Well packers

Dec. 18, 1962 c. _c. _BROWN 3,068,942

WELL PACKERS

Filed Dec. 7, 1959 4 Sheets-Sheet 1

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Dec. 18, 1962

C. C. BROWN

WELL PACKERS

3,068,942

Filed Dec. 7, 1959

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ArroffNEYs

Dec. 18, 1962 c. c. brown 3,068,942

WELL PACKERS Filed Dec. 7, 1959 4 Sheets-Sheet 3

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Dec. 18, 1962

3,068,942

C. C. BROWN

WELL PACKERS

Filed Dec. 7, 1959

Sheets-Sheet 4

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CICERO C BROWN

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ATTORNEYS

United States Patent Office

3,068,942

Patented Dec. 18, 1962

3,868,942

WELL PACKERS

Cicero C. Brown, 8490 Katy Road, Hosston, Tex.

Filed Dec. 7, 1959, Ser. No. 857,739

Claims. (Cl. 166—198)

This invention relates to new and useful improvements in well packers.

One object of the invention is to provide a well packer which is constructed to efficiently seal with the wall of the open bore, whereby it is not necessary that a pipe or liner be disposed in the bore at the point where the seal is to be effected.

An important object is to provide an improved well packer which has its sealing element so arranged that the external diameter of said element may be greatly increased, as compared to its diameter when in a normal undistorted position, whereby the packer may be lowered through a well pipe having a relatively small bore as compared to the bore in which said packer is finally set; the arrangement assuring maximum annular by-pass around the packer during lowering and effective sealing of the packer with the wall of an open bore which is considerably larger than the bore of the well pipe.

A particular object is to provide a well packer wherein the sealing element is constructed of a plurality of annular sealing rings which are arranged in such relationship to each other that an endwise force applied to the elements results in a co-action between the sealing rings to effect a combined deformation and outward displacement of the rings, whereby the external diameter of the sealing element is greatly increased; the sealing rings not only making possible the maximum increase in the outer diameter but also providing an effective sealing action with the irregular surface of an open formation which renders the packer capable of positive sealing off with the wall surface of said formation.

Another object is to provide an improved well packer having a sealing element which is expansible to greatly increase the outer diameter of the sealing element and which is adapted to be actuated by the application of hydraulic pressure fluid applied through the pipe upon which the packer is lowered.

A still further object is to provide a packer which is particularly adapted for use in water flooding operations but which could be employed as a production packer; said packer lending itself to use as a single packer or to use in combination with another packer or packers in multiple production wells.

The construction designed to carry out the invention will be hereinafter described, together with other features thereof.

The invention will be more readily understood from a reading of the following specification and by reference to the accompanying drawings forming a part thereof, wherein an example of the invention is shown, and wherein:

FIGURE 1 is a view, partly in section and partly in elevation, of a well packer constructed in accordance with the invention and illustrating the packer in its normal undistorted position;

FIGURE 2 is a similar view with the sealing element of the packer expanded into sealing position;

FIGURE 3 is an elevation of the improved well packer disposed within a well bore and showing the packer combined with another packer to separate two formations traversed by the same bore;

FIGURE 4 is an enlarged view, partly in section and partly in elevation, of the flow control assembly at the upper end of the apparatus shown in FIGURE 3;

FIGURE 5 is an enlarged view, partly in section and partly in elevation, of the connection between the well packer and the well pipe;

FIGURE 6 is a view, partly in section and partly in elevation, of one type of packer which may be combined with the improved well packer in the manner shown in FIGURE 3, and

FIGURE 7 is an enlarged partial section of the preferred means for holding the sealing element in the expanded sealing position.

In the drawings, the numeral 10 designates an elongate tubular support or mandrel having an axial bore 11 extending entirely therethrough. A sealing element, generally indicated at A, which will be hereinafter described in detail, surrounds the major portion of the exterior of the mandrel (FIGURE 1) and has its upper end confined by segmental retaining elements 12. Each retaining element is formed with a hook portion 13 which is engageable within an annular groove 14 of the upper coupling 15 whereby each element is capable of an outward swing or pivotal movement. The coupling 15 is threaded onto the upper end of the mandrel or support and extending upwardly from the coupling is a coupling sleeve 16. The sleeve has a releasable connection, through a coupling unit C, with the well pipe P on which the packer is mounted.

The lower end of the sealing element A is confined by a plurality of lower segmental retaining elements 12« which are similar in construction to the upper retaining elements 12. Each of the lower retaining elements is formed with a hook portion 17 engageable within an annular internal groove 18 of a collar 19 to mount the elements for outward swinging movement. The collar 19 encircles the mandrel, being slidable relative thereto, and is threaded into the upper end of an elongate cylinder 20, which cylinder extends downwardly below the lower end of the mandrel. The lower end of the cylinder has a perforated inlet plug 20« secured thereto.

Hie annular space or area S between the cylinder 20 and the external lower portion of the mandrel has its upper end closed by the collar 19 while its lower end is closed by an annular sealing collar or block 21 which is threaded onto the lower end of said mandrel. A suitable sealing ring 22 seals between the exterior of the block 21 and the inner wall of the cylinder 20 while a similar sealing ring 23 prevents leakage past the threaded joint between the block and the mandrel. The sealing block 21 has an axial bore 24 extending therethrough with an inclined valve seat 25 at the upper end of this bore.

For establishing communication between the bore 11 on the mandrel or support and the space S to permit introduction of fluid pressure from the bore of the mandrel into said space, a plurality of radial ports 26 extend through the wall of the mandrel and are located above the annular sealing block 21. An annular piston 27 which encircles and is slidable upon the mandrel is located within the annular space S in abutting relationship to the lower end of the collar 19 which closes the upper end of the cylinder. Sealing rings 28 on the annular piston 27 seal with the internal wall of the cylinder and the exterior of the mandrel or support. Normally the piston is detachably secured to the mandrel or support in the position shown in FIGURE 1 by means of a frangible shear pin 29.

When the packer device is to be employed with a single pipe string, said device is connected to the pipe string indicated at P by the releasable coupling unit C. The coupling unit C (FIGURE 5) includes a housing 32 having a depending skirt portion 33 which is adapted to encircle the upper end of the sleeve 16 extending upwardly from the mandrel. A suitable sealing ring 34 seals off between the housing and sleeve. A pair of diametrically opposed J-slots 35 are formed within the skirt portion 33 and

3,068,942 these slots are adapted to co-act v/ith coupling pins 35α which project radially from the sleeve 16, whereby the housing 32 is releasably connected to the sleeve 16 at the upper end of the packer device. As has been noted, well pipe P is connected to the housing 32.

The elongate sealing element A, which extends substantially throughout the length of the mandrel when in its normal undistorted position, is constructed of a series of upper sealing rings 37 and a series of lower sealing rings 33. A pair of central separator and sealing rings 39 and 39α separate the upper sealing rings from the lower sealing rings. The rings 37, 38, 39 and 39α are constructed of an elastic or deformable material such as rubber, rubber compound or the like.

As clearly shown in FIGURE 1, the upper and lower surfaces 370 and 37α, respectively, of each of the upper series of sealing rings 37 are inclined downwardly and outwardly with respect to the mandrel or support 10. The rings nest one within the other with the lower inclined surface 37α of each ring engaging the complementary inclined upper surface 37b of the ring therebelow. When in a normal undistorted position, the outer periphery 37c of each ring is substantially straight and is in a plane parallel to the axis of the support.

The lowermost ring 37 of the upper series of rings has its lower downwardly and outwardly inclined surface 37α engaging the upper downwardly and outwardly inclined surface 39b of the separator ring 39. The lower end of the separator ring is substantially flat and lies in a plane normal to the axis of the support, said ring being in engagement with the complementary flat upper surface of the separator ring 39α. Ring 39α has its lower surface 39c inclined downwardly and inwardly with respect to the support. The outer peripheries 39d of rings 39 and 39α lie in substantially the same plane as the outer peripheries of the upper sealing rings when the rings are in a normal undistorted position. If desired, the separator rings 39 and 39α may be integral so that only a single separator ring having upper and lower inclined surfaces 39b and 39c would be provided.

The lower series of sealing rings 38 are of substantially the same construction as the upper series of rings 37 except that they are inverted; such inverting directs the lower series of rings upwardly and outwardly with respect to the support. The rings 38 are nested in overlapping relationship with the lower upwardly and outwardly inclined surface 38α of each ring engaging the upper upwardly and outwardly inclined surface 38Z&gt; of the next below ring. The uppermost ring 38 of the lower series of rings has its upper surface contacting the upwardly and outwardly inclined surface 39c of the separator ring 39α. The lowermost ring 38 is confined by the retaining elements 12α and the outer peripheries 38c of the rings 38 lie in the same plane as the peripheries of the upper rings 37 of the separator rings when in the normal undistorted position shown in FIGURE 1.

When in their normal position, the rings of the sealing element overlie substantially the major portion or length of the mandrel or support. At such time the external diameter of the sealing element is at a minimum so that as the device is lowered within the well pipe or bore, a substantial by-pass area around the device is obtained.

For effecting a setting of the sealing element A to expand the sealing rings thereof into sealing engagement v/ith the wall of the well bore, a suitable closure or plug B (FIGURE 1) is dropped or pumped dov/nwardly through the well pipe P and passes downwardly through the bore 11 of the mandrel to seat upon the annular seat 25 which is at a point below the radial ports 26 in the mandrel. It will be appreciated that the closure B may be any one of the well-known types, such as a retrievable plug as shown in FIG. 1, or a ball. Thereafter, a fluid pressure is applied within the pipe P and bore of the mandrel and such fluid pressure is directed through ports 26 into the annular space or chamber S, its force being directed against the lower end of the annular piston 27. The pressure is built up sufficiently to shear the pin 29 and thereafter the piston moves upwardly along the mandrel or support. Since the piston 27 is engaged with the under side of the collar 19 which is, in turn, closing the upper end of the cylinder 20, the piston, collar and cylinder move upwardly relative to the mandrel until the parts reach the position shown in FIGURE 2. Since the upper end of the sealing element is held stationary by reason of the collar 15 being attached to the mandrel, the upward movement of the piston and collar applies an endwise compressive force to the sealing element A. This endwise compressive force moves the lower collar 19 toward the upper collar 15 and causes the engaged inclined surfaces of the sealing rings 37 and 38 to co-act with each other. Because of this co-action between the engaging inclined surfaces of the sealing rings, said sealing rings are first flared or moved in a radially outward direction and are then further deformed until they assume the position which is illustrated in FIGURE 2. The outward swinging movement of the sealing rings is permitted because the segmental retaining elements 12 and 12α at the ends of the sealing element A may swing outwardly on their respective pivotal connections. Thus the outer peripheral edges of the sealing rings 37 and 38 are moved toward the wall of the well bore and function to make a sealing contact therewith. Because a plurality of the rings are provided, the sealing elements engage the wall at spaced points and even though the wall may be somewhat uneven or irregular as might be the case with the open formation, an effective seal with the wall may be obtained. Therefore, the necessity of setting a casing or a liner within which the packer must be set is obviated.

In addition to providing an efficient seal, even though the wall of the bore might be uneven and irregular, the arrangement of the plurality of superposed sealing rings permits the outer diameter of the sealing element to be greatly increased as compared to its normal diameter. There is an actual swinging motion of each sealing ring and it is this outward flaring or swinging of each ring which makes it possible to obtain a much greater outer diameter of the sealing element than would be possible in the usual type of solid sleeve-type sealing element.

To maintain the sealing elements in their expanded or sealing position, the bore of the lower collar 19 is formed with an annular recess 40 having an outwardly and downwardly inclined or tapered wall as best seen in FIGURE 7. An annular, split gripping slip element 41, having its teeth directed so as to prevent downward movement of the collar 19 relative to the mandrel, is mounted within said recess 40. After the sealing rings of the element A have moved into their expanded or sealing position, any tendency of collar 19 to move downwardly is prevented by the slip element 41 which engages the exterior surface of the mandrel or support. A force tending to move the collar 19 downwardly relative to the mandrel 10 will move the gripping element 41 into tighter engagement with the mandrel through the coaction of the surface 416 on the gripping element 41 with the outwardly and downwardly inclined wall at the recess 40.

. The packer is of the permanent type which, after being set, remains in position sealing the annular space between the mandrel of the assembly and the wall of the well bore.

The packer has been found particularly adaptable for use in water flooding operations where it is desirable to seal within the open bore below the usual well casing. Water pumped downwardly through the pipe P and mandrel is discharged through the openings in the plug 20α at the lower end of the cylinder. The closure B shown in FIG. 1 is of the well-known plug type adapted for retrieving and removal through the use of a wireline, and it is understood that the closure B would be removed after the packer is set and prior to the start

3,068,942 of the water flooding operation. The packer may also be employed as a production packer to seal off the well bore above a particular producing formation. In such case, the well fluids enter through openings in the plug 20α and are conducted to the surface through the well pipe P.

The particular packer shown has also found application in dual production or in the water flooding of dual formations. In such event, the packer is combined with an upper packer indicated at D in FIGURE 3. In this case, the mandrel or support 10 having the sealing element A thereon is run into the well by means of the pipe P in the manner shown in FIGURE 1. Thereafter, the closure or plug B is positioned and pressure fluid applied the the annular piston 27 as above described to effect a setting of the packer. Thereafter, the housing 32 and the pipe P are disconnected from the packer leaving the same within the well bore in its set position.

An outer well pipe Pl is then lowered within the well bore and this assembly has the packer D mounted in the proper position thereon. The lower end of the pipe Pl has a sleeve 50 provided with inlet ports 51 threaded thereon, said sleeve being connected between said pipe and the housing 32 of the coupling unit G. When the housing 32 of said unit is reconnected with the connecting pins 35α of the sleeve 16 in the manner shown in the upper portion of FIGURE 2, the fluid above the set packer may enter the ports 51 and flow upwardly through the outer pipe Pl. .. After pipe Pl is in position, an inner pipe P2 is adapted to be run within the outer pipe. The lower end of the inner pipe has a latch assembly secured thereto and said assembly includes latches 54 which engage an annular recess 55 provided within the sleeve 16. Thus, after said inner pipe is run, it is suitably latched in position.

Both of the pipes Pl and P2 extend to the surface of the well and are supported in a tubing head 52. With the packer D in set position, it will be evident that the fluid between the packers may enter ports 51 and be conducted to the surface through the outer pipe Pl. Fluid from the area below the sealing elements A of the lower packer enters the perforated plug 20α, flows upwardly through the mandrel 10 and into the bore of the inner pipe P2 which conducts it to the surface. Pipe P2 is connected to an outlet line 53 having a suitable valve 56 therein (FIGURE 4) while the upper end of the outer pipe Pl has connection with an outlet pipe 57 which may also have a control valve (not shown) mounted therein.

As illustrated in FIGURE 3, the area between the packers communicates with an upper formation Fl while the area below the lower packer communicates with a second formation F2. Although any desired type of packer may be employed as the upper packer D, one type of packer which has been found satisfactory is illustrated in FIGURE 6. This packer includes a tubular supporting mandrel 60 which has its lower end connected in the outer pipe Pl. An upwardly directed sealing member 61 and a downwardly directed sealing member 62 are mounted on the mandrel 60 and these sealing elements are adapted to be moved outwardly into sealing position by the pressure differential across the packer. Suitable gripping slips 63 may be embedded in the outer surface of a portion of the sealing elements whereby outward distortion of the elements into sealing position will also set the slips.

The upper end of the mandrel 60 has connection with a tubular sleeve member 64 which is provided with by-pass ports 65. Connected to the sleeve 64 by coarse righthand threads 66 is an internal tubular element 67. This element is formed with a port or ports 68 which co-act with the ports 65 in the sleeve. The upper end of the tubular element 67 is also connected in the upper portion of the outer string Pl. When the packer shown in FIGURE 6 is being lowered into the hole, the tubular element 67 is in the position shown with respect to the sleeve 64 whereby the ports 68 and 65 are in registration. Thus, a by-pass of fluid around the sealing elements 61 and 62 of the packer may occur, with flow passing through ports 51, the annular space between Pl and P2, and outwardly through aligned ports 65 and 68. After the lower end of pipe Pl has been coupled to the mandrel 1® Of the lower packer, said pipe is rotated to move the tubular element 67 downwardly relative to sleeve 64 to misalign the ports 65 and 68 to close bow therethrough. The inner pipe P2 may be lowered into position after the outer pipe Pl has been connected to the lower packer. Said inner pipe is lowered through the bore of the outer pipe and when its latch assembly L moves into the upwardly extending sleeve 16 which projects upwardly from mandrel 10, the latches 54 engage the recess 55 to latch the lower end of the inner pipe in position. Suitable packing 54α on the latch assembly L seals off between the latch and the sleeve 16 to assure that flow will be upwardly from the mandrel 10 and through the inner pipe P2.

When used in either dual production or for the purpose of establishing communication with two formations, the packer of the present invention may have its sealing element A set at a point below the well casing since it is capable of sealing with the open formation of the well bore. The upper packer D may set within the casing or pipe of the well and thus one packer which is of usual construction is within the casing and the improved packer of this invention is within the open bore. The provision of the plurality of sleeves which make up the sealing element assures that the external diameter of the packer is sufficiently small to readily move downwardly through the casing or pipe within the well bore and into position below said casing or pipe. Thereafter, the expansion of the sealing element may be accomplished and because of the plurality of sealing rings and their swinging motion, the external diameter of the sealing element A may be greatly increased.

The foregoing disclosure and description of the invention is illustrative and explanatory thereof and various changes in the size, shape and materials, as well as in the details of the illustrated construction, may be made within the scope of the appended claims without departing from the spirit of the invention.