US2862563A

US2862563A - Well packer assembly for packing the annular space between conduits in a well

Info

Publication number: US2862563A
Application number: US440323A
Authority: US
Inventors: Jennings B Thompson
Original assignee: Guiberson Corp
Current assignee: Guiberson Corp
Priority date: 1954-06-30
Filing date: 1954-06-30
Publication date: 1958-12-02
Anticipated expiration: 1975-12-02

Description

Dec. 2, 1958 J. B. THOMPSON WELL PACKER ASSEMBLY FOR PACKING THE ANNULAR SPACE BETWEEN CONDUITS IN A WELL Filed June 30, 19 54 3 Sheets-Sheet 1 INVENTOR 5. Thompson W Maw ATTORNEYS Dec. 2, 1958 J. B. THOMPSON 2,852,563

WELL PACKER ASSEMBLY FOR PACKING THE ANNULAR SPACE BETWEEN CONDUITS IN A WELL Filed June 30, 1954 5 Sheets-Sheet INVENTOR J. 5. Thompson ifl Maw ATTORNEYS J. B. THOMPSON WELL PACKER ASSEMBLY FOR P Filed June 30,' 1954 Dec. 2, 1958 2,862,563

ACKING THE ANNULAR SPACE BETWEEN CONDUITS IN A WELL I5 Sheets-Sheet 5 INVENTOR mpson ATTORNEYS 8 a a. 37 n 5 6 7 2 5 0 0 4/ 9i 0 6 f 2 4 2 ll /2 Z? 92622335 9 5 KWMWMWWM .m mwm W H /7/ v% 7 4/4, I T v I 2/ U HU U U 1 HHHQ & 1I L, [\l| 1 7 30 23 8 77 a, a z 8 L m United States Patent WELL ANNULAR SPACE BETWEEN CQNDUITS IN A WELL Jennings B. Thompson, Dallas, Tex., assignor, by mesne assignments, to the Guiberson Corporation, Dallas, Tex., a corporation of Texas Application .l'une so, 1954, Serial No. 440,323 11 Claims. or. 166-204) This invention is concerned with a well packer and is particularly concerned with a well packer assembly for packing the annular space between conduits in a well.

The invention is particularly related to certain improvements in that type of well packer assembly illustrated and described in the co-pending application for patent of John J. Lane, entitled Annulus Packer, Serial No. 389,407, filed October 30, 1953, wherein a resilient packing sleeve is forced and expanded against up-raised levered arms as the arms are lowered and extended to span the annular space between two conduits to support the material of the sleeve against flowing over the packer shoe.

Such a packer assembly has particular application in so-called open hole testing, but it could be adapted for use in sealing the annular space between any two passages in-a well.

The advantages of such an assembly are clearly set forth in said co-pending application, to which reference is made.

It has been found, however, that in the employment of such apparatus, the lowered arms often become engaged with the wall of the well bore in retrieving the packer assembly from the well bore. In the assembly shown in the said co-pending application, the levered arms are flattened against a supporting base when the packer is PACKER ASSEMiiLY FOR PACKING THE set, and when the well pipe is lifted and the packer I sleeve is allowed to relax to normal diameter, the extended arms are resting on the base so that they are not free to bend downwardly when engaged with the wall of the well bore, thereby causing the packer assembly to be hung up with the wall of the well bore in many instances.

This invention relates to an improvement in such a packer assembly whereby means is provided to permit the extended supporting arms to fold down when they engage the wall of the well bore while pulling the packer assembly from the hole, to thereby prevent them from becoming hung up.

To accomplish this purpose a slip joint is incorporated between the supporting mandrel and the shoe to provide a travel area between the lower side of the supporting arms and the supporting base when the tool is in normal relaxed position. The slip joint extends upwardly from the supporting base when the tool is relaxed and the outside diameter thereof substantially coincides with the circumferential hinge line of the supporting arms, so that when the arms engage the wall of the hole on the way out, the arms are free to fold downward along the hinge line to a declined position in the space provided between the supporting base and the upper side of the slip joint.

This improvement has other advantages than preventing the arms from becoming hung up with the wall of the well bore. 7

It permits the normally up-raised supporting arms to be run in the hole in larger diameter so that when the arms are lowered and extended in the annulus, they-can actually engage, and be permitted to penetrate,.the wall Patented Dec. 2, 1958 of the well bore, because they are free to bend down "ice and out of the way when the tool is retrieved fromthe extended arms would dig into the wall of the well bore the arms would be bent down and out of the way as soon as the tool is pulled upwardly for retrieving it from the hole. It would be fair to assume that all of the arms would be bent downwardly in declined position by the time one stand of pipe is withdrawn from the hole, so that there would be no repeated hanging up of the arms on the way out.

Furthermore, as soon as the arms are turned downwardly to declined position, an annular space is provided between the ends of the arms and the well bore, which is substantially the same as the run-in clearance, so that.

the well fluid can easily by-pass the arms, thus eliminating any piston action upon-withdrawing the tool, thereby eliminating the danger of swabbing in the well below the packer assembly.

Other and further objects and advantages of my invention will be apparent upon reading the detailed specification hereinafter following, and by referring to the Fig. III is a partially sectionalized elevational'view of the packer assembly as it would appear after the packer sleeve has been relaxed and the assembly is being withdrawn from the well bore.

Fig. IV is a cross-sectional view taken along the line IVIV of Fig. I showing the key and keyway arrangement for preventing relative rotation between the man'- drel and the packer shoe.

Fig. V is a top perspective view of an individual basket-like unit, constitutingone form of supporting arms, with the arms thereon in inclined position.

Fig. V1 is a cross-sectional elevational view of an individual basket-like unit showing the arms thereon in inclined position.

Fig. VII is a cross-sectional elevational view of an individual basket-like unit with the arms thereon in extended horizontal position as they would appear after the arms have been lowered by compression and expansion.

the arms had been engaged with the wall of the well bore.

and bent downwardly as the packer assembly is withdrawn from the well bore.

Fig. IX is a partially sectionalized elevational view of a modified form of packer assembly as it-would appear as the assembly is being lowered'into the well bore.

Fig. X is a partially sectionalized .elevationalview of the modified. te m of e; pac et em y as t wouldthe appear after the packer sleeve has been expanded into sealing engagement with the wall of the well bore.

Fig. XI is a fragmentary partially sectionalized elevational view'of the modified form of the packer assembly as it would appear while the assembly is being withdrawn from the well bore.

'Fig. XII is a cross-sectional view taken along the line XII-XII of Fig. IX.

Numeral references are employed to designate the indicates an open uncased portion of a hole which has been drilled into the earth formations 11, the bottom of the hole being indicated at 12.

. The packer assembly is shown just as the tail pipe 62 has touched the bottom of the hole and immediately prior to the setting of the packer by releasing the weight of the drill pipe 15 thereupon.

An annular space 13 is provided between the wall of the well bore and the packer assembly and supporting pipe 15. It is the primary purpose of a tool of this kind to expand the sealing material of the packer sleeve into engagement with the wall of the well bore to close and seal off the annular space 13 to thereby isolate the zone in the annular space above the packer sleeve from the zone in the annular space below the packer sleeve, so that an open hole test may be made to determine the contents, pressure, flow rate and other information regarding a productive zone in the well below the packer.

, A hollow drill stem or other well pipe 15, which is usually made up of a plurality of joints, extends from the surface of the earth into the bore of the well and is attached to, and supports,.the packer assembly extending therebelow.

A valve connector sub 16 is threadedly engaged to the lower end of 'the well pipe 15 by means of companion threads 14. The connector sub 16 also affords a housing for the frangible disc 17, whichdisc is provided for the purpose of closing the bore of the well pipe and the bore extending through the packer assembly while the packer assembly is being lowered in the well bore. This prevents well fluids from passing upwardly through the packer assembly and into the drill stem while the tool is being lowered in the well bore so that there will be no intermingling of fluid from the productive formation with well fluid after the packer has been set and communication has been established between the zone below the packer and the interior of the well pipe.

After the packer sleeve has been expanded into sealing engagement with the wall of the well bore, a sinker bar, which consists of a heavy pointed bar of metal, may be dropped into the well pipe 15 and allowed to fall therethrough to strike and rupture the disc 17 so that communication is established between the bore of the drill stem and the zone below the packer sleeve, whereby fluid may flow from such zone into the drill stem where it may be entrapped by a suitable valve, (not shown) so that the fluid may be tested to determine the contents thereof after the well pipe and packing assembly have been withdrawn from the well bore.

The remnant of the frangible disc 17, after it has been so ruptured, is indicated at 18.

A downwardly facing ledge 19 is provided on the inner side of the sub 16 between which ledge and the upwardly facing projection 21 on the travel coupling 28, the outer edge of the disc-17 may be clamped and secured in place.

The travel coupling is threadedly connected between the'sub 16 and the packer hanger head 24. An internal projection Zl-is provided'at-the upper end of the 4 travel coupling 20, such projection being threadedly engaged with the sub 16 by means of companion threads 22.

A downwardly facing annular travel stop shoulder 23 is provided within the travel coupling 20, which shoulder is engageable with the upper end of the mandrel 39 to limit the telescoping movement between the mandrel and the travel coupling 20. Ordinarily, when the packer sleeve 32 is set the mandrel 39 does not engage shoulder 23, but the limit shoulder 23 is provided as van emergency stop to prevent over-expansion of sleeve 32, and damage to the tool.

The packer hanger head 24 is threadedly engaged with the travel coupling 20 by means of companion threads 25. The upper end of the hanger head 24 extends inwardly of the travel coupling 20 to provide an upwardly facing shelf '26 on which shelf the mandrel 39, and the parts carried thereby, are suspended when the packer assembly is in normal relaxed position, as shown in Figs.

I and HI.

An external annular groove 27v is formed near the lower;

which are detachably joined and held together by means of bolts 31 passing therethrough. The internal annular band 29 provided at the upper end of the split clamp 28 interfits in the external groove 27 in the hanger head 24 when the complementary halves of the clamp 28 are joined together.

An internal annular channel 30 is provided near the lower end of the split clamp 28. Such annular channel 30 interfits with the external annular lip 36 provided at the upper end of the packer sleeve bushing 35. Thereby the split clamp 28 removably attaches the packer sleeve 32 with the hanger head 24.

The packer sleeve 32 is made of resilient elastic material such as rubber or neoprene and is slidably disposed 7 about the mandrel 39. The packer sleeve 32 has an ex ternal annular bevel on the outer edge of the lower end thereof and the lower face of the packer sleeve is flat, as indicated at 34.

A metallic bushing 35 is molded in the upper end of the packer sleeve 32, said bushing having an external overhanging rim 36 at the upper end thereof which extends above the body of the packer sleeve, and the resilient materialof the packer sleeve 32 extends upwardly between the bushing 35 and the mandrel, as indicated at 3251.

The overhanging rim 36 interfits in the groove 30 in the split clamp 28.

A deformed annular projection 37 is provided on the bushing 35, such projection being molded in the resilient material of the packing sleeve 32. Suitable deformations such as ribs, grooves or perforations 38 are provided in the projection 37 in order to form a tight bond between the projection 37 and the resilient material of the packer sleeve.

A tubular mandrel 39 slidably extends through the packer sleeve 32, split coupling 28 and hanger head 24 and supports the shoe assembly 49 which is slidably and telescopically suspended thereto. The mandrel 39 has an enlarged head 41 at the upper end thereof which head provides a downwardly facing external shoulder 42. The

' shoulder 42 is engageable with the shelf 26 at the upper end of the hanger head 24'to thereby suspend the mandrel and the parts carried thereby to the hanger head 24 when the packer assembly is in normal relaxed condition in the well bore.

A shear pin 43 extends through the wall of the travel coupling 20 and into the head 41 to thereby frangibly connect the mandrel 39 with the travel coupling 20 in order to prevent the mandrel 39 from telescoping with relation to the hanger head 24 while the packer assembly is being lowered into the well bore.

A- travelhead 44 is attached ,to the' lower .end of the inandrel 39 by means of companion threads 45. An enlarged annular keyhead 46 is formed on the lower end of the travel head 44, and a key 47 is attached to the outer side of the keyhead 46. An external upwardly facing annular shoulder 48 is formed at the upper side of the keyhead 46 on which shoulder the shoe assembly 49 is suspended while the packer assembly is in relaxed condition.

The collapsible shoe assembly, against which the inclined arms of the supporting basket-like members are lowered to form a supporting base therefor, is indicated generally at 49. An adjustable and removable cap 50 forms a part of the shoe member 49. The cap 50 has a downwardly extend-ing skirt 51 thereon which is threadedly engaged with the hollow thimble 53 by means of companion threads 54. The cap 50 may be made of varying diameters to accommodate and support extended arms of varying diameters. The lower end of skirt 51 forms a downwardly facing annular shoulder 52 which is engageable with the shoulder 48 on the keyhead 46 in order to slidably suspend the shoe assembly 49 to the mandrel 39.

The hollow travel thimble 53 is arranged in telescopic relationship to the travel head 44. The travel head 44 and thimble 53 provide a telescoping slip joint between the mandrel 39 and the shoe assembly 49. The base 55', through which extends a concentric passage 56, extends inwardly to form a shelf 55a which is engageable with the lower end of the mandrel 39 and the travel head 44 to limit the telescopic movement between the mandrel 39 and the shoe assembly 49.

A vertical keyway 57 is provided in the inner side of thimble 53, in which keyway the key 47 is slidably engaged. Key 47 and keyway 57 prevent the rotation of the shoe assembly 49- with relation to the mandrel 39.

It is desirable to prevent relative rotation between shoe assembly 49 and mandrel 39 so that the well pipe can be rotated for operating tools which may be above the packer assembly. Such tools form no part of this invention and are not shown in the drawings.

When the packer assembly is in normal relaxed position, with shoe assembly 49 slidably suspended to the mandrel 39, as shown in Figs. 1 and III, a vertical travel space 58 is provided in the thimble 53 and the upper end of the travel head 44 extends above the cap 50 and the upper face 78 thereof is engaged with the lower side of the nest of basket-like plates 68, thus providing a travel area 59 between the lower side of the nest of plates 68 and the cap 50. The

travel areas

58 and 59 are preferably equal in length so that when the shoe assembly is telescoped to maximum extent allowed, the upper faces of cap 50 and travel head 44 will substantially coincide, thus forming a straight lateral supporting shelf for the arms 72 when they are extended to horizontal position. It will be seen that the cap 50 and the thimble 53 may telescope with relation to the travel coupling 44 within the limits of the

travel spaces

58 and 59 when weight or force is applied downwardly upon the packer assembly.

A coupling 60 attaches the perforated tail pipe 62 with the base 55 of the thimble 53 by means of companion threads 61. The tail pipe 62 has perforations 64 through the wall thereof through which perforations fluid may pass and flow upwardly through the packer assembly into the well pipe. The tail pipe 62 is closed at the lower end as indicated at 63.

A nest of typical basket-like supporting plates 68 are disposed about the mandrel 39 between the upper end of the travel head 44 and the outer annular shoulder 69 on the mandrel. It will be understood that other forms of levered supporting arms may be employed to carry out my invention, the nested basket type being merely illustrative.

The basket-like plates 68 are preferably made of relatively flexible and deformable metallic material so that they may be easily deformed and bent to lower and ex 8 tend the initially inclined arms thereon into the annular space 13 when the packer sleeve 32 is forced and expanded thereagainst.

The beveled surface 33 of the packer sleeve 32 engages, and coincides with, the upper outer edge of the uppermost basket-like plate in the nest of baskets 68 so that as the packer sleeve is forced and expanded against the up-raised arms of the basket members, the arms will be lowered into the annulus as the resilient material of the packing sleeve progresisvely flows into and fills the space provided between the flat end 34 of the packer sleeve and the horizontally disposed inner ring of the basket members.

In Figs. V and VI is shown the typical construction of a single basket-like plate, indicated generally at 71, as?

such unit appears before the arms thereon are lowered by expansion of the packer sleeve 32 thereagainst.

Such basket unit 71 has a plurality of lever arms 72 extending angularly upward from a central horizontally disposed ring 74. The arms 72 are defined by radially extending slots 73. A central hole 75 extends through the ring 74, and the arms 72 extend upwardly from a hinge line 76 at the outer edge of the ring 74. The arms 72 are in effect hinged to the ring 74 along the hinge line 76, and may be' bent downward about the hinge line 76 when the central ring 74 is supported on a base such as that provided by the upper face of the travel head 44 or the upper face of travel collar 88 and the packer sleeve 32 is forced against the up-raised arms 72, or when the outer ends of the arms are held, as by engagement with the wall of the well bore, and upward force is applied to the well pipe.

Before lowering the packer assembly into a well bore the various parts thereof are assembled in the position shown in Fig. I, with the diaphragm 17 secured in place to close the passage through the packer assembly and the drill pipe. The mandrel 39 is attached by means of the shear pin 43 to the travel coupling 20. The shoe assembly 49 and the tail pipe 62, carried thereby, are suspended to the travel head 44 by engagement of the shoulder 48and the shoulder 52, the shoe assembly being slidably and telescopically related to the travel head 44. The nest of plates 68 are positioned about the mandrel 39 between the shoulder 69 and the uper face 70 of the travel coupling 44. The nest of plates 68 are thus secured against sliding vertically with relation to the mandrel 39 while the tool is being lowered into the well bore. The packer sleeve 32 is positioned about the mandrel 39 and attached to the hanger head 24 by means of the split clamp 28, said sleeve 32 being arranged in slidable relation to the mandrel 39, and the resilient material thereof is in relaxed condition while the packer assembly is being lowered into the well bore. It-will be noted that the upwardly extending arms 72 of the nest of plates 68 engage and support the lower end of the packer sleeve 32, and that the upwardly extending portion of the travel head 44 engages and supports the lower side of the nest of plates 68. The upper face 70 of the travel head 44 is substantially of the same diameter as the horizontally disposed rings 74 of the plates 72 and the outer edge of said upper face 78 substantially coincides with the hinge line 76 of the plates71.

After the packer assembly has been so assembled, as shown in Fig. I, it is attached to the well pipe 15 by means of the connector sub 16 and the well pipe is progressively made up by adding successive joints thereto as the packer assembly is lowered into the well bore.

When the lower end of the perforated tail pipe 62 engages the bottom 12 of the Well bore. 18, the weight of the well pipe 15, which is very heavy, is gradually released upon the packer assembly. The weight of the well pipe is ordinarily sufficient to break the shear pin 43, but in the event such weight is not sufli'cient, the well pipe can be raised and allowed to fall against the bottom of the well bore to break the shear pin 43 by jarring action.-

Prior to the breaking of the shear pin 43 the force of v the weight of the drill pipe applied to the packer assembly causes the shoe assembly 49 to slide upwardly about the travel head 44 until the shoulder 55a engages the lower end of the mandrel 39 and travel head 44, at which time the upper face of the cap 50 comes into horizontal alignment with the upper face 70 of the travel head 44. The length of the travel area 58 is so arranged that when the lower end of the mandrel 39 and the travel head 44 engage the shoulder 55a of the base 55 of thimble 53, the upper faces of the cap 50 and the travel head 44 are substantially in horizontal alignment, and the upper faces of these two

members

44 and 50 thus form a supporting base against which the arms 72 of the plates 71 may be lowered and extended into the annulus 13 to substantially horizontal position.

After shear pin 43'has been broken, force applied by the weight of the pipe 15, or otherwise, causes the mandrel 39 to telescope with relation to the travel coupling 20, thus collapsing the packer assembly in accordion-like fashion, thereby shortening and radially expanding the resilient material of the pack-er sleeve 32 as it slides with relation to the mandrel 39. The forceapplied to the packer sleeve 32 is applied through the packer sleeve to the outer ends of the arms 72 of the plates 71, causing the arms to bend downwardly about their hinge lines 76 and the arms extend radially outwardly into the annulus 13 as the packer sleeve is expanded. The arms are so lowered and extended until they engage, and are supported by, the upper face of the cap 50. In such position the arms are substantially in horizontal position and substantially span the annular space 13 so that they center and support the resilient material of the packer sleeve 32 and prevent such material from being flowed and extruded about the outer ends of the arms. In such horizontal position the arms 72 actually extend beyond the cap 50, and support the expanded packer sleeve 32 by cantilevered force.

As previously stated, by employment of the elongated slip joint arrangement between the mandrel 39 and the shoe assembly 49, the plates 71 can be made of such diameter that the outer ends of the arms 72 could actually engage and penetrate the wall of the well bore, when extended, thereby eliminating entirely any annular space between the ends of the arms and the wall of the well bore, thus positively preventing any flow and extrusion of resilient material about the ends of the arms. It is preferable, but not necessary, that the arms .be made of such diameter and be so set when they are lowered, not only for the purpose of positively preventing the flow of resilient material about the arms, but to assure that the arms would be bent downward to declined position when thepacker assembly is withdrawn from the well bore so as to provide an annular passage about the ends of the arms for the by-pass of well fluid in order to eliminate any possibility of swabbing in the well below the packer assembly upon withdrawal of the tool from the well.

After the packer sleeve 32 has been shortened and radially expanded until it comes into sealing engagement with the wall of the well bore, in the manner described above, the disc 17 may be ruptured by dropping a sinker bar (not shown) into the well pipe 15, thereby establishing communication between the zone below the packer and the interior of the well pipe. A sample of the fluid from a productive zone below the packer may be entrapped in the well pipe 15 by means of a suitable and conventional valve arrangement (not shown), and other tests may be made of the productive formation while the packer is set. The well pipe and packer assembly may then be withdrawn from the well bore, in order to recover the sample of fluid and test same to determine the contents thereof.

When the well pipe 15 is lifted and the weight thereof is released from the packer assembly, and the tail pipe 62 is lifted from engagement with the bottom of the well bore, the shoe assembly 49 is free to move downwardly about the travel head 44'ur1 til the shoulder 52 engages the shoulder 48, thus suspending the shoe assembly to the travel head 44. The mandrel 39 is also free to slide downwardly through the packer sleeve 32 until the shoulder 26 on' the hanger head 24 engages the shoulder 42 on the enlarged head 41, thus suspending the mandrel 39 on the hanger head 24. The resilient material of the packer sleeve 32 is thereby allowed to relax and elongate to its normal condition and the nest of plates 68, the arms 72 of which are now extended outwardly in substantially horizontal position, are supported from below solely by the upper side of the travel coupling 44, said upper side 70 being substantially in coinciding relationship to the inner ring 74 of the plates. It will be seen that the arms 72 are not now supported from below and are free to bend downwardly over the travel head 44. At such time the outer ends of the arms 72 of the nest of plates 68 could be in slight penetrating contact with the wall of the well bore so that upon application of upward force by the withdrawal of the well pipe 15, the arms 72 would be caused to bend downward to a declining position over the travel head 44 until the arms are freed of contact with the wall of the well bore.

After the arms 72 have been so bent downward about their hinge lines 76 they would be substantially in the position shown in Figs. III and VIII.

Should the ends of the arms engage the wall of the well bore during the withdrawal of the tool from the hole, they would be bent downward to free them of contact with the wall of the well bore, thus preventing them from becoming hung-up as the tool is being withdrawn.

Sufficient space, indicated at 59, is provided between the arms 72 of plates 63 and the upper face of the cap 50 to permit the arms 72 to be bent downward to the maximum extent permitted by the outside diameter of the travel head 44. By adjusting the diameter of the travel head 44 and the inner ring 74 of the plates 71, the arms 72 could be permitted tofold downwardly until they assume a substantially vertical position. The downward inclination of the arms 72, after they have been so bent downward, wouldpermit them to easily slide over any obstructions or irregularities in the well bore on the way out. In other words, in such position, they present adownwardly inclined tapered surface which could slide over such obstructions.

In Figs. IXXII is shown a modified form of the packer assembly, employing an elongated slip joint between the shoe assembly 87 and the mandrel 82 to permit the arms 72 of the nest of plates 68 to be folded downward to declining position, for the same purposes as related above in connection with the preferred form.

In such modification the well pipe 15 is connected to the coupling 20a by means of the sub 16, and the diaphragm 17 is clamped in place between the sub 16 and coupling 20a to initially close the bore through the packer assembly and the well pipe in the same manner as was described hereinabove.

However, in said modification the modified coupling 20a is threadedly engaged to the modified hanger head 24a by means of companion threads 80, and the modified mandrel 82 is threadedly engaged to the inner side of the hanger head 24a by means of companion threads 81, so that the upper end of the mandrel is fixedly secured to the coupling 20a and may not telescope with relation thereto, as in the preferred form. In the modified form the travel space for the mandrel is provided in the shoe, as will be explained.

The packer sleeve 32, in said modification, is slidably' disposed about the mandrel 82 and is suspended to the hanger head 24a by means of the split coupling 28 in the same manner as was described above in connection with the preferred form. The lower end of the packer 68 in the same manner as was described above.

sleeve 32 engages, and is supported by, the nest of plates plates A head ring 83 is threadedly engaged to the lower end of the mandrel 82 -by means of the companion threads 84. A key 85 is provided on the outer surface of the head ring 83, and the head ring 83 provides an upwardly facing shoulder 86 on which shoulder the modified shoe assembly 87 is slidably suspended.

A travel collar 88 is slidably disposed about the mandrel 82, and rests upon the upper face of head ring 83, when the packer assembly is in relaxed position as shown in Figs. IX and Xi.

When the packer assembly is in relaxed position while being run into the well bore, as shown in Fig. IX, or when it is being withdrawn from the well bore, as shown in Fig. XI, the travel collar 88 extends upwardly abovethe shoe assembly 87 and engages and supports the nest of 68. The upper face of collar 88 substantially coincides with the inner rings 74 of the plates 71 to thereby provide an area 89 between arms 72 and the upper face of the shoe assembly 87 in which the arms 72 may be lowered upon withdrawal of the packer assembly from the well bore.

The travel collar 88 includes a portion of reduced diameter 90 on the lower end thereof which forms a downwardly facing outer annular shoulder 91 thereon.

The shoe travel limit coupling 92 has an internal an nular upwardly facing shoulder 93 thereon which is engageable with the downwardly facing shoulder 91 on the travel collar 88 to limit telescoping movement between the travel limit coupling 92 and the travel collar 88. The travel space 94, between the

shoulders

91 and 93, determines the limit of the telescoping movement between the shoe assembly 87 and the travel collar 88, and the length of such travel space 94 is so arranged that when the

shoulders

91 and 93 are engaged the upper face of the shoe. assembly 87, formed by the upper faces of the travel coupling 92 and removable cap 95, substantially coincides with the upper face of the travel collar 88. Thus the upper face of the shoe assembly 87 and the upper face of travel collar 88 form a supporting base against which arms 72 may be lowered to substantially horizontal position to span the annular space The adjustable and removable cap 95, which forms a part of the upper face of the shoe assembly 87, is threadedly engaged to the travel coupling 92 by means of companion threads 96. The diameter of the cap 95 may be varied, as desired, to form a proper support for different diameters of plates 71 when the arms of such plates are lowered thereagainst.

The modified hollow travel thimble 97 is threadedly connected to the lower end of the travel limit coupling 92 by means of companion threads 98. The thimble 97 has a base 99 with a concentric passage therethrough, and the perforated tail pipe 101 is threadedly engaged in such passage by means of companion threads 102.

A vertical keyway 0 is provided on the inner side of the thimble 97, in which keyway the key 85. is slidably disposed. The key 85 and keyway 100 PIC? vent the rotation of the shoe assembly 87 with relation to the mandrel 82, for the same purposes as related in connection with the key and keyway arrangement, shown in the preferred form.

It is also desirable to prevent the rotation of the shoe assembly with relation to the mandrel (in both the preferred and modified forms of the packer assembly) so that the plates 68 will not be rotated when frictionally engaged with the upper face of the shoe assembly. It ispreferable that the slots 73, in the separate plates 71, be maintained in staggered relationship (as shown in the drawings), when they are nested, in order that there are no: gaps through which the resilient material of the packer sleeve may flow when the packer sleeve is corn-. pressed and expanded against the plates.

A shear p nf 103 extends through the wall of the hol low travel thimble 97 and the head ring 83 and frangibly connects these two members while the tool is being run into the hole. The shear pin 103 prevents sliding movement between the shoe assembly 87 and the mandrel 82 while the packer assembly is being run into the hole, so that if'the shoe assembly should engage an obstruction in the well bore while the tool is being lowered, the shoe assembly cannot move upward to a position of engagement with the nest of plates 68 to thereby cause the premature flattening of the plates and expansion of the packer sleeve 32.

For lowering the modified packer assembly into the well bore it is assembled in the manner shown in Fig. IX, with the tail pipe 101 attached thereto, and the diaphragm 17 secured in place to close the passage through the packer assembly and through the well pipe 15.

When the lower end of the tail pipe 101 contacts the bottom of the well bore, the weight of the string of drill pipe 15 is gradually released upon the packer assembly and the travel limit coupling 92 is caused to telescope with relation to the travel collar 88 until the shoulder 91 engages the shoulder 93. At such time the upper face of the shoe assembly 87 (formed by the upper faces of the travel limit coupling 92 and cap 95) is in horizontal alignment with the upper face :of the travel collar 88 and the upper face of the shoe assembly 87 is in position to engage and support the levered arms 72 of the nest of baskets 68 when such. arms are lowered to horizontal position by. forcing the resilient packer sleeve 32 thereagainst.

The downward force applied by the weight of the well pipe 15 is usually sufficient to break the shear pin 103. However, in the event the weight of the drill pipe is not suflicient to shear the pin 103, the drill pipe and packer assembly may be raised and allowed to drop against the bottom of the well bore to break the shear pin 103.

When the shear pin 103 has been broken, the mandrel 82 is free to move downward in sliding relation to the packer sleeve 32 and travel collar 88 and to telescope with relation to the travel thimble 97. As the .mandrel 82 moves downward in relation to the thimble 97, the packer sleeve 32 is forced against the upraised arms of the nest of plates 68 and is shortened and expanded against the arms 72 of the nest of baskets as the arms are lowered and extended into the annulus 13. The arms are lowered and extended until they come into contact with the upper face of the packer shoe assembly 87, at which time the ends of the arms are in close proximity to the walls of the well bore, and preferably engage and penetrate the wall of the well bore, for the purposes as explained in connection with the operation of the preferred, form hereinbefore described.

The mandrel 82 may be telescoped with relation to the I thimble 97 until the packer sleeve 32 has been expanded to sufficient extent to come into sealing engagement with the wall of the well bore. The telescoping movement between thimble 97 and mandrel 82 is limited by the length of travel space 104 between the base. 99 of the thimble and the lower end of the mandrel. Travel space 104-is preferably of such length that the mandrel does not contact the base 99 when the packer sleeve is expanded sufficiently to seal the annular space 13, but in the event excessive force is applied to the packer assembly, the mandrel can contact the base 99 and protect the tool against damage by over-contraction.

After the'packer has been so set the disc 17 may be ruptured As described above, tests may be made, a sample of the fluid in the zone below the packer may be taken, and the well pipe and packer assembly may be withdrawn from the well bore.

When the weight of. the well pipe 15 is lifted from the packer assembly and the tail pipe 101 is lifted from engagernertt with the bottom of the well bore the pressure is released from the packer sleeve 32 allowing it to relax 1 1 and elongate to normal condition. The packer shoe assembly 87 and travel collar 88 are allowed to slide downward upon mandrel 82 until the lower end of the travel collar 83 engages the shoulder 86011 the head ring 83, and the shoe assembly 87 is' allowed to further slide downward about the travel collar 88 until the lower end of the travel limit coupling 92 engages the shoulder 86, thereby suspending the shoe assembly 37 to the mandrel 82. The packer assembly is thus returned to normal relaxed condition as shown in Fig. XI. As upward force is applied to withdraw the packer assembly from the well bore, the horizontally extended arms 72, which are preferably engaged with the walls of the well bore, may be folded downwardly over the travel collar 88 to substantially the position shown in Fig. XI, to thereby prevent them from becoming hung-up with the wall of the well bore as the packer assembly is withdrawn from the well, and permitting the by-pass of well fluid between the Wall of the well bore and the outer ends of the arms as the packer assembly is withdrawn.

Although it is preferable that the arms of the basket members engage the wall of the well bore, when initially extended to horizontal position, it is emphasized that such is not necessary to the effective operation of the packer assembly, and to the advantages provided by this invention. The slip joint arrangement between the shoe and the mandrel has utility even though arms 72 do not engage the wall of the well bore when initially extended. Such arrangement would nevertheless permit the arms to fold downward out of the way at any time they became engaged with the wall of the well bore while moving upward in the well bore, and thus be prevented from hanging up. In any event, this improvement permits the optimum support for the expanded packer sleeve, and provides optimum sealing without the danger of sticking the tool in the hole. This is true of both forms of the invention shown herein.

It will be apparent that I have made improvements in a well packer of tle type described which positively prevents the extrusion of the resilient material of the packer sleeve about the supporting base, which prevents the supporting arms from becoming hung-up with the wall of the well bore when the packer assembly is withdrawn from the well, and which permits the arms of the supporting plates to be bent downward to a declining position in order to provide an annular space between the outer ends of the arms and the wall of the well bore to thereby permit the by-pass of well fluid as the tool is withdrawn from the well bore, and also permits the downwardly slanting arms to pass over obstructions in the well bore as the tool is being withdrawn.

It will also be apparent that other forms and modifications of structure may be made to carry out my invention without departing from the spirit and scope of the appended claims.

I claim:

1. In a packer assembly, a mandrel; an elastic sleeve slidably disposed on the mandrel; a supporting base slidably suspended from the mandrel; a plurality of levered arms carried about and supported by the mandrel and arranged to rest on said base, said arms being initially inclined and being adapted to support the said elastic sleeve; and means disposed at the upper end of the elastic sleeve to force said elastic sleeve against the arms to lower and extend them outwardly.

2. In a packer assembly, a mandrel; an elastic sleeve slidably disposed on the mandrel; a supporting base slidablysuspended from the'mandrel; a plurality of levered arms carried about and supported by the mandrel and arranged to rest on said base, said arms being initially inclined and being adapted to support the said elastic sleeve; means disposed at the upper end of the elastic sleeve to force said elastic sleeve against the arms to lower. and extend them outwardly; and means to prevent rela'-' 12 tive rotation between the mandrel and the supporting base.

3. A packer assembly for sealing an annular space between two conduits comprising, a mandrel adapted to be supported by the inner conduit; an elastic sleeve slidably disposed on the mandrel; a supporting base slidably carried by the mandrel; a plurality of nested basket-like members carried about the mandrel and adapted to rest on said base, said basket-like members having arms thereon extending upwardly, the arms having free ends arranged to engage the sleeve member, and said arms being adapted to move arcuately downwardly and outwardly in response to downward thrusting force applied to the elastic sleeve; and means disposed at the upper end of the sleeve to apply down-thrusting force to the sleeve.

4. In a device of the class described, a mandrel; a shoe member slidably carried on the lower end of the mandrel; a nest of basket-like members disposed about the mandrel, each basket-like member having a plurality of arms spaced thereabout and initially extending upwardly, the said arms being supported on the mandrel and arranged to be extended outwardly into engagement with the shoe member when the shoe member is telescoped in relation to the mandrel; an elastic sleeve slidably carried about the mandrel, the lower end of said sleeve being arranged to engage the upraised arms of the uppermost .basket member; and means at the upper end of the mandrel for suspending it on a well pipe; and means disposed at the upper end of the sleeve to force the sleeve against the arms to lower the arms into engagement with the shoe.

5. In a packer assembly, a mandrel; an elastic sleeve slidably arranged about the mandrel; a shoe assembly slidably suspended from the mandrel; a plurality of radially disposed arms arranged about and supported by the mandrel below the sleeve, said arms being initially inclined upwardly and being initially spaced from the shoe assembly, but being arranged to contact the shoe assembly upon telescoping movement between the mandrel and the shoe assembly; the sleeve being arranged to slide downwardly with relation to the mandrel to lower the arms against the shoe; and means disposed at the upper end of the sleeve to force the sleeve downwardly against the arms.

6. In a packer assembly, a mandrel; an elastic sleeve slidably arranged about themandrel; a shoe assembly slidably suspended from the mandrel; a plurality of radially disposed arms arranged about and supported by the mandrel below thesleeve, saidarms being initially inclined upwardly and being initially spaced from the shoe assembly, but being arranged to contact the shoe assembly upon telescoping movement between the mandrel and the shoe assembly; the sleeve being arranged to slide downwardly with relation to the mandrel to lower the arms against the shoe;. means to prevent relative rotation between the shoe assembly and the mandrel; and means disposed at the upper end of the sleeve to force the sleeve downwardly against the arms.

7. In a packer assembly, a mandrel; an elastic sleeve slidably carried about the mandrel; a shoe assembly slidably carried by the mandrel; an elongated slip joint arranged between the, mandrel and the shoe assembly to provide for sliding longitudinal. movement between the mandrel and the shoe assembly; a plurality of initially inclined arms carried about the mandrel and supported thereby in spaced relation to the shoe assembly; means to telescope the shoe assembly with relation to the mandrel; means disposed at the upper end of the sleeve to force the elastic sleeve downwardly against the arms to thereby lower the arms to substantially horizontal position against the shoe assembly and expand the elastic sleeve; and means to reverse the telescoping movement between the shoe assembly and the mandrel to provide a space in which the arms may be lowered to declining position in a well annulus.

8-. In a packer assembly; a mandrel; an elastic packer slidably carried about the mandrel; a shoe assembly slidably carried by the mandrel; a sleeve member carried by the lower end of the mandrel and being slideably related to the shoe, the said sleeve being located exteriorly of the mandrel below the packer and having an annular face at the upper end thereof, the upper end of said sleeve member being initially extended above the shoe assembly; a plurality of initially inclined arms carried about the mandrel and having a horizontal base portion resting on the sleeve member; means to telescope the shoe assembly with relation to the sleeve to bring the upper face of the shoe assembly in alignment with the upper face of the sleeve so as to provide a continuous surface to receive the lowered arms and to support them in position bridging the annular space between the mandrel and the wall of a well bore; and means disposed at the upper end of the sleeve to force the packer against the arms to lower them to a position of support on the upper face of the shoe assembly and the upper face of the sleeve; and means to reverse the movement between the sleeve and the shoe assembly to provide a space between the arms and the shoe in which the arms may be turned to a downwardly inclined position over the sleeve.

9. In a device of the class described, a tubular coupling arranged to be connected to a well pipe; a mandrel frangibly connected to said coupling and arranged for telescoping movement with relation to the coupling and suspended thereto; an elastic sleeve connected to said coupling and being slidably arranged about the mandrel; a shoe assembly slideably carried at the lower end of the mandrel; a plurality of initially inclined arms carried about and supported by the mandrel below the elastic sleeve in spaced relation to the shoe assembly; means to telescope the shoe assembly with relation to the mandrel and to telescope the mandrel with relation to the coupling to thereby force the sleeve against the arms and lower the arms against the shoe; and means to reverse the movement of the shoe and the mandrel to permit the arms to be lowered to declining position.

10. In a device of the class described, a mandrel arranged to be connected to a well pipe; an elastic sleeve arranged to be connected to a well pipe and slideably disposed about the mandrel; a shoe assembly slidably carried by the lower end of the mandrel and arranged to telescope with relation thereto; a plurality of initially in clined arms carried and supported by the mandrel and spaced from the shoe; means to telescope the shoe as sembly with relation to the mandrel to move the shoe assembly in position to support the arms when in horizontal position; means to reverse the relative movement between the shoe assembly and the mandrel to again space the arms from the shoe assembly to provide an area in a well annulus within which the arms may be lowered to declining position; and means disposed at the upper end of the sleeve to force the sleeve downwardly against the arms.

11. In a packer assembly; a mandrel; an elastic packer slidably carried about the mandrel; a shoe assembly slidably carried by the mandrel; a sleeve member carried by the lower end of the mandrel and being slideably related to the shoe the said sleeve being located exteriorly of the mandrel below the packer and having an annular face at the upper end thereof, the upper end of said sleeve member being initially extended above the shoe assembly; aplurality of initially inclined arms carried about the mandrel and having a horizontal base portion resting on the sleeve member; a shoulder on the mandrel engageable with the base portion of the arms to prevent longitudinal movement of the arms on the man- 1 drel; means to telescope the shoe assembly with relation to the sleeve to bring the upper face of the shoe assembly in alignment with the upper face of the sleeve so as to provide a continuous surface to receive the lowered arms and to support them in position bridging the annular space between the mandrel and the wall of a Well bore; and means disposed at the upper end of the sleeve to force the packer against the arms to lower them to a position of support on the upper face of the shoe assembly and the upper face of the sleeve; and means to reverse the movement between the sleeve and the shoe assembly to provide a space between the arms and the shoe in which the arms may he turned to a downwardly inclined position over the sleeve.

References Cited in the file of this patent UNITED STATES PATENTS 1,038,080 Booe et a1. Sept. 10, 1912 1,549,168 Townsend Aug. 11, 1925 2,171,049 Simmons Aug. 29, 1939 2,390,372 Johnston et a1. Dec. 4, 1945 2,734,582 Bagnell Feb. 14, 1956