US2795281A

US2795281A - Apparatus for use in squeeze cementing and the like

Info

Publication number: US2795281A
Application number: US361234A
Authority: US
Inventors: Lawrence D Christian
Original assignee: Exxon Research and Engineering Co
Current assignee: ExxonMobil Technology and Engineering Co
Priority date: 1953-06-12
Filing date: 1953-06-12
Publication date: 1957-06-11
Anticipated expiration: 1974-06-11

Description

| D. CHRISTIAN 2,795,281

APPARATUS FOR USE IN SQUEEZE CEMENTING AND THE LIKE 2 sheets-sneet 1 June 11,1957

Filed June 12, 19.5 3

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` June 1,1, 1957 Ln D. CHRISTIAN 2,795,281

APPARATUS FOR USE 1N sQUEEzE CEMENTING AND THE LIKE Filed June 12, 195s 2 Sheets-Sheet 2 INVENTozg. Lawrence D. Chrisllan,

l ATTORNEY.

APPARATUS FR USE IN SQUEEZE CEMENTING AND THE LIKE Lawrence D. Christian, Monroe City, Tex., assigner, by mesne assignments, to Esso Research and Engineering Company, Elizabeth, N. J., a corporation of Delaware Application .lune 12, 1953, Serial No. 361,234

6 Claims. (Cl. 166--120) The present invention is directed to apparatus for squeeze cementing. More particularly, the invention is directed t-o an apparatus for use in squeeze cementing in a well bore. In its more specific aspects, the invention is directed to a squeeze cementing apparatus for squeezing cement without imposing on a well casing a pressure sufficient to damage the well casing.

lThe present invention may be described briey as an apparatus for use in a well casing which is adapted to be connected into a pipe string. The apparatus comprises an outer mandrel provided with spaced apart first and second ports. Arranged within and attached to the outer mandrel is an inner sleeve which is spaced apart from the outer mandrel to define with the outer mandrel an annular passageway from the spaced apart first and second ports. Slidably mounted on the outer mandrel between the spaced apart ports is a packing assembly normally held against slidable movement thereof. The packing assembly is provided with at least one sealing means and may be provided with clamping means for engaging the packing assembly with the wall of the casing. Attached to the outer mandrel adjacent the second of the spaced apart ports is a conduit. Attached to the conduit is a liner setting means for a blank liner which is releasably attached to the liner setting means. The blank liner has attached to a free end thereof a set shoe and a back pressure valve, both of which may be arranged within a common assembly. Arranged within the liner setting means and attached to the conduit is a Wash pipe which has a packing means arranged adjacent a free end of the wash pipe for sealing between the wash pipe and the blank liner against upward tlow in the well bore past the wash pipe.

The present invention is used in well cementing operations and particularly in well cementing operations in which a blank liner is set in an open hole below a casing seat. The invention is particularly useful in squeeze cementing operations in which pressures are employed which might damage the well casing. Thus in the present invention the pressure employed in the squeeze cementing operation is impressed on the cement to be squeezed through the tubing or pipe string on which the apparatus is arranged.

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

Fig. l is a view in partial section of an upper portion of the apparatus of the present invention attached to a pipe string and arranged in a well;

Fig. 2 is a view in partial section of a lower portion of the apparatus of the present invention apart from Fig. 1;

Fig. 3 is a fragmentary sectional view of Fig.1;

Fig. 4 is a partial sectional view of the releasing assembly of Fig. 2;

Fig. 5 is an illustration of the use of the apparatus n of the present invention in placing cement in a hole;

Fig. 6 is an illustration of the apparatus during a squeeze cementing operation; and

fait States Patent O 2,795,281 Patented June 11, 1957 Fig. 7 illustrates reverse circulation where excess cement is removed from the liner.

Referring nowto the drawing, numeral 11 designates an outer mandrel provided on one end thereof with a pipe connecting means 12 provided with mating threads 13 for connecting to a pipe string'14 which extends to the well head, not shown. The outer mandrel 11 is `provided with first and second spaced apart ports designated respectively by

numerals

15 and 16. Arranged within the outer mandrel and spaced apart therefrom and attached to the outer mandrel is an open sleeve 17 which is attached to the outer mandrel by a pin 17 and in sealing relationship with/said outer mandrel at a first end 1S and a second end 19. It will be noted that the outer mandrel 11 and the sleeve 17 define an annular passageway 20 between the

ports

15 and 16.

Slidably mounted on the mandrel l1 and normally held against movement thereon, as will be described in more detail hereinafter, is a packing assembly generally indicated by numeral 21. The packing assembly comprises a rubber collar or sleeve 22 which may be suitably constructed of other deformable materials, if desired, which is retained by an annular member 23 connected to the sleeve 22 by threaded screws 24.

The packing assembly 21 is held on the outer mandrel 11 normally against movement by a releasable locking mechanism generally indicated by the numeral 25 which will be described in more detail hereinafter. Arranged on the sleeve 22 is a clamping ring 26 which is engaged with the sleeve 22 by means of threaded screws 27 and serves to hold same in place, as shown. The member 26 is threadably connected to a wedge member 27 which is arranged to move downwardly within a slip mechanism designated generally by the numeral 28. The slip mechanism 28 has a slip cage 28a and is provided with a plurality of drag springs 29 and slips 30 arranged circumferentially in the slip cage 28a for movement outwardly through windows 31 into engagement with the wall of the Well casing.

The releasable locking mechanism 2S includes threads 32 which are formed on mandrel 11 and on internally threaded member 33 provided with an annular spring 33a both contained within slip cage 28a. Arranged below the slip assembly 28 is a packing or sealing means 34 which may be a swab cup and the like. The sealing means or packing assembly 34 is connected to cage 28a by threaded screws 35.

Connected to the lower end of the mandrel 11 is a pipe connecting means 36 which is connected to a pipe conduit 37 and the like by mating threads 33 and actually is an extension of the mandrel 11. The conduit 37, depending on the particular situation, may have a length anywhere from about 30 to about 300 feet. The pipe conduit 37 is threadably connected by means of mating threads 39 into a sleeve or collar 40. Sleeve or collar 40 is connected to a setting sleeve mandrel on inner sleeve 41 by mating threads 42. Setting sleeve mandrel 41 is provided with a spline or key 43 on which a threaded nut 44 is Slidably splined or keyed. Threaded nut 44 threadedly engages with rough internal threads 45 of a sleeve 46 which is threadedly attached by threads 46a to blank liner 47 `and forms a part thereof. The Slidably splined or keyed nut 44 and threads 45 comprise a releasable connecting means for releasably connecting the blank liner 47 to the conduit 37. Connected to the lower end of the setting means mandrel 41 by mating threads 49 is a wash pipe 50 which extends into the liner 47 as shown. On the lower end of the wash pipe 50 is at least one swab cup or packing means 51 which is shown in the drawing as two in number although only one packing means may be used; if desired, a plurality of packing means may be used.

The wash pipe 50 has a lower open end 52 for circulation through the wash pipe as will be described. Connected to the lower end of the blank liner 47 by means of mating threads 53 is a combination set shoe and back pressure valve apparatus 54. The set shoe 54 has at least a port 5S for placing cement around the blank liner 47 and is provided with bit blades 54a, ask will be described. In the set shoe mechanim 54 is at least one back pressure valve 56 provided with a seating member 57 and normally biased into a closed position by means of a biasing means, such asa helical coil `spring 58. As shown in the drawing, the valve is designed for :maintaining a positive seal, and two are shown, but only one valve mechanism may be used.

It will be noted that a continuous passageway 60 extends from the pipe 14 through the mandrel 11, the packing assembly 21 and down through the conduit 37, the setting tool 40, the open end 52 of wash pipe 50, and the blank liner 47 Also it will be noted that means of communication through the ports and 16 is provided through the passageway 20.

In operating the present invention, the improved apparatus of the present invention may be made up, as described, and run into the hole, the blank liner 47 and the set shoe and back pressure mechanism S4 being set on bottom in an open hole section below a casing. Circulation would then be established down the pipe 14 from the well head, not shown, through the passageway 60 and including the open end 52 and outwardly through the valve 57 and the ports 55 around the liner 47 and thence up the annulus A and back into the apparatus through the ports 16, thence through the passageway 2.0 and outwardly through port 15 and up the annulus A. The circulation, as has` been described, may be achieved after the blank liner has been disengaged, as will be described, although it may be desirable under some circumstances to establish circulation prior to disengagernent.v Thereafter, by rotating the apparatus to the right by the usual rotating means at the well head, not shown, the left-hand threads 45 are disengaged from the nut 44 and the blank liner is left in the bottom of the hole as shown in Fig. 5, the blank liner 47 being held against rotation by means of bit blades 54a. The assembly is picked up by the hoisting equipment a sufficient distance to allow the packer to be set as will be described hereinafter.

Cement is then pumped down from the well head through pipe 14 through the passageway 60 and through the opening 52 and thence out through the ports 55 around the outside of the blank, liner 47, a suicient amount of cement being pumped around the liner 47 to ll the space S in the open hole between the blank liner 47. The packer is then set by again rotating to the right which causes the releasing assembly 25 to discngage the packing assembly and allow slidable movement on the mandrel 11. Thus it is possible to move the mandrel 11 downwardly with respect to the packing assembly 21. On downward movement of the pipe connecting means 12 it cornes to rest against the member 23 which allows weight to be set dov/n on the sleeve 22 `on the wedge means 27 which on movement downwardly causes the slips 30 to move into and engage and set with respect to the wall of the casing, the drag springs 29 engaging thc wall of the casing for setting of the packer assembly 21. Pressure is then exerted downwardly through the means of communication including passageways 60 and opening 52 and ports 55 against the swab cup or packing means 34 causing it to seal with the wall of the casing. This operation is shown in Fig. 6. This allows pressure to be exerted on the cement and cause the squeeze job to be performed successfully.

After the squeeze job has been performed, the pipe 14 is picked up causing the mandrel 11 to be moved upwardly and also causing the releasing means 2,5 to engage again with the threads 32.

It is then possible to circulate out excess cement which remains in the blank liner 47 below the wash pipe 50 by pumping into the annulus A. In this particular operation, drilling mud and the like, which may include salt or fresh water, is pumped down the annulus A through the ports 15 into the passageway 20 and out through the ports 16 and again into the annulus A and thence into an annulus A between the wash pipe and the blank liner 47 as shown in Fig. 2, the swab cup 51 being of a nature to resist flow in an upward direction but not to resist flow in a downward direction. l`his allows the cement to be reversed out of the blank liner 47 and up the open end 52 of the wash pipe 50 and thence up the passageway 60 and out of the well through the pipe 14 at the well head, not shown.

It may be seen from the foregoing description taken with the drawing that I have devised a novel and useful apparatus for performing squeeze cementing without exerting excessive pressures on the well casing.

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:

1. Apparatus for use in a well casing adapted to be connected to a pipe string which comprises, in combination, an outer mandrel provided with spaced apart first and second ports, an inner sleeve arranged within said outer mandrel and spaced away from said outer mandrel to define therewith an annular passageway communicating with said spaced apart ports, said outer mandrel being adapted to be connected to said pipe string, a packing assembly mounted on said outer `mandrel between said spaced apart ports, means releasably holding said outer mandrel against slidable movement with respect to said packing assembly, said packing assembly being provided with at least one pipe gripping means, a sealing means on said packer assembly for sealing with the wall of the casing, a blank liner, means releasably attaching said blank liner at its upper end to the lower end of said outer mandrel, a cement set shoe attached to the lower end of said blank liner, a wash pipe threadedly attached to the releasable attaching means and arranged within and spaced apart from said blank liner, and packing means on said wash pipe for sealing between said wash pipe and said blank liner against upward ow in said well.

2. Apparatus for use in a well casing adapted to be connected to a pipe string which comprises, in combination, an outer mandrel provided with spaced apart first and second ports, an inner sleeve arranged within and attached to said outer mandrel at tirst and second ends of said sleeve and spaced away from said outer mandrel to define therewith an annular passageway communicating with said spaced apart ports, said outer mandrel being adapted to be connected to said pipe string, a packing assembly mounted on said outer mandrel between said spaced apart ports, means releasably holding said outer mandrel against slidable movement with respect to said packing assembly, said packing assembly being provided with a plurality of pipe gripping means, a sealing means on said packer assembly for sealing with the wall of the well, a blank liner, means releasably attaching said blank liner at its upper end to the lower end of said outer mandrel, a cement set shoe attached to the lower end of said blank liner, a wash pipe threadedly attached to the releasable attaching means and arranged within and spaced apart from said blank liner, and packing means on said wash pipe for sealing between said wash pipe and said blank liner against upward How in said well, said blank liner and said wash pipe being attached to the outer mandrel below said outer mandrel a distance in the range from about 30 to about 300 feet.

3. Apparatus for use in a well casing adapted to be connected to a pipe string which comprises, in combination, an outer mandrel provided with spaced apart iirst and second ports, an inner sleeve arranged within and attached to said outer mandrel a-t first and second ends of said sleeve and spaced away from said outer mandrel to define therewith an annular passageway communicating with said spaced apart ports, said outer mandrel being adapted to be connected to said pipe string, a packing assembly mounted on said outer mandrel between said spaced apart ports, means releasably holding said outer mandrel against slidable movement with respect to said packing assembly, said packing assembly being provided with a plurality of drag springs, a plurality of pipe slips, and a swab cup on said packing assembly for sealing with the wall of the well, a blank liner, means releasably attaching said blank liner at its upper end to the lower end of said outer mandrel, a cement set shoe attached to the lower end of said blank liner, a wash pipe threadedly attached to the releasable attaching means and arranged within and spaced apart from said blank liner, and packing means on said wash pipe for sealing between said wash pipe and said blank liner against upward tlow in said well.

4. Apparatus for use in a well casing adapted to be connected to a pipe string which comprises, in combination, an outer mandrel provided with an internal annular passageway provided with spaced apart rst and second ports communicating the exterior of said mandrel with said internal passageway, said outer mandrel being adapted to be connected to said pipe string, a packing assembly mounted on said outer mandrel between said spaced apart ports, means releasably holding said outer mandrel against slidable movement with respect to said packing assembly, said packing assembly being provided with at least one pipe gripping means, a sealing means on said packing assembly for sealing with the wall of the casing, an elongated conduit attached to the lower end of the outer mandrel below the second of said spaced apart ports, a blank liner, means releasably attaching said blank liner at its upper end to the lower end of said conduit, a cement set shoe attached to the lower end of said blank liner, a wash pipe threadedly attached to 6 the releasable attaching means and arranged within and spaced apart from said blank liner, and packing means on said wash pipe for sealing between said wash pipe and said blank liner against upward flow in said well.

5. Apparatus for use in a well casing adapted to be connected to a pipe string which comprises, in combination, an outer mandrel provided with an internal annular passageway provided with spaced apart rst and second ports communicating the exterior of said mandrel with said internal passageway, said outer mandrel being adapted to be connected to said pipe string, a packing assembly mounted on said outer mandrel between said spaced apart ports, means releasably holding said outer mandrel against slidable movement with respect to said packing assembly, said packing assembly being provided with at least one pipe gripping means, a sealing means on said packing assembly for sealing with the wall of the casing, a blank liner, means releasably attaching said blank liner at its upper end to the lower end of said outer mandrel, a cement set shoe attached to the lower end of said blank liner, a wash pipe threadedly attached to the releasable attaching means and arranged within and spaced apart from said blank liner, and packing means on said Wash pipe for sealing between said wash pipe and said blank liner against upward ilow in said well.

6. Apparatus in accordance with claim 5 in which the releasable attaching means comprises a threaded nut slidably keyed to an inner sleeve attached to the lower end of said mandrel and to the upper end of the wash pipe, said threaded nut threadedly engaging internal threads in the upper end of said blank liner and being released therefrom on rotation of said mandrel relative to said blank liner.

References Cited in the file of this patent UNITED STATES PATENTS 1,839,709 Smith Ian. 5, 1932 2,092,048 Brown Sept. 7, 1937 2,585,706 Ware Feb. 12, 1952