|Publication number||US3170520 A|
|Publication date||Feb 23, 1965|
|Filing date||Aug 28, 1962|
|Priority date||Aug 28, 1962|
|Publication number||US 3170520 A, US 3170520A, US-A-3170520, US3170520 A, US3170520A|
|Original Assignee||Reda Pump Company|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (8), Referenced by (25), Classifications (11)|
|External Links: USPTO, USPTO Assignment, Espacenet|
4 Sheets-Sheet 1 INVENTOR F w \E, H N m m w M a i? a m U 25m 5 MH FZJ VwEMWWw M M H 1 7w n s 60 IF A F Fu M E m R 2 a A Z ATTORNEY Feb. 23, 1965 A. ARUTUNOFF DUAL-FLOW TRANSFER ASSEMBLY Filed Aug. 28, 1962 1965 A. ARUTUNOFF 3,170,520
DUAL-FLOW TRANSFER ASSEMBLY Filed Aug. 28, 1962 4 Sheets-Sheet 3 ATTORNEY A. ARUTUNOFF DUAL-FLOW TRANSFER ASSEMBLY Feb. 23, 1965 Filed Aug. 28, 1962 4 Sheets-Sheet 4 United States Patent 3,170,520 'yDUAL-FLOW TRANSFER ASSEMBLY 'Armai's Arutunolf, Bartlesville, Okla.,'assignor to Reda,
This invention relates to oil producing equipment of the type embodying a well casing which extends through and communicates with separate producing zones through suitable perforations in the casing, separate pumping mechanisms being employed for simultaneously delivering fluid from the respective zones. More particularly, the invention consists in new and useful improvements in a dual-flow transfer assembly adapted for use in connection with said producing equipment and designed to seal the well casing between the two pump mechanisms and, at the same time, to isolate the fluid produced from the separate zones and direct its flow to separate points of delivery In operations of this character, the fluid from the uppermost zone is usually delivered by a rod actuated plunger type pump located above the upper Zone, and the fluid from the lower zone is produced by a separate submergible electric pump and motor unit located in the lower portion of the casing In orderto maintain the isolation of the fluids produced from the upper and lower zones, all of which enters through respective perforations in the main casing, it is necessary to seal the casing above the upper zone and provide means for simultaneously'conducting to the'surface, the fluids produced from the respective zones through entirely separate'passageways within the casing.-
- It is therefore the primary object of the present invention to provide a dual flow transfer assembly adapted to divert fluid being discharged through the tubing connected to the lower pump, to the annular passageway surrounding the tubing containing the upper pump, and to 'simul- 'taneously divert the fluid entering the casing from the upper zone to the central tubing connected to the upper pump.
In equipment of this type which requires the lowering of a cable to the motor of the submergible pump, the handling and disposition'of the cable have been a considerable problem because of the pressure diiferentials encountered and the necessity of cutting and splicing the cable during installation, It is therefore another object of the invention to provide an assembly such as referred to, having novel means for accommodating the cable regardless of the vertical location of the transfer assembly and without the necessity of cutting the cable during installation or if the location of the transfer assembly requires a change.
Another object of the invention is to provide a flow transfer assembly which is not only adapted for use in the dual' completion of a well, but which may be used with equal effect when it is desired to withdraw fluid from av into the well and also serves the added purpose of divert- In some instances, the vertical distance between twoproducing zones is insufiicient to accommodate the length 3,176,52 Patented Feb, 23, 1965 of the submergible motor and pump assembly required for delivering fluid from-the lower zone. It is' therefore a further object of this invention to provide means for adapting the assembly for use in separately delivering fluids from relatively close upper and lower producing zones, and, at the same time, to accommodate the length of the conventional submergible electric motor and pump unit.
Naturally, when the fluids from two separate producing zones are to be delivered to the surface separately,- it is necessary to employ two pumping systems, and with conventional equipment, the lowering of the separate pumping systemssinto a well casing and the relationship of the two systems in the well casing present something of a problem. It is therefore another object of the invention to accomplish this separate-delivery of fluids from two producing zones in a practical and economical manner utilizing conventional tubing and concentrically arranged elements supported by the tubing, which greatly facilitates installation and removal of the apparatus and requires a minimum of maintenance.
With the above and other objects in view which will appear as the description proceeds, the invention consists in the novel features herein set forth, illustrated in the accompanying drawings and more particularly pointed out in the appended claims.
Referring to the drawings in which numerals of like character designate similar parts throughout the several views:
FIGURES 1A and 1B jointly illustrate an installation embodying the present invention for separately delivering to the surface, fluids from upper and lower producing zones;
FIGURE 2 is an enlarged vertical sectional View of the dual-flow transfer unit; 3
FIGURE 3 is a topplan view of the assembled unit shown in FIGURE 2; i t 7 FIGURE 4 is an exploded top plan view of the same; FIGURE 5 is a vertical sectional view taken on line 5-,5 of FIGURE 3;
FIGURE 6 is a similar view taken on line 6-6 of FIGURE 3;
FIGURE 7 is a view generally similar to FIGURES 1A and 1B, illustrating the modification of the assembly adapted for use in connection with the separate delivery of fluids from two relatively close producing zones; and
FIGURES 8A and 8B jointly illustrate an installation embodying the flow transfer unit of the presentinvention for the rte-introduction of fluid produced in a lower zone into an upper zone.
In the drawings, referring first to FIGURES 1A and 1B, the usual well casing 10 extends from the surface into a drilled well and communicates with upper and lower producing zones 11 and 12 respectively, through suitable perforations 11a and 12a in the wall of the casing. A delivery tube 13 at the upper end of the casing 10 is connected at the surface to a suitable reservoir or distribution system (not shown) and concentrically supports a conventional rod-actuated plunger-type pump 14,
the lower end of which is connected to the central passageway of the flow-transfer unit 15 of the present invention which will be described in detail later on. The unit 15 concentrically supports a string of tubing 16 from the lower end of which is suspended a conventional submergible electric motor and pump assembly comprising a centrifugal pump 17 having radial inlets 18, a motor protecting unit 19 and an electric motor 20, all conccntri-cally connected in the usual manner.
A conventional expandible anchor device 22 comprising a combination of anchor and packer means is provided at the lower extremity of the installation for engagement with the casing to prevent theup and down movement of motor-pump assembly due to up and down movement of the rod of pump 14, and at a suitable point between the upper and lower producing zones 11 and 12, thel'tubing 16 is provided with a packer 23'which seals theperiph-- ings, thesubmergible motor and pump assembly 1720 is arranged in spaced. relation to the inner periphery of the casingv It), thus providing an annulus 25 surrounding the central tubular passageway formed by the de'livcry tube 13, the rod actuated pump 14 and the string of tubing 16. The annulus 25-is sealed by the packer 23 which thereby isolates the fluids entering the casing It? from the upper and lower zones 11 and 12. The area of the casing lit above the packer 23 forms an annular passageway 25a surrounding the tubing 16 and communicates with the upper zone 11 through perforations llaand the upper end of passageway 25a is sealed around the flow transfer unit by packing rings 15a surrounding the upper portion,
of unit 15, as will be later described, thereby providing a combined transfer unit and packer.
Thus, the packing rings 15a further separate I the annulus 25 into another annular passageway 25b surrounding the delivery tube 13 and plunger-type pump 14, said last-named passageway leading to the surface where it is connected to a separatereceiving means or distribution system (not shown). Likewise, the central passageway formed by the tubing is divided into two sections by the transfer assemblylS, the first section 26 terminating at the upper end of the tubing 16, and the other section 26a comprising the cylinder or pump 14 and the delivery tube 13 above the transfer unit 15,
The flow transfer unit per se will be best understood by reference to FIGURES 2 to 6 inclusive, where it will be seen that the unit comprises a main body 27 which is cylindrical in form' and provided with an upper central longitudinal ,bore 28 internally threaded at its upper extrernity as at 22 to receive the lower end of the'cylinder of the upper pump 14, the latter including the usual ball valve or the like, 3%. The lower end of the bore 28 is closed within the body 27 and the interior of the bore communicates With the exterior of the body 27 through a series of radial ports 32. As will be seen from FIGURE.
1A, the outer periphery ofthe body 27 of unit 15 is spaced inwardly from the, inner walls of the casing 10, thereby establishing communication of the annular passageway 25a with the upper central bore 28 through ports The lower end of the body 27 is provided with a short lower vertical bore 33 which is concentric with bore 28 and internally threaded as at 34 to receive the complementary threads of the tubing 16. The lower bore 33 comfrom the lower zone 12 is drawn by the submergible pump 17 from-which it is discharged centrally through the tubing 16, said annulus 25 being sealed below the upper zone 11 by the packer 23 as previously explained, to isolate the fluids from the tube producing zones. Above the packer 23, the annular passageway 25a surrounding unit 15, receives the fluid from the upper zone 11 through the perforations 11a, and from the passageway 25a, the upper zone fluid enters the upper central bore 28 of unit 15 surface.
through radial ports 32-under the influences of the plunger type pump 14 which; delivers it through tubing 13 tolthel Simultaneously, the fluid from the lower zone 12 being pumped by submergible pump 17, passes through the lower section of tubing 16, through the packer 23 and into the vertical channels 35 of the unit 15 through ducts 36, and thence int'o'the upperannularpassageway 25b,
from whence'it is delivered to the surface. In other words, the fluid from the-lower zone is first introduced into the casing and conductedthrough an annular passageway to the pump 17 which'discharges it centrally to the flow transfer unit 15,'which, in turn, diverts the fluid to the upper annular passageway 25b, while the fluid from the upper zone is also introduced into the easing into an annular passageway 25a which delivers it to the transfer unit 15 through the radial ports therein, Where it is'diverted to the central discharge tube of pump'l i. During this entire operation, it will be seen that by diverting the flow of fluids from the separate zonesgas described, they remain isolated from one another and are, separately delivered to the surface. 1 V L In this connection, it may be stated that the described isolation of the fluids from the two separate zones is portant when the two zones are producing fluids of differ;
ent character and gravity, the mixture of which is unde-r sirable, and it is also desirable for facilitating the control of the. volume of production from the respective zones,
Returning to the specific structure of the flow transfer device 15 as illustrated in FIGURES 2 to' 6, and with particular reference to FIGURE 2, it'will be seen that the upper portion of the periphery of the body 27 is'recessed as at 37 to accommodate preferablyapair of an nular rubber packing rings 15a shown in FIGURE 1A;-
Obviously, these packing rings 1511 close the u per portion of the lower annular passageway 25a and pie vent the fluid therein from passing into the upper annular passageway 25b, so as to insure itsentry into the radial ports 32 leading to the upper central bore 28 in the body 27.
As previously stated, the flow transfer 15 is de-'. signed to accommodate an electric cable leading to the.
submersible electric motor 20. As best seen in FIGURE$ 3 and 4,-this is accomplished by providing a removable. portion27a, longitudinally separated from the main body" 27 along a line 27b which forms a chord with respect to the circumference of'the cylindrical body'2'7; Longs tudinally extending grooves 38 are formed-in the re'spec tive sections 27 and 27a which, when the sections are bolted together by suitable bolts 39, jointly form a' bore to receive the cable 24. A- split packing'gla'nd fits in the upper end of the bore 38 to prevent leakage of fluid" through the passageway. This gland is made in two pieces as seen in FIGURE 4, jointly forming'a depending annular sleeve 40a which, after being applied .to opposite sides of the cable, fits. into the slightly enlarged opening at the upper .end of the joined grooves 38 and is held in' sealing engagement with the cable by the pressure applied to the bolts 39 which secure the two sections of the body 27 together. The upper extremities of the sleeve sections 40a terminate .in complementary flange members 40badapted to diagonally overlie the junction 27b of the rnain and separable portions of. the body27. Diagonally opposed apertures 41, are provided in the adjacent end faces is split longitudinally at spaced points around its periphery to provide a removable section 23a secured in place by bolts 23b to accommodate that portion of the cable 24- which extends below the flow transfer unit 15, the separable parts of the packer 23 being provided with coacting:
grooves in a mannersimilar to grooves 38 in the unit 15.
The packer 23 is preferably of the type which includes a split packer cup 23c, the lower portion of whichis tapered to fit in a suitable recess (not shown) in the packer body and is held in wedging engagement with the interior thereof, by -a complementary split adaptor 23d. Thus, upon removal of the split section 234, the split cup and split adaptor may be removed and replaced after the cable 24 is installed.
As previously explained, in some instances the upper and lower producing zones are vertically spaced in a relatively short distance which is insuflicient to accommodate the length of the pump, protector and motor assembly 17, 19 and 20, and in such a situation the embodiment of the invention illustrated in FIGURE 7 is employed. Here it will be seen that the assembly'functions much in the same manner as that just described, with the exception that an auxiliary casing 43 houses the submergi-ble pump and motor assembly and is suspended by threaded connection from the lower extremity of the flow transfer unit 15.
The auxiliary casing 43 is spaced inwardly from the outer casing 10 and as in the embodiment shown in FIGS. 1a and 1b,in order to properly isolate the two zones 11 and 12, the surrounding passageway 48 is provided with any suitable packing48a at a point between zones 11 and 12. This casing 43 is alsoradi-ally spaced outwardly from the pump and motor assembly 17-20, its lower extremity having a reduced neck 45 which extends through the anchor device 22 and terminating in an open inlet end 46 which communicates with the interior of the outer casing 10 adjacent the perforations 12a in the vicinity of the lower producing zone 12. Thus, the interior of the auxiliary casing 43 provides an annular passageway 47 fed from the inlet 46, which, under the force of the submergible pump 17, delivers fluid from the lower zone 12 to the central tube 16, and thence to the radially offset channels 35 in the flow transfer unit which in turn deliver the fluid to the upper annular passageway 25b which conducts it to the surface collection or distribution point. Similarly, the auxiliary casing 43, together with the outer casing 10, provides an outer concentric annular passageway 48 which communicates with the upper pro-.
ducing zone 11 through perforations 11a. This outer passageway 48 delivers the fluid from zone 11 through the radial ports 32 and into the upper central bore 28 of the flow transfer unit 15, from whence it is delivered under the action of the upper pump 14, to a separate collection or distribution point.
With this arrangement, it will be seen that the auxiliary casing 43 coacts with the outer casing 10 to compensate for the reduced vertical spacing of the producing zones 11 and 12, and, at the same time, to effect isolation of the fluids produced from these separate zones.
While the flow transfer unit of the present invention is primarily designed for use in the dual completion of wells by the separate delivery and isolation of the fluids produced fromupper and lower producing zones, it may also be effectively used where it is desired to re-introduce fluid produced from a lower zone, for example, into the strata of an upper zone for the purpose of supplementing the pressure in the upper zone, such as by water flooding, to facilitate production from an adjacent well. Such an adaptation of the invention is shown in FIGURES 8A and 8B where it will be seen that installation is substantially the same as that shown in FIGURES 1A and 1B with the exception that instead of providing a packer 23 below the flow transfer unit 15 as in FIGURE 1A, a packer 31 is installed above the flow transfer unit 15 to seal the casing 10 above the upper zone 11. Also, there being no need for a second pump such as 14 in FIGURE 1A, a supporting tube 49 extends from the surface-through packer 31 with its lower end connected to and suspending the flow transfer unit 15 and string of tubing 16.
In this re-injection operation, the fluid from the lower zone 12 enters annulus 25 in casing 10 through per forations 12a and is drawn into the submergible pump 17 through inlets 18. The pump 17 forces the fluid upwardly through tubing 16 until it reaches the flow transfer unit 15 where it is diverted from the central tube through ducts 36 and vertical offset channels 35 for introduction into the annular passageway 2512. This passageway being sealed above the upper producing zone 11 by packer 31, the fluid introduced into passageway 25b is forced under the pressure of pump 17 into the upper zone-11 through perforations 11a, thus supplementing the pressure of the upper zone to facilitate production by adjacent wells.
In the re-injection installation just described, the centralbore 28 and connectingradial ports 32 in the flow transfer unit 15 perform no function insofar as the diversion of fluid is concerned, but they in no way hinder that operation. In fact, they can serve a useful purpose in facilitating the observation of the fluid level in the central tube 49 which is connected to bore 28, and thus coma municates with the casing 10 below the transfer unit ,15. It will thus be apparent that a standard dual flow transfer unit such as embodied in the present invention is adaptable without change to various types of installations.
From the foregoing, it is believed that theinvention may be readily understood by those skilled in the art without further description, it being borne in mind that numerous changes may be made in the details disclosed without departing from the spirit of the invention as set forth in the following claims.
1. A dual-flow transfer unit for isolating and separate- 1y directing the flow of fluids fed from separate producing zones into a common well casing, comprisng a cylindrical body insertible in concentric spaced relation in said casing, an upper central longitudinal bore in said body, at least one radial inlet port placing said upper bore in communication with the annular area in said casing surrounding said body, a central discharge opening at the upper end of said upper bore connected to a central discharge tube extending upwardly through said casing, peripheral sealing means on said body above said inlet port isolating said annular area from the upper portion of said casing, at least one longitudinally extending, laterally offset channel in said body, discharging at its upper end into said isolated upper area of the casing, a lower central longitudinal bore in said body, a duct connecting said last-named bore to the lower end of said channel, and a central inlet tube connected into said lower bore, whereby fluids fed centrally through said lower bore are diverted laterally and discharged through the upper area of said casing, and fluids fed from the annular area surrounding the periphery of said body through said radial inlet port, are diverted axially and discharged through said central discharge tube, said body being divided longitudinally into separable sections, the abutting faces of which are provided with complementary recesses which, when as! sembled, jointly form a common cable receiving bore.
2. A transfer device as claimed in claim 1, including a separable gland insertable in one end of said cable bore for sealing a cable extending through the latter, and means for securing said gland to respective separable sections.
3. ,A device as claimed in claim 1, including a gland for sealing a cable extending through said cable bore, said gland comprising a cylindrical central sleeve adapted to fit in said cable bore, a flange integral with said sleeve adapted to overlie the junction of said separable sections, and having diagonally opposed apertures respectively gvfrlying said separable sections for receiving securing 4. In a well casing having a string of tubing, an electrically driven submergible pump operatively connected to said tubing, a cable leading from an external source of power to said pump, a cable accommodating packer assembly adapted for selective location in said casing, said assembly comprising a cylindrical body having a separable, parti-cylindrical portion an open cable receiving end of said bore'for sealing a cable extending through the latter, and means for securing said gland torespective body portions. p
5." A dual-flow transfer assembly for isolating and separately delivering fluids'fed from relatively closely spaced upper and lower producing zones intoa common well casing, perforated to communicate with respective zones, said assembly comprising acylindrical transfer body insertable in said-well casing, an'auxiliary' casing concentrically suspended from the lower end of said body said; bodyand said auxiliary casing being concentrically spaced from said well casing to provide a first annnularpassageway communicating with said upper zone, an upper central tube concentrically connected to the upper end of said body in spaced relation to said well casing to provide a second annular passageway, means sealing said well casing between said passageways, a lower central tube connected to the lower end of said body and spaced inwardly from said auxiliary casing, said auxiliary casing being open at its lower extremity for communication with said lower zone through said well casing, an upper pump connected to 'said upper central tube, a lower pump disposed in said auxiliary casing and connected to the lower central tube with its intake communicating with the interior of said auxiliary casing, and separate ducts inisaid transfer body respectively connecting said upper" central 7 tube to said first annular passageway and said-lower central tube to said second annular passageway, whereby, fluid pumped from said upper zone into said first annular passageway is diverted for delivery through said upper central tube and fluid pumped .from said lower zone into said .lower centraltube,throughsaid auxiliary casing, is diverted for. delivery through said second annular pas- Sageway. l
ReferencesCitedby the Examiner p I UNITED STATES PATENTS 6 2,242,166 5/41 Bennett 166-106 X 2,274,407 2/42 Hammer 166-45 2,368,428 1/45 Saurenman j 16645 2,717,041 9/55 Brown" 166-45 2,736,381, 2/56 Allen- 166-9 2,766,831 10/56 Otis 166-45 2,822,757 1 2/58 Coberly 103-46 3,064,580 11/62 Calvert et al. 103-4 CHARLES E; ocoNN'ELL; Primary Examiner.
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|U.S. Classification||166/65.1, 166/115, 166/313, 417/201, 166/185, 166/189, 166/106|
|International Classification||E21B43/14, E21B43/00|