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Publication numberUS2986216 A
Publication typeGrant
Publication dateMay 30, 1961
Filing dateDec 16, 1957
Priority dateDec 16, 1957
Publication numberUS 2986216 A, US 2986216A, US-A-2986216, US2986216 A, US2986216A
InventorsMcculloch Thomas B
Original AssigneeJersey Prod Res Co
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Apparatus for use in wells completed in a plurality of zones
US 2986216 A
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Description  (OCR text may contain errors)

May 30,1961 r. B. Mo'cuLLocH 2,936,215

APPARATUS FOR USE 1N WELLS COMPLETED 1N A PLURALITY oF zoNEs Filed Dec. 16, 1957 5 Sheets-Sheet 1 APPARATUS FOR USE IN WELLS COMPLETED 1N A PLURALITY oF zoNEs May 30, 1961 1'. B. MccuLLocH 5 Sheets-Sheet 2 Filed DBC. 16, 1957 FIG .6A

INVENTOR.

May 30, 1961 T. B. MccuLLocH y 2,936,216'

APPARATUS FOR USE IN WELLS COMPLETED IN A PLURALITY OF ZONES l Filed Dec. 1e. 1957 s sheets-sheet s INVENTOR.

Unite States Patent Gf APPARATUS FOR USE IN WELLS COMPLETED IN A PLURALITY OF ZONES Thomas B. McCulloch, Houston, Tex., assignor, by mesne assignments, to Jersey Production Research Company, Tulsa, Okla., a corporation of Delaware Filed Dec. 16, 1957, Ser. No. 702,852

8 Claims. (Cl. 166J114) The present invention is directed to apparatus for producing hydrocarbons. More particularly, the invention is directed to apparatus for producing hydrocarbons from vertically spaced apart productive zones. In its more specific aspects, the present invention has to do with apparatus which is placed once in the lifetime of the well and may be manipulated to produce hydrocarbons from a plurality of zones and to allow workover operations.

The present invention may be brietly described as apparatus for producing hydrocarbons from vertically spaced apart productive horizons penetrated by a Well bore having a casing arranged therein perforated in upper and lower zones. A tubing is arranged in the casing with its lower open end permanently placed above the upper of the zones. A mandrel is attached to and forms the lower end of the tubing, the mandrel having an internal diameter greater than the internal diameter of the tubing. A first packer is arranged on the mandrel adjacent its lower end and closing the casing-tubing annulus. A second packer is arranged below the lower end of the mandrel between the upper and the lower zones and serves to separate these two zones. The second packer has an open bore. A tubular member having an internal diameter substantially the same as the tubing is Slidably arranged in the mandrel. The tubular member is provided with sealing means on its lower end for placement in the open bore of the second packer. The tubular member has a length at least co-extensive with the mandrel and a sufficient length to extend at least to the second packer. Means are provided for moving the tubular member from a iirst position in the mandrel to a second extended position whereby the lower end of the tubular member is sealingly arranged in the open bore of the second packer. A first flow path is thus provided through the tubular member and tubing in the lower zone to the earths surface. A second flow path is also provided from the upper zone to the earths surface and may include a port in the mandrel above the rst packer or may be a second tubing string arranged with its lower open end above the upper of the plurality of zones.

The present invention will be further illustrated by reference to the drawing in which:

Figs. l and 2 illustrate two positions of the apparatus of the present invention;

Figs. 3,l 4, 5 and 6 represent various positions of a modication of the apparatus of Figs. l and 2;

Fig. 6a is an enlarged view of the springs shown in the drawing and illustrating the mounting thereof;

Fig. 7 illustrates another modication of the present invention; and

Figs. 8 and 9 show still another modification of the present invention.

Referring now to the drawing in which identical numerals will be employed to designate identical parts, numeral 11 designates a well casing which has been placed in a well bore 12 and which has been cemented 2,986,216 Patented May 30, 1961 in place in cement -13 and perforated in an upper `zone '14 with perforations 15 and in a lower zone 16 with perforations 17. Atubing 18 is arranged in the casing 11 and has attached to it by means of pipe connecting means l19 a mandrel 2l) which has a diameter greater than the diameter of the tubing 18. The mandrel 20 forms part of the tubing 18. A packer 21 is arranged on the mandrel 20 and serves to close the casing-tubing annulus 22. A second packer 23 is arranged below the lower end 24 of the mandrel 20 and separates 'the upper -zone 14 from the lower zone 16. Slidably arranged within the mandrel 20 is an elongated tubular member 25 which is formed on its upper end to provide a piston 26 having a sealing member such as a sealing ring 27 to form a seal with the internal wall of the mandrel 20. The mandrel 20 is provided with a sealing means 28 provided with a sealing ring 29 on its lower end which seals with the outer wall of the tubular member 25. A stop member 30 is provided on the inner wall of the mandrel 20 above the packer 21, the inner wall of the mandrel 20 also being provided with at least a port 3-1 which is above the packer 21 and serves to communicate the bore of the mandrel 20 with the tubing-casing annulus 22.

It is to be noted that the internal diameter of the tubular member 25 is substantially the same as the internal diameter of the tubing 18 and allows the free passage of well tools such as a shaped charge or bullet gun perforator 9 attached to a Wire line or cable l10 through the tubing 18 and the tubular member 25.

It is to be noted that the lowerV end of the tubular member 25 is provided with a sealing member 312 hav ing a sealing means such as ring 33. The sealing member 32 and sealing ring 33 are adapted to sealingly engage with the wall of bore 34 of packer 23 as will be described further hereinafter.

Referring now to Fig. 2, it will be seen that the tubular lmember 2S is shown in its maximum extended position with the sealing member 32 and sealing ring 33 engaged with the bore 34 to form a seal therewith.

By virtue of an arrangement as shown with respect to Fig. l, it is possible to produce simultaneously from the upper zone 14 and from the lower zone 16, production tluids moving up through the passageway 35 comprised of tubular member 25, the mandrel 20, and the tubing 18 to the earths surface.

In Figs. 3 to 6, inclusive, the mandrel 2S is provided with a helical coil spring 25a arranged embracingly thereon and bearing with its upper end against piston 26 and with its lower end against stop 30. In the position of Fig. 3, simultaneous production from zones 14 and 16 may be had through the tubing 18.

When it is desirable to plug oi the upper zone 14 the lower zone may be isolated by placing a plug such as 38 in the bore of packer 23 and cement pumped in by way of tubing 18 and tubular member 25. Excess cement may be washed out of the space 36 by extending the tubular member 25 as shown in Fig. `4 by applying iluid pressure against the upper side of pistonphead 26. In this position the sealing means 32 has moved out of the mandrel 20 thus allowing the washing-out uids to be circulated down the tubing 18, the tubular memberr25 through the annulus 37, out the port 31 and up the casingtubing annulus 22. It will be understood that this circulation may be reversed if desired. The tubular member 2S may be secured or latched in its various posi- Vtions by means such as latch springs 6! positioned with- Itubular member may extend to the position shown in Fig. 5. ln this position production fluid from zone 14 can flow into the space 36 up the annulus 37 through port 31 and casing annulus 22 to the earths surface, while production from zone 16 can ow through tubular member 25, mandrel 20' and tubing 18 to the earths surface.

Fig. 6 illustrates the tubular member in its lowermost extended position. This position, as are the previously mentioned positions, is accomplished by exerting fluid pressure down the tubing 18 against the piston head 26. With the apparatus in this position it is possible to work over the lower zone 16 with the workover fluid circulating down through tubing 1S, mandrel 20', tubular extension 25 and up through the bore 34 of packer 23, space 36, mandrel passage 37, port 31 and up the casing annulus 22 to the earths surface. This liuid circuit may be reversed if desired.

Referring now to Fig. 6a, it will be clear that springs 60 are arranged in recesses 60a of mandrel 20' such that on exertion of pressure by piston 26 against springs 60, they atten and move slidably in recesses 60a. Thus, when it is desired to return the member 25 from the position shown in Fig. 5 or 6 with the bore 34 partially or completely closed to the position shown in Fig. 3 or 4, iiuid pressure exerted against the underside of piston 26 through port 31 causes release from springs 60 and spring 25a then returns the member 25 to its rst position.

The tubular member 25 of Figs. 3 to 6 is returned to its retracted position by the force of the spring 25a and sufficient uid pressure exerted down the annulus 22 through port 31 against the underside of the piston head 26. This total pressure overcomes springs 60 and returns the tubular member 25 to its retracted position as shown in Figs. 3 and 4. The tubular member 25 is maintained in its extended position by virtue of the fact that the force of the spring 25a is in itself insuicient to overcome the springs 60. Thus, the springs 60 positively maintain the tubular member 25 in extended position, the tubular member 25 being extended byexerting suicient fluid pressure against the upper side of the piston head 26 to overcome the combined force of springs 60 and spring 25a.

It will be seen that the apparatus of the present invention as described with respect to Figs. l to 6 is exceedingly versatile, advantageous and useful in workover of both upper and lower zones and in the production of hydrocarbons and the like such as oil and gas from the upper and lower zones simultaneously. The present invention, as exemplified by Figs. l to 6, does not require the use of wire line tools and can be employed with the tubing permanently arranged in place and also with the tubular member slidably and permanently arranged in the mandrel.

Referring now to Figs. 7, 8 and 9, another embodiment of the present invention will be described. In this embodiment of the present invention a plurality of tubing strings is arranged in the well casing 11 as shown with respect to Figs. 4, 5 and 6. The embodiment of Fig. 7 is identical to Figs. l, 2 and 3 with the exception that a second tubing string 40 is arranged in a modied packer 41 with its lower open end 42 above the zones 14 and 16. The modified packer 41 closes th'e annulus 22 between the mandrel 20 and the casing 11, as Well as the annulus between the tubing 40 and the casing 11.

The embodiment of Fig. 7 is shown arranged with the tubular member 25 in its extended position with the sealing means 32 and sealing ring 33 in the bore 34 of packer 23 to provide communication with the zones 14 and 16 through perforations 15 and 17, respectively. By allowing the flow from lower zone 16 to proceed through the tubular member 25 and upwardly through the mandel 20 and tubing 18 it is possible to obtain production from the zone 16 simultaneously with production from the upper zone 14, the ow being through the 4 perforations 15 into the space 36 and then through the tubing 40 to the earths surface.

Workover operations may be conducted with the embodiment of Fig. 7 similarly with respect to Figs. 1 to 6 with the exception that the tubing 40 will be used as a separate ow path to the earths surface rather than the casing-tubing annulus 22 as described with respect to Figs. l, 2, and 3.

The embodiments of Figs. 8 and 9 are similar to the embodiments of Figs. 1 to 6 with the exception that in this embodiment the tubing 18 and 40 are both provided with mandrels 20 forming the lower end thereof having tubular members 25 arranged Within the mandrels 20. As shown with respect to Fig. 8, worltover operations may be conducted by having the tubular members 25 in their extended position in a modied packer 50, sealingly arranged therein by the sealing members 32 and sealing rings 33. It is to be noted that the left hand tubular member 25 extends substantially below the packer 50 into the zone 16. This allows workover fluid to be introduced down through the tubing 18, mandrel 20, and tubular member 25 on the left hand side with the workover fluids proceeding upwardly through the right hand tubular member 25, mandrel 20 and tubing 40.

In order to obtain production with the assembly of Figs. 8 and 9, the tubular members 25 of Fig. 9 are shown, one in the extended position and the other in the retracted position. For example, the right hand tubular member 25 is shown retracted into its respective mandrel 20 while the left hand tubular member 25 is extended from the mandrel 20 and is sealingly arranged in the packer 50 as described with respect to Fig. 7, the bore 51 of the packer 50 being closed by a retrievable plug member 38 with a sealing ring 39 such as described with respect to Fig. 1, the bore 52 of the packer 50 being closed with the tubular member 25 on the left hand side to allow production from the lower zone while production from the upper zone proceeds through the perforations 15 and thence upwardly through the right hand tubular member 25 and the tubing 40 to thc earth's surface as has been described.

It is to be noted with respect to the embodiments of Figs. 7 to 9 the second tubing 40 in either of the embodiments serves as a path of ow such as the casing-tubing annulus of Figs. l to 3, with workover and production operations being conducted as has been described.

Packers 21, 23, 41, and 50 are described in the literature and are of the type shown in The Composite Catalog of Oil Field and Pipe Line Equipment, 21st edition (1955-56), copyright 1955, The Gulf Publishing Co., Houston, Texas. On page 849 of The Composite Catalog supra there is described a dual string packer and the operation thereof which may be employed as packers 41 and 50. On pages 850 and 851 of the The Composite Catalog supra a Brown Duo-Pak packer is described along with the operation thereof which may be employed as packer 23. Pages 537 to 539 of The Composite Catalog supra provide a description of a Baker Retainer Production packer suitable for use as packer 23. The operation of said Baker packer is also described at pages 537 to 539 of The Composite Catalog supra.

The plug member 38 may be a plug lowerabe through a tubing for expanding in a bore larger than the tubing such as of the type described in the patents to Rumble 2,781,- 852, Rumble et al. 2,781,853, and to Huber 2,831,540.

While the present invention has been illustrated as showing a fluid pressure operated means for moving the tubular members 25 from their first position retracted in the mandrel 20 to an extended position out of the mandrel 20, other means may be used such as have been described in Serial No. 594,627, entitled Permanent Well Completion and filed June 28, 1956, in the name of the instant inventor. Such means may include a wire line lowerable and retrievable restriction means for restricting the passageway through the tubular member 25 on application of fluid pressure thereagainst. Also, such means may include a wire line tool such as has been described in Serial No. 430,101, entitled Extension of Effective Length of Tubing and filed May 17, 1954, for the instant inventor, including a grab tool for engaging with the tubular member 25 for moving same from a first to a second position.

ln conducting cementing operations in either the upper zone 14 or the lower zone 16, it is preferred to use a low strength, low water loss cement such as described in the patent toSalathiel, U.S. 2,582,459. However, while the Salathiel cement may be preferred, other commercially available low strength,` low water loss cements may be used. For example, oil-emulsion cements and the like may also be employed in cementing operations using the apparatus of the present invention.

The apparatus of the present invention may be used in workover and servicing operations such as involving acidizing, gun perforating, cementing operations, in production of hydrocarbons, in well stimulating and any of the many operations which are conducted with respect to well completion, recompletion, servicing operations, as well as production simultaneously and separately from a plurality of vertically spaced apart hydrocarbon productive horizons.

The present invention is of considerable utility and is quite advantageous inasmuch as heretofore in conducting operations such as has been described herein, it has been necessary to lower a retrievable production tube through the tubing to extend to a second packer below the lower open end of the tubing. In the present invention the tubing is permanently arranged in place with a slidable member arranged in a mandrel of greater diameter than the tubing such that the slidable member may be positionedv either by pressure or by other means to extend to the lower packer and to allow `production simultaneously and separately from the two horizons, zones, strata, and the like of a well bore. Another advantage of the present invention is that the tubular member slidably arranged in the mandrel provides a full opening bore through which perforators, either gun, shaped charge, chemical, or mechanical, may be lowered therethrough to be operated between the spaced apart packers or below the lower of the packers for obtaining production from a different level than had been obtained prior to the servicing operations. Provision of the full opening bore is quite advantageous. In short, the present invention allows workover operations in the upper and in the lower zone through the tubing and tubular member without manipulation of the tubing or the tubular member excepting by imposition of pressure or other means that have been described.

The nature and objects of this invention having been fully described and illustrated, what I wish to claim as new and useful and secure by Letters Patent is:

1. Apparatus for servicing, completing, and producing wells in vertically spaced apart productive horizons penetrated by a Well bore having a casing arranged therein perforated in upper and lower zones and having a tubing with its lower open end permanently arranged above the upper of said zones which comprises a mandrel attached to and forming the lower end of said tubing, said mandrel having an internal diameter greater than the internal diameter of said tubing, a lirst packer arranged on said mandrel adjacent its lower end closing the casing-tubing annulus, a second packer arranged in said casing below the lower end of the mandrel to seal with the wall of the casing between said upper and lower zones, said second packer having an open bore, and a tubular member slidably arranged and maintained in said mandrel, said tubular member being provided with sealing means on its lower end and having a length at least co-extensive with the mandrel and being of suliicient length to extend at least to said second packer, a piston member formed on the upper end of said tubular member and provided with means sealingly engaging with the inner wall of said mandrel, said tubular member being movable from a first posi-X tion in said mandrel to a second extended position by exerting fluid pressure downwardly through said tubing against the piston member whereby the lower end of said tubular member is sealingly arranged in the open bore of said second packer and whereby a ow path through said tubular member and tubing from the lower zone to the earths surface is provided, and means in said mandrel for supporting said tubular member in its first and second positions.

2. Apparatus for servicing, completing, and producing wells in vertically spaced apart productive horizons penetrated by a well bore having a casing arranged therein perforated in upper and lower zones and having a tubing with its lower open end permanently arranged above the upper of said zones which comprises a mandrel attached to and forming the lower end of said tubing, said mandrel having an internal diameter greater than the internal diameterV of said tubing, a first packer arranged on said mandrel adjacent its lower end closing the casing-tubing annulus, a second packer arranged in said casing below the lower end of the mandrel to seal with the wall of the casing between said upper and lower zones, said second packer having an open bore, a tubular member slidably arranged and maintained in said mandrel, said tubular member being provided with sealing means on its lower end and having a length at least co-extensive with the mandrel and being of suiiicient length to extend at least to said second packer, a piston member formed on the upper end of said tubular member and provided with means sealingly engaging with the inner wall of said mandrel, said tubular member being movable from a first position in said mandrel to a second extended position by exerting uid pressure downwardly through said tubing against the piston member whereby the lower end of said tubular member is sealingly arranged in the open bore of said second packer and' whereby a first flow path through said tubular member and tubing from the lower zone to the earths surface is provided, means in said mandrel for supporting said tubular member in its first and second positions, and port means in said mandrel communicating with the casingtubing annulus and forming a second flow path from the upper zone to the earths surface.

3. Apparatus for servicing, completing, and producing vertically spaced apart productive horizons penetrated byv a well bore having a casing arranged therein perforated in upper and lower zones and having a first tubing with its lower open end permanently arranged above the upper of said zones which comprises a mandrel attached to and forming the lower end of said tubing, said mandrel having an internal diameter greater than the internal diameter of said tubing, a rst packer arranged on said mandrel adjacent its lower end closing the casing-tubing annulus, a second packer arranged in said casing below the lower end of the mandrel to seal with the wall of the casing between said upper and lower zones, said second packer' having an open bore, a tubular member slidably arranged and maintained in said mandrel and provided with sealing means on its lower end, said tubular member having a length at least co-extensive with the mandrel and being of sucient length to extend at least to said second packer, a piston member formed on the upper end of said tubular member and provided with means sealingly engaging with the inner wall of said mandrel, said tubular member being movable from a first position in said mandrel to a second extended position by exerting fluid pressure downwardly through said tubing against the piston member whereby the lower end of said tubular member is sealingly arranged in the open bore of said second packer and whereby a first flow path through said tubular member and tubing from the lower zone to the earths surface is provided, means in said mandrel for supporting said tubular member in its first and second positions, and a second tubing with its lower open end permanently arranged in the casing above the upper of said zones, the lower open end of said second tubing extending through said first packer and l forming a second flow path from the upper zone to the earths surface.

4. Apparatus for servicing, completing, and producing wells in vertically spaced apart productive horizons penetrated by a well bore having a casing arranged therein perforated in upper and lower zones and having a tubing with its lower open end permanently arranged above the upper of said zones which comprises a mandrel attached to and forming the lower end of said tubing, said mandrel having an internal diameter greater than the internal diameter of said tubing, a first packer arranged on said mandrel adjacent its lower end closing the casing-tubing annulus, a second packer arranged in said casing below the lower end of the mandrel to seal with the wall of the casing between said upper and lower zones, said second packer having an open bore, a tubular member slidably arranged and maintained in said mandrel and provided with sealing means on its lower end, said tubular member having a length at least co-extensive with the mandrel and being of sufficient length to extend at least to said second packer, a piston member formed on the upper end of said tubular member and provided with means sealingly engaging with the inner wall of said mandrel, said tubular member being movable from a first position in said mandrel to a second extended position by exerting fluid pressure downwardly through said tubing against the piston member whereby the lower end of said tubular member is sealingly arranged in the open bore of said second packer and whereby a first flow path through said tubular member and tubing from the lower zone to the earths surface is provided, means in said mandrel for supporting said tubular member in its first and second positions, and means forming a passageway through said first packer providing a second flow path from the upper zone to the earths surface.

5. Apparatus for servicing` completing, and producing wells in vertically spaced apart productive horizons penetrated by a well bore having a casing arranged therein perforated in upper and lower zones and having a tubing with its lower open end permanently arranged above the upper of said zones which comprises a mandrel attached to and forming the lower end of said tubing, said mandrel having an internal diameter greater than the internal diameter of said tubing, a first packer arranged on said mandrel adjacent its lower end closing the casing-tubing annulus, a second packer arranged in said casing below the lower end of the mandrel to seal with the wall of the casing between said upper and lower zones, said second packer having an open bore, a full opening tubular member having an internal diameter substantially the same as the tubing slidably arranged and maintained in said mandrel and provided with sealing means on its lower end, said tubular member having a length at least co-extensive with the mandrel and being of sufficient length to extend at least to said second packer, a piston member formed on the upper end of said tubular member and provided with means sealingly engaging with the inner wall of said mandrel, said tubular member being movable from a first position in said mandrel to a second extended position by exerting fluid pressure downwardly through said tubing against the piston member whereby the lower end of said tubular member is sealingly arranged in the open bore of said second packer and whereby a first flow path through said tubular member and tubing from the lower zone to the earths surface is provided, means in said mandrel for supporting said tubular member in its first and second positions, and tubular means extending through said first packer and forming a second fiow path from the upper zone to the earths surface.

6. Apparatus for servicing, completing, and producing wells in vertically spaced apart productive horizons penetrated by a well bore having a casing arranged therein perforated in upper and lower zones and having a tubing with its lower open end permanently arranged above the upper of said zones which comprises a mandrel attached to and forming the lower end of said tubing, said mandrel having an internal diameter greater than the internal diameter of said tubing, a first packer arranged on said mandrel adjacent its lower end closing the casing-tubing annulus, a second packer arranged in said casing below the lower end of the mandrel to seal with the wall of the casing between said upper and lower zones, said second packer having an open bore, a tubular member having an internal diameter substantially the same as the tubing slidably arranged and maintained in said mandrel and provided with sealing means on its lower end, said tubular member having a length at least co-extensive with the mandrel and being of sufiicient length to extend at least to said second packer, a piston member formed on the upper end of said tubular member and provided with means sealingly engaging with the inner wall of said mandrel, said tubular member being movable from a first position in said mandrel to a second extended position by exerting uid pressure downwardly through said tubing against the piston member whereby the lower end of said tubular member is sealingly arranged in the open bore of said second packer and whereby a first fiow path through said tubular member and tubing from the lower zone to the earths surface is provided, means in said mandrel for supporting said tubular member in its first and second positions, and tubular means extending through first packer and forming a second ow path from the upper zone to the earths surface.

7. Apparatus for servicing, completing, and producing wells in vertically spaced apart productive horizons penetrated by a well bore having a casing arranged therein perforated in upper and lower zones and having a tubing with its lower open end permanently arranged above the upper of said zones which comprises a mandrel attached to and forming the lower end of said tubing, said mandrel having an internal diameter greater than the internal diam eter of said tubing, a first packer arranged on said mandrel adjacent its lower end closing the casing-tubing annulus, a second packer arranged in said casing below the lower end of the mandrel to seal with the wall of the casing between said upper and lower zones, said second packer having an open bore, a tubular member having an internal diameter substantially the same as the tubing slidably arranged and maintained in said mandrel and provided with sealing means on its lower end, said tubular member having a length at least co-extensive with the mandrel and being of sufiicient length to extend at least to said second packer, a piston member formed on the upper end of said tubular member and provided with means sealingly engaging with the inner wall of said mandrel, said tubular member being movable from a first position in said mandrel to a second extended position by exerting fluid pressure downwardly through said tubing against the piston member, means in said mandrel for latching said tubular member in its first and second positions, the lower end of said tubular conduit being sealingly arranged in the open bore of said second packer in its second position whereby a first ow path through said tubular member and tubing from the lower zone to the earths surface is provided, and tubular means extending through said Ifirst packer and forming a second flow path from the u per zone to the earths surface.

8. Apparatus in accordance with claim 1 in which the tubular member is provided with spring means bearing against the underside of the piston member and against a stop member in the lower end of the mandrel for returning the tubular member from the second to the first position.

References Cited in the file of this patent UNITED STATES PATENTS 2,448,931 Penick NOV. 22, 1949 2,749,989 Huber .lune 12, 1956 2,776,013 Tausch Ian. 1, 1957 2,785,754 True Mar. 19, 1957 2,798,558 McCulloch July 9, 1957

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2448931 *Nov 30, 1944Sep 7, 1948Swanson Carl OSelf-cleaning door mat
US2749989 *Oct 31, 1951Jun 12, 1956Exxon Research Engineering CoMethod and means of completing a well
US2776013 *Mar 11, 1954Jan 1, 1957Exxon Research Engineering CoApparatus for completion in a plurality of hydrocarbon productive strata
US2785754 *Oct 27, 1954Mar 19, 1957Exxon Research Engineering CoPermanent well completion
US2798558 *Jan 10, 1955Jul 9, 1957Exxon Research Engineering CoWell completion apparatus
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3219113 *Nov 9, 1962Nov 23, 1965Shell Oil CoMethod and apparatus for effecting the permanent completion of a well
US4098334 *Feb 24, 1977Jul 4, 1978Baker International Corp.Dual string tubing hanger
US4637468 *Sep 3, 1985Jan 20, 1987Derrick John MMethod and apparatus for multizone oil and gas production
US8418768Dec 9, 2009Apr 16, 2013Ptt Exploration And Production Public Company Ltd.Bypass gaslift system, apparatus, and method for producing a multiple zones well
Classifications
U.S. Classification166/114, 166/189
International ClassificationE21B43/00, E21B43/14
Cooperative ClassificationE21B43/14
European ClassificationE21B43/14