US2585706A - Acidizing packer - Google Patents

Description

' Feb. 12, 1952 c. WARE ACIDIZING PACKER 2 SHEETS-S ""ET 1 Filed Sept. 26, 1949 N VEN TOR. CeaL Ware ATTORNEY I W M0 0 2 $5 ZMZ C. WARE ACIDIZING PACKER Feb. 12, 1952 2 SHEETSSHEET 2 Filed Sept. 26, 1949 INVENTOR. Cami Ware BY v ATTORNEY 3 mw w "am as z I P 8 Q 5 I 0 W 3 W Z 4 n w "if .0 7 0 201.4 7

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Patented F eb. 12, 1952 UNITED STATES'PATENT orgies ACIDIZIN G PACKER Cecil Ware, Houston, Tex.

Application September 26, 1949, Serial No. 117,797

7 Claims. (Cl. 166-12) This invention relates to an acidizing packer primarily designed for use in acidizing wells and for thereafter washing the wells.

It is another object of the invention to provide a packer of the character described which may be securely anchored to a well casing with swab cups both above and beneath the anchoring means and which will withstand the pressure above or beneath the packer.

It is a further object of the invention to provide a packer with anchoring slips for anchoring the packer to the well casing with novel means for expanding the slips into engagement with the well casing.

Other objects and advantages will be apparent' from the following specification, which is illustrated by the accompanying drawings, wherein:

Figure 1 is an elevational view, partly in section, of the upper end of the packer being lowered into the well casing.

Figure 2 is a side elevation, partly in section, of the lower end thereof showing also the slips.

Figure 3 is an enlarged fragmentary vertical sectional view.

Figure 4 is a side view, partly in section, of the upper end of the packer set in a well casing.

Figure 5 is a side elevation partly in section of the lower end thereof shown set in a well casing, and;

Figure 6 is an elevational view of the packer.

Referringnow more particularly to the drawings, wherein like numerals of reference designate the same parts in each of the figures, the numeral I designates an upper coupling into the lower end of which the upper end of the upper mandrel 2 is threaded, and screwed into the lower end of this mandrel there is the upper end of the lower mandrel 3.

The mid-portion of the upper coupling I is inwardly thickened and internally threaded to receive the upper end of the circulating tube 4, onto whose lower end the lower coupling 5 is threaded.

The circulating tube is spaced inwardly from the upper and lower mandrels, and said mandrels are provided with the upper bypass ports 6 beneath the upper coupling I and the lower bypass ports I through the lower coupling 5.

The lower end of the circulating tube is fitted closely through the lower end of the lower coupling 5 and threaded onto said lower end of the. circulating tube there is a nut 8.

Around the upper mandrel, and slidable thereon, there is an upper ;barrel 9, and around said there are the upper and lower swab cups Iii and I I, which are preferably formed of rubber or rubberized fabric.

The lower end of the swab cup I 0 is surrounded and clamped by a cup-like retainer I2 which fits around said barrel 9 and holds said upper swab cup in place.

The upper barrel has an external, annular, downwardly facing shoulder I3 which is engaged by an inside, upwardly facing shoulder IQ of the upper swab cup and the swab qup retainer I2 rests upon the upper end of the swab cup spacer I5 which surrounds the upper barrel and whose lower end rests on an inside, annular, upwardly facing shoulder I6 of the lower swab cup Ii.

The lower end of the upper barrel 5% is screwed into the upper end of the cage adapter Il and on the upper end of which the lower swab cup! I rests. The lower end of this swab cup is retained in place by means of a cup retainer it which clamps around the lower end of the swab cup Ii and which rests on an external, annular, upwardly facing shoulder of the cage bushing Ii.

There is a slip cage I9 whose upper end is screwed onto the lower end of the cage adapter, and within the slip cage there is a bushing 25 whose inner side tapers downwardly and inwardly and terminates in an inside, annular, upwardly facing shoulder 2|.

On this tapering face, and engaging said shoulder 2| there is a sectional releasing nut 22 whose sections are held together by a flexible ring 23 around them and seated in an external annular groove around the nut sections, and by the inside upper and lower flexible rings 23a, 23a snapped into inside grooves in said sections. The inner faces of the sections of said nut are formed with spiralled teeth which match, or align, forming right hand threads, and the lower end of the upper mandrel 2 has similar external threads which engage the threads of said nut to hold said mandrel elevated, as shown in Figures 1 and 2. There is a slip expander 24 whose upper end is fitted up into the slip cage and whose external surface is of an inverted, frusto-conical shape. This is shown more clearly in Figure 2.

Around this frusto-conical .face 25 there is a plurality of slips 25, whose outer surfaces are substantially cylindrical and toothed and whose inner surfaces taper so as to fit against the external surface of the expander 2d.

The mid-portion of the expander fits snugly about the lower mandrel 3, but its upper and lower ends are spaced from said mandrel, and withupper barrel and flared upwardly relativethereto 66 in said lower end there is an inside seat 27 to receive a ring 28, which is' fitted into said seat and may be welded onto said lower mandrel. The upper ends of the slips 25 are retained by the flexible hold-down arms, as 29, whose upper ends are secured to the slip cage by the holddown keepers 3t and whose lower ends overlap the upper ends of the corresponding slips.

The slips 25 work, snugly, through suitable bearings provided in the slip cage, and there are the flexible hold-down arms 3| whose lower ends are secured to the slip cage by the hold-down keepers 32, and the upper ends of these arms rest against the? lower ends of the slips to normally hold them inwardly.

There is a lower barrel 33 around the, lower mandrel 3 and whose upper end is screwed into the lower end of the slip cage. Around the lower end of this barrel there is the lower, downwardly opening swab cup 34 having an inside, downwardly directed rib 35 which hangs on an external, annular shoulder 38 of the lower barrel and said swab cup. is retained in place by meanssoi a retainer 3'! which fits closely about the lower barrel and which clamps around the upper end of said swab cup, and fitted around the lower barrel above the retainer and resting thereon there is a sleeve-like spacer sBsurrounding which there is a swab cup 39 similar in construction and arrangement to. the swab cup 34, and spaced thereabove, and the upward end of this spacer 38 engages underneath an internal, annular rib 49 in the swab cup39.

There is a cup. retainer 4i whose upper end is fitted around and countersunk into the lower end of the slip. cagev and whichis downwardly and outwardly flared, internally, and fits around the upper end of the swab, cup 39. and clamps it in place.

It will be. seen that the upper coupling I, upper mandrel 2, lower mandrel 3 and lower coupling 5, form a tubular support, and the upper barrel 9, cage adapter ll, slip cage 9. and lower barrel 33, form a packer body surrounding'the tubular support and that. the support and packer body are adapted for longitudinal movement relative to each other when the packer body is released from the support.

In use, the equipment may be lowered into the well until the lower end of the equipment is op-.

posite the stratum to be acidized. While being so lowered, the threads of the lower end of the upper mandrel 2 will. be in engagement with the internal threads. of the sectional releasing nut 22 so that the upper mandrel 2, will be maintained in its upper position with the bypass ports 6- open and at the same time the bypass ports I are open so that, circulation may be established down throughthe circulating tube 4, and backup around said tube and betweenv it. and the upper and lower mandrels. The requiredamount of acid may be then supplied to the tube 4 and lowered to near its lower end. However, before expelling the acid, the packer assembly should be anchored in the well casing.

In order to anchor the packing apparatus, the mandrel 2, 3 is turned to the right so as to unscrew the threads at the lower end of the upper mandrel from the threads of the releasing nut 22 and thereupon the mandrels and. tube 4 may. be lowered to the position, shown in Figures 4 and 5, the lower end of the. upper-mandrel entering .the slip expanded 24 and landing on the inwardly thickened portion thereof, as shown inliigure,v 5, and this will move the slip expander Z i downwardly and expand the slips 26 outwardly. intov firm engagement with the well casing, and this will anchor the complete equipment against downward or upward movement and at the same time the bypass ports 6 will be closed by the upper end of the upper barrel 9 so as to prevent circulation.

A pressure fluid may then be introduced into the upper end of the tube 4 which will force the acid in the tube out into the well, and since this fluid is confined beneath the packer it will be forced outinto the formation.

The equipment is lowered into the well, and anchored therein, and fluid is forced downwardly into the well through a string of tubing whose lower end is connected to the coupling I and which extends to the ground surface.

or course, the packer may be used for other" operations than merely acidizing wells, and while operations are carried on beneath the packer apparatus, the lower swab cups 34, 39 will form a seal above; or while operations are being carried on above the apparatus, such as swabbing the well above, the upper swab cups iii, II will form eilicient seals beneath. 1

When it is desirable to withdraw the packer or to re-locate it, the upper and lower mandrels may be elevated, the external threads on the lower end of the upper mandrel ratcheting past the upwardly pitched teeth on the inner side of the sectional releasing nut 22; This will require a direct upward pull only on the mandrels and not the rotation thereof, andsaid sectional threads will inter-engage, onaccount of the ring 23, so that these partswill-not automatically release but can be positively released b turning the mandrels to the right, as before; also, the bypass ports 6 will be uncovered to permit circulation and the key 28 will engage the lower shoulder of the slip expander and elevate said expander so as to release the slips and permit a re-location or withdrawal of the packer equipment.

What I claim is:

l. A packer for wells comprising, a tubular support, a tubular packer body surrounding the support and including a slip cage, a plurality of casing-engaging slips mountedin the cage, a slip expander between the slips and tubular support, a downwardly and inwardly tapering seat in the cage, an expansible nut on said seat having inside threads and said tubular support having external threads engageable with the threads of said nut to hold the tubular support and body against. longitudinal movement relative to each other, said threads being releasable upon rotation of the tubular support to allow said support to move downwardly relative to said body, interengaging means between the tubular support and the slip expander whereby the expander will move downwardly with the tubular support to expand the slips and engage them with the well casing, and a packing member above and beneath the slips and surrounding said tubular body, and engaging the well casing to resistmovement of the body in the casing to permit rotation of the support to release said threads and longitudinal movement of the support relative to the body when released therefrom.

2. A well packer comprising, a tubular support having bypass ports at its upper and lower ends to permit circulation of liquid therethrough a downwardly and'inwardly tapering seat in the cage, an expansible nut supported on said seat and having inside threads and said tubular support having external threads engageable with the threads of the nut to hold said support and body against longitudinal movement relative to each other, said threads being releasable upon rotation of the tubular support to allow said support to move downwardly relative to said body, inter-engaging means between the tubular support and the slip expander whereby said expander is moved downwardly by said support to expand the slips and engage them with thewell casing, annular packing, members around the tubular body and connected with said cage and adapted to contact the well casing to resist movement of the body in the casing to permit rotation of the support in the casing to release said threads and longitudinal movement of the support relative to the body when released therefrom, and means for closing the upper bypass port upon downward movement of said support relative to said body.

3. A packer for use in wells comprising, an upper and a lower mandrel connected together a tubular packer body surrounding the mandrels and including a slip cage, a plurality of casingengaging slips mounted in the cage, a slip expander between the slips and said mandrels, a downwardly and inwardly tapering seat in said cage, an expansible nut on the seat and having inside threads and one of said mandrels having external threads engageable with the threads of said nut to hold the mandrels and body-against longitudinal movement relative to each other, said threads being releasable upon rotation of the mandrels to allow the mandrels to move downwardly relative to the body, inter-engaging means between a mandrel and the slip expander whereby said expander is moved downwardly with the mandrels to expand the slips and engage them with the well casing and packing members around the body above and beneath the slips and adapted to contact the well casing and hold the body against movement in the casing during rotation of the mandrels in a direction to release said threads and movement of the mandrels downwardly in the body when released therefrom.

4. A packer for use in wells comprising, an upper and a lower mandrel connected together and having external threads a tubular packer body surrounding the mandrels,.casing-engaging slips around the upper mandrel, a slip expander between said slips and said upper mandrel, said body including a slip cage around the upper mandrel in which the slips are mounted, a downwardly and inwardly tapering seat in the cage, an expansible nut supported on the seat and having inside threads which are engageable with said external threads to hold the mandrels and body against longitudinal movement relative to each other, said threads being releasable upon rotation of the mandrels to allow said mandrels to move downwardly in the body, inter-engaging means between the upper mandrel and the slip expander whereby said expander is moved downwardly with the mandrels to expand the slips and engage them with the well casing, annular packing members above and beneath the slips and in operative connection with the slip cage and adapted to prevent the upward or downward passage of liquid between the packer and well casing and to hold the body against movement in the casing during rotation of the man- 6 drels in'a direction to=release said threads and movement of the mandrels longitudinally in the body when released therefrom.

5. A well packer comprising, a tubular support having a bypass port at its upper and at its lower'ends to permit circulation of liquid therethrough, a tubular packer body around the support, and including a slip cage, an outwardly moveable, casing-engaging slip mounted in the cage, a slip expander between the slip and the tubular support, an annular seat in the cage, an expansible nut supported on said sat and having inside threads and said tubular support having external threads engageable with the threads of the nut to hold said support and body against longitudinal movement relative to each other, said threads being releasable upon rotation of the tubular support to allow said support to move downwardly in the body, inter-engaging means between the tubular support and the slip expander, whereby said expander is moved downwardly by said support to move the slip outwardly and engage it with the well casing, annular packing members around the tubular body above and beneath said slips and connected with said cage and adapted to contact the well casing and hold the body stationary in the casing during rotation of the support in a direction to release said threads and movement of the support longitudinally in the body when released therefrom. and means for closing the upper bypass port upon downward movement of said support in the body.

6. A well packer comprising, a tubular support having a bypass port at its upper and at its lower ends to permit circulation of liquid therethrough, a tubular packer body around the support and including a slip cage, an outwardly moveable, casing-engaging slip mounted in the cage, a slip expander between the slip and the tubular support, an annular seat in the cage,

' an expansible nut supported on said seat and having inside threads and said tubular support having external threads engageable with the threads of the nut to hold said support and body against longitudinal movement relative to each other, said threads being releasable upon rotation of the tubular support to allow said support to move downwardly in the body, inter-engaging means between the tubular support and the slip expander, whereby said expander is moved downwardly by said support to move the slip outwardly and engage it with the well casing, annular packing members around the tubular body above and beneath said slips and connected with said cage and adapted to contact the well casing and hold the body against movement in the casing during rotation of the support in a direction to release said threads and longitudinal movement of the support in the body when released therefrom, means for closing the upper bypass port upon downward movement of said support in the body, and an inner axial tube coupled to the tubular support at its upper and lower'ends.

7. A packer for use in wells comprising a tubular support including upper and lower tubular mandrels connected together, said support having by-pass ports at its upper and lower ends to permit circulation of liquid therethrough, a tubular packer body around the support and including an upper barrel slideable on the upper mandrel, a lower barrel slideable on the lower mandrel and a slip cage connecting said barrels, a plurality of casing-engaging slips mounted in the cageuat slip expander-:betweenthe slips and the support, a downwardly and inwardly tapering seat in the cage, an expansible. nut. onv the seathaving inside threads and one. of said mandrelsr; having external threads engageable with thethreads ofsaid nut.v to hold the. support and body against longitudinal movement relative: to

each other, said threads being releasable upon easing, annular packing members on the mandrels above and beneath the slips and. adapted to, contact the well oasinggand hold the body against. movement. in the casing during rotation ofthesupport in, a direction to release said threads and movement of the support longitudinally the body when released therefrom, means for closing the upper by-pass port upon downward movement of the support in the body, andan. inner axial tube coupled to the'mandrels atv the upper and lower ends of the support.

CECIL WARE.

REFERENCES CITED The following references are of record in the fileof this patent:

UNITED STATES PATENTS Number Name Date- 1,52,5,368 Cameron Feb. 3, 1925 2,343,076 Otis et a1. Feb, 29, 1944

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