US3444927A - Servicing of wells - Google Patents

Description

May 20, 1969 T, w, CHILDERS ET A1. 3,444,927

SEHVICING OF WELLS Filed Nov. 21, 41967 sheet of 2 SERWCE LINE 3| INVENTORS.

THOMAS W. CHILDERS, Y EDMOND R. GENOIS,

A NEY May 20, 1969 T. w. CHILDERS ET A1. 3,444,927

SERVI C ING OF WELLS (DQ a LU 9 g fmi INVENTORS. -l THOMAS W. CHILDERS,

3 v EDMOND R. GENOIS, U- g BY FTORNEY,

United States Patent O 3,444,927 SERVICING F WELLS Thomas W. Childers, Metairie, and Edmond R. .Genom New Orleans, La., assignors to Esso Production Research Company Filed Nov. 21, 1967, Ser. No. 684,670 Int. Cl. E21b 33/035, 43/01, 7/12 U.S. Cl. 166-.5 10 Claims ABSTRACT 0F THE DISCLOSURE Horizontally spaced apart underwater wells each having at least two pipe strings arranged therein interconnected adjacent their lower ends and each having a dow llne connected to the pipe strings and extending to a remote accessible location are serviced by uidly interconnecting the wells at a point removed from the accessible location and flowing fluid into the first of the wells through its flow line and through the fluid interconnection; the fluid may be used to propel a well tool into one of the wells.

BACKGROUND OF THE INVENTION Field of the invention The present invention is directed to servicing of wells. More particularly, the invention is concerned with the servicing of a plurality of spaced apart underwater wells. In its more specific aspects, the invention relates to method and apparatus for servicing and completing underwater wells wherein common facilities are provided for a plurality of wells.

Description of the prior art It is known to service underwater wells using the so-called through ow line techniques wherein well tools are propelled into and out of a well using uid pressure to run the tools in and out of the well and through curved conduits. When such techniques are employed, however, each well heretofore required at least two ow lines to provide a circulation path to operate the through flow line completion and servicing system. Not only was this expensive because of increased capital investment but also because maintenance and operation costs were increased. It has now been found that only one flow line is needed for each well having a plurality of pipe strings therein by providing in accordance with the present invention, a fluid interconnection with another well and utilizing the interconnection and the ow line of the second well to provide the necessary fluid circulation path. Thus, the present invention reduces the number of fiow lines and auxiliary equipment and provides an unobvious and unexpected result in completion and servicing operations by utilizing common facilities for a plurality of wells. Thus, the flow lines which heretofore were used for only one well may be employed for a plurality of wells.

SUMMARY OF THE INVENTION The present invention may be briefly described and summarized as a method for servicing underwater wells which are horizontally spaced apart. These Wells are provided with at least two pipe or tubing strings which are interconnected adjacent their lower ends. Each well has a ow line connected to the pipe string which extends to an accessible location, usually a production and servicing platform which may be supported in the water either by bottom support means or by lloating means such as a vessel or submerged buoyancy means. Alternatively, the production and servicing means may be located on shore. The wells are fluidly interconnected at a point removed from the accessible location, preferably adjacent water bottom and fluid is flowed into the rst of said wells 3,444,927 Patented May 20, 1969 through its ow line, down one pipe string and up the other and thence through the fluid interconnection and the flow line of the second well to the accessible location. The uid may be used to propel a well tool into and out of either of the wells.

The present invention also involves apparatus comprising means iluidly interconnecting such underwater wells as described herein to each other at a point removed from servicing facilities and control means in the uid interconnecting means for controlling ow of uid through the fluid interconnecting means in combination with the plurality of tubing or pipe strings and the well flow lines.

BRIEF DESCRIPTION OF THE DRAWING The invention will be furthe-r described by reference to the drawing in which:

FIG. 1 is a view partly in section of a pair of spaced apart wells illustrating a preferred mode and embodiment for carrying out the invention.

FIG. 2 is a view illustrating the ow line connection of the wells to a remote production and servicing platform.

FIG. 3 is an enlarged fragmentary view of a portion of the platform of FIG. 2.

FIG. 4 is a schematic view of the servicing facilities on the platform.

DESCRIPTION OF THE PREFERRED MODE AND EMBODIMENTS RELATIVE TO THE DRAWING Referring now to the drawings and particularly to FIGS. 1, 2 and 3, numeral 11 designates a body of water having a Water surface 12 and water bottom 13 which may be the ocean floor. Drilled in the water bottom 13 is a first well 14 and a second well 15 which suitably may be oil and/or gas wells. Well 14 has a casing 16 cemented in place by cement sheath 17. Well 14 is provided with a first tubing or pipe string 18 and a second tubing or pipe string 19 which are interconnected adjacent their lower ends by fluid interconnection means 20.

Well 15 has a casing 21 arranged therein and cemented with cement sheath 22. Well 15 is provided with a tubing or pipe string 23 and a second tubing or pipe string 24 which are interconnected by fluid interconnection means 25.

The lower end of pipe string 18 has an opening 26 and the lower end of pipe string 24V has an opening 27.

The wells 14 and 15 and the casings 16 and 21 have been perforated in a producing formation 28 from which oil and/or gas may be produced by perforations 29 in well 14 and performations 30 in Well 15.

The tubing strings 18 and 19 and 23 and 24 are fluidly interconnected by a service line 31 provided with valve control means 32 and 33. A flow line 34 connects to the service line 31 and to the tubing strings 18 and 19 and a second ow line 35 connects to the service line 31 and to the tubing or pipe strings 23 and 24. The tubing strings 18 and 19 are controlled by means of valve control means 36 and 37 while the tubing or pipe strings 23 and 24 are controlled by valve control means 38 and 39.

The flow lines 34 and 35 extend to a platform 40 (FIG. 2) on which are located production and servicing facilities -generally indicated `by the numeral 41. As shown in FIG. 4, the production and servicing facilities may include storage means such as tankage 42. Lines 43 and 44 connect respectively to lines 34 and 35; by providing pump means 70, which is connected by branch lines 45 to lines 43 and 44 and well tool insertion means 46 and by suitable manipulation of valves 47, 48 49, 50, 51 and 52, it is possible to pump into and out of the wells 14 and 15 and propel well tools into and out of the wells 14 and 15. Pump means 70 is also connected to tankage 42 by maniold 71 provided with valves 72.

In accordance with the present invention, it may be desirable to run a well tool such as a tubing extension member 53 into the Well 14 through tlow line 34 as shown in FIG. 1. Under these circumstances, in accordance with the present invention, the tubular extension mem- =ber provided with a sealing means 54 which acts as a piston, may be inserted in the well insertion means 46 (FIG. 4) and introduced through line 43 into a flow line 34 by means of uid pumped thereinto. The tubular extension member travels through the production ow line 34 (FIG. 2) around the radius bend 55 and down the tubing string 18 to be seated in a landing nipple 56 above the fluid interconnection 20 such that the tubing extension 53 extends below the opening 26 which will allow the introduction of a suitable well servicing uid into it adjacent perforations 29. The fluid interconnection 20 and the service line 31 .and the ow line 35 provide a circulation path for the fluid which is flowed down the pipe or tubing string 18. Of course, it is understood that the valves 36, 37 and 33 are open and valves 38 and 39 and 32 are closed during this operation. When it is desired to remove well tools such as tubing extension 53, the ow is reversed. To this end the valves 38 and 39 and 32 remain closed and valves 33, 36 and 37 remain open. Fluid is flowed down the iiow line and through the service line 31 and down the tubing or pipe string 19 against the piston 54 which causes it to be released from the landing nipple 56 and to travel up- Wardly through the tubing or pipe string 18 and thence to the production and servicing facilities 41 through How line 34.

The production or servicing facilities 41 may suitably be located on a platform supported by structure 61 on water bottom 13 as shown in FIGS. 2 and 3. The platform 40 may also be on shore or it maybe supported by a floating vessel or by submerged buoyancy means such as the seadrome type. With respect to the particular embodiment of FIG. 2, however, the ow lines 34 and 35 are brought to the platform 40 by liow line risers 62 which may suitably be installed on a rail 63 (FIG. 3) such as described in U.S. Patent 3,226,728 issued in the name of J ames G. Walvoord.

The valves 32, 33, 36, 37, 38, and 39 are, of course, inaccessible from the surface; therefore, it is necessary to operate these valves remotely from an accessible location such as the platform 40. To this end, lines 65, 66, and 67 may be connected to valves 32, 36, and 37, respectively, and similar lines may be connected to valves 33, 38, and 39. These lines may be electrical connecting means or pneumatic or hydraulic lines to operate the service valves. These lines 65, 66, and 67 may extend to the platform 40 for operation of the valves as may be desired. The remote operation of such valves is Well known and a description of such remotely operated valves may be found in Composite Catalog 1964-65, volume I, page 1230 (Cameron Iron Works, Inc. Fail Safe Valves).

While a plurality -of control lines 65, 66 and 67 have been described, it is to be -understood that one line controlled from the platforms may be used to operate valves 32, 33, 36, 37, 38 and 39 by pilot or selector switches at the Christmas tree to operate the proper valve or upon receiving a signal. The control lines may be eliminated by using acoustically controlled valves which require no physical connection with the platform.

It will be manifest that the present invention is quite advantageous and useful in that it eliminates the number of lines and, therefore, investment, maintenance, and operating costs over that heretofore required.

As an example of the present invention, in a 40 acre spacing of wells, paired well such as 14 and 15 may be about 1300 feet apart; therefore, the service line 31 may be about 1300 feet long. The flow line requirements for two wells such as 14 and 15 from a production platform such as 40 may be about 4.25 miles with underwater flow line connections totaling six in number. The present invention, by reducing the mileage of flow lines underwater connections and the number of risers, allows the obtaining of marked and unobvious advantages.

The well servicing fluids employed in the present invention may include by Way of illustration and not by way of limitation, cement slurries drilling muds, oil and water emulsions, perforating fluids such as gels and the like, and stimulating liquids such as hydraulic fracturing liquids, acids, solutions of surfactants in oil and/or water, aqueous or oily solutions of corrosion inhibitors and the like, liquid sand consolidation uids such as resins, etc., and slurries of clay, bentonite, and other similar materials.

The well tools which may be run into and out of the Wells, in accordance with the present invention, include by way of illustration and not by way of limitation, tubular extension members, logging tools and sondes, bottom hole pumps, rbottom hole pressure measuring devices, and the like.

The nature and objects of the present invention having been completely described and illustrated and the best mode and embodiment contemplated set forth what we wish to claim as new and useful and secure by Letters Patent is:

1. A method for servicing at least first and second horizontally spaced apart underwater wells each having at least two pipe strings arranged therein interconnected adjacent their lower ends and each well having .a oW line connected to said pipe strings and extending to an accessible location, which comprises:

fluidly connecting said wells to each other at a point removed from said accessible location; and

owing uid into the tirst of said Wells from said' accessible location through its ow line down one pipe string and up the other and thence through said lluid interconnection and the ow line of said second well to said accessible location.

2. A method in accordance with claim 1 in which a well tool is inserted into the ow line of said first well at said accessible location and run into said well with said fluid.

3. A method in accordance with claim 2 in which the well tool is removed from said well by owing uid through the tiow line of the second well, through said fiuid interconnection, down the other pipe string and up the one pipe string of the first well, and thence through the flow line of the first well to the accessible location.

4. A method in accordance with claim 1 in which the wells are iiuidly interconnected at a point adjacent water bottom.

5. A method in accordance with claim 1 in which the fluid flowed into the first of said wells is a servicing iiuid.

6. A method in accordance with caim 1 in which the fluid is cement.

7. A method in accordance with claim 1 in which the accessible location is a production platform horizontally spaced from said wells.

8. In a well servicing system comprising at least first and second horizontally spaced apart underwater wells each having at least two pipe strings arranged therein interconnected adjacent their lower ends and each having a flow line connecting to said pipe strings and to servicing means horizontally spaced from said Wells, apparatus which comprises:

conduit means fluidly interconnecting said Wells to each other at a point removed from said servicing means; and

control means in said uid interconnecting means for controlling the flow of fluid through said uid interconnecting means.

9. Apparatus in accordance with claim 8 in which the control means comprises valve means operated from said servicing means for controlling ow of uid into 3,136,363 6/ 1964 Yetman et ai 166-95 X and out of said Wells. 3,139,928 7/1964 Broussard 166-2 10. Apparatus in accordance with claim 8 in which 3,331,753 5/1968 Fredd 166 154X the fluid interconnecting means is a conduit connected to said wells at a point adjacent water bottom. 5 CHARLES E. OCONNELL, Primary Examiner.

References Cited J. A. CALVERT, Assistant Examiner. UNITED STATES PATENTS U-'S- CL X-R- 3,003,560 10/1961 `Corley et al. 166-.5 X 166-46, 52

3,111,692 11/1963 Cox 166-.5 X 10

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