US2954827A

US2954827A - Method and apparatus for placing sealant in wells

Info

Publication number: US2954827A
Application number: US656127A
Authority: US
Inventors: Basil W Wheeler
Original assignee: Mcgaffey-Taylor Corp
Current assignee: Mcgaffey-Taylor Corp
Priority date: 1957-04-30
Filing date: 1957-04-30
Publication date: 1960-10-04
Anticipated expiration: 1977-10-04

Description

Oct. 4, 1960 B. w. WHEELER METHOD AND APPARATUS FOR PLACING SEALANT IN WELLS 5 Sheets-Sheet 1 Filed April 30, 1957 INVENTOR. 52574 W M42256 JiOEZ Q (M gda firraeA/zz 1960 B. w. WHEELER 2,954,827

METHOD AND APPARATUS FOR PLACING SEALANT IN WELLS Filed April 30, 1957 I5 Sheets-Sheet 2 5 256. .5 iii 22%. 6: 12

f J9 Q E J6 INVENTOR.

A 845/; W M5545? BY j? a (aw irraen/aw METHOD AND APPARATUS FOR PLACING SEALANT IN WELLS Filed April 30, 1957 Oct. 4, .1960 B. w. WHEELER 3 Sheets-Sheet 3 I NVE NTOR 54.574 144' Middle BY (Q Q irraen/zz United States Patent fifice 2,954,827 Patented Oct. 4, 1389 METHOD AND APPARATUS FOR PLACING SEALANT IN WELLS Basil W. Wheeler, Long Beach, 'Calif., assignor to McGatfey-Taylor Corporation, Long Beach, Calif., a corporation of California Filed Apr. '30, 1957, Ser. No. 656,127

14 (Jlaims. (Cl. 166-462) This invention relates to a well tool for sealing leaks and making repairs in wells, particularly cased oil wells, by placing therein where required, a semi-solid plastic sealant having a viscosity such as will inhibit migration thereof after placement in selected zones.

It is an object of this invention to provide a highly efficient tool of this character, which is constructed and arranged to carry into a cased well, sufiicient sealant to permit of the placement of the sealant as required to seal one or more cracks, breaks or perforations in the well casing or to meet the repair needs of the particular well, with one run of the tool into the well.

It is another object, to provide a tool such as described which after being positioned in the well, readily may be raised or lowered and operated as desired to place the sealant at required dilferent levels, without necessitating withdrawal thereof from the well for reloading the tool with seal-ant after each, or in fact, a number of sealant placement operations.

It is another object to provide a well tool such as .described in which a tubing string-operated pump and a large capacity sealant storage unit are constructed .and combined in a manner making it possible to dispense desired amounts of sealant responsive to the pump being operated to force fluid into the sealant storage unit, and in accordance with the duration of operation of the pump.

Another object of this invention is to provide a tool such as described having a novel and efficient means whereby the pump may be operated to clean out residual sealant that may remain in the tool after the sealant storage unit has been emptied.

A further object hereof is the provision in the'tool of a novel floating piston assembly operable in a sealant containing barrel responsive to fluid pressure derived from the pump, to force sealant out of the barrel into a selected zone in the well.

It isanother object of this invention to provide a plastic placement tool such as described in which the pump and the sealent storage barrel are constructed and arranged so that it is impossible to expel all of the sealant from the barrel with one complete down stroke of the pump ,piston, thereby assuring that afterthe initial operation of the tool to effect a placement of sealant in a selected zone in the well, there will remain in the storage barrel sufficient sealant to effect the several additional sealantplace- .ment operations at other selected zones.

It is another object hereof to provide a tool such as described wherein the floating piston assembly is provided with a through passage sealed by closure means which when opened makes it possible for the pump to force fluid through the barrel for washing out any sealant remaining in the tool after the barrel has been emptied.

It is another object to provide a tool such as described wherein the passage through the floating piston assembly is closed by a frangible closure subject to being ruptured only when the piston assembly is at rest at the end of the stroke required to empty the sealant barrel, and continned operation of the pump develops a predetermined pressure against the closure greater than the pressure to which the closure is subjected during movement of the piston assembly.

An additional object of this invention is the provision of a tool such as described which will indicate to an operator at the top of the well when the sealant storage barrel has been emptied, due to the fact that continued operation of the pump when the floating piston bottoms in the barrel, will develop a fluid pressure increase that readily may be noted at the top of the well.

This invention possesses many other advantages and has other objects which may be made more easily apparent from a consideration of the embodiments of the invention shown in the drawings accompanying and forming part of the present specification. These forms will now be described in detail, illustrating the general principles of the invention; but it is to be-understood that this detailed description .is not to be taken in a limitingsense, since the scope of the invention is best defined by the appended claims.

Referring to the drawings:

Fig. 1 is a fragmentary elevational View partly in section of the upper portion of a tool embodying the pres- .entinvention, showing parts of the tool as they would appear when running the tool .into the well;

Fig. 2 is .a .yiew similar .to Fig. 1 of the lower part of the tool, also showing parts thereof in the position assumed when running the .tool .into the well;

Fig. :3 a view corresponding to 1 shown in the upper portion of the tool as .it would appear when the tool is anchored in the well;

Fig. 4 is a view corresponding to Fig. .2 of the lower portion of .the ,tool, showing the parts thereof as they would appear when the tool is anchored in the well .and after {the sealant storage barrel has been emptied and the tool is in readiness for operation to scavenge residual sealant from theiool;

Fig. 5 is an enlarged fragmentary vertical section of the pump unit of .the tool showing the same connected to the tubular run in string;

Fig. -6 isan enlarged fragmentary sectional view of the portion of the tool mounting the anchoringmeans;

Fig. 7 is an enlarged fragmentary sectional view of the sealant storage barrel forming a part of the tool;

Fig. 8 .is a fragmentary sectional view of the lower portion of the tool embodying the packers and discharge duct for the sealant; and

Fig. 9 is an enlarged fragmentary sectional view of the lower portion of the sealant storage barrel showing the floating piston assembly at the bottom of its stroke with frangible closure in the piston assembly as it would appear when ruptured.

With reference to the accompanying drawings, it will be seen that a we'll'tool embodying the present invention generally includes a storage and dispensing unit A for the plastic sealant, a placement unit B by which the sealant is deposited at desired zones in the well, an anchoring unit C for releasably anchoring the tool to the casing D of the well, and a pump unit E. These units are combined to form an efficient tool adapted to be positioned in a well by means of a tubing string F. The tubing string F is connected with the pump so that the pump may be operated to 'force fluid under pressure into the unit A, thereby causing ejection of the sealant responsive to manipulation of the tubing string at the top of the well.

The tool is also provided with a tubular piston rod G, as part of the pump unit E, for connecting the pump piston H with the tubing string F. Locking means I provided to releasably restrain relative rotative movement of the piston rod G and pump cylinder K as well as relaa tive axial movement thereof. This locking means is locked and unlocked in a manner well known in this art, responsive to appropriate manipulation of the tubing string F.

The tool is assembled with the storage barrel L of the sealant storage unit A loaded to capacity and so that a floating piston assembly M in the barrel will be operable responsive to fluid under pressure derived from the pump unit E, to force sealant from the barrel through the placement unit B. With this arrangement, cracks or breaks in the Well casing, for example as shown at R in Figs. 4 and 8, or perforations therein which it is desired to seal, for example as shown at S in Figs. 4 and 8, readily may be sealed or other similar repairs elfected, with one run of the tool into the well, inasmuch as the sealant storage barrel L has an exceptionally large capacity. The construction and arrangement of the elements of the tool are such that the sealant storage barrel L is of such greater capacity than that of the pump cylinder or barrel that it is impossible to expel all of the sealant from the barrel with one complete down stroke of the pump piston. This greater capacity of the barrel L may be provided by making it of greater diameter than the pump cylinder or by making it of greater length than the pump cylinder and by increasing both the diameter and length compared to that of the pump cylinder.

Provision is also made for utilizing the pump unit E. to force fluid through the placement unit B to scavenge residual sealant from the tool when the sealant storage unit A has been emptied. In this connection it should be notedthat the floating piston assembly M is provided with closure means N which when opened, makes itpossible to force fluid from the pump unit B through the floating piston assembly for removing residual sealant from the tool.

The anchoring unit C is readily operable to anchor the tool at the desired locations in the well and as readily releasable, in both instances by manipulation of the tubing string F at the top of the well. Accordingly, with a large amount of the sealant stored in the tool, the

latter may be repeatedly positioned in a well and operated to place the sealant in a manner fulfilling the leaksealing or repair requirements of the particular well, without removing the tool from the well to reload it and then rerunning the tool into the well.

Referring more specifically to the drawings, particularly to Figs. land 7, the showing of the storage barrel L is intended to indicate that it has considerably greater capacity than the pump cylinder K, in this instance by reason of being of greater length than the pump cylinclosure N at the lower end of the tubular body. This closure is constructed and arranged to be ruptured only when the piston H is bottomed in the barrel as shown in Figs. 4 and 9. When the piston is bottomed, continued actuation of the pump unit E will develop a pressure discharge duct. As here shown, this means comprises a discharge tube 7 mounted within the mandrel 4 with its upper end opening into the barrel and its lower end communicating with a port 8 provided in the mandrel between the packers. An annular closure member 9 surrounds the upper end of the tube 7 to form a seal so that the sealant from the barrel will enter the tube 7 rather than the bore of the mandrel 4. The closure member 9 may be welded or otherwise secured in place to form the seal around the tube 7 and to close the upper end of the mandrel 4. The lower end of the tube may also be welded or otherwise secured and sealed to the mandrel around the port 8.

The mandrel 4 is open at its lower end and provided adjacent its upper end with a port 10. As the diameter of the tube 7 is such that well fluid may flow through the mandrel 4 by reason of the port 10 and open lower end of the mandrel, -a by-pass is formed around the

packers

5 and 6 to facilitate moving the tool through fluid in the well.

As here shown the anchoring means C is mounted on a sectional tubular mandrel 11 connecting the pump cylinder K with the sealant storage barrel L. The upper end of the mandrel 11 is coupled as shown in Figs. 3 and 6 by means of a coupling member 12 with the lower end of the pump cylinder K. The lower end of the mandrel 11 as shown in Figs. 4 and 7 is connected by a coupling member 12 with the upper end of the sealant storage barrel M.

The anchoring means C includes, as shown in Figs. 2, 4, and 6, a tapered slip expander 13 fixed on the upper end of the mandrel 1 1 in threaded engagement therewith.

' Slips 14 are'engsgedwim the expander in the conventional arrangement so as to be forced into anchoring engagement with the well casing D upon downward movement of the expander. The slips 14 are connected by links 15 with a collar 16 surroundings. tubular member 17 which latter telescopes the mandrel 11 as an outer section thereof. The upper end of the tubular member ,-17 is threadedly coupled as at 17' with the lower end of I the expander 13 and extends to a point adjacent the connection of the lower end of the mandrel 11 with sealant barrel L.

A mandrel :18 mounting drag springs 19in the conventional manner telescopes the tubular member 17 and is welded or otherwise fixed at its upper end to a coupling member 20 which latter is interengaged with the collar 16 so as to provide a rotative connection as at 21 between the mandrel 18 and tubular member 17.

A J-lock is provided to hold the slips 4 and expander 13 in relative positions in which the slips 14 are retracted so that the tool may be moved freely in the well. This spring mandrel 18 and a pin 23 carried by the tubular J-lock includes a conventional J-slot 22 in the drag efiective to rupture the'closure N, Whereby the tool may be operated as will be hereinafter described, for washing residual sealant therefrom.

As shown in Figs. 2 and 7, the sealant storage barrel L is connected at its lower open end with the upper end of a tubular circulation mandrel 4 for supporting

cup packers

5 and 6. These packers are axially spaced and arranged to seal against the casing to isolate a zone into which the sealant is to be deposited, for leak-sealing purposes.

Means are provided for communicating the isolated zone between the packers and exteriorly of the mandrel 4, with the lower end of the barrel L, in the form of a member 17 which in effect is a part of the mandrel 1-1. The J-lock' is released by rotating the string in a manner which will be hereinafter described, to provide for the setting of the slips. 7

The cylinder K of the pump unit E is connected with the tubular run-in string F by means of the tubular piston rod G which latter supports the entire tool through its connection with the pump piston H. At its upper end the rod G is connected by means of a coupling member 24 as shown in Fig. l with the tubular run-in string F. As shown in Fig. 5, the rod G is slidable through a packing gland unit 25 closing the upper end of the pump cylinder K. The pump piston H, consisting in this instance of a pair of piston cups 26, is mounted on the rod G at a point above the lower open end of the rod. With this arrangement, fluid is conducted into the pump cylinder K through the tubular piston rod, the fluid either entering the rod from the tubing string F or through intake means, to be hereinafter described, provided on the rod.

The locking means I includes a tubular extension 250 on the packing gland unit 25, having bayonet slots 25b therein .for reception of a locking pin 25c on-the piston .G. The pil 256 is moved from locking position -.shown in Fig. linto unlocked position shown in-Fig. 3 I and vice versa upon appropriate manipulation of thetubnc string F in a ma e wel know n thi ar T lo ing means I a ose ve as a c utch wh re y P mp che k a ve 30 s. pr vid d in he tu u a p on o a ia en the pump p ton fllahd hslo ad cent Po 3 in t o The pa 3, ssthmuh sate the int o of the .rod G with the space in the pump cylinder K above the piston H. These valves and ass oc i ated ports provide for he c a n o t e Pump sh E t a e? fl d un e pressure int the barrel L for operating the floating piston M. Another series of ports 32am provided inthe ubul piston d 6 above t parts 9 er bei a-partitio n 33 between the ports. 29 and 3 2. The ports -3 2 provide for introducingfluid into the space in the cas- -,-ing D from the tubing string when this is desired.

n the p s k f he Pum Pi to uid w l a ter the ports 29, open the check valyes 2 8 and 30 andpass .into the pump cylinder K below the piston H. Fluid the cylinder K above the piston H is' also displaced through the check valve 30 during the up stroke qflthe P ston Qn the down fstrolge of the piston 11, fluid vis-drawn thrhhs the upper h ck a elfia d passed through ,ports 31 into the pump cylinder above-the piston, while --th e piston forces the fluid below it through the 'mandrel 1l into the sealant-barrel .The check valve 30 closed by'fluid pressure-beneath it during-the down stroke of the piston H.

Operation The tool is prepared for operation by removing the sealant storage barrel L at the joint thereof with the mandrel 11 and then filling the barrel to capacity with the sealant in a manner prqyiding for the mounting of the floating piston M on top of the charge of sealant. After this loading operation, the sealant barrel is reassembled in the tool and the latter is run into the well 9n thetuhing string F. Well fluid encountered in lowering the tool, is by-passed through the mandrel 4, around the packers Sand 6.

D rin hi lowerin of thestool, the locking me n i and the J-

lock elements

22 and 23 are locked so that the piston rod G- and cylinder K are held against relative axial and rotative movement, and the slip expander and slips 14 are locked against relative movement which would move the slips out of the retracted position permitting thetool to be moved freely in the Well.

When the. tool reaches the position in the Well Where it is desired to deposit sealant from the barrel L into the zone between the packers and 6, the tool is anehored to the casing. This anchoring operation is effected by raising the string F slightly, then turning the string sufficiently in the appropriate direction to move the lock pin 250 so that the cylinder K will be correspondingly turned while the pin is free to move axially. This lifting and turning of the string F will cause a corresponding turning movement of the tool as a unit, except the drag spring supporting mandrel 18 which is rotatably coupled as at 21 to the collar 16. The collar 16 is rotated or turned with the tool relative to the mandrel 18 responsive to the aforesaid turning of the tubing string F, since the mandrel 18 is held against turning by the frictional engagement of the drag springs 19 thereon with the well casing whereby the J-lock pin 23 will move out of locked position in the slot 22 in the mandrel '18.

When the loci; pin Z Sc-and ,l-lock pin 23 are moved out of locking position, the tubing string F is lowered and the tool, excepting the drag springmandrel 18 and slips 14, are correspondingly lowered, thereby lowering the expander 13 and causing the slipsl t to be moved laterallyinto anchoringengagement with the well casing.

With the tool anchored in the desired position, the pump unit B may be operated as desired by reciprocating :ths iiib l t in F an Pam s G he h to-the-piston H, Thepurnp eyl-inder .K Intakes fluid in the manner hereinbefore set forth so that upon the down st o at the h manis fla s w l he forced ro vthe cylinder K through the mandrel 11 against the floating piston-M inthe sealant barrelL. This causes the piston M to move downwardly in the barrel L so as to force sealant through the discharge tube 7 .into the zone outside the mandrel 4 :and between the packer. The sealant thus discharged will fill and seal the break or perforations, or both, as the case may be, that are lo- ,cated in the isolated zone between the packers.

As the sealant employing is preferably a semisolid plastic having viscosity which retards appreciable-migration thereof relative tothe-brealc or perforation and casing area immediately adjacent the break or area, only that amount of sealant necessary to enter the break or perforation and to cover a solid area surrounding the break or perforations is required-in most instances. However, the large amount-of. sealant available in the barrel 1L makes-it possible-to provide asrnuch sealant .asrmay be required for repair purposes at. any given zone in-the well.

It should-be notedthat the. amountof sealant deposited -in.the wel ro he ool deps sl s n the du a of op t n of the p mp u t E- 4 cases wh e t e zone siderable length of the casing, the tool readily may bereleased, reanchored at selected. zones and operated to effect the desired sealing. This is made possible byemploying a sealant barrel of considerably greater capacity than that of the pump cylinder.

The sealant-material due to its viscosity will not gravitate through the discharge tube 7, particularly as this tube is of smaller diameter than the storage barrel vL.

After each sealant placement operation, the tubing string F may be lifted and turned to engage the elements of the lock means I and dispose the J-lock pin in locked position, at the same time raising the slip expander 13 to release the slips 14 from anchoring engagement with the well casing. The tool in this condition mayrnow be moved upwardly-or downwardly in the-well to a selected zone .to be treated and then anchored to the casing and operated to place the sealant as-desired in the new zone.

When thesealant barrel L has been emptied, any residual sealant in or on the tool that may set and clog the placement uni-t B or interfere with withdrawal of the tool from the well, may be scavenged fromthe tool. This washing of the tool is accomplished by continuing the actuation of the pump unit B when the' floating piston M is at rest at the bottom of the barrel L as shown in Figs. 4 and 9. The operator at the top of the well may readily determine when the floating piston M is at the bottom of the barrel L, by the fluid pressure increase reflected at the top of the well. Continuation of operation of the pump will build up a pressure while the piston M is bottomed, will develop a pressure that will rupture frangible closure N, thereby establishing communication between the pump cylinder K and the space in the casing between the

packers

5 and 6 and exteriorly of the mandrel 4. The pump unit B may now be operated to force fluid from the pump through the barrel L, the tubular member 1 in the floating piston M, the tube 7 and out into the space exteriorly of the mandrel 4. However, before this washing operation is effected, the tool should be lifted 0r tioned at selected zones.

J lowered to cause the packers to embrace a zone removed from the zone in which the seaiant has been placed, to avoid dilution or displacement of the sealant previously deposited.

It is important to note that throughout sealant placement operations such as may be effected with one run of the tool in the well, the floating piston M is progressively lowered, reaching the bottom of the barrel only when the last sealant placement operation is effected. The semi-solid nature of the sealant is such that after each placement operation, the floating piston M will be supported atop the column of sealant remaining in the barrel and will not force the sealant out of the barrel until the pump piston H is operated responsive to manipulation of the tubing string. One down stroke of the pump piston H will not move the floating piston a complete down stroke. In other words the barrel L cannot be emptied with one down stroke of the pump piston,

due to the barrel having a considerably greater capacity than the pump cylinder. With this arrangement, the weight of the tubing string F aids in operating the pump unit E but does not cause an operation which would expel all of the sealant with one downward stroke of the pump piston.

The present invention also embodies a novel method of placing a plastic sealant at selected zones of a cased well, with one run into the well of apparatus by which the method may be carried out, whether the apparatus 'includes the tool here shown, or other means which obviously could be employed.

In carrying out this method an enclosed supply of the sealant is combined with means for subjecting the supply of sealant to fluid pressure impulses. This supply and the means for producing the fluid pressure impulses are lowered into the well on a run-in string and posi- The discharge and placement of the sealant is effected and controlled by actuating the fluid pressure impulse producing means so as to subject the sealant supply to series of fluid pressure impulses effective to discharge from the supply responsive to each series of impulses, a portion of the supply of sealant.

After an initial placement of sealant from the supply at a selected zone, the enclosed supply and impulse producing means may be repositioned in the well to treat another zone. Following this repositioning, the supply may be subjected to another series of fluid pressure impulses which will result in the placement of another portion of the sealant for leak-sealing, casing repair or other purposes, as required. This repositioning and discharge of sealant may be repeated until the supply is exhausted, thereby making it possible to meet the requirements of a particular well without withdrawing from the well for reloading purposes, the apparatus employed to carry out the method.

It will now be apparent that this method makes it possible to apply plastic sealant to a cased well in a much more eflicient and economical manner than heretofore. This is dueto the provision for carrying into the well a supply of sealant estimated to meet the requirements of the particular well, also due to employing as a part of the apparatus required for carrying out the method, means operable in the well by reciprocation of the runin string for subjecting the supply of sealant to series of fluid pressure impulses to control the discharge and placement of the sealant.

I claim:

1. A tool adapted to be positioned in a cased well on a tubing string and operated for placing a sealant in the well comprising: a reciprocable piston pump unit operable for impelling fluid therefrom; means for connecting said unit with the tubing string providing for operation of the pump unit upon reciprocation of said string; means connected with said pump unit operable responsive to manipulation of said string for releasably anchoring said unit to the well casing; a sealant storage barrel adapted to be filled with the sealant before the tool is run into the well; means connecting said barrel with said pump unit for conducting the impelled fluid into said barrel for forcing sealant from said barrel; said barrel having a capacity greater than that of said pump unit so as to contain a greater amount of sealant than can be forced therefrom responsive to one complete fluid impelling stroke of the pump unit; and sealant placement means connected with said bar-rel for depositing sealant at a selected zone in the well.

2. A tool adapted to be positioned in a cased well on a tubing string and operated for placing a sealant in the well comprising a reciprocable piston pump unit operable for impelling fluid therefrom; means for connecting said unit with the tubing string providing for operation of the pump unit upon reciprocation of said string; means connected with said pump unit operable responsive to manipulation of said string for releasably anchoring said unit to the well casing; a sealant storage barrel; a floating piston in said barrel; means connecting said barrel with said pump unit for conducting the impelled fluid into said barrel for moving said piston to force sealant from said barrel; said barrel having a capacity greater than that of the pump unit so as to contain a greater amount of sealant than can be forced therefrom responsive to one complete fluid impelling stroke of the pump unit; and sealant placement means connected with said barrel for depositing sealant at a selected zone in the well casing.

3. A tool adapted to be positioned in a cased well on a tubing string and operated for placing a sealant in the well comprising a reciprocable piston pump unit operable for impelling fluid therefrom; means for connecting said unit with the tubing string providing for operation of the pump unit upon reciprocation of said string; means connected with said pump unit operable responsive to manipulation of said string for releasably anchoring said unit to the well casing; -a sealant storage barrel; a floating piston in said barrel; means connecting said barrel with said pump unit for conducting the impelled fluid into said barrel for moving said floating piston to force sealant from said barrel; said barrel having a capacity greater than that of the pump unit so as to contain a greater amount of sealant that can be forced therefrom responsive to one complete fluid impelling stroke of the pump unit; sealant placement means connected with said barrel for depositing sealant at a selected zone in the well casing; means providing a passage through said piston; and means closing said passage operable when said barrel has been emptiedfor opening said passage.

4. A tool adapted to be positioned in a cased well on a tubing string and opera-ted for placing a sealant in the well comprising a reciprocable piston pump unit; means for connecting said unit with the tubing string providing for operation of the pump unit upon reciprocation of said string; said pump unit having means for intaking fluid and impelling fluid therefrom; means connected with said pump unit operable responsive to manipulation of said string for releasably anchoring said unit to the well casing; a sealant storage barrel which is filled with a sealant when the tool is run into the well; a floating piston in said barrel; means connecting said barrel with said pump unit for impelling fluid from said pump unit into said barrel for moving said piston to force sealant from said barrel; said barrel having a capacity greater than that of the pump unit so as to contain a greater amount of sealant that can be forced therefrom responsive to one complete fluid impelling stroke of the pump unit; sealant placement means connected with said barrel for depositing sealant at a selected zone in the well casing; said piston having a passage therethrough for communicating the storage barrel above the piston to said sealant placement means; and closure means for said passage operable to open said passage in response to fluid directedtliereagainst by said pump unit after the discliargeof" all of='said sealant from-said barrel.

A to'ol adapted to be-positioned in a= casedwell on a 'tubing'string and operatedforplacing asealant in the well comprising: -a' storage barrel for-- the sealant; a tubular mandrelconnected withsaid barrel; packersaxially: spaced'on said mandrel forsealing against the well casing; means embodiedin said mandrel providing a by--'p'a'sspassage-cominunimting a't*its" ends'with the space exteriorly' of said mandr'eliabove mam-new said packers; means-'providinga ductfor discharging-sealant from said barrel into= tlre space between said packers exteriorly of said" mandrel; afloa'ting"piston 'movable iirsaid barrel for expelling sealant through said duct; a pump cylinder Having fluid intake means; a second-' tubular mandrel connecting said"cylinder-with said barrelj" a pump piston operablein said cylinder t -=rerefima= through said -second mandrel for" actuating said floatiiig' piston; a seatfor said heating pistonat the bbttonfof said b'arrel; said piston 1 having apassage th'eretlirougli;- closure means in said passage Openable by fluid pressure'from said pump upon seatingof said floatingpistonoirsaid seat; a'reciprm cablepistorrrod connectw-with said piston;said-rod hav-' ing means providing for connectifiguhcreof wifli the tubarise-naming mean's on o'iie" of said nrandi'elia' for: anchoring thetool to well 1 casing.

6. A tool adapted tobepositionediir-zrcased well on artubing-s'tring'and operated for placing a sealant inthe welhcor'r'rprisingz a sbtora'ge -barrel forthesealant; a t-ulana lar mandrel connected with said barrel; packers axially spaced our-said mandrel sfor"sealinggagainst;- the-well casing; means embodied in saidlmandrel providing a by-pass passage communicating at ifs ends the space ext'eriorly of--' said mandrel-above and below said packers; meansdarried by-said mandrel prbt iding a ductfor discharging sealant-fromsaid-barrel into tlie space=between sa'icl pa'ckus exteriorlyofsaidmaridibli a floatingz piston movable in said barrel for expelling sealant through said duct; a pump cylinder having fluid intake means; a second tubular mandrel connecting said cylinder with said barrel; a pump piston operable in said cylinder to force fluid through said second mandrel for actuating said floating piston; a reciprocable piston rod connected with said piston; said rod having means providing for connection thereof with the tubing string; means providing a passage through said floating piston; a frangible closure sealing said passage; and anchoring means on one of said mandrels for anchoring the tools to the well, casing.

7. A tool adapted to be positioned in a cased well on a tubing string and operated for placing a sealant in the well, comprising: a storage barrel for the sealant; a tubular mandrel connected with said barrel; packers axially spaced on said mandrel for sealing against the well casing; means embodied in said mandrel providing a bypass passage communicating at its ends with the space exteriorlyof said mandrel above and below said packers; means providing a duct for discharging sealant from said barrel into the space between said packers exteriorly of said mandrel; a floating piston movable in said barrel for expelling sealant through said duct; a pump cylinder of less volume than said storage barrel; a second tubular mandrel connecting said cylinder with said barrel; a pump piston operable in said cylinder for forcing fluid through said second mandrel for actuating said floating piston; a tubular piston rod extending into said cylinder and connected with said pump piston; fluid intake means for said pump cylinder, embodied in said rod; means on said rod providing for connection thereof with the tubing string; and anchoring means on one of said mandrels operable to anchor the tool to the well casing.

8. A tool adapted to be positioned in a cased Well on a tubing string and operated for placing a sealant in the well, comprising: a storage barrel for the sealant; a tubular mandrel connected with said barrel; packers axially spaced on said mandrel for sealing against the Well casing; means I6 embodied in said' mandrel providin'g a? by-pa-ss around said packers; means providing a duct for' discharging sealantfrom said barrel intothe space betweensaid packers exteriorlyof 'said mandrel; a: floatingpiston-movable in said barrel for expellingzsealantithrough said duct; a pump cylinder; a second tubularmandrel connectingsaid cylinderwith-said' barrel; a pumppiston' operable in said cylinder for forcingfl'uid through said second mandrel for actuating--said floating pistonra tubularpiston rod extendinginto'saidcylinder andconnected' with said pump piston; fluid intakemeans=forsaid pump cylinder, embodied insaid rod; means on said-rodprovidingfor 'con nection thereof" with thetubing string; anchoring means on' one of said mandrels operable to anchor thetool to the welloasing; means providing a passage through said floating piston;'a frangible member closing said pas sage; said-'frangible member being subject torupture' only when said piston-is at rest' atthe bottom of its stroke in-said barreli- 9.- A tool adapted to=be positioned in a-cased well on a-tubing string' and" operated for placing-a sealant in'the well; comprising: a storage barrel for the sealant; a tubular-mandrel connected 5 with" said bar'reli packers axiallyspaced onrsaid' mandrel forsealing against" the wel-l' 'cas ing; meansembodied in said mandrel providing a-by-p'ass passagecomrmmicating'atitsends=with the space exterior 1y of said mandrel above and beldw'said -packers;.means providing-a duct for discharging i sealant fromsaid barrel into'tlre} space between said packers exteriorly' of: said mandrel; a floating piston movable) in said barrel for expelling sealant through said duct;- a. pump cylinder 'cf less vdlirme than s'a'idi storage barrel-' and having; fluid iiitale me'ans; second tilbular-mandrelf. connecting said cylinder with said barrel; a pimp pistorr operable-in said to force 'fltiid' through said second mandrel for actuating said floating piston; a reciprocable" piston rod connected with said piston; said rod having-.- means pro viding for connection thereof with the tubing string; and anchoring means mounted on said second mandrel operable for releasably anchoring the tool to the well casing.

10. A tool adapted to be positioned in a cased well on a tubing string and operated for placing a sealant in the well, comprising: a storage barrel for the sealant; a tubular mandrel connected with said barrel; packers axially spaced on said mandrel for sealing against the well casing; means embodied in said mandrel providing a bypass passage communicating at its ends with the space exteriorly of said mandrel above and below said packers; means providing a duct for discharging sealant from said barrel into the space between said packers exteriorly of said mandrel; a floating piston movable in said barrel for expelling sealant through said duct; a pump cylinder; at second tubular mandrel connecting said cylinder with said barrel; a pump piston operable in said cylinder for forcing fluid through said second mandrel for actuating said floating piston; a tubular piston rod extending into said cylinder and connected with said pump piston; fluid intake means for said pump cylinder embodied in said rod; means on said rod providing for connection thereof with the tubing string; anchoring means on said second mandrel operable to releasably anchor the tool to the Well casing; a tubular member carried by and extending through said floating piston; and a frangible member closing said tubular member; said frangible member being subject to rupture when said floating piston is at the bottom of the stroke.

11. A tool adapted to be positioned in a cased well on a tubing string and operated for placing a sealant in the well, comprising: a storage barrel for the sealant; a tubular mandrel connected with said barrel; packers axially spaced on said mandrel for sealing against the well casing; means embodied in said mandrel providing a by-pass passage communicating at its ends with the space exteriorly of said mandrel above and below said packers; means providing a duct for discharging sealant from said barrel into the space between said packers exteriorly of said mandrel; a floating piston movable in said barrel for expelling sealant through said duct; a pump cylinder of less volume than said storage barrel; a second tubular mandrel connecting said cylinder with said barrel; a pump piston operable in said cylinder for forcing fluid through said second mandrel for actuating said floating piston; a tubular piston rod extending into said cylinder and connected with said pump piston; fluid intake means for said pump cylinder embodied in said rod; means on said rod providing for connection thereof with the tubing string; anchoring means on one of said mandrels op erable responsive to rotative and axial movement of said mandrels, cylinder and barrel to releasably anchor the tool to the well casing; and clutch elements on said cylinder and said rod cooperable to provide for said rotative and axial movements responsive to corresponding rotative and axial movements of said tubing string.

12. A tool for placing a sealant in a well comprising: a barrel for containing the sealant; said barrel having a discharge opening; a floating piston operable in said barrel to force sealant through said opening; placement means connected with said barrel operable for conducting sealant from said opening to a selected zone in the .well; pump means connected with said barrel operable for directing fluid under pressure into said barrel for moving said floating piston to force sealant from said barrel through said placement means; said floating piston having a passage therethrough for communicating the space in the barrel above the piston with said discharge opening; and a closure for saidpassage operable to open said passage in response to fluid pressure directed thereagainst by said pump means after the discharge of all of said sealant from said barrel.

13. A tool for placing a sealant in a well comprising: a barrel for containing the sealant; said barrel having a discharge opening; a floating piston operable in said barrel to force sealant therefrom; placement means connected with said barrel operable for conducting sealant from said opening to a selected zone in the well; pump means connected with said barrel operable for directing fluid under pressure into said barrel for moving said floating piston to force sealant from said barrel through said placement means; means at the lower end of said barrel against which said piston will be bottomed when all of said sealant is discharged through said opening; and said floating piston having a passage therethrough; and closure means for said passage openable in response to fluid pressure directed thereagainst by said pump means after the discharge of all of said sealant from said valve.

14. A tool for placing a sealant in a well comprising: a barrel for containing the sealant; said barrel having a discharge opening; a floating piston operable in said barrel to force sealant therefrom; placement means connected with said barrel operable for conducting sealant from said opening to a selected zone in the Well; pump means connected with said barrel operable for directing fluid under pressure into said barrel for moving said floating piston to force sealant from said barrel through said placement means; means in said barrel against which said piston will bottom when all of said sealant has been discharged from said barrel; means providing a passage through said floating piston; and a frangible member closing said passage; said frangible member being rupturable responsive to fluid pressure derived from said pump means when said floating piston is bottomed in said barrel.

' References Cited in the file of this patent UNITED STATES PATENTS 2,055,515 Yarbrough Sept. 29, 1936 2,077,022 Spencer et al. Apr. 13, 1937 2,387,002 Bannister Oct. 16, 1945 2,757,742 Tucker Aug. 7, 1956 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No 2954 827 October 4, 1960 Basil W. Wheeler It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column .4, lines 51 and 52 beginning with "This spring mandrel 18" strike out all to and including "the mandrel 11, in line 54, same column, and insert instead This J-lock included a conventional J-slot 22 in the drag spring mandrel l8 and a pin 23 carried by the tubular member 17 which in effect is a part of the mandrel l1.

Signed and sealed this 11th day of April 1961.

(SEAL) Attest: WIDER ERNEST 5 ARTHUR W. CROCKER Attesting Ofiicer Actmg Commissioner of Patents