US3215206A - Dual string packer construction - Google Patents

Description

M. L. cRow 3,215,206

5 Sheets-Sheet 1 ATTORNEY Nov. 2, 1965 DUAL STRING PACKER CONSTRUCTION Filed July 26. 1961 5 Sheets-Sheet 2 I-1 INVENTOR Morgan L. Crow ATTORNEY M. L. CROW DUAL STRING PACKER CONSTRUCTION m EL @d U M, vlv

Nov. 2, 1965 Filed July 26. 1961 Nov. 2, 1965 M. L. CROW DUAL. STRING PCKER CONSTRUCTION 5 Sheets-Sheet 3 Filed July 26. 1961 INVENTOR Morgo n L. Crow ATTORNEY Nov. 2, 1965 M. L. cRow DUAL STRING PACKER CONSTRUCTION 5 Sheets-Sheet 4 Filed July 26. 1961 INVENTOR Morgan L. Crow ATTORNEY Nov. 2, 1965 M. L. CROW DUAL STRING` PNCKER CONSTRUCTION 5 Sheets-Sheet 5 Filed July 26, 1961 BY Mw ATTORNEY gealed well fluids, or the like. Ations are encountered while the dual packer is being United States Patent() 3,215,206 DUAL STRING PACKER CONSTRUCTION Morgan L. Crow, Dallas, Tex., assignor, by mesne assignments, to Dresser Industries, Inc., Dallas County, Tex., a corporationl of Delaware Filed July 26, 1961, Ser. No. 126,999 13 Claims. '(Cl. 166-120) This invention is concerned with a well packer, and is particularly concerned with a packer for packing and sealing about dual strings of tubing extending into a well bore.

In oil or gas wells having two zones of production 1ocated at different vertical levels, it is required by state regulatory bodies, in the interest of conservation, that the two zones be separated, and produced through separate conduits.

One means of separately producing the two zones, which has been practiced in the past, is to set a packer between the zones, and produce the lower zone through a tubing attached to the packer and extending to the surface, and `the upper zone through the tubing-casing annulus above the packer.

This system has been fraught with certain dii'liculties in that the production through the larger cross-sectional area of the tubing-casing annulus resulted in less efficient flow of fluid in that the zone pressure required to lift the iluid must be greater, and in many instances was insuilicient to lift the fluid.

Another shortcoming of such system is that the casing is subjected to corrosive and erosive action of the iluid.

Another system of production of fluid from dual zones comprises the setting of a packer between the zones, and the setting of a dual packer, having two longitudinal passages therethrough above the upper zone,'with the lower zone communicating through the lower packer with one passage in the dual packer, and with a string of tubing extending to the surface, and the upper zone communicating with the other passage through the packer and the tubing -string extending to the surface.

By the employment of such system both zones of production are caused to flow through tubing strings. The casing is thereby protected from corrosive and erosive action, and more ecient fluid ow results from the upper zone due to lessening the surface and the cross-sectional area through which the upper zone must flow.

This invention is concerned with improvements in a dual packer employed in the practice of such secondnamed system of dual zone well completion.

The dual packer hereinafter described has the following advantages, and .accomplishes the following novel 'objectives over previous types of dual packers employed in the practice of such system, to-wit:

The packer which is the subject of this invention is set by the second string of tubing only, and thereby eliminates the hazards of premature setting of the packer while being lowered into the hole by encountering debris, con- In the event any obstruclowered into the casing, the packer -may be pushed and rotated safely through such obstructions without the danger of prematurely setting the packer.

The weight set on the rst packer, which is run and set .between the zones. of production before running and lCe setting the dual packer, may be accurately controlled, inasmuch as the primary string which is -run into the hole and attached to the rst packer is not affected when the dual packer is set, because only the relatively low force required to unlatch the dual packer is transmitted to the primary string of tubing. The greater force required to compress the rubber is supported by the expander head which causes the wedged slips to grip the inner side of the casing.

Therefore, the tubing weight of the primary string is substantially the only weight exerted on the iirst packer, and the tubing weight of the primary string may be designed exactly for the -completion technique involved and the pressures anticipated.

The primary string may be freely rotated through the packer to set any type of packer therebelow. For instance, it may be rotated to release the J-slot in a hook wall packer, or engage or release a latch stinger in a drillable packer, permitting disengagement or re-engagement of the primary string from the lower packer for workover operations.

The packer may be unseated and reset repeatedly, as desired, by simply pulling up and lowering the secondary string.

If for any reason 4the packer does not retract and release by pull upon the secondary string, a safety release device is built into the packer to release and relax the packer by picking up on the primary string. When the primary string, and mandrel attached thereto, is picked up, shear pins connecting the mandrel with the slip support housing are broken to allow the slips to move downwardly with reference to the expander head therefor and thereby relax the packer. After the packer has been relaxed the primary string may be rotated through the packer to screw the primary string out of the lower packer and pick the dual packer up out of the hole by means of inter-engaging shoulders between the primary mandrel and the packer. e Y 'v In setting the packer by downward force exerted upon the secondary string, no force is transmitted through the emergency release shear pins, as in previous type packers of this character. In vthe packer construction herein described and claimed, the compressive setting load is imposed upon the packer through the anchor body above the packer, and directly to the latch, attaching the packer body tothe primary mandrel, to release same, and is thence transmitted to the primary mandrel. `In such procedure the unlatching load for releasing the packer body from the primary mandrel is never imposed on the emergency release shear pins. If the emergency release shear pins are -sheared out before the packer is set, the packer is rendered unsettable, making it necessary to withdraw the packer from the hole. In applicants construction such could not occur, because the unlatching load is never imposed upon the shear pins.

In my packer construction the expander ring, for releasing the packer body from the primary mandrel, to allow relative downward movement therebetween, serves a dual function in that it also acts as a pickup shoulder, engageable with a shoulder inside the packer body, to lift the packerout of the hole upon emergency release.

A`novel bayonet type coupling is provided between sections of the packer assembly, including the connection between the upper and lower support members ofthe packer sleeve, the shea-r pin housing disposed thereabove, and the slip expander head exposed therebelow. Such bayonet type connection includes inter-fitting male and female members, which are inter-engage-d by relative rotation, and when parallel pipes are extended through openings therein, positively locks same against counter-rotation for disengagement. This principle may be utilized in other well applications, where elements are to be connected together and multiple pipes or strings are to be extended therethrough, eliminating the necessity for the threaded connections.

The longitudinal passages for the multiple pipes or strings also provide the vacancies in the male and female bayonet members through which the male and female members may be aligned and then rotated to achieve full engagement.

rIn such novel packer construction the coupling between the mandrel sections of the primary string is so arranged in length as to keep the latch expanded when upward pull is exerted on the primary string for shearing out and picking up under emergency conditions, thereby preventing the latch from becoming engaged with the body of the packer before the mandrel has been pulled up suiciently in the body to allow shea-ring of the shear pins, and engagement of the pick up shoulder on the mandrel with the pick up shoulder in the body.

This construction also facilitates the normal unseating and reseating operations with a maximum of relia-bility because the latch does not relax and re-expand while the packer is in the set position.

In such packer construction, a hydraulically actuated slip arrangement is provided, actuated by pressure from bel-ow the packer, which permits the packer to hold against pressure from above or below. Thereby the packer remains in set condition, even though the pressure below the packer is greater than that above, as when gas lift installations or fracturing operations are employed.

Other and further objects of the invention will become apparent upon reading the detailed specification hereinafter following, and by referring to the drawings annexed hereto.

A suitable embodiment of the invention is shown in the attached drawing wherein:

FIGURE I is a side elevational view of the dual packer assembly in unset condition;

FIGURE II is a side elevational view of the dual packer assembly with the packer in set condition;

FIGURE III is a diagrammatic, cross-sectional, elevational view showing the dual packer-inset condition in a well, with a drillable packer seated tlerebelow between two zones of production in a well;

FIGURES IV, IVA and IVB are cross-sectional, elevational views of the dual packe-r assembly attached to the primary string, with the packer in relaxed position, as -it would appear while being lowered into the well, and prior to, Vor after, the setting of the lower packer (not shown);

FIGURE V is a transverse, cross-sectional View taken on the line V-V of FIG. IV, showing two oppositely disposed hydraulic pistons, with passages communicating with the rear thereof from the secondary passage;

FIGURES VI and VIA are cross-sectional, elevational views of the packer assembly taken on the line VI-VI of FIGURES IV, IVA and-IVB;

FIGURE VII is a transverse, cross-sectional view taken on the line VII-VII of FIG. IV;

FIGURE VIII is a transverse, cross-sectional view taken on the line VIII- VIII of FIGURE IVA;

FIGURE IX is a transverse, cross-sectional View taken on the line IX-IX of FIGURE IVA;

FIGURE X is a transverse, cross-sectional View taken `Orl the line X-X of FIGURE IVA;

FIGURE XI is a transverse, cross-sectional View taken on the line XI-XI of FIGURE IVB;

FIGURES XII, XIIA and XIIB are a cross-sectional,

l elevational view similar to FGURES IV, IVA and IVB, showing the dual packer assembly as it appears in set condition, with the secondary string attached thereto;

FIGURE XIII is a transverse, cross-sectional view taken on the line XIII-XIII of FIGURE XII;

FGURES XIV and XIVA are a cross-sectional, elevational view of the packer assembly, similar to FIGURES VI and VIA, showing the packer assembly in set condition;

FIGURE XV is a transverse, cross-sectional view taken on the line XV-XV of FIGURE IVB; and

FIGURE XVI is a perspective exploded view of the latch spring housing and the upper packer support, illustrating the bayonet connection between such two members.

Numeral references are employed to designate the various parts shown in the drawings, and like numerals indicate like parts throughout the various figures of the drawings.

FIGURE III is a schematic representation of the packer and tubing arrangement employed with the dual string packer of the type herein described, as it would appear when set in the casing.

The numeral 1 indicates a well casing which extends into a well bore from the earths surface.

The dual packer body is generally indicated at 2, which has a packer sleeve 3 of resilient material disposed thereabout, which is compressed and expanded into sealing engagement with the inner wall of the casing 1. The packer assembly is anchored to the casing wall by means of toothed slips 4, the teeth on which are forced against the casing wall in penetrating engagement therewith.

The body 2. has two parallel, longitudinal passages 5 and -6 therethrough.

A tubular member 7, which usually includes a mandrel with a tubing string attached at the upper and lower ends thereof, extends through the passa-ge 5. Such tubular member 7 communicates, through a tubing string, extending therethrough, with the earths surface and is attached at its lower end to a tubing string which in turn is attached in the bore of a lower packer 8.

The packer 8 is of the drillable type which may be run and set either on a tubing string or on a wire line and expanded by pressure uid released therein or by mechanical force. The packer body 8 is anchored to the casing wall 1 by means of upper toothed slips 9 and lower toothed slips 10, and has extended thereabout a resilient packer sleeve 11, which is expanded into sealing engagement with the wall of casing 1.

Tubing string 7 below the dual packer may be disengageably attached to the packer body 8 in communication with the passage therethrough by means of a stinger 9a which may be latched or threaded thereinto. As previously explained, the tubing string 7 is arranged to rotate in the packer body 2, to permit the stinger 9a to be rotated, when necessary, into and out of threaded engagement with the packer body 8.

A packing nipple or connection 12 is attached in the passage through the packer body 8 and may be attached at its lower end to a screen pipe, standing valve or other contrivance which permits production fluid to pass through the passage through the packer body 8 and upwardly through the tubing string 7.

A stinger 13, attached to the lower end of a secondary string of tubing 20, extending to the earths surface, has an expandable split ring 15 disposed thereabout which is arranged to be contracted, and allowed to expand outwardly into an annular recess 14 in the upper end of the passage 6 to disengageably latch the stinger 13 in communication with the passage 6, and thereby disengageably latch the secondary tubing string 20 to the packer body 2, so that downward force may be exerted through the secondary tubing string 20 upon the packer body 2, to unlatch the body from the mandrel of the primary string 7 to permit the packer body to be moved downwardly over the primary mandrel and expand and set the packer against the casing wall, in the manner which will be hereinafter described.

A suitable seal 16 is arranged about the lower end of the stinger 13 to provide a seal between the outer wall of the stinger and the inner wall of the passage 6.

The upper end of the body 2, about the passage 6, comprises a landing scoop 17, which has an inwardly converging entry surface thereabout to guide the stinger 13 into the landing scoop 17.

The lower packer 8 may be rst run into the well and set above a lower zone of production at a suitable elevation. The primary string of tubing is then made up and run into the well, with the dual packer 2 in suitable spaced relationship above the lower packer 8. Before the upper dual packer is set the stinger 9a is guided into and latched in the lower packer 8. The string of tubing 7 may be rotated, if desired, through the upper packer 2 to engage and dsengage the stinger 9a with the lower packer.

The upper packer 2 is so spaced from the lower packer 8, that the upper packer is disposed above an upper Zone of production which communicates with the tubing casing annulus in the area indicated at 19 through perforations 19a.

To set the upper packer 2, the secondary string 20 is made up and run into the well with the stinger 13 attached to the lower end thereof. The stinger 13 is guided into the landing scoop 17 and locked therein, and downward force is exerted through the secondary string 20 upon the packer body 2, to thereby force the body downwardly over the mandrel of pipe 7, extending through the primary passage of the body 2 to thereby unlatch the body 2 from the primary mandrel of tubing 7, and allow the body 2 to be moved downwardly over the primary mandrel to expand the slips 4 into engagement with the casing and expand and seal the resilient sleeve 3 against the wall of the casing by increased downward force exerted upon secondary string 20.

It will be seen that when the packers 8 and 2 are set in the well, the tubing string 7 communicates with a lower zone of production below the packer 8 and the tubing 'string 20 communicates with an upper zone through the passage 6 extending through the packer 2.

The foregoing is a general description of the purpose, operation and function of the packer apparatus herein described for dual completions, and the following is a detailed description of the specific apparatus for constructing and operating the novel dual packer.

FIGURE I shows the dual packer assembly as it would appear while being lowered into the casing on the string of tubing 21, and before it is set in the casing. FIGURE II shows the packer assembly as it would appear in the casing string, after the stinger 13 has been lowered into the casing on the string of tubing 20, latched into the body of the packer, and force has been exerted downwardly on the packer body through tubing 20, to unlatch same from the mandrel of tubular member 7 to move the packer body downwardly over the mandrel, to expand the slips into anchoring engagement with the casing, and expand the resilient seal member, about the packer, into sealing engagement with the casing.

The assembly, as shown in these drawings, includes the landing scoop 17 attached to the anchor body 22 by cap screws 84 (FIG. XIII).

The anchor body 22 and the landing scoop 17 have parallel aligned passages therethrough forming portions of the passages 5 and 6, hereinbefore indicated.

Auxiliary piston slips 23 may be disposed in passages provided in the wall of the anchor body 22, and are arranged to move outwardly in response to pressure from .below the dual packer device in the manner hereinafter yto the outer surface of the body Z2 and extending through aligned vertical slots provided in the outer face of the 6 piston slips 3, in the manner hereinafter described in more detail.

The latch spring housing 25 has parallel vertical passages therein, in alignment with the passages through `the landing scoop 17 and anchor body 22, and is connected to the anchor body 22 by means of bolts 54 extending through counter-sunk passages 53, and threadedly engaged in holes 55 in the lower face of the anchor `body 22, as indicated at 55 (see FIG. XIV).

The packer sleeve, generally indicated at 3, is preferably made up of a plurality of superposed discs or segments 26 made of resilient material, such as rubber or synthetic rubber material, and have parallel passages therethrough arranged to receive the mandrels or tubular members extending through the packer device.

The resilient segments 26 are disposed between disclike support members 27 and 28. The upper support disc 27 is attached to the latch spring housing by a bayonet connection, which will be described in more detail hereinafter, and the lower disc support member 28 is attached to the slip expander head 29 by a similar bayonet type connection.

The slip expander head 29 is suspended on a shoulder 477 provided on the -secondary mandrel 76 (FIG.

'mandrel section 42, extending through the packer body,

by means of shear screws 30a (FIG. XI). The shear screws 30a have inner ends which are engaged in a recess on a shoulder 32 provided about the mandrel section 42, and such inner ends are weakened so that they may be broken to release the slip supporting housing v30 from the mandrel 42 upon exertion of a predetermined force thereon.

An adjusting sleeve 33 is -threadedly engaged in the lower end of the slip supporting housing 30, and is arranged to engage a shoulder 82 provided about the lower mandrel section 42 to provide for proper adjusted relationship between the mandrel and the other parts of the packer. After the adjusting sleeve 33 has been positioned in proper adjusted relationship against the shoulder 82, it may be fixed in place by set screws 33a extending through the wall of the housing 30.

The toothed slips 31 are slidably connected to the tapered surfaces 29a on the expander head 29 by means of dovetail connections indicated at 35 (FIG. 1X).

The slips 31 are slidably connected at their lower ends to mounting lug 37 by interengaging slots 36 provided between the upper ends of the mounting lugs 37 and the lower ends of the slips 31. The lugs 37 are attached to opposed flat recessed surfaces on the slip support housing 30 by means of cap screws 38.

The mandrel section 42 is attached to the tubing string extending below the dual packer 2 by means of a conventional coupling 39 and the upper end of the mandrel 7 is attached to the tubing string 21, extending above the packer assembly, by means of a conventional coupling 40.

- Referring to FIGURES IV-IVB, the primary mandrel or tubular member 7, passing through the packer 2, is divided into two sections, an upper section 41 and a lower section 42, connected by a coupling 43.

An expander ring 44 is secured about the lower end of the mandrel section 41, and is positioned between an annular shoulder provided about the mandrel section 41 and the upper end of the coupling 43. Said expander head 44 has a tapered surface 45 about the upper, outer end thereof, for the purpose of guiding and expanding extends about the mandrel section 41.

the latch ring 47 thereover, in the manner hereinafter described.

An annular recess 46 is provided in the upper end of the primary bore extending through the latch housing .25 in which is disposed the split spring latch 47, which It will be noted that the spring latch 47, in relaxed position as shown lin FIG. 1V, is engaged between the lower end 49 of the anchor body 22 and the upper end of expander ring 44 to thereby disengageably suspend the body to the primary mandrel 41-42.

An annular shoulder 50 is provided in the lower end of lthe latch spring housing 25 against which the lower end of the coupling 43 is positioned to limit downward movement of the mandrel 7 with reference to the body of the packer assembly, to permit the packer to be retrieved from the hole upon relaxing the packer and pulling upwardly on the secondary string 20.

An annular pickup shoulder 51 is provided inside the anchor body 22 which is engageable with the expander ring 44 to permit the packer device to be picked up and withdrawn from the hole on the primary string 21 upon emergency release procedure hereinafter described.

It will be seen that when force is exerted downwardly upon the packer body by the secondary string in the manner hereinafter described, the packer body 2 is caused to move downwardly and the tapered surface 48 on the inner side of the lower end of the spring latch ring 47 engages the tapered surface 45 on the upper, outer end of the expander ring 44, expanding the latch spring 47 outwardly into the recess 46, to unlatch the packer body from the primary mandrel 7, to thereby allow the packer body 2 to move downwardly with reference to the primary mandrel to expand the packer sleeve 3.

The initial downward movement of the packer housing 2 over the primary mandrel 7, moves the expander head 29 downwardly, causing the outward movement of the slips 31 into anchoring engagement with the casing 1, and further downward movement thereof expands the packer sleeve 3 between the packer support rings 27 and 28 into sealing engagement with the casing.

An auxiliary anchoring means is provided by the hydraulically actuated piston slips 23 which are mounted in appropriate sockets 56 provided in the outer wall of the anchor housing 22.

The piston slips 23 have teeth 57 on the outer surfaces thereof, and are provided with seal rings 5S extending thereabout which slidably seal against the inner walls of the sockets 56.

.Inter-communication is provided between the sockets 56 at the rear of the pistons 23 by means of passages 59, which passages are in communication with pressure ports 60 (FIG. V) extending through the anchor body wall and communicating with the longitudinal bore 6 through the packer body.

It will be seen that pressure from below the packer in the annular space 19 will be transmitted through the bore 6 and through the ports 60 and passages 59 to the rear of the piston slips 23, to cause them to move outwardly into anchoring engagement with the casing wall.

The straps 24 extend through vertical slots in the face of the piston teeth, said straps being attached to the outer wall of the anchor housing 22 by means of suitable screws 61.

Springs 24a are disposed in recesses provided in the outer faces of pistons 23 and the outer ends thereof are positioned against the straps 24, to normally urge the piston teeth inwardly of the sockets 56, so as to normally maintain the pistons in said recesses when no pressure is exerted against the rear sides thereof.

It will be seen that the greater the pressure exerted from below the packer through the bore 6, the greater the anchoring force will be exerted against the piston slips 23 to prevent the packer from being moved upwardly and unseated by pressure from below. The slips 31 anchor the packer device against movement in response to downward pressure. The packer device is lthus positively anchored against both upward and downward pressure.

A novel bayonet joint connection is provided between the packer support rings 27 and 28 and the respective members to which they are attached.

As shown in FIG. XVI, the support ring 27 has dual passages 67 and 68 therethrough arranged to receive the secondary mandrel 76 and the primary mandrel section 42, respectively.

Disposed on the upper face of the support ring 27 is a male bayonet pin member 62, having opposed radiused ends thereon, with slots 63 provided thereabout. The radiused ends of member 62 are arranged to be inserted in the cylindrical passages 65 and 66 in the lower end of the latch housing 25 until the ribs 62a provided by the slots 63 come into alignment with corresponding slots 64 in the inner end of the latch housing 25, whereupon the support ring 27 may be rotated to cause the ribs 62a to enter the slots 64 and to bring the passages 67 and 68 into alignment with the passages 65 and 66 through the latch housing 25. The mandrels 76 and 42 may then be extended through the aligned passages 67, 68, 65 and 66, to prevent relative rotation and thereby lock the elements 25 and 27 together against disengagement until the mandrels are removed from such passages. This provides a quick and simple means of assembly of parts in multiple packer devices and in similar equipment without the use of bolts or screws -or threads, and provides a positive means for engagement, and ease in disengagement when it is necessary to disassemble these parts.

The lower support ring 28 is attached to the expander head 29 by the same type of bayonet joint connection as hereinbefore described, wherein the female groove is indicated at 69 and the male rib is indicated at 70, providing such bayonet type connection.

The secondary passage through the packer body 2 includes a tubular mandrel 76 extending therethrough which is threadedly engaged at its upper end to the anchor housing 22, and includes an annular pickup shoulder 77 thereon, which is engageable with an annular shoulder 78 inside the expander head 29, to suspend the expander head thereto and to provide a means for picking up the expander head when the packer is retrieved from the casing.

The stinger 13 includes a coupling head 71 having an annular shoulder 74 thereon engageable with a corresponding shoulder 74a, provided about the upper end of the secondary passage in the landing scoop 17.

The coupling head 71 is threadedly engaged to a spacer tube 72, which in turn is connected to the secondary tublng str1ng above the packer by means of a conventional coupling 73.

A seal tube 75, having seal rings 16 disposed thereabout, is threadedly engaged to head 71 and may be inserted into the secondary bore of the landing scoop 17 1n order to seal between the stinger device and such bore. An O ring seal S5 is provided between the lower end of head 71 and the secondary bore of scoop 17 to prevent foreign material from collecting about the latch ring 15 and rendering it inoperable.

The stinger device 13 is lowered into the well on the secondary string 20 and is landed and latched in the secondary bore of the landing scoop 17, by guiding the seal tube thereinto. When the split latch ring 15 contacts the tapered entry surface in the upper end of the landing scoop, such ring will be elastically retracted inwardly to move into the secondary bore of such landing scoop, and when such ring reaches the annular recess 14, it will expand thereinto, and at the same time the shoulders '74 and 74a corne into Contact to permit the downwardly exerted force on the tubing string 20 to be exerted downwardly onto the body of the packer in the manner hereinafter described.

Preferably a window 79 is provided in the wall of the latch housing adjacent to the spring latch ring 47 to allow the escape of debris which might collect therein to such an extent as to prevent the latch ring from operating.

As hereinbefore mentioned, the adjustment sleeve 33 is provided for positioning the body of the packer with relation to the primary mandrel 7, and in such position is positioned against a shoulder 82 provided on the mandrel section 42. The adjustment sleeve is held in adjusted relationship to the slip mounting housing by means of suitable set screws 33a, the inner ends of which extend into an annular recess 83 provided about the adjustment sleeve 33.

The operation and function of the device hereinbefore described is as follows:

If desired the lower packer 8, which is usually of the drillable type, may be run and set in the casing before running the dua1 packer. The lower packer 8 may be a packer of the type which is run on a wire line and is pressure set by an explosive charge or fluid pressure therein, or it may be of the drillable type which may be run on a tubing string.

Also, the lower packer 8 may beof the hook wall type which is run on a tubing string and set by compression. In the latter event the packer may be made up with tubing string 7 as it is lowered and the upper packer may be spaced therefrom a suitable distance, so that the lower packer is set between the zones of production and the dual upper packer is set above the upper zone of production.

The dual packer is assembled in the manner hereinbefore described, and attached to the primary tubing string 21 and lowered into the casing in the condition shown in FIG. I.

As hereinbefore stated, the primary tubing string extending below the dual packer is customarily latched into the lower packer by forcing the latch member on the stinger into the lower packer and the primary string may be rotated to unthread the stinger therefrom, if desired. The primary string is freely rotatable through the dual packer, permitting rotation of the primary tubing string below the packer for disengagement from the primary packer. In the event a conventional hook Wall packer is employed, it is attached to the lower tubing string and may be unlatched by rotating the primary string through the dual packer, and set by lowering the weight of the primary string thereupon.

After the lower packer is set and the tubing string extending below the dual packer is engaged with the lower packer, the secondary string 20 with the stinger 13 attached thereto, is lowered into the well and the stinger 13 is guided into the secondary passage in the scoop 17 by guide surface 18, and latched therein by the spring latch 15. r

Downward force is then exerted upon the secondary string 20 which is transmitted to the packer body 2. Such downward force is transmitted through the anchor body 22 to the latch spring 47. The tapered surface 48 on the lower end of the latch spring 47 engages the tapered surface 45 on the expander ring 44, which is attached to the primary mandrel. The latch spring 47 is expanded outwardly into the annular recess 46, allowing the packer body 2 -to move downwardly over the primary mandrel 7. This causes the downward movement of the expander head 29 with the secondary mandrel 76, expanding the slips 31 outwardly into anchoring engagement with the casing wall. After the slips 31 are anchored, further downward movement of the packer body 2 will expand the packer sleeve 3 outwardly into sealing engagement with the casing wall, between the supporting heads 27 and 28. It will be noted that the pickup head 77, attached to the secondary mandrel 76, con- L tinues to move `downwardly as the packer is expanded,

10 and separates from the -shoulder 78 inside the expander head 29.

With the dual packer in set position, as shown in FIG. II, and FIGS. XII-XIIB, the slips 31 anchor the packer against downward pressure and the hydraulic piston slips 23 anchor the packer against a greater differential in pressure from below the packer.

When it is desired to remove the dual packer from the well or to another elevation in the well, the secondary string 20 is picked up, thus moving the packer body upwardly along the primary mandrel 7 until the latch spring 47 clears the coupling 43 and expander ring 44, and is thereby allowed to retract into engagement with the upper end of the expander ring 44 and thus again suspend the packer body 2 on the primary string. The upward movement of the body 2 and the secondary mandrel 76 causes the packer sleeve 3 to relax and pickup head 77 to engage the shoulder 78 in the expander head 29, causing the expander head 29 to move upwardly with relation to the slips 31, to retract the slips inwardly out of anchoring engagement With the casing.

The secondary string 20 may then be detached from the packer and removed from the well by exerting suflicient pull upwardly thereupon to retract the latch ring 15 on the stinger 13 out of engagement with landing scoop 17. The relaxed packer may then be pulled out of the well on the primary string, after rotating the tubing string section extending therebelow out of engagement with the lower packer 8.

In the event that the dual packer does not retract by pull upon the secondary string 20, the secondary string may be detached from the packer body by suicient pull thereon to unlatch the stinger 13 from the packer body. Suicient upward force is then exerted upon the primary string 21, to break the shear screws 30a.

The breaking of the shear screws 30a permits the primary mandrel 7 to be moved upwardly with reference to the body 2 until the expander ring 44 engages the shoulder 51, which moves the anchor body 22 upward. 'Ille secondary mandrel 76, threaded to the anchor body 22, moves up through the expander head 29 until there is full length for the packing sleeves 3 to relax, then causes the pickup head 77 to engage the shoulder 78 in the expander head 29, moving the expander head 29 upward with relation to the slips 31 -to `retract the slips inwardly out of anchoring engagement with the casing.

It will be noted that upon such emergency retrieval the coupling 43 is of suicient length to keep the latch spring 47 expanded out of engagement with the primary mandrel until the expander ring 44 has come into contact with the shoulder 51.

It will be seen that I have provided improvements in a dual packer, which permits same to be run and set without the danger of premature setting, while being run into the casing, which permits the primary string to be freely rotated therein for manipulation of the pipe therebelow, to attach or detach the primary string from or to a primary packer or other tool set therebelow, which is simple and easy to assemble and install, and has emergency release apparatus provided therein which permits positive retrieval of the packer in the event normal retrieval procedure is prevented, and provides other advantages hereinbefore described.

It will be understood that other and further embodiments of the invention may be made without departing from the spirit and scope of the appended claims.

I claim:

1. In a well packer, including a body having sections with parallel longitudinal passages therethrough, a resilient sleeve having parallel longitudinal passages therethrough coinciding with the passages through the body sections, the said sleeve being disposed between two of said body sections; a rst tubular member extending through one ofthe passages through the body sections and the sleeve; the sections of the body above the resilient sleeve, and the yone immediately below same, being movvabout the first tubular member for disengageably and reengageably attaching the body to the first tubular member; means on the first tubular member engageable with the latch means for expanding same out of engagement with the first tubular member to permit the movement of the body sections downwardly with relation to the first tubular member; a second tubular member extending through the other passage in the sleeve and through the body sections below the sleeve, and being attached to the body section above the sleeve in communication with the other passage through said body section; shoulder means on the second tubular member; shoulder means in the body section bellow the resilient sleeve engageable with the shoulder means on the second tubular member to suspend said body section thereto; a slip supporting housing having parallel longitudinal passages therethrough arranged to receive the first and second tubular members; frangible means connecting the housing to the first tubular member; slips slidably attached to the housing and having inner faces thereon slidably connected to the body section below the resilient packer sleeve, outwardly diverging tapered surfaces on said body section to cause the slips to move outwardly upon relative longitudinal movement therebetween; the said body section below the resilient sleeve being spaced .from the housing, to permit relative movement on the tubular members therebetween; and means to exert downward force upon the housing, to retract the latch means, to thereby permit downward movement of the housing sections with relation to the first tubular member t-o expand the slips outwa-rdly and expand the resilient sleeve.

2. The combination called for in claim 1 with the addition of an annular shoulder in the body above the packer sleeve; a shoulder on the first tubular member engageable with the shoulder in the body to suspend the body on the first tubular member for retrieval from the well upon emergency shearing of the frangi-ble means connecting the housing to the first tubular member.

3. The combination called for in claim 2 wherein the first 'tubular member is made up of two sections; a coupling connecting the sections, the said coupling being larger in diameter than the sections of the tubular member, said coupling being arranged to engage the latch member to hold same outwardly out of engagement with the first tubular member until the shoulder on the first tubular member contacts the shoulder inside the body upon emergency release of the first tubular member from the housing.

4. The combination called for in claim 1 wherein the first tubular member is rotable in the passage through the body sections and the housing.

5. The combination called for in claim 1 with the addition of hydraulically actuated piston teeth slidably mounted in the wall of one of the body sections above the resilient sleeve; and means providing communication between the said other passage and the rear of said pistons, whereby pressure entering said other passage from below the packer is transmitted to the rear of said piston teeth to force same outwardly to thereby provide an auxiliary anchor against the wall of the casing for anchoring the packer against pressure from below.

6. The combination called for in claim 1 wherein the means for exerting downward pressure on the body includes a member attachable to a secondary s-tring of pipe, having disengageable latch means thereon engageable in the said other passage through the body, whereby the secondary string may be run into the hole and latched into the said other passage after the packer is run, and may be disengaged therefrom for removal of the packer on another string of tubing attached to the body.

7. In a packer assembly, a body having dual parallel passages therethrough; a first tubular member extending through one of the passages; expansible and retractable spring latch means disengageably attaching the body to the first tubular member; means on the first tubular member, engageable with the latch means to move same outwardly out of engagement with the first tubular member upon relative longitudinal movement between the body and the first tubular member; a second tubular member attached to the body in communication with the other passage; a resilient sleeve positioned below the body having passages therethrough arranged to coincide with the passages through the body and having the tubular members extended therethrough; an expander head positioned below the sleeve, and having passages there-through slidable over the tubular members extending through the passages through the sleeve; coinciding shoulder means on the second tubular member and the passage through the expander head, for suspending the expander head to the second tubular member, said expander head being movable downwardly on the firs-t tubular member, and being in spaced relationship to the slip supporting housing; a slip supporting housing frangibly connected to the first tubular member, and having passages therethrough receiving the first and second tubular members; slips slidably attached to the housing; outwardly diverging tapered surfaces on the expander head, the said slips being slidably connected to such tapered surfaces; means engageable with the body to exert downward force thereupon to expand the latch means out of engagement with the rst tubular member to permit the body and expander head to move downwardly with relation to the first tubular member, expand the slips into engagement with a well casing, and to expand the resilient packer sleeve between the body and the expander head.

8. The combination called for in claim 7 wherein the expansible latch means is located above the packer sleeve.

9. The combination called for in claim 7 with the addition of a shoulder in the housing and a shoulder on the first tubular member arranged to contact to suspend the housing on the said tubular member upon emergency shearing of the frangible means between the slip supporting housing and the said tubular member.

10. The combination called for in claim 9 wherein there is an area of enlarged diameter about the first tubular member engageable with the spring latch means to hold same in expanded position until the shoulders contact.

11. In a packer assembly a body having first and second parallel passages therethrough; a first mandrel slidably disposed in the first passage; a second mandrel attached in the second passage; expansible and contractable latch means disengageably attaching the first mandrel to the body; means on the first mandrel engageable with the latch means for expanding same out of engagement with the mandrel to allow relative longitudinal movement between the body and the mandrel; a resilient packer sleeve positioned below the body having passages therethrough slidably receiving the mandrels, support means above and below the sleeve having passages therethrough slidably receiving the mandrels; expansible anchoring means frangibly secured to the first mandrel below the sleeve; expander means disposed between the anchoring means and the lower sleeve support, and having passages therethrough slidably receiving the mandrels; coinciding outwardly directed slidably related tapered surfaces between the expander head and the expansible anchoring means; shoulder means between the second mandrel and the expander means for suspending the expander means to the second mandrel; and means to apply downward force on the upper end of the body to expand the latch means out of engagement with the first mandrel to cause downward movement of the body, packer sleeve and expander means with reference to the first mandrel to expand the anchoring means and expand the packer sleeve between the supports therefor.

12. The combination called for in claim 11 with the addition of a plurality of hydraulically actuated anchor teeth mounted in the wall of the body above thepacker, and means to convey pressure from below the packer sleeve through the second mandrel and the wall of the body to the rear of said piston teeth to force some outwardly.

13. The combination called for in claim 11 wherein the support members for the sleeve are attached to the body and the expander member by bayonet joint connections.

References Cited by the Examiner UNITED STATES PATENTS Watt 285-401 Cox 285-401 Davis et al. 285-137 Brown et al, 166-119 Medford 166-123 Conrad et al. 166-134 10 BENJAMIN HERSH, Primary Examiner.

CHARLES OCONNELL, Examiner.

Claims (1)

11. IN A PACKER ASSEMBLY A BODY HAVING FIRST AND SECOND PAREALLEL PASSAGE THERETHROUGH; A FIRST MANDREL SLIDABLY DISPOSED IN THE FIRST PASSAGE; A SECOND MANDREL ATTACHED IN THE SECOND PASSAGE; EXPANSIBLE AND CONTRACTABLE LATCH MEANS DISENGAGEABLY ATATCHING THE FIRST MANDREL TO THE BODY; MEANS ON THE FIRST MANDREL ENGAGEABLE WITH THE LATCH MEANS FOR EXPANDING SAME OUT OF ENGAGEMENT WITH THE MANDREL TO ALLOW RELATIVE LONGITUDINAL MOVEMENT BETWEEN THE BODY AND THE MANDREL; A RESILIENT PACKER SLEEVE POSITIONED BELOW THE BODY AHVING A PASSAGE THERETHROUGH SLIDABLY RECEIVING THE MANDRELS, SUPPORT MEANS ABOVE AND BELOW THE SLEEVE HAVING PASSAGES THERETHROUGH SLIDABLY RECEIVING THE MANDRELS; EXPANSIBLE ANCHORING MEANS FRANGIBLY SECURED TO THE FIRST MANDREL BELOW THE SLEEVE; EXPANDER MEANS DISPOSED BETWEEN THE ANCHORING MEANS AND THE LOWER SLEEVE SUPPORT, AND HAVING PASSAGES THERETHROUGH SLIDABLY RECEIVING THE MANDRELS; COINCIDING OUTWARDLY DIRECTED SLIDABLY RELATED TAPERED SURFACES BETWEEN THE EXPANDER HEAD AND THE EXPANSIBLE ANCHORING MEANS; SHOULDER MEANS BETWEEN THE SECOND MANDREL AND THE EXPANDER MEANS FOR SUSPENDING THE EXPANDER MEANS TO THE

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