extend upwardly in the well bore 22 all the way to the surface 24, or at least into the lower end of the surface casing 30, if used. The level to which the body of cement 56 extend upwardly above the upper producing formation 26 depends on the nature of the formations thereabove and the extents to which they require support.

The tubing system 34 may be cemented in place in the well bore 22 by pumping cement downwardly through the inlet tubing 38, such cement being discharged through ports 60, FIGS. 3 and 7. After the necessary or desired quantity of cement has been introduced into the well bore 22 in this manner, the inlet tubing 38 is purged of cement. The necessary equipment and procedure for cementing the tubing system 34 in place to the desired level are more fully disclosed in the aforementioned Patents Nos. 2,939; 533 and 3,172,469. Consequently a further description herein is not necessary.

After the tubing system 34 has been cemented in place, the inlet tubing 38, and the surrounding cement 56, are provided with perforations 62 and 64, respectively, opposite the upper and lower producing formations 2 6 and 28, respectively, to establish fluid communication between the respective producing zones and the inlet tubing. This may be accomplished utilizing conventional perforating equipment capable of being oriented properly to avoid perforating adjacent tubings. Perforating apparatuses of this nature, and the techniques for using them, are so well known that no additional description is required.

Bottom-hole zone selector means Within the tubing system 34 adjacent the lower end thereof is a zone selector means 100, FIGS. 2 and 3, for selectively connecting the upper and lower producing formations 26 and 28 to the inlet tt'ubing 38, and thus to the inlet end 48 of the fluid operated pump 46 through the passage and the standing valve assembly 50.

More particularly, the zone selector means 100 includes a step-type control or relay valve 102 capable of operating a selector valve or selector valve assembly 106 in such a manner as to cause the selector valve to place the upper and lower zones 26 and 28 in communication with the inlet tubing 38 sequentially. Preferably, the control valve 102 and the selector valve 106 are fluid operated, in a manner to be described hereinafter, but they may be otherwise operated, e.g., electrically, or the like.

The control valve 102 is preferably hydraulically movable through the supply tubing 52 between the surface 24 and an operating position adjacent the lower end of the supply tubing. Alternatively, the control valve 102 may be installed and removed through the supply tubing 52 on a wire line.

The selector valve 106 is movable through the inlet tubing 38 between the surface 24 and an operating position adjacent the lower end of the inlet tubing, being set in its operating position hydraulically in a manner to be described. Preferably, the selector valve 106 is installed and removed with a wire line.

Upon one actuation of the selector valve 106 by the control valve 182, the selector valve places the upper zone 26 in communication with the inlet tubing 38 so that upper-zone oil can flow to the inlet end of the standing valve assembly 50 through the passage 110 in the tubing system 34. Similarly, when the control valve 102 next actuates the selector valve 106, the latter places the lower zone 28 in fluid communication with the inlet tubing 38 so that lower-zone oil can reach the inlet end of the standing valve assembly 50 through the passage 110.

The manner in which the control valve 102 is actuated, and the manner in which the selector valve 106 performs the aforementioned functions, will be discussed in more detail hereinafter under appropriate headings.

Surface zone selector means 120 Referring to FIG. 1 of the drawings, the well completion 20 includes at the surface 24 a zone selector means 120 for directing oil produced by the upper and lower zones 26 and 28 to upper-zone and lower-zone oil handling facilities or equipment 122 and 124, respectively,-and for directing gas produced by the upper and lower zones 26 and 28 to upper-zone and lower-zone gas handling facilities or equipment 126 and 128, respectively.

More particularly, the zone selector means 120 includes a control valve 130 which may be similar to the control valve 102 and which is operated in timed relation therewith, as will be described hereinafter. The control valve 130 sequentially actuates (substantially in phase with the upper-zone and lower-zone selections of the selector valve 106) upper-zone and lower-zone oil selector valves 132 and 134 controlling distribution to the respective upper-zone and lower-zone oil handling facilities 122 and 124. Similarly, the control valve'130 sequentially actuates (substantially in phase with the upper-zone and lower-zone selections of the selector valve 106) upperzone and lower-zone gas selector valves 136 and 138 for directing gas from the respective upper and lower producing formations 26 and 28 to the upper-zone and lowerzone gas handling facilities 126 and 128, respectively. As will be discussed hereinafter, the two control valves 102 and 130 are actuated in timed relation by a programming means 140 shown as controlling the flow of operating fluid through a supply line 142 connected to the upper end of the supply tubing 52. (A corresponding return line 144 is connected to the upper end of the return tubing 54.)

The upper-zone and lower-zone oil selector valves 132 and 134 are respectively located in branch oil production lines 146 and 148 which are connected to a common oil production line 150 in communication with the upper end of the common production tubing 40. The branch oil production lines 146 and 148 respectively lead to tho' upperzone and lower-zone oil handling facilities 122 and 124 and may have inserted therein flowmeters 152 and 154 for measuring the oil production from the respective upper and lower zones 26 and 28.

The upper-zone and lower-zone gas selector valves 136 and 138 are respectively located in branch gas production lines 156 and 158 connected to the upper end of the inlet tubing 38 through a common gas production line 159, and respectively connected to the upper-zone and lowerzone gas handling facilities 126 and 128.

The manner in which the control valve 130 actuates the various selector valves 132, 134, 136 and 138 will be discussed in more detail hereinafter.

Running pump 46, control valve 102 and selector valve 106 in and out Interconnecting the production, supply and return tubings 40, 52 and 54 and the production, supply and return lines 150, 142 and 144 is a control valve means 160 for connecting the lines 150, 142 and 144 to the tubings 40, 52 and 54 in various combinations depending upon whether the fluid operated pump 46 and the control valve 102 are in operation in their operating positions, or are being run in or out. When the fluid operated pump 46 and the control valve 102 are in their operating po sitions and in operation, the control valve means 160 connects the production, supply and return lines 150, 142 and 144 to the production, supply and return tubings 40, 52 and 54, respectively.

In order to run the fluid operated pump 46 in, .it is first inserted into the upper end of the production tubing 40. The control valve means is then set in a position to deliver operating fluid from the supply line 142 to the production tubing 40 above the pump 46 to displace the pump downwardly through the production tubing 40. At the same time, the control valve means 160 is set to close the upper end of the supply tubing 52, and to connect the return tubing 54 to the return line 144. As a result, fluid beneath the pump 46 is displaced upwardly through the return tubing 54 by way of a passage 162 connecting the lower end of the return tubing 54 to the lower end of the production tubing 40 adjacent the upper end of the standing valve assembly 50, as shown in FIG. 3 of thedrawings. (Such displaced fluid can also enter the return tubing 54 through a passage 168 until such time as the pump 46 covers such passage.) Since the supply tubing 52 is closed with this procedure, no possibly dirty fluid in the production tubing 40 can enter the supply tithing 52 to contaminate any clean operating fluid therein.

In running the control valve 102 in hydraulically, it is first inserted into the upper end of the supply tubing 52. The control valve means 160 is then set to connect the supply line 142 to the supply tubing 52 to displace the control valve 102 downwardly through the supply tubing 52. If the pump 46 is in its operating position, fluid beneath the control valve 102 is displaced through the return tubing 54 by way of a passage 164, FIG. 3, the control valve means 160 being set to connect the return tithing 54 to the return line 144 and to close the upper end of the production tubing 40. If the pump 46 is not in place, fluid from beneath the control valve 102 may be displaced upwardly through either or both the production and return tubings 40 and 54.

When both the fluid operated pump 46 and the fluid operated control valve 102 are in their operating positions, as shown in FIG. 3 of the drawings, and are in operation, the fluid operated pump 46 receives the operating fluid under pressure required for its actuation by way of an annular clearance around the control valve and by way of a passage 166, FIG. 3. The spent operating fluid discharged by the pump 46 is conveyed to the return tubing 54 'by way of the passage 168. Irrespective of which of the zones 26 and 28 is being produced, the production fluid discharged by the pump 46 bypasses the pump by way of a passage 170 and flows upwardly through the production tubing 40 to the surface. (It will be noted that when the pump 46 is in its operating position, the packers on the usual packer mandrel 172 at the upper end of the pump are positioned in enlarged portions 174 of the production tubing 40 so that the upwardly-flowing production fluid can bypass the packers.)

In order to run the pump 46 out, the control valve means 160 is set to connect the supply line 142 to the return tubing 54, the upper end of the supply tubing 52 being closed and the upper end of the production tubing 40 being connected either to the return line 144, or the production line 150. Under such conditions, the operating fluid under pressure from the supply line 142 flows downwardly through the return tubing 54 and the passage 162 to unseat the pump 46 and move it upwardly in the production tubing 40. Initial upward movement of the pump 46 results from engagement of the usual external seals on the body of the pump with the peripheral walls of the chamber in which the pump is disposed when in its operating position. This initial upward movement is sufficient to move the packers on the packer mandrel 172 upwardly out of the enlarged portions of the production tubing 40 so that they can engage the wall of such tubing. Thereafter, the operating fluid introduced below the pump 46 acts on the packers on the 9 packer mandrel 172 to circulate the pump to the surface 24 in the usual manner for this type of installation.

To run the control valve 102 out, the control valve means 160 is again set to connect the supply line 142 to the return tubing 54, the upper end of the production tubing 40 being closed and the supply tubing 52 being connected to the return line 144, for example. Under such conditions, the operating fluid under pressure flowing downwardly through the return tubing 54 enters the supply tubing 52 beneath the control valve 102 by Way of the passage 164, whereby the control valve 102 is circulated to the surface.

In addition to running the pump 46 and the control valve 102 in and out independently in the foregoing manner, they may also be run in and out simultaneously if desired. Also, the control valve 102 may be run in and out on a wire line if desired.

The selector valve 106 is intended to be run in and out by means of a wire line in the particular construction illustrated.

General operation of control valves 102 and 130 by programming means 140 When the fluid operated pump 46 and the fluid operated control valve 102 are in their operating positions in the tubing system 34, and the control valve means 160 is set to connect the supply, return and production lines 142, 144 and 150 to the supply, return and production tubings 52, 54 and 40, respectively, the fluid operated control valves 102 and 130 are actuated by varying the operating fluid pressure in the supply line 142 and the supply tubing 52. Preferably, such varying of the operating fluid pressure in the supply line 142 and the supply tubing 52 involves utilizing the programming means 140 to shut off the flow of operating fluid under pressure, whereby the fluid pressures at the control valves 102 and 130 are either the maximum values existing When the operating fluid under pressure is flowing to the fluid operated pump 46, or the minimum, static values existing When the flow of operating fluid is shut off by the programming means 140. As will be explained in more detail hereinafter, each time the programming means 140 reduces the fluid pressures at the control valves 102 and 130 from the maximum values to the minimum values and restores them to the maximum values, the control valves 102 and 130 actuate the selector valves 106, 132, 134, 136 and 138 as required to switch production from one of the zones 26 and 28 to the other and to correspondingly switch the routing of the oil and gas from one set of oil and gas handling facilities 122 and 126, or 124 and 128, to the other.

The programming means 140 may operate on any desired time cycle, depending upon such factors as the relative productive capacities of the two zones 26 and 28, the relative demands for oil and gas from these zones, production quotas (if any) for these zones, and the like. Each of the zones 26 and 28 may be produced, before switching to the other, for a time interval ranging from minutes to days, depending upon circumstances. In its simplest form, the programming means 140 may consist merely of a three-way valve, not shown, which connects the supply line 142 to the supply tubing 52 or shuts off the supply line 142. When the three-way valve shuts 011 the supply line 142, it opens the supply tubing 52 to the return line 144 through a bypass line 175. The programming means 140, which is operated by a suitably programmed timer, operates the control valve 102 through the supply tubing 52, and operates the control valve 130 through a line 176 leading from the programming means to the control valve. It should be noted that the three-way valve referred to alternately connects the supply tubing 52 to high and low pressure by alternately connecting it to the supply line 142 and the return line 144.

10 Control valve 102 Referring particularly to FIG. 10 of the drawings, the control valve 102 includes a valve body 180 having a tapered lower end 182 which is engaged with a tapered seat 184 when the control valve 102 is in its operating position. There is an annular clearance 186 around the valve body 180' above the passage 166. Operating fluid under pressure for actuating the pump 46 flows through the annular clearance 186 and the passage 166 to the pump.

Within the valve body 180' adjacent its upper end is a piston 188 vertically reciprocable in a cylinder 190 and biased upwardly by a compression spring 192. The upper end of the piston 188 is exposed to the fluid pressure in the supply tubing 52 through a port 194 in the upper end of the valve body 180. The lower end of the piston 188 is exposed to the fluid pressure in the return tubing 54 through the passage 164, a chamber 196 be low the seat 184 for the control valve 102, and axial passages 198 and 200 through elements to be described hereinafter.

With this construction, when the programming means 140 shuts off the flow of operating fluid to the supply tubing 52, and opens the tubing 52 to the return line 144, the pressures acting on the upper and lower ends of the piston 188 are substantially equalized, both being equal to the static pressures due to the heads of fluid in the supply and return tubings 52 and 54. Under such conditions, the spring 192 displaces the piston 188 to the upper limit of its stroke. Conversely, when the programming means 140 permits the flow of operating fluid under pressure into the supply tubing 52, the fluid pressure acting on the upper end of the piston 188 overcomes the spring 192 and displaces the piston into its lowermost position, shown in FIG. 10 of the drawings.

The piston 188 includes an element 210 which is provided with straight, longitudinal, external splines 212 engaging complementary splines 214 on the valve body 180 to prevent rotation of the piston as it moves upwardly and downwardly. The element 210 is provided internally thereof with helical longitudinal splines 216 meshed with complementary splines 218 on an actuator 220 oscillatable about the vertical axis of the valve body 180. For the particular two-zone completion 20* under consideration, the angle of the splines 216 and 218 and the stroke of the piston 188 are so related as to rotate the actuator 220 through an angle of 180 during each stroke of the piston, the actuator being moved through this angle in one direction during the upward stroke of the piston and being moved through the same angle in the opposite direction during the downward stroke thereof. For a three-zone completion, the angle through which the actuator 220 moves must be 120, for a four-zone completion it must be and so forth.

Fixed to the lower end of the rotary actuator 220 is a rachet member 222 having two jaws spaced 180 apart for the two-zone completion 20 under consideration. (For a three-zone completion, the rachet member 222 requires three jaws spaced apart, for a four-zone completion it requires four jaws spaced 90 apart, and so forth, the same being true of the other rachet members to be described hereinafter.) The rachet member 222 cooperates with a complementary rachet member 224 which is connected to a rotary control valve element 226 by straight, vertical splines. A compression spring 228 biases the rachet member 224 upwardly into engagement with the rachet member 222. Also connected to the control valve element 226 by straight, vertical splines is a rachet member 230 having two jaws spaced apart by and in phase with the jaws of the rachet member 224. The spring 228 biases the rachet member 230 downwardly into engagement with a complementary rachet member 232 fixed to the valve body 180.

With the foregoing construction, each time the piston 188 moves upwardly, the rachet member 222 rotates relative to the rachet member 224 through an angle of 180, while the rachet members 230 and 232 cooperate to prevent rotation of the control valve element 226. During the subsequent downward stroke of the piston 188, the rachet members 222 and 224 cooperate to advance the control valve element 226 through an angle of 180, while the rachet member 230 rotates through the same angle relative to the rachet member 232. Thus, each time the programming means 14-0 reduces the pressure in the supply tubing 52 from its maximum value to its minimum value and restores it to its maximum value again, the control valve element 226 is advanced one angular step of 180. (This angular step will be 120 in the case of a three-zone completion, 90 in the case of a four-zone completion, and so forth.)

The control valve element 226 is provided adjacent its lower end with radial ports 242 and 244 which are vertically spaced apart and which are angularly spaced apart by 180. The inner ends of the ports 242 and 244 communicate with the axial passage 198, which is connected to the return tubing 54 through the chamber 196 and the passage 164. When the control valve element 226 is in one of its operating positions, the radial port 242 communicates with a radial port 246 in the valve body 180. Similarly, when the control valve element 226 is in its other operating position, the radial port 244 therein communicates with a radial port 248 in the valve body 180. The ports 246 and 248 respectively communicate, through ports 250 and 252 and annular channels 254 and 256, with control passages 258 and 260 respectively leading to upper-zone and lower- zone control ports 262 and 264 in the selector valve 106. External annular seals 266 on the valve body 180 isolate the two sets of ports mentioned from each other and from their environment.

With the foregoing construction, the return tubing 54 is connected to the upper-zone control port 262 in one operating position of the control valve element 226, and is connected to the lower-zone control port 264 in the other operating position of the control valve element. Thus, the upper-zone and lower-zone control ports 262 and 264- are vented to the return tubing 54 sequentially as the control valve element 226 is rotated step-by-step. As hereinbefore discussed, the control valve element 226 is advanced step-by-step to accomplish this merely by varying the supply-tubing pressure between its maximum and minimum values under the control of the programming means 140.

As will be discussed hereinafter in considering the selector valve 106 in detail, venting of the upper-zone control port 262 to the return tubing 54 (while closing the lowerzone control port 264) causes the selector valve to place the inlet tubing 38 in communication with the upper zone 26. Similarly, venting of the lower-zone control port 264 to the return tubing 54 (while keeping the upper-zone control port 262 closed) causes the selector valve 106 to connect the lower zone 28 to the inlet tubing 38. The selector valve 106, and the manner in which it performs the foregoing, will now be described.

Selector valve 106 Referring to FIGS. 2, 3 and 5 to 9 of the drawings, the selector valve 106 includes a tubular housing 270 provided at its upper end with slips 271 for setting such housing in the inlet tubing 38 against upward movement therein. As shown in FIG. 5, the slips 271 are provided with downwardly divergent inner surfaces 272 which engage complementary surfaces 273 on the upper end of spectively located above the upper perforations 62, between the upper and lower perforations 62 and 64, and below the lower perforations 64. The upper packer 274 is seated against a downwardly facing annular shoulder 277 on the tubular housing 270. Seated against the lower end of the'upper packer 274 is a collar 278 slidable on the tubular housing 270. A similar collar 279 is seated against the upper end of the middle packer 275 and the two collars 278 and 279 are interconnected by a sleeve 280 which surrounds the tubular housing 270. Similar collars 281 and 282 respectively engage the lower and upper ends of the middle and lower packers 275 and 276 and are interconnected by a similar sleeve 283. The lower end of the lower packer 276 is engaged by another similar collar 284 connected to the upper end of a similar sleeve 285. Referring to FIG. 7, the lower end of the sleeve 285 is connected to a tubular piston 286 slidable in the upper end of a cylinder 287 forming a downward continuation of the inlet tubing 38. The piston 286 has a reduceddiameter portion 288 which is slidable in the lower end of the tubular housing 270.

The upper-zone and lower- zone control ports 262 and 264 communicate with the interior of the cylinder 287 below the piston 286 and, since the control valve 102 always connects one or the other of the control ports 262 and 264 to the return tubing 54 in the manner hereinbefore described, the pressure due to the static head of fluid in the return tubing 54 is always applied to the lower end of the piston 286. Normally, this pressure is higher than the formation pressure in either of the productive zones 26 and 28, such formation pressure acting downwardly on the piston 286. Consequently, a net upward pressure force acts on the piston 286 to set the packers 276, 275 and 274 through the sleeve 285, the collar 284, the collar 282, the sleeve 283, the collar 281, the collar 279, the sleeve 280, and the collar 278. This upward force also acts on the downwardly facing annular shoulder 277 on the tubular housing 270 to urge the latter upwardly to set the slips 271. Thus, the piston 286 serves to set both the slips 271 and the packers 274, 275 and 276.

The tubular housing 270 and the sleeve 280 are provided therein with upper- zone ports 289 and 290, respectively, which communicate with the upper perforations 62 leading to the upper zone 26, thereby admitting fluid from the upper zone into the interior of the tubular housing 270. Similarly, the tubular housing 270 and the sleeve 283 are provided therein with lower- zone ports 291 and 292, respectively, which communicate with the lower perforations 64 to admit fluid from the lower zone 23 into the interior of the tubular housing 270.

The selector valve 106 includes a vertically movable, tubular slide valve 293 which extends entirely through the tubular housing 270, the packer-and-slip-setting piston 286 and the cylinder 287, this slide valve having an upper end 294 which projects upwardly into the inlet tubing 38 above the upper end of the tubular housing 270, and having a lower end 295 which projects downwardly below the lower end of the cylinder 287 into a chamber 296 communicating at its lower end with the passage 110 leading to the lower end of the standing valve assembly 50. As will be discussed in more detail hereinafter, the slide valve 293 is movable upwardly from a lowermost, inoperative position through a lower operative position, wherein the interior thereof communicates with the lower zone 28, to an upper operative position wherein the interior thereof communicates with the upper zone 26, the slide valve being shown in its upper operating position in FIGS. 5 to 7. The length of the chamber 296 is sufiicient to permit the slide valve 293 to move downwardly into its lowermost, inoperative position. The length of the slide valve 293 is such that when it is in its lowermost, inoperative position, the upper end 294 thereof projects upwardly above the upper end of the tubular housing 270.

As shown in FIGS. 3 and 7, the slide valve 293 is suitably sealed relative to the tubular piston 286 and the upper end of the chamber 296, and, as shown in FIG. 6, is provided thereon with lands 297, 298, 299 and 304 which carry seals engageable with the interior of the tubular housing 270, there being a similar land 301, FIG. 5, on the slide valve above the land 297. The slide valve 293 is provided with ports 300 therein between the lands 298 and 299, the spacing of these lands being suflicient to embrace all of the upper-zone ports 289 in the tubular housing 270 when the slide valve is in its upper operating position, and to embrace all of the lower-zone ports 291 in the tubular housing when the slide valve is in its lower operating position. As previously explained, the upperzone and lower- zone ports 289 and 291 communicate with the upper and lower zones 26 and 28, respectively. When the slide valve 293 is in its upper operating position, the lower-zone ports 291 in the tubular housing 270 are isolated between the lands 299 and 304. When the slide valve 293 is in its lower operating position, the lands 297 and 298 isolate the upper-zone ports 289. When the slide valve 293 is in its lowermost, inoperative position, the lower-zone ports 291 are isolated between the lands 297 and 298, and the upper-zone ports 289 are isolated between the land 297 and the land 301, FIG. 5, thereabove. Thus, when the slide valve 293 is in its upper or lower operating position, only the upper or lower zone 26 or 28 communicates with the interior thereof through the ports 300. When the slide valve 293 is in its lowermost, inoperative position, both zones 26 and 28 are isolated completely.

Considering the manner in which the slide valve 293 is moved through its range of positions, the slide valve is provided thereon within the cylinder 287 with a piston 302, FIGS. 3 and 7. The lower end of the cylinder 287 is connected to the supply tubing 52 by way of a passage 303, FIG. 3. Whenever the programing means 140 at the surface 24 interrupts the flow of operating fluid under pressure into the supply tubing 52, the pressure beneath the piston 302 is reduced to that corresponding to the static head of fluid in the supply tubing. Since, as previously pointed out, the pressure due to the static head of fluid in the return tubing 54 is always applied to the lower end of the tubular piston 286 through one or the other of the control passages 258 and 260, the static return tubing pressure always acts on the upper end of the piston 302. Consequently, when the static supply tubing pressure is applied to the lower end of the piston 302, this piston is substantially balanced, with the result that the slide valve 293 moves downwardly into its lowermost, inoperative position under the influence of gravity.

When the programming means 140 subsequently resumes the delivery of operating fluid under pressure to the supply tubing 52, such pressure acts on the lower end of the piston 302 to move the slide valve 293 upwardly. If the control valve 102 has opened the lowerzone control port 264 and closed the upper-zone control port 262, the piston 302 cannot move above the lower-zone control port 264, thereby placing the interior of the slide valve 293 in communication with the lower zone 28 through the lower- zone ports 291 and 292 and the ports 300. Alternatively, if the control valve 102 has closed the lower-zone control port 264 and opened the u per-zone control port 262, the piston 302 will move upwardly as far as the upper-zone control port 262, thereby placing the interior of the slide valve 293 in communication with the upper zone 26 through the upper- zone ports 289 and 290 and the ports 300. Thus, the position of the control valve 102 determines the position the slide valve 293 will assume when the programming means 140 resumes delivery of operating fluid under pressure to the supply tubing 52, and thus determines which of the two zones 26 and 28 is placed in communication with the inlet of the fluid operated pump 46 through the interior 14 of the slide valve 293, the chamber 296-, the passage 110, and the standing valve assembly 50.

It will be understood that while the selector valve 106 has been disclosed specifically for two zones, it can be modified readily to accommodate more than two zones.

In order to prevent a fluid lock from developing between the lowermost land 304 on the slide valve 293 and the tubular piston 286, which fluid lock would prevent the slide valve from descending under the influence of gravity to its lowermost, inoperative position, a port 305, FIG. 6, is provided in the slide valve below the land 304. This port connects the annulus around the slide valve 293 below the land 304 to the interior of the slide valve and thus to the interior of the inlet tubing 38, thereby applying the lowest pressure in the system to the under side of the land 304. Preferably, there is also a port 306, FIG. 7, in the tubular housing 270- which applies this same pressure to the annulus around the housing 270 below the lower packer 276.

For convenience, the upper zone ports 289 and 290 have been shown directly opposite the upper formation 26 and the lower zone ports 291 and 292 have been shown directly opposite the lower formation 28. If these zones are thick and/or widely separated, an extremely long slide valve 293 with a correspondingly long stroke would be required. Such a long slide valve and stroke can be avoided by providing passages, not shown, in the selector valve housing 270 for conveying the production from the upper and lower zones 26 and 28 to two closely spaced locations of relatively small vertical extents. This would permit a relatively short slide valve 293 and a relatively short over-all stroke, e.g., two or three feet.

In the event that removal of the selector valve 106 is required for any reason, the static return tubing pressure which acts on the lower end of the piston 286 to set the packers 274, 275 and 276 and the slips 271 must be released first. To accomplish this, a knockout bar, not shown, is lowered into the tubular slide valve 293 on a Wire line to break off a knockout plug 308, FIG. 7, shown as threaded into the piston 302 and extending into the interior of the slide valve, the broken portion of the knockout plug being caught by a removable strainer 315 at the lower end of the slide valve. The interior of the knockout plug 308 communicates with the space between the pistons 286 and 302 through a passage 309. Conse quently, when the knockout plug 308 is broken off, the static return tubing pressure acting on the lower end of the piston 286 is dissipated into the interior of the slide valve 293 and the inlet tubing 38 thereabove. This eliminates the upward packer-setting and slip-setting force on the piston 286, thereby releasing the slips 271 and the packers 274, 275 and 276.

As shown in FIG. 2 of the drawings, the upper end 294 of the slide valve 293 is provided with a head 310 engageable by a suitable fishing tool, not shown, on a wire line. (It will be understood that the fishing tool and the aforementioned knockout bar may be lowered into place simultaneously, rather than in two operations.) After the knockout plug 308 has been broken to release the slips 271 and the packers 274, 275 and 276, and the fishing tool has engaged the head 310 on the slide valve 293, an upward force on the wire line displaces the slide valve 293 upwardly until an annular flange 311, FIG. 5, on the slide valve engages lugs 312 connected to the respective slips 271. With this construction, the upward movement of the slide valve 293 causes the slips 271 to disengage the wall of the inlet tubing 38, upward movement of the lugs 312 relative to the tubular housing 270 being limited by engagement of the lugs with the upper ends of slots 313 through which they extend. When such disengagement of the slips 271 occurs, a continued upward pull on the slide valve 293 results in upward movement of the entire selector valve 106 through the inlet tubing 38 to the surface.

In installing the selector valve 106, it is preferably run in on a wire line by means of a fishing tool, not shown, adapted to fit over the upper end of the slide valve 293 and to engage a head 314, at the upper end of the selector valve housing 270, the selector valve being run in with the slide valve 293 in its lowermost, inoperative position. When the selector valve 106 has been lowered into its proper position in this manner, it is supported in such position by the wire line and fishing tool while the return tubing 54 is filled with liquid to develop the normal static return tubing pressure below the piston 286 through whichever control passage 258 or 261) happens to be open. This results in setting of the slips 271 and the packers 274, 275 and 276. Thereupon, the fishing tool may be released from the head 314 on the selector valve housing 270, and the fishing tool and wire line withdrawn from the inlet tubing 38. The selector valve 1116 is then ready for operation.

Control valve 130 The control valve 130 of the zone selector means 121 at the surface 24 is preferably similar to and operates in much the same manner as the bottom-hole control valve 102. More particularly, the programming means 140 preferably causes the control valve 136] to sequentially connect upper-zone and lower- zone control passages 322 and 324 to the supply line 142, in phase with the connection of the upper-zone and lower-zone control passages 25% and 260 to the return tubing 54 by the control valve 102. For a further description of the control valve 130 and the manner in which it operates, reference is made to my eo-pending application Ser. No. 429,- 573, filed Feb. 1, 1965, now Patent No. 3,326,290.

The upper-zone control passage 322 is connected to the upper-zone oil selector valve 132 and the upper-zone gas selector valve 138, while the lower-zone control passage 324 is connected to the lower-zone oil selector valve 134 and the lower-zone gas selector valve 138. This results in opening of the upper- zone selector valves 132 and 136 in phase with connecting the upper zone 26 to the inlet tubing 38, and results in opening of the lowerzone selector valves 134 and 138 in phase with connecting the lower zone 28 to the inlet tubing (except for a time delay imposed on the valves 132 and 134, as discussed in the next paragraph).

As shown in FIG. 1 of the drawings, time delay means or devices 326 and 328 are inserted in the control passages 322 and 324, respectively, ahead of the upper-zone and lower-zone oil selector valves 132 and 134, respectively. The time delay devices 326 and 328 are responsive to the pressure signals in the control passages 322 and 324, respectively, and serve to delay actuation of the oil selector valves 132 and .134, respectively, for a length of time suificient to purge the production tubing and the production line 150 of oil from the previously-produced formation 26 or 28, before connecting the line 150 to the oil handling equipment 122 or 124 corresponding to the zone to be produced next. This reduces intermingling of oil from the two zones to an absolute minimum when switching from one to the other, which is an important feature.

The selector valves 132, 13d, 136 and 138 are all identical so that only the selector valve 132 will be considered in detail.

Selector valve 132 Referring to FIG. 12 of the drawings, the selector valve 132 includes a valve body 330 inserted into the branch line 146 leading from the common production fluid line 159 to the oil handling equipment 122. The valve body 330 is provided therethrough with a passage 332 for the upper-zone oil, such pasage being encircled by an upstream-facing, annular valve seat 334. Engageable with the valve seat 334 is the head of a poppet valve 336 which is biased against the valve seat by the pressure of the incoming fluid. The stem of the poppet valve 336 carries a plunger 338 reciprocable in a cylinder 340, the

valve being biased toward its seat by a compression spring 342 in engagement with the plunger.

The lower side of the plunger 338 is exposed to atmospheric pressure through a vent 344, while the upper side of the plunger is exposed to the control pressure in the passage 324 leading from the control valve 130. Consequently, when the programming meansldt) directs the control valve 131 to connect the control passage 324- to the supply line 142, and restores-the normal operating pressure in the supply line downstream from the programming means, such pressure is applied to the upper side of the plunger 338. This pressure then overcomes the spring 342 and unseats the valve 336, thereby permitting oil production from the upper zone 26 to flow through the upper-zone oil selector valve 132 into the upper-zone oil handling equipment 122. When the programming means 140 directs the control valve to reduce the pressure in the control passage 324 to its minimum value, which may be zero, the spring 342 closes the upper-zone oil selector valve 132.

The lower-zone oil selector valve 134, the upper-zone gas selector valve 136 and the lower-zone gas selector valve 133 operate in the same manner as the upper-zone oil selector valve 132. Consequently, a further description is not necessary.

Summary of operation The operation of the various components of the well completion 2%) will be clear from the preceding description. Consequently, the over-all operation thereof will be summarized only briefly in this section, and only from the standpoint of switching production between the upper and lower zones 26 and 28.

The programming means first signals the control valve 102 to cause the selector valve 106 to open the inlet tubing 38 to the upper zone 26, and signals the control valve 130 to cause the upper- zone selector valves 132 and 136 to open. After a pre-set time interval, which may range from minutes or hours to days, the programming means 141) signals the con-trol valve 1&2 to cause the selector valve 106 to open the lower Zone 28 to the inlet tubing 38, and signals the control valve 130 to cause the lower- zone selector valves 134 and 138 to open. The selector valves 132 and 136 are opened in phase with the opening of the upper zone 26, and the selector valves 134 and 138 are opened in phase with the opening of the lower zone 28, except for the time delay provided by the time delay devices 326 and 323. Thus, the oil and gas produced by each formation are kept separate from the oil and gas produced by the other, which is an important feature. Also, excellent separation of the gas and oil produced by the respective zones 26 and 23 occurs in the U-tube 44, which is another important feature.

Although an exemplary embodiment of the invention has been disclosed herein for purposes of illustration, it will be understood that various changes, modifications and substitutions may be incorporated in such embodiment without departing from the spirit of the invention as defined by the claims which follow. It will also be understood that when an upper producing zone and a lower producing zone are referred to herein and in the claims which follow, they may be the only zones being produced, or they may be the uppermost and the lowermost, respectively, of any two of three or more zones being produced.

I claim as my invention:

1. A producing installation for a well drilled from the surface through an upper producing zone at least into a lower producing zone, including:

(a) a tubing system extending downwardly in the well at least into the lower producing zone; (b) said tubing system including an inlet tubing and a production tubing in side-by-side relation;

(c) means for providing fiuid communication between the upper zone and said inlet tubing at an upper level above the lower end of said tubing system;

((1) means for providing fluid communication between the lower zone and said inlet tubing at a lower level above the lower end of said tubing system;

(e) means interconnecting said inlet and production tubings adjacent the lower end of said tubing system and below said upper and lower levels;

(f) selector means for selectively placing the upper and lower zones in fluid communication with said inlet tubing;

(g) a fluid operated pump in said production tubing for pumping fluid from said inlet tubing upwardly through said production tubing to the surface;

(h) said tubing system including a supply tubing for delivering operating fluid under pressure to said p p;

(i) said selector means including fluid operated selector valve means in said inlet tubing for selectively placing the upper and lower zones in fluid communication with said inlet tubing; and

(j) said selector means including control valve means in said supply tubing and operable from the surface for operating said selector valve means.

2. A producing installation for a well drilled from the surface through an upper producing zone at least into a lower producing zone, including:

(a) a tubing system extending downwardly in the well at least into the lower producing zone;

(b) said tubing system including an inlet tubing and a production tubing in side-by-side relation;

(c) means for providing fluid communication between the upper zone and said inlet tubing at an upper level above the lower end of said tubing system;

(d) means for providing fluid communication between the lower zone and said inlet tubing at a lower level above the lower end of said tubing system;

(e) means interconnecting said inlet and production tubings adjacent the lower end of said tubing system and below said upper and lower levels;

(f) selector means for selectively placing the upper and lower zones in fluid communication with said inlet tubing;

(g) a fluid operated pump in said production tubing for pumping fluid from said inlet tubing upwardly through said production tubing to the surface; through said production tubing to the surface;

(h) said tubing system including a supply tubing for delivering operating fluid under pressure to said P p;

(i) said selector means including fluid operated selector Valve means in said inlet tubing for selectively placing the upper and lower zones in fluid communication with said inlet tubing;

(j) said selector means including fiuid operated control valve means in said supply tubing and responsive to fluid pressure variations in said supply tubing for operating said selector valve means; and

(1:) means at the surface for varying the fluid pressure in said supply tubing.

3. A producing installation for a well drilled from the surface through an upper producing zone at least into a lower producing zone, including:

(-a) a tubing system extending downwardly in the well at least into the lower producing zone;

(b) said tubing system including an inlet tubing and a production tubing in side-by-side relation;

(c) means for providing fluid communication between the upper zone and said inlet tubing at an upper level above the lower end of said tubing system;

(d) means for providing fluid communication between the lower zone and said inlet tubing at a lower level above the lower end of said tubing system;

(e) means interconnecting said inlet and production tubings adjacent the lower end of said tubing system and below said upper and lower levels;

(f) selector means for selectively placing the upper and lower zones in fluid communication with said inlet tubing;

(g) a fluid operated pump in said production tubing for pumping fluid from said inlet tubing upwardly through said production tubing to the surface;

(h) said tubing system including a supply tubing for delivering operating fluid under pressure to said p p;

(i) said selector means including fluid operated selector valve means in said inlet tubing for selectively placing the upper and lower zones in fluid communication wtih said inlet tubing;

(j) said selector valve means including .a selector valve movable vertically in said inlet tubing through a range of positions including upper-zone and lowerzone positions wherein it connects said inlet tubing to the upper and lower zones, respectively; and

(k) said selector means including fluid operated control valve means in said supply tubing, and responsive to fluid pressure variations in the supply tubing, for sequentially placing said selector valve in its said upper-zone and lower-zone positions.

4. A producing installation fora well drilled from the surface through an upper producing zone at least into a lower producing zone, including:

(a) a tubing system extending downwardly in the well at least into the lower producing zone;

(b) said tubing system including an inlet tubing and a production tubing in side-by-si de relation;

(0) means for providing fluid communication between the upper zone and said inlet tubing at an upper level above the lower end of said tubing system;

(d) means for providing fluid communication between the lower zone and said inlet tubing at a lower level above the lower end of said tubing system;

(e) means interconnecting said inlet and production tubings adjacent the lower end of said tubing system and below said upper and lower levels;

(if) selector means for selectively placing the upper and lower zones in fluid communication with said inlet tubing;

(g) a fluid operated pump in said production tubing for pumping fluid from said inlet tubing upwardly through said production tubing to the surface;

(h) said tubing system including a supply tubing for delivering operating fluid under pressure to said P p;

(i) said selector means including fluid operated selector valve means in said inlet tubing for selectively placing the upper and lower zones in fluid communication with said inlet tubing;

(j) said selector valve means including a selector valve movable vertically in said inlet tubing through a range of positions including upper-zone and lowerzone positions wherein it connects said inlet tubing to the upper and lower zones, respectively;

(k) said selector means including fluid operated control valve means in said supply tubing; and responsive to fluid pressure variations in the supply tubing, for sequentially placing said selector valve in its said upper-zone and lower-zone positions; and

(1) means at the surface for varying the fluid pressure in said supply tubing.

5. A producing installation for a well drilled from the surface through an upper producing zone at least into a lower producing zone, including:

(a) a tubing system extending downwardly in the well at least into the lower producing zone;

(b) said tubing system including an inlet tubing and a production tubing;

(c) means for providing fluid communication between the upper zone and said inlet tubing at an upper level above the lower end of said tubing system;

((1) means for providing fluid communication between the lower zone and said inlet tubing at a lower level above the lower end of said tubing system;

(e) means interconnecting said inlet and production tubings adjacent the lower end of said tubing system and below said upper and lower levels;

(f) selector means for selectively placing the upper and lower zones in fluid communication with said inlet tubing;

(g) a fluid operated pump in said production tubing for pumping fluid from said inlet tubing upwardly through said production tubing to the surface;

(h) said tubing system including a supply tubing for delivering operating fluid under pressure to said P p;

(i) said selector means including control valve means in and responsive to pressure variations in said supply tubing for causing said selector means to selectively place the upper and lower zones in fluid communication with said inlet tubing; and

(j) means at the surface for varying the pressure in said supply tubing.

6. A producing installation for a well drilled from the surface through an upper producing zone at least into a lower producing zone, including:

(a) a tubing system extending downwardly in the well at least into the lower producing zone;

(b) said tubing system including an inlet tubing and a production tubing; (c) means for providing fluid communication between the upper zone and said inlet tubing at an upper level above the lower end of said tubing system;

(d) means for providing fluid communication between the lower zone and said inlet tubing at a lower level above the lower end of said tubing system;

(e) means interconnecting said inlet and production tubings adjacent the lower end of said tubing system and below said upper and lower levels;

(f) first selector means for selectively placing the upper and lower zones in fluid communication with said inlet tubing;

(g) a fluid operated pump in said production tubing for pumping fluid from said inlet tubing upwardly through said production tubing to the surface;

(h) said tubing system including a supply tubing for delivering operating fluid under pressure to said p p;

(i) upper-zone and lower-zone handling facilities at the surface;

(j) second selector means operable in phase with said first selector means for selectively placing said production tubing in fluid communication with said upper-zone and lower-zone handling facilities;

(k) first and second control means responsive to fluid pressure variations in said supply tubing for operating said first and second selector means, respectively, in unison; and

(1) means at the surface for varying the fluid pressure in said supply tubing.

7. A producing installation for a well drilled from the surface through an upper producing Zone at least into a lower producing zone, including:

(a) an inlet tubing extending downwardly in the well at least into the lower producing zone;

. (b) means for providing fluid communication between said inlet tubing and the upper zone;

(c) means for providing fluid communication between said inlet tubing and the lower zone;

((1) fluid operated selector valve means in said inlet tubing for selectively placing the upper and lower zones in fluid communication with said inlet tubing;

(e) said selector valve means including a selector valve hydraulically movable upwardly from an inoperative position to lower-zone and upper-zone operating positions wherein it connects said inlet tubing to the upper and lower zones, respectively;

(f) said selector valve being movable downwardly into its inoperative position by gravity; and

(g) means for hydraulically moving said selector valve upwardly into its operating positions selectively.

8. A producing installation for a Well drilled downwardly from the surface into communication with different producing zones, including:

(a) a fluid operated pump in the Well and having a well fluid inlet;

(b) means including a supply tubing in the well for delivering operating fluid under pressure to said pump to operate same;

(c) means in the well, including selector valve means, for selectively placing the producing zones in fluid communication with said well fluid inlet;

(d) means in the well, including control valve means in communication with said supply tubing and responsive to variations in the pressure of the operating fluid therein, for actuating said selector valve means, said control valve means including a movable control valve, and including actuating means responsive to variations in the pressure of the operating fluid in said supply tubing for moving said control valve;

(e) means at the surface for producing variations in the pressure of the operating fluid in said supply tubing; and

(f) means in the well for conveying fluid discharged by said pump upwardly to the surface.

9. A producing installation according to claim 8 wherein said actuating means includes piston means reciprocable in response to variations in the pressure of the operating fluid in said supply tubing and includes ratchet means for converting movement of said piston means in one direction into movement of said control valve.

References Cited UNITED STATES PATENTS 2,822,757 2/1958 Coberly 1034 X 2,831,539 4/1958 En Dean et al. 2,403,987 7/1946 Lewis. 2,917,004 12/1959 Davis et al 103-4 X 2,951,536 9/1960 Garrett 16645 X 3,054,456 9/1962 Hammaker 16645 X 3,086,592 4/1963 Hoch 16667 X 3,115,187 12/1963 Brown. 3,172,469 3/1965 Coberly et al. 166-405 X CHARLES E. OCONNELL, Primary Examiner,

I, A. CALVERT, Assistant Examiner,

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,368,628 February 13, 1968 Clarence J. Coberly It is certified that error appears in the above identified patent and that said Letters Patent are hereby corrected as shown below:

Column 2, line 10, for "the" read that column 3, line 59, for "agent" read spent column 4, line 10, for "position" read positions column 6, line 18, for

"extend" read extends column 11, line 70, strike out '"the tubular housing 270 to set the slips in response to";

column 17, line 46, strike out "through said production tubing to the surface'% line 54,:for "fiuid" read fluid Signed and sealed this 24th day of June 1969.

6EAL) Attest:

WILLIAM E. SCHUYLER, JR.

Commissioner of Patents Edward M. Fletcher, Jr.

Attesting Officer

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