US2796130A

US2796130A - Method and apparatus for working over wells

Info

Publication number: US2796130A
Application number: US470343A
Authority: US
Inventors: Theodore A Huber
Original assignee: Exxon Research and Engineering Co
Current assignee: ExxonMobil Technology and Engineering Co
Priority date: 1954-11-22
Filing date: 1954-11-22
Publication date: 1957-06-18
Anticipated expiration: 1974-06-18

Description

June 18A, 1957 T'. A. HUBER METHOD AND APPARATUS FOR WORKING OVER WELLS Filed Nov. 22, 1954 Z Ww,

METHD AND APPARATUS FOR WORKING GVER WELLS Theodore A. Huber, Houston, Tex., assigner, by mesne assignments, to Esso Research and Engineering Company, Eiizabeth, N. J., a corporation of Delaware Application November' 22, 1954, Serial No. 470,343

15 Claims. (Cl. 166-21) The present invention is directed to a method and apparatus for conducting operations in a cased and tubed well. More particularly, the invention is directed to method and apparatus for use in a cased 'and tubed well in which the tubing is arranged having its lower end fixed at a point substantially above a point where fluids are to be introduced into the well. In its more specific aspects, the invention has to do with introducing fluid materials, such as cement, into a well at a point below the open end of the tubing string.

This application is a continuation-impart of Serial No. 386,717, entitled Method and Apparatus for Workover Operations in Wells, filed October 19, 1953, in the name of Theodore A. Huber, now abandoned.

The present invention may be briefly described as apparatus for conducting workover operations and the like in a cased and tubed well in which the lower end of the tubing is arranged at a substantial distance above a point where certain workover operations are to be conducted without manipulating the tubing. The apparatus comprises a tubular member open at both ends adapted to be secured to the tubing and form a continuous passageway with the tubing. The tubular member is -comprised of a first section adapted to be secured at a first end in said tubing and a second section having a rst end slidably arranged or telescoped in the secon-d end of the first section. The second section is provided with valve means for closing the passageway; the valve means may be arranged on the first end of the second section but also may be suitably arranged on the second end thereof. Biasing means are provided in the first section which normally urge the second section to a first position in the first section. The second section is adapted to assume a second position when the passageway is closed or restricted by the valve` means and pressure is exerted against the valve means to hold it in a closed position.

'Ihe valve means employed in the practice of the present invention may comprise a spherical member, such as a ball, which may be dropped down the passageway to seat on Ia seat provided on the upper end of the second section. When it is desired to open the valve member comprising a spherical member, the ball may be unseated by pressure exerted from below.

'Ihe present invention is also concerned with a method for spotting cement in a well and squeeze cementing and also for introducing fluid material in the well. For example, in a perforated casing it may be desirable to introduce'fluid cement into the well adjacent the perforations when the tubing is locatedat a point a substantial distance above the point where the cement is to be spotted and squeezed. Thus a path `of flow may be established from the open end of the tubing isolated from the casing to the point where cement or other iiuid material is to be spotted. Thereafter pressure may be exerted on the cement either through the annulus between the tubing and the casing or through the tubing. After the cement has been squeezed through the perforations and it is desirable to remove excess cement the path of flow is extended to a States Patent O ICC point below the squeeze operation so that all of the cement may be removed by circulating liuid, such as salt water, down the annulus cand up the' extended path of iiow and the tubing.

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

Fig. 1 is a crosssection of the apparatus in a first position suspended from the open end of a tubing;

Fig. 2 is a cross-sectional view of the apparatus of Fig. l ina second position;

Fig. 3 shows the apparatus of the present invention employed in cementing operations; and

Fig. 4 is a modification of the valvemeans of the apparatus Iof Figs. l to 3.

Referring now to the drawing and specifically to Figs. l to 3, numeral 11 designates a well which has been drilled from the earths surface, not shown, to penetrate a plurality of subsurface formations. Arranged in the well 11 is a casing 12 which has been cemented in place with cement 13. Suspended from the earths surface, not shown, from the wellhead, `also not shown, in the casing 12 is a tubing string 14. This tubing string is provided with a supporting means 15 adjacent its open lower end. This supporting means may suitably be a landing nipple, pipe slips, latching dogs and other engaging means well known to the art where one piece of well equipment may be suspended in another. Supported on the supporting means 15 by means of a shoulder 16 is a tubualr extension member 17 which is comprised of a first section 18 and a second section 19. The tubular member 17 may suitably be sealed within the tubing 14 by means of a sealing means 20 which may be a packer or other sealing means known tothe art. The tubular member 17 is provided on its upper end with engaging means 21 which is connected by means of an engaging grab `and wire line not shown for lowering and raising the tubular member 17 in the tubing 14. The tubular member 17 is open at its upper end for passage of fluid down the tubing and through the tubular member 17.

The lower end of the first section 18 has a closure member or shoulder 25 which defines a passageway 26. Arranged in the lower end of the first section 18 and projecting through the passagewayy 26 is the second section 19 having a first end 27 of reduced diameter. The first end 27 of the second section 19 has a shoulder 28 on its upper end which defines a recess 29 and a seating member 30. Arranged in the recess 29 is -a snap ring 31 which engages frictionally with `the wall of the first section 18. The wall of the first section 18 has a groove 32 adjacent the lower end thereof adapted to receive the ring 31. Seating on seat 30 is a ball or spherical member 33 which is yadapted to be dropped down through the tubing 14 and to be passed through the .open upper end of the tubular member 17. Surrounding the lower end 27 of the second section 19 is a biasing means, such as a coil spring 34, which bears frictionally against the shoulder 28 and also against the shoulder 25 and normally urges the second section 19 to a rst position as shown in Fig. l. Y Y

Referring now specifically to Fig. 3, it will be seen that the second section 19 is arranged in its first position with its lower end 35 adjacent or in the vicinity of perforations 36 in the casing112. These perforations 36 may suitably have been formed prior to lowering the extension member 17 through the tubing 14. That is, prior to lowering the tubing extension 1 '7 a tubing gun perforator of the wellknown type may be lowered through the tubing -14 opposite the formation or strata 37 and the perforator operated to cause the perforations 36. It is understood, of course, that a first set or original perforations 36 may have been formed prior to the time tubing 14 is run into the casing 12. A

After the extension member 17 has been lowered with the end 35 of the section 19 in the area of the perforations 36, saltwater or other clean fluid 38 may be pumped out the open end 35 and followed by a body of Huid cement such as a low water loss cement 39. Such low water loss cement may be a cement such as described by Salathiel in U. S. Patent 2,482,459. Other uid cements or low water loss cements may be employed, such as oil-emulsion cements and chemically prepared low water loss cements available on the market. However, I do not restrict myself to using low water loss cements since l may use other fluid cements.

The invention may also be used in depositing treating reagents, and the like, in wells and thereafter removing same. For example, gelled acid, uid plastics, gelled hydrocarbons, emulsions, and the like may be introduced into a well and then removed completely or in part by the apparatus and method of the present invention.

The low water loss cement 39 is then followed by mud, oil, salt water or other fluids and the cement may then be squeezed through the perforations 36 by means of pressure either exerted on the annulus A or through the tubing 14 and tubular member 17. It may be preferred to exert the pressure through the tubing and tubing extension 17 with the annulus A in a closed-in condition.

After the cement has been squeezed, a spherical member, such as ball 33, may be introduced into the tubing by means well known to the art, such as lubricating, and dropped down through the tubing 14, tubular member 17 to seat on the seat to close off the passageway 49 which is comprised of the tubing 14 and the extension member 17 Pressure is then exerted on the passageway 49 which causes the second section 19 to assume a second position as shown in Fig. 2 and as indicated in Fig. 3 by the dotted lines. Thereafter the annulus A may be opened and the tubing 14 opened at the surface and uid pumped down the annulus A to allow washing out of the body of cement 39 from the casing. This permits removing cement that would otherwise remain opposite the perforations and between positions 1 and 2 of the lower end 35 of section 19. It would be impractical to remove member 17 and replace it with a longer tubular extension because the cement would have taken initial set during such trip out of and back into the well. Thereafter the tubing extension 17 composed of

sections

18 and 19 may be pulled from the tubing 14 by means of wire line (not shown) and subsequent operations conducted in the well.

It is to be understood that the operations may be conducted in many ways. For example, it may be desirable and preferred to remove the cement 39 by circulation out with the member 19 in a first position as shown in Fig. 3 until the level of cement has dropped to the level of the lower end 3S of the member 19. The spherical member 33 may then be dropped into the tubing 14 and seated, as

shown in Figs. l and 2. Pressure is then exerted down the I tubing 14 to force the member 19 to the position shown by the dotted lines in Fig. 3. Thereafter, the scavenging fluid such as water, oil, or mud is then circulated down the casing and additional cement is removed down to the point to which the end member 35 extends.

It is also contemplated that my apparatus may be provided with a series or plurality of recesses 32 such that the member 19 may be lowered or extended stepwise as may be desired.

It is further intended that other means, such as dogs, gripping means, and the like may be provided on shoulder 28 to engage with the inner wall of member 18 to hold member 19 at any point therein as may be desired.

Referring now to Fig. 4, the section 19 is modified to provide a valve seal on an annular shoulder 56 arranged in the lower end 3S of the section 19'. Where the valve seat 55 is provided for a sphere 33', the section 19 may be constructed to provide an uninterrupted passageway for the sphere 33. Stating this otherwise, the section 19' does not increase and/or decrease in diameter throughout its length.

Cil

The apparatus of Fig. 4 operates similarly to Fig. l.

It is to be understood that the apparatus of the present invention may be utilized in spotting and removing other materials besides uid cement in a cased well. For example, it may be used to introduce acids, gels and the like materials into a Well or into a strata or formation and thereafter allow removal of same.

The present invention is quite advantageous in that the cementing operation may be conducted without manipulating the tubing 14 and furthermore eliminates the necessity of going back into a well to drill out cement, such as required in the prior art. As pointed out before, it is also unnecessary to come out of the casing 12 and tubing 14 with member 17 to provide a longer member 17 for the purpose of removing all of the fluid cement from the casing 12 as is possible with my invention. The present invention is advantageous in that the well is kept in a live condition. In short, it is unnecessary to kill the well with mud. Furthermore, heavy duty pulling equipment is not required.

The apparatus may be modified without departing from the spirit and scope of the claims. For example, the section 19 may be modified as described by increasing or decreasing its diameter or by providing a section 19 of uniform diameter throughout its length.

ln the description of the invention, it is to be understood that the section 19 is lowered a suflicient distance to reverse out the uid cement remaining after the squeeze job. This distance may vary depending on a number of variables among which are the velocity at which cement is pumped in or deposited in the well, differential gravity of cement and well fluid, and relative viscosities of cement and well uids. ln some instances the distance the section 19 is lowered may be only a few feet whereas in other instances the distance may be larger. To reverse out the remaining fluid cement the section 19 is lowered below the lowermost point where the cement is spotted or located.

The nature and objects of the present invention having been completely described and illustrated, what l wish to claim as new and useful and to secure by Letters Patent is:

l. A method for depositing in and removing a treating reagent and the like from a cased and tubed well in which the lower end of the tubing is arranged a substantial distance above a first level in the casing where the treating reagent is to be deposited and then removed which comprises forming a path of flow isolated from the casing from the lower end of the tubing to the first level where said treating reagent is to be deposited, flowing said treating reagent down said tubing and along said path of ow to deposit a body of said treating reagent in said casing, forcing said treating reagent into perforations in said casing, closing said path of flow` applying fluid pressure downwardly through said tubing to extend said closed path of flow to a level at least below thc upper level ol said body while maintaining said tubing stationary, opening said closed path of flew, and then removing at least a portion of said body through said extended path of flow and said tubing.

2. A method in accordance with claim l in which the treating reagent is fluid cement.

3. A method in accordance with claim l in which the treating reagent is gelled acid.

4. A method in accordance with claim l in which the treating reagent is an emulsion.

5. A method in accordance with claim 1 in which the treating reagent comprises gelled hydrocarbons.

6. A method in accordance with claim l in which the treating reagent comprises a plastic.

7. A method for depositing in and removing a treating reagent and the like from a cased and tubed well in which the lower end of the tubing is arranged a substantial distance above a first level in the casing where the treating reagent is to be deposited in and removed, which comprises forming a path of ow isolated from the casing from the lower end of the tubing to the first level where said treating reagent is to be deposited, fiowing said treating reagent down said tubing and along said path of 'ow to deposit a body of said treating reagent in said casing, forcing said treating reagent into perforations in said casing, restricting downward fiow of fiuid through said path of fiow, applying downward fiuid pressure to said path of fiow to effect lengthening of said path of flow to a second level at least below the upper level of said body while maintaining said tubing stationary, and then removing at least a portion of said body through said extended path of fiow and said tubing.

8. Apparatus for conducting workover operations in a cased and tubed well in which the lower end of the tubing is arranged above a point where said operations are to be conducted without manipulating the tubing which comprises a tubular member open at both ends adapted to form a continuous passageway with said tubing, said tubular member being comprised of a first section retrievably and sealingly secured at its first end in said tubing and a second section having its first end slidably arranged in the second end of the first section, valve means for closing said passageway arranged in said second section, and biasing means embracing the first end of the second section and urging said second section to a first position in said first section, said second section being adapted to assume a second position to extend substantially the length of the tubular member when said passageway is restricted by said valve means and pressure is exerted against said valve means to hold it in closed position.

9. Apparatus in accordance with claim 8 in which the valve means comprises a spherical valve member.

10. Apparatus for conducting workover operations in a cased and tubed well in which the lower end of the tubing is arranged above a point where said operations are to be conducted without manipulating the tubing which comprises a tubular member open at both ends adapted to form a continuous passageway with said tubing, said tubular member being comprised of a first section retrievably and sealingly secured at its first end in said tubing and a second section having its first end of decreased diameter slidably arranged in the second end of the first section, means on the first end of said tubular member for lowering and raising said tubular member in said tubing, valve means for closing said passageway arranged in said second section, and biasing means embracing the first end of the second section and urging said second section to a first position in said first section, and said second section being adapted to assume a second position to extend substantially the length of the tubular member when said passageway is restricted by said valve means and pressure is exerted against said valve means to hold it in closed position.

l1. Apparatus for conducting workover operations in a cased and tubed Well in which the lower end of the tubing is arranged above a point where said operations are to be conducted without manipulating the tubing which comprises a tubular member open at both ends adapted to form a continuous passageway with said tubing, said tubular member being comprised of a first section retrievably and sealingly secured at its first end in said tubing and a second section having its first end of decreased diameter slidably arranged in the second end of the first section, said second section defining an external shoulder with its first end, means on the first end of said tubular member for lowering and raising said tubular member in said tubing, valve means for closing said passageway arranged in said second section, and biasing means bearing frictionally against said shoulder embracing the first end of the second section and urging said second section to a first position in said first section, said second section being adapted to assume a second position to extend Vsubstantially the length of the tubular CII member when said passageway is restricted by said valve means and pressure is exerted against said valve means to hold it in closed position.

12. Apparatus for conducting workover operations in a cased and tubed well in which the lower end of the tubing is arranged above a point where said operations are to be conducted without manipulating the tubing' which comprises a tubular member open at both ends adapted to form a continuous passageway with said tubing, said tubular member being comprised of a first section retrievably and sealingly secured at its first end in said tubing and a second section having its first end of decreased diameter slidably arranged in the second end of the first section, said second section defining an external shoulder provided with a seating member, means on the first end of said tubular member for lowering and raising said tubular member in said tubing, spherical valve means for closing said passageway, said spherical valve means being adapted to be dropped through said passageway and close same on seating on said seating means, and biasing means embracing the first end of the second section and urging said second section to a first position in said first section, said second section being adapted to assume a second position to extend substantially the length of the tubular member when said passageway is restricted by said valve means and pressure is exerted against said valve means to hold it in closed position.

f3. Apparatus for conducting workover operations in a cased and tubed well in which the lower end of the tubing is arranged above a point where said operations are to be conducted without manipulating the tubing which comprises a tubular member open at both ends adapted to form a continuous passageway with said tubing, means for sealing between said tubular member and said tubing, said tubular member being comprised of a rst section retrievably secured at its first end in said tubing and a second section having its first end of decreased diameter slidably arranged in the second end of the first section, said second section defining with its first end an external shoulder provided with a seating member, means on the first end of said tubular member for lowering and raising said tubular member in said tubing, spherical valve means for closing said passageway, said spherical valve means being adapted to be dropped through said passageway and close same on seating on said seating means, and a spring embracing the first end of the second section and urging said second section to a first position in said first section, said second section being adapted to assume a second position to extend substantially the length of the tubular member when said passageway is restricted by said valve means and pressure is exerted against said valve means to hold it in closed position.

14. Apparatus for conducting workover operations in a cased and tubed-well in which the lower end of the tubing is arranged above a point where said operations are to be conducted without manipulating the tubing which comprises a tubular member open at both ends adapted to form a continuous passageway with said tubing, means for sealing between said tubular member and said tubing, said tubular member being comprised of a first section retrievably secured at its first end in said tubing and a second section slidably arranged in the second end of the first section, said second section defining with its second end an internal shoulder provided with a seating member, means on the first end of said tubular member for lowering and raising said tubular member in said tubing, spherical valve means for closing said passageway, said spherical valve means being adapted to be dropped through said passageway and close same on seating on said seating means, and a spring embracing the first end of the second section and urging said second section to a first position in said first section, said second section being adapted to assume a second position to extend substantially the length of the tubular member 7 when said passageway is restricted by said valve means and pressure is exerted against said valve means to hold it in closed position.

15. Apparatus in accordance with claim 8 in which the tubular member is provided with a locking means 5 for holding the second section in the second posiion.

References Cited in the le of this patent UNITED STATES PATENTS Granger Ian. 12, 1943 Abendroth Nov. 9, 1954

Claims

1. A METHOD FOR DEPOSITING IN AND REMOVING A TREATING REAGENT AND THE LIKE FROM A CASED AND TUBED WELL IN WHICH THE LOWER END OF THE TUBING IS ARRANGED A SUBSTANTIAL DISTANCE ABOVE A FIRST LEVEL IN THE CASING WHERE THE TREATING REAGENT IS TO BE DEPOSITED AND THEN REMOVED WHICH COMPRISES FORMING A PATH OF FLOW ISOLATED FROM THE CASING FROM THE LOWER END OF THE TUBNG TO THE FIRST LEVEL WHERE SAID TREATING REAGENT IS TO BE DEPOSITED, FLOWING SAID TREATING REAGENT DOWN SAID TUBING AND ALONG SAID PATH OF FLOW TO DEPOSIT A BODY OF SAID TREATING REAGENT IN SAID CASING.