US2912053A

US2912053A - Squeeze cementing tools

Info

Publication number: US2912053A
Application number: US412414A
Authority: US
Inventors: Christian W Breukelman
Original assignee: Individual
Current assignee: Individual
Priority date: 1954-02-25
Filing date: 1954-02-25
Publication date: 1959-11-10
Anticipated expiration: 1976-11-10

Description

N0 10, 1959v C. w, BREUKELMAN 2,912,053

sQuEEzE CEMENTING Toons 2 Sheets-Sheet. 1-

FLW

Filed Feb. 25, 1954.

Nov. l0, 1959 c. w. BREUKELMAN sQuEEzE CEMENTING TooLs 2 Sheets-Sheet 2 Filed Feb. 25, 1954 BY E United States Patent O M 2,912,053 SQUEEZE CElVIENTlNG TOOLS Christian W. Breukelman, White Plains, N.Y.

Application February 25, 1954, Serial No. 412,414

9 Claims. (Cl. 166-146) The invention herein disclosed relates to tools for performing squeeze cementing, acidizing, washing and possibly other recompletion operations in oil wells previously lled or partially filled ywith drilling fluid or other suitable liquid.

Particularly the invention has reference to squeeze cementing tools of straddle type for forcing cement slurry into selected formation intervals and sealing the same.

Primarily the invention is designed for use in oil wells in which the casing has been cemented and afterwards gun-perforated opposite selected formation intervals to determine the nature and productive capacity of the contained uids. Intervals producing undesirable fluids such as salt water may be sealed off by the squeeze cementing tools of the present invention.

The invention may be further used to force cement slurry through casing perforations into the annulus between the casing and the surrounding wall of a well bore, to prevent vertical movementof formation uids such as oil, gas or water, behind the casing.

Other uses of the invention are to seal off bores or fractures in formations in uncased wells, when Walls of the boreholes are smooth enough, `when for instance they may have been drilled with diamond core bits. i Objects of the invention generally are to provide a straddle type squeeze cementing tool which can be used -with assurance that the tool can be recovered after completing a squeeze cementing job, and without damaging or weakening the cement placed in the casing perforations or elsewhere.

Special objects of the invention are to assure the free separation of the tool from the useful cement deposited in the well and to enable the tool, prior to being withdrawn, to be used to clean away and remove cement adherent to the wall of the casing.

Other important objects of the invention are to provide a tool of simple, rugged construction which will save time and reduce cost of operations as compared with tools for the purpose currently in use.

The foregoing and other desirable objects are attained in part in the present invention by constructing the tool so that at completion of the cementing operation the lower of two straddle packers may be unlocked and left temporarily attached to the casing while the tool is lifted to pull up a casing cleaner through the lower packer into the cementing chamber portion of the casing, where it then can be operated to remove adherent cement from the wall of the casing, and by providing the tool in the rst instance with a medium which will prevent adherence or setting of the cement on the tool, so that the tool will surely free itself of the deposited cement.

Other novel features of the invention pertain to control of circulation as between tubing carrying and forming the body of the tool, the annular casing space surrounding the tubing above and below the packers and the annular cementing chamber between the packers,

including a special bypass between the tubing above the upper packer and the cementing chamber below thisL Patented Nov. 10, 1959 packer, and which bypass as occasion may require, may be closed to the lower end of the tubing or may have an upwardly opening check Valve or velocity valve.

Other novel features of the invention and desirable objects accomplished are set forth and will further ape pear in the course of the following specification.

The drawings accompanying and forming part of the specification illustrate certain present practical embodiments of the invention. Structure, however, may be modied and changed as regards these illustrations, all within the true intent and scope of the invention as hereinafter defined and claimed.

Fig. l in the drawings is a broken sectional view of a circulating form of the tool, lowered in a well, in position for testing or cementing;

Fig. 2 is a larger broken and fragmentary sectional view of another, non-circulating form of the tool, in the position for testing and cementing; i

Figs. 3, 4 and 5 are broken sectional views illustrating successively the steps of cementing, the disintegrating and scouring of excess cement from the casing Wall and the collection of the reduced cement and slurry mixed with drilling iiuid for removal with the tool;

Fig. 6 is a broken sectional view of another form of the non-circulating type tool in the cementing position.

Fig. 7 is an enlarged horizontal sectional view of the holder for the lower packer as on substantially the plane of line 7-7 of Fig. 2.

The body of the tool is shown as made up of a length of tubing 10 which may be the same as or similar to conventional tlow tubing and therefore adapted to be connected in place by the usual couplings.

This tubular body member carries upper and lower packers 11 and 12, spaced to `straddle the perforations 13 in the well casing 14.

These packers may be mounted in relatively rotatable relation on the tubular body member, on ball race mounts as indicated at 15, 16, so that they may remain at rest, temporarily sealed to the casing while the tubing is rotated within them.

Ihe upper packer is shown as iiXed in longitudinal position on the tubing between upper and lower abutment shoulders 17, 18. 'j

The lower packer, While normally or initially locked to the tubing in Vposition establishing the perforation straddling relationship of the packers may, when desired, be unlocked from the tubing and left temporarily in position attached to and supported by the casing while the tubing is lifted in respect thereto.

Accordingly, the lower packer 12 is shown supported by a sleeve 19 surrounded by a second or outer sleeve 19a carrying friction shoes 2t) yieldingly engaging the casing, said sleeve having a ball lock connection 21 with the tubing so that upon relative rotation of the tubing and sleeve 19 within the outer sleeve 19a, the balls of the lock 21 will be released, thus to unlock sleeve 19 and the lower packer from the tubing, permitting the tubing to be raised in relation thereto. Ball locks or similar devices now in use enabling uncoupling by relative rotation of parts, may be employed for this purpose.

To prevent the cement as it dehydrates and hardens from sticking to the body of the tool, that portion of the tubing within the annular cementing chamber 22 between the upper and lower packers, is shown as equipped with a grease cylinder 23 made up of a relatively thick layer of grease pocketed between outstanding annular flanges 24 of a rubber or similar flexible sleeve 25 on a metallic supporting sleeve 26, the latter positioned between abutment Flow control between the tubing, the casing annulus and the isolated cementing chamber, is accomplished by means of a slide valve in the form of a friction held sleeve 29 slidingly engaged on the tubing between upper and

lower abutment shoulders

30, 31 for controlling ports 32 above the packers, and a bypass tube 33 extending down wardly from within the tubing above the packers, out through the side of the tubing below the upper packer, at 34, into the cementing chamber 22.

Also, the tubing is shown as having ports 35 above the packer but below the upper end of the bypass tube which closes olf the tubing at that point, these ports providing continuous communication between the casing above the packers and the open space in the casing below the tool.

The bypass tube 33 providing communication between the upper tubing and cementing chamber may be closed to the lower portion of the tubing or have controlled communication therewith.

For such purposes bypass tube 33 is shown as having an extension neck or boss 36 open to the lower body tubing which may be closed ofi by a screw plug, as shown at 37, Fig. 2, or receive an upwardly opening ball check valve 38, Fig. l, and which latter actually, through provision of an upper valve seat 39, may operate as a velocity valve, with the ball closing upwardly under predetermined high velocity conditions.

Additional flow control is effected in the form of the invention shown in Figs. 2 and 5, by means of spring closed valve elements 40 governing ports 41 in the side of the tubing above the bypass and below the slide valve, these valves opening to inward pressure from the casing annulus into the tubing, and closing against pressure from the tubing to the annulus.

Removal of excess cement adhering to the casing is effected by the provision of a scratcher or scrubber on the lower portion of the tubular body member, the same being shown as made up of flexible wires, blades or arms 42 projecting radially from the reduced diameter lower portion 43 of the tubing and adapted to yield and fold sufciently for this mechanical scrubber mechanism to pass up through the lower packer when itis unlocked from the tubing, as shown in Figs. 4 and 5.

As a practical matter, this scrubber or scraper may be made up of wires or blades helically arranged about the reduced portion of the tubing and either flexible in themselves or ilexibly connected with the tubing so that they may yield and fold inwardly suiciently to pass up or down through the sleeve of the lower packer.

In the form of the invention shown in Fig. l, the tubing is extended below the scratcher 42 in a larger diameter section 44, providing at the juncture of this with the reduced section 43 an inclined annular shoulder 45 having ports 46 therein controlled by a ring valve 47 mounted to slide over the lower section of the reduced tubular portion 43.

In the form of the invention shown in Figs. 2 to 5, a downwardly faced bottom packer 48 is mounted on the lower end of the tubular body member which will operate to protect the grease collar or cylinder against washing away or too much attrition by drilling iluid during lowering of the tool in the well. This grease cylinder forms the inner wall of the mold chamber and may be as thick as considered desirable, the greater the diameter the -less the thickness of the collar of cement 49, Fig. 4, left molded against the wall of the casing.

The packers may be ldouble or single acting, as required.

Fig. 1 shows both upper and lower packers as double acting. In such a construction one cup of each oppositely acting pair may be designed with a certain amount of clearance in one direction and to close and seal against the casing only when pressure is exerted against it in the opposite, normal sealing direction of the cup.

In the form of the invention shown in Figs. 2 to 5, both upper and lower packers are of the single cup, one- CII A way design, closing to pressure within the cementing chamber but opening to ow into the chamber from above or below.

In the form of the invention shown in Fig. 6, a oneway packer is provided at the top and a double, two-way packer is provided at the bottom of the cementing chamber.

To facilitate the scrubbing and cleaning out action prior to removal of the tool, the tubing is equipped with spring catches such as indicated at 50, near the lower end, which will pass up through the lower, released packer 12, Fig. 4, when the tubing is raised and then, snapping over this packer, will lower the same to the bottom of the tubing stroke, as shown in Fig. 5. This lengthening of the chamber enclosed between the upper and lower packers, is accompanied by the simultaneous filling of this lengthened chamber with drilling uid with which cement scoured ofI by the scraper wires is mixed into a suspension for subsequent easy removal from the wall.

In Fig. 2 packer 48 is shown releasably attached to the lower end of the tubing by shear pins 51. This is a safety device permitting the tubing to be withdrawn from the well if for any reasonrthe collar of cement 49, Fig. 4, cannot be removed after releasing lower packer 12, as previously described.

In such an event lower packer 12 will be caught under cement collar 49 and an upward pull on the tubing will shear pin or pins 51 leaving

packers

12 and 48 in the well, to be recovered at some later time if desired.

Operation Operation will be clear from the foregoing considered in connection with Figs. 3, 4 and 5, the rst of these views showing the slide valve closed and cementing accomplished through introduction of slurry down through the tubing and bypass into the annular cementing chamber defined by the packers, tubing and surrounding casing. Excess slurry left in the tubing after this operation may be circulated out of the tubing by pumping iluid into the casing through ports 41 and back up the tubing. After dehydration and setting of the cement slurry to the desired extent, the tubing may be rotated to release the ball lock and leave the lower packer frictionally attached to and supported by the casing. When this is done the tubing may be lifted as shown in Fig. 4, to carry the scraper on the lower end and normally below the packer, up through the packer past the cementing zone.

As this occurs, the catches 50 will snap over the top of the temporarily supported lower packer as in Fig. 4. Then with the next down stroke of the body of the tool, the scraper will be carried down to a lower position in the casing in the increased or lengthened clean-out chamber filled with drilling uid, aiding in the breaking up and disintegration of partially hardened cement adhereing to the casing.

When the scraper or cleaner is pulled up through the lower packer the latter becomes centered over the lower, normal or full size diameter portion 44 of the tubing, Figs. 4 and 5, and hence is held by the catches 50 in rmly centered relation.

The tool may be rotated upward and downward as much as need be to cut, scrape and clean away any cement caked or adherent to the wall of the casingand when this has been accomplished the tool may be withdrawn, lifting with it cut and broken cement particles more or less in suspension in the drilling fluid, as shown in Fig. 5. This may be regarded as a non-circulating form of the tool because the cement suspension may be lifted out of the well with the tool instead of being washed out by the circulation of fluid.

The tool shown in Fig. 6 may be operated and used substantially in the same way.

The slide valve, controlled by vertical movements of the tool, the inwardly opening check valves 40 in the tubing above the bypass, the open ports-35 in the tubing below the bypass, the bypass itself, with the possibility of closing it off at the bottom as at 37, Fig. 2, or providing it with check valve 38, Fig. l, or velocity valve at 39, the ring valve 47 on the lower end of the tubing, f.

the ball lock connection 21 enabling release of the lower packer by rotational movement of the tubing and the catches 50 for holding this packer in the lowered position, provide elements of control useful in different ways or in different relations to accomplish results desired in the way of displacing unwanted uids such as drilling mud, introducing the slurry and nally cleaning out and removing cementitious suspension.

Such operations are accomplished without disturbing or breaking away the useful deposited cement or injuring casing.

The grease layer on the tubing prevents the tool from sticking and enables separation and removal of the tool without need for jarring, hammering, drilling or the like.

In circulating forms of the tool such as illustrated in Fig. l, excess slurry remaining in the tubing after squeeze cementing may be displaced upward to a point well above the slide valve by pumping iluid slowly into the casing with the slide valve closed to force such uid through ports 35 into the tubing below the by-pass and then up through velocity valve 38.

Thereafter, after releasing the lower packer as previously described, and raising the tubing to lock this packer at the lower end of the tool, the excess slurry remaining in the tubing may be washed out at a high rate by pumping Huid down the casing through ports 32 and back up inside the tubing. Since the slurry in the tubing was raised well above the slide valve prior to this operation, there is reduced possibility that it will back-How through ports 32 and around the tubing when the tubing is raised and the slide valve is opened during this operation.

After reciprocating and rotational movements of the tubing to scour oi hardening cement adhering to the casing and mix it into a suspension in the drilling lluid between the packers, the tubing is lowered sutiiciently to close the slide valve and the cement suspension is washed out of the well by pumping uid into the casing, through ports 35 into the tubing below the by-pass through ports 45, upwards between the packers, through the by-pass and up through the tubing.

The bypass provides direct communication between the upper portion of the tubing leading to the surface and the annular space coniined between the upper and lower packers, and the ports 35 in the tubing below the bypass afford continuous communication between the casing annulus above the packers and the well space below the packers. The slide valve affords controlled communication between the casing annulus and the tubing above the bypass.

A valve to prevent pipe scale and the like accumulating in the space between the lower packer and upper end of the sleeve carrying the friction shoes is shown in the form of an annular sleeve 51, cooperable with an annular valve seat 52, over ports 53 in the wall of the tubing.

This valve will open when the tool is being lowered in the well to flush out scale and other debris from the annular space between lower packer and friction holder, up through the tubing and out the ports 35, into the an nulus above the tool.

The ports 53, however, are closed when the tool is lifted or at rest, by the annular valve ring 51, which has a loose sliding lit within the tubing, resting in the lowest position on the annular valve seat 52.

What is claimed is:

1. A squeeze cementing tool comprising a tubular body member, upper and lower packers in longitudinally spaced relation on said tubular body member for defining an annular cementing chamber in a well casing, a closure separating said tubular body member into non-communicat- 6 ing upper and lower sections, a bypass extending from the upper section and opening out into said annular ce menting chamber below the upper packer for delivering cement slurry from the upper section into saidcementing chamber, releasable means for securing the lower packer in delinite position on the tubular member and means for frictionally holding the lower packer supported on surrounding well casing when released from the tubular body member.

2. Straddle type squeeze cementing tool for injecting cement slurry into a selected formation interval exposed in a well substantially lled with liquid, comprising tubing to extend into the well bore to a point adjacent said formation interval, said tubing having upper and lower non-communicating sections separated by a closure, upper and lower packers mounted in longitudinally spaced relatively rotatable relation on said tubing below said closure and engageable with the surrounding well bore wall to deline an annular cementing chamber about the tubing isolating the selected formation interval, a bypass conduit in the tubing communicating the upper tubing section with the exterior of the tubing between the packers for delivering cement slurry conducted by said upper tubing section into said annular cementing chamber, said lower tubing section having an opening in the wall of the same below said closure and above said upper packer and a second opening in the lower end thereof below the lower packer and thereby communicating the well bore outside said tubing above the upper packer with the well bore below the lower packer, releasable means on said tubing for initially maintaining said lower packer in one position on said tubing against longitudinal movement and operable by manipulation of the tubing for releasing the lower packer from said one longitudinal position on the tubing and thereby to leave it attached to the well bore wall independently of the tubing and whereby the tubing may be reciprocated in respect to said lower packer held stationary to the bore wall, said tubing having a reduced lower portion normally below the lower packer and wall cleaning means projecting from said reduced lower portion of the tubing and foldable to pass up through the lower packer when the latter is supported as described in stationary relation on the bore wall.

3. The invention according to claim 2 with a check valve at the lower end of said bypass providing one-way communication between said bypass and said lower section of the tubing.

4. The invention according to claim 2 with a combination check and velocity valve at the lower end'lfffsaid bypass controlling communication between said upper and lower sections of the tubing.

5. The invention according to claim 2 with an extension of said tubing of larger diameter below said reduced portion for supporting said lower packer and sleeve after said reduced portion has been raised therethrough and said larger diameter extension having means for locking said lower packer and sleeve thereon.

6. The invention according to claim 2 with a catch on the lower end portion of the tubing positioned to engage over the lower packer when the tubing is raised in respect to said packer and whereby in a succeeding lowering movement of the tubing said packer will be lowered in the well bore by said tubing.

7. The invention according to claim Z with a layer of grease-like material on the tubing within said cementing chamber.

8. The invention according to claim 7 with means for preventing entering slurry from scouring oi said greaselike material including a plurality of flexible partitions extending radially from the tubing and between which said grease-like material is pocketed.

9. The invention according to claim 2, with a sleeve on that portion of the tubing within said cementing chamber below the opening of the bypass there into and hav 2,136,015 Nicks Nov. 8, 1938 8 Shuts Dec. 24, 1940 Verbe/u1 et al. Feb. 15, 1944 Gibson ..Y Nov. 7, 1944 Breukehnan 1 -.3- Aug. 26, 1947