US2644528A - Booster device for operating well tools - Google Patents

Description

July 7, 1953 T. M; RAGAN BOOSTER DEVICE FOR OPERATING WELL TOOLS Filed July 14, 1947 Patented July 7, 1953 BOOSTER DEVICE FOR OPERATING WELL TOOLS- Thomas M. Eagan, Downey, Calif., assigner to Baker Oil Tools, Inc., Vernon, Calif., a corporation of California Application July 14, 1947, Serial No. 760,851

. 16 Claims. (C1. 166-11) This invention relates to well tools, and more particularly to the operation of mechanisms forming part of such tools, which are especially employable in connection with the cementing, acildizing, washing, production, etc, of oil and gas we s.

Certain well tools depend upon the engagement of devices with the wall of a well conduit, such as a well casing or liner, for eiecting operation and control of the tool. For example, a drag device may engage a wall of a well casing, and through its resistance to movement within the casing produce operation of other parts of the well tool, such as the movement of slips and packing members from retracted to expanded condition against the well casing, or the opening or closing of a valve mechanism.

The frictional force available in effecting movement of such elements may sometimes be inadequate, resulting in inability to operate the well tool in the desired manner. This may be pronounced in connection with a valve device operable to control the flow of cement slurry pumped down a tubing string for deposition behind the well casing and into the formation. Specifically, a well tool may embody a downwardly seating valve, which is movable upwardly to open position in dependence upon movement of the tubing string and the frictional engagement of a drag device with the wall of the well f1.1

casing. If it is desired to ush a relatively extended head of cement slurry, or the like, from the interior of the tubing string, such head may prevent opening of the valve device, since it imposes a much greater force on the valve tending y to keep it closed than the frictional force of the drag device against the casing wall.

Accordingly, it is an object of the present invention to provide a Well tool having relatively movable elements, in which the forcel available for moving such elements is multiplied.4

Another object of the invention is to multiply the friction force of a drag device against the wall of the well casing, and utilize the enhanced effort for eiecting movement of the well tool parts.

Still a further object of the invention is to pro; vide a valve controlled well tool embodying a valve operating device capable of multiplying or boosting the force available for moving the valve between open and closed positions.

Yet another object of the invention is to provide a hydraulically controlled well tool valve apparatus embodying a hydraulic booster for effecting operation of the valve.

This invention has other objects which will become apparent from a consideration of the embodiment shown in the drawings accompanying and forming part of the present specification. This form will now be described in detail to illustrate the general principles of the invention, but it is to be understood that such detailed description is not to be taken in a limited sense, since the scope of the invention is best dened b the claims appended hereto.

Referring to the drawings:

Fig. 1 is a longitudinal section through a Well tool located in a well casing. 1

Fig. 2 is a longitudinal section, onan enlarged scale, through a valve device forming part of the tool disclosed in Fig. 1 with the valve illustrated in open position.

Fig. 3 is a side elevation of the lock device for determining the operation of parts of the tool.

The invention is disclosed in the drawings, as applied to a well packer of a, type designed to force uid under pressure through the perforations of a well casing. It is to be understood,

however, that it has application to other types of well tools.

Specifically, the well tool consists of a body III, suitably secured, as by threading, to the lower end of a string of tubing or drill pipe Il, by means of which the tool is conveyed through the well casing I2 to the desired operating point therein. The body consists of an upper body member I3, a lower body member I4, and an intermediate body member I5 connecting the upper and lower members together in spaced relation. The generaltype of well tool shown is a packer described and claimed'in the application of Charles E. Costello, Serial No'. 391,548, filed May 2, 1941, for Well Devices, now Patent No.

The upper and lower portions of the tool are substantially duplicates, being connected to the intermediate body member I5 in opposed relation. A description of the upper portion should suffice for the lower portion as well.V

The upper body member I3 includes an elon.-

gate mandrel or nipple I6 having a sub I1 screweded for slidable sealing engagement with the wall of the well casing I2 to prevent both upward and downward flow of fluid betweenthe upper body member I3 and the casing Wall.

sub I8, containing a rod packing pressed in'.V leak-proof engagement against. the exterior of. the tube by a suitable packing nut 26, to preventdownward flow of fluid through the annulus 2l beyond the flange 24.

As noted above, the construction ofthe-lower tool portion is substantially the same as the upper, with the parts facing in theopposite-direction, so that fluid passage between the lower body member Il! and casing wall in both upward `and downward directions is p-revented. Upward ow'of fluidI through. thev lowerf'annulus; Z'Ia -beyondfl the flange 25J-'a' is prevented*` byA the;y ange 24a; packing 25o; and packing nut. 26a surround'- ving;thel'owerbyJ-pass tube 20a. For convenience in-videsignati'on, theloawer parts are numbered'the same-as the corresponding upper parts, with the suifix d added. Y Y The upperandlower tool portions are held together in spaced relation by the intermediate `body member I5, which actually formsV parti of the by-passfof thet'ool. This'intermediate body member is secured tothe upperv and lower subs I8; I8a, and may'bemadeof any length desired, depending upon-the-spacingrequired'between the upperfan'd lowerpackingcups 01, Sec. The bypass around the packings` extends from a point outside-the toolbelow the lowerrnost'packing S Ia toaV point outside the tool above theV uppermost packing* 6I. More Jspecically, this by-pass `passage-is constituted by thev lower T 22a, lower by-pass tube-22a; intermediate body member I5, upper'by-pass tube 2o, and upper by-pass T 22. The upper sub- I8V is provided withl one-orA more upper outlets or ports 2'I adjacent the packing cupplil'and-` flange 24 andthe lower sub lea is similarly provided with onev ormore lower outlets or ports 27a adjacent the lower packing cup 66u' and flange 24a. Fluid cannot pass directly from the uppe'rbody'annulus 2l to the lower body annulusY 2id because of the anges and packings aroundv the'by-pass tubes, but must pursue an indirect course; The fluid may be pumped downwandlythroughthe tubing II into the upper body member annulus 2|, exiting through; the upper ports 2'1' into the localized annularv zone Zd'fdenedby the upper. and'v lower packings 60,' Bild, and by the intermediate body ,memberl and casing I2. This uid may flow downwardly through the zoneY 28 and enter the lowerbody memberl I 4 through the lower ports 21a, Qwhere theuid can pass downwardly through the annulus 2m around the lower by-pass. tube 20u-into. thevalve body or housing 29Y screwedinto the, lower. endof the lower sub IIa.` The fluid mayr then pass through the valveoutletsor ports 3.D;in.the,hou`sing to the exterior 23a.of. the tool belowthe lower packing cupr la, from where it mayfflow upwardly intothelower. by-pass. T 22d, through theflower by-pjass tube 20a, intermediateby-pass memberV l5, tube 20 and upper bypass T 22, intoy the tubing-casing annulus 23 aboverthecupperpacking'cup 6I.

` llhexallowingo the-uidto pursue the-course just described isa'dependent uponthe control of the fluid flow through the valve ports at the out". through the ports 30.

lower end of the tool. Such control is obtained through a Valve mechanism, including the valve body or housing 29. This valve mechanism includes a valve seat 3i clamped between vthe upper and lower portions 29a, 29h of the valve housing, which arethre'adedly secured together; The seat is engageable by a valve head 32' upon downward movement of the latter. When such a Valve head is in engagement with the'valve seat, fluid cannot` flow.- downwardly through the latter and However, in the specic valve disclosed in the drawings, fluid may fiowfin thereverse ydirection through the ports 30 an'dfupwardly` through the seat 3 I, since the force of fluid moving in such direction will automatically disengage the head 32 from the seat. The valve mechanism further includes a valve stem or piston rod 33 threadedly secured to the head 32 and extending-1downwardly through the seat .Il into@ a` large 'cylindery B vfor-med 'on' an intermediate portieri-ofthe valvehousing 29', 'the rod being integral'with, or `otherwise secured to, apist'on 35 carrying' suitable piston rings or-'side seals 36I adapted? to''engag-'e the wall' of the large cylinder. The valve housing or body 29 includes a lower cylinder" 3T off a substantially smaller diameter than the'largerrcylinderd', in whichfa small'4 diameter elongate-piston 38? is slidable, such piston carrying suitableLs-idefseals or piston rings 39 engageable with v the waill of-thef small cylinder toprevent leakagetherebetween. y

The space` 4Q; 4I between the-largeiandsmall pistons 3o'"within thev large and Vsrnallfc'zylinders- 3E, 3l i'siill'ed'with a suitable liquid`42l, such as light oil, which may be inserted through a ller or bleefder'hol'e-ISL which is then closedby Ia plug Mi. y l v K The lower end of the pis-ton 334 is` threaded into the lowerhead iof'a'lockv sleeve 4,6 extend,- ing upwardly aroundthe: piston- 38' and` slidable along the exteror'of the smjall cylinder 371 This sleeve has aV generally L-shaped-` slot therein, including` vertical-and horizontal' slot portions 'I 4T, i8hv adapted to receive a lock pin di?` secured to the small diameter cylinder 3T'. The rod 50 of adrag device 5 I depends from the sleeve head t, having a collar 5,2 and guide 53 threaded on its lowerl end; YSuitable dragv springs [54' are secured to the collar 52being frictionally engageable with the wall of the well casing I2. 'Such springsY extend' upwardly along. the rod 50. and are connected attheir upper ends to. an. upper collary 55slid'able alongthe rod.

The drag.springs;52i1exertacertain frictional force againstthewall of. thefwell casing, I2 and this. frictional, forceis availed of. to. move. the valve head 32'.' upwardly from. the. valve scatti. The=tubular string, I.I. and valve' housing. 2.9.connected thereto. are. movabley as. al unit-longitudinally of the small. piston 318locksleevedS-land dragl device 5l., in order to. effectv movement of the valve, .hea-d 32 relative to its. coopera-ble seat 3i. If. the;v lock pin t8, is. disposed within the longitudinal.portionzrl` of the L-slot'the housing 29 body .lil1 andl tubing string IfI- may be moved as aunit with. respect. to thefaforementioned4 lock sleevesmall piston andz drag device. Downward movement of the rstffmenti'oned parts 29, It', II produces relativeupward' movement oil the piston 38 within. thel smaller cylinder 3??, since movementy of they former: is resistedv or .prevented by the frictional engagementof'the. dragV springs 55 with'the wallv of; thewellf casing, lf2. Accordingly,

a unit pressure is developed inthe entrapped liquid 42 within the cylinders 34, 31, which is exerted overl the entire area of the largepiston 35 in an upward direction, elevating 'the piston 35 and its attached head 32 from the valve seat 3l. Conversely, upward movement of theA tubue lar string II, tool body I0 and valve housing 29 effects a relative lowering movement of the small piston 35 within its cylinder 31, and relievesjthe uid 42 of pressure, allowing the valve head 32 to re-engage its seat. Y'

Since the Vcross-sectional area of the small diameter piston 38 -and cylinder 31 is substantially less the cross-sectional area of the larger diameter piston 35 and cylinder 34, the force imposed by the small piston 38 on the liquid 42 is multiplied many times 'upon the large piston 35, the multiplication in force being in the ratio of the large cylinder diameter to the small cylinder diameter. In other words, the frictional force of the springs 54 against the wall of the casing I2 is multiplied to the extent indicated upon the large diameter piston 35, and thereby provides a much greater elevating force upon the valve head 32.

When it is desired to maintain the valve head 32 elevated from its seat 3| upon raising of the tubing string II and well tool within the well casing I2 to hold the valve in open position, the tubing string II, tool body I0 and housing 23 can be lowered until the lock pin 49 is aligned with the horizontal slot portion 48 of the lock sleeve 43, and the tubing string II then turned lto the left part of a revolution to locate the pin 49 within such horizontal portion 48. During the lowering movement of the tool parts and tubing string, the pressure created in the entrapped iiuid 42 raises the head 32 from its seat 3i, and upon locking of the pin 49 within the horizontal slot portion 43, the fluid 42 in the cylinders 34, 31,'as well as the pistons 38,35 and'valve head 32 are maintained in such elevatedY position, enabling the well tool to beelevated in the well casing. I2 without,V permitting the valve head .to `close against its seat. ..1 i f A representative use of the booster mechanism is in connection with the cementing of awell casing. The tool disclosed in Fig. l is lowered through the well casing I2 until the inner'packing cups 60 59a are disposed on opposite sidesfof casing perforations 59, through whichfcement slurry or other cementitious` material is 'to be ejected. During this running-inoperation, the drag springs 54 resist'lowering'of `the piston 33 and lock sleeve 46 within the casing, and, accordingly, the valve head'32 occupies an vupper position with respect to its seat 3l. Actually, in the specific design disclosed in the drawings, it is immaterial what position is occupied bythe piston 38 during the running of the tool within the well casing, since the 4valve head can automatically elevate from its seat and permit the uid in the well casing to enter the tool through the ports 39. In any' event, during' loweringof the tool in the well casing, the Vrelative upward movement of the small piston 33'4 within the circulating fluids -may be pumped down the tubing string II with the valve in its open posi above the upper packing member 61 for con? tinued Vupward movement through suchv annulus to the top of the well bore.

A charge of cement slurry may be started down the tubing string II and when its lower end is near the well tool, the tubing string may be elevated several inches, say two or three inches; to move the valve housing 29 upwardly with respect to the piston 38 and lock sleeve 46, as permitted by the disposition of the lock pin 43 within the longitudinal slot portion 41 of the look device, since the piston and lock sleeve are prevented from moving upwardly by the drag device 5I.

Such upward movement relieves the entrapped liquid 42 in the cylinders 31, 34 of pressure and permits the fluid in the casing and well tool to seat the head 32 downwardly against the valve seat 3i preventing further downward passage of uid around the valve head 32 and out through the ports 30. In other words, the ports 30 are closed to the passage of uid between the interior of the well tool and the exterior of the well tool below the lowermost packing Gla.

Theeement slurry passes from the lower end of the tubular string I I, through the upper annulus 2 I in the body and out through the'uppe'r ports 21, being forced under pressure throughthe casing perforations 59 for deposition behind the well casing I2. Such cement slurry cannot flow through the lower ports 21a into the lower body member I4, since the valveis in closed position and the fluid in the lower .portions of the body member I4 is prevented from flowing down and out through the ports 39.

Following deposition of the required amount of cement slurry through the perforations 59, any excess may be flushed from the tool by lowering the tubular string II, and the tool body I0 and valve housing 29 attached thereto, several inches, to eieot relative upward movement of the piston 33 within its cylinder 31, the movement of such piston being transmitted through the entrapped body of oil 42 tothe large diameter piston 35', causing the latter to move upwardly, and corre'- spondingly moving the valve vhead 32 from its seat 3|. If desired, the lock pin 49 at the lower end of the longitudinal slot portion 41 may be moved into the horizontal slot portion 48 of the'lock sleeve 46 to prevent inadvertent elevation of the small cylinder 31 with respect to the small piston 33, which would permit the valve head 32 to re# engage its seat 3l.

` Washing fluid' may now` be pumped down the` tubular string I i, forcing the cement slurry ahead of it and causing it to flow through the upper annulus `2| and upper port 21 into the localized zone 28,l then through the lowerY port 21a and lower annulus'2 Ia, and around the valvehead 32,

to discharge 'through the valve ports` 39,' where#v Y upon the excess cement slurry followed by the washing :duid `may ow through the bypass pas,- sage 22a, 2011,15, 29, 22 into the annulus 23 above the upper packing 6I, for passage to the top of the wellbore and appropriate disposal. A

The cement slurry may also be disposed of by Z circulating the washing fluid in a directionr re.- versely toY that :described byr initially-pumping it down. the,` tubingrcasing annulusA 2 3 the washing fluid passing throughthefby-pass passage Vand' the ports 3i) for upward nowing aroundthe valve head 32;, body passages Zia, 2'l and pcrts 27a, 2l into the'tubing string H, carrying the excess cement slurry'in the tubing string lahead: ofit to the top ofitheV Wellbore.k l K Inthe event that the; excess cementjslurry in theftubing stringis to be disposed of bypumping the Washing: fluid: downthe. tubular string il, conditions sometimeslrender. it difficultl to relatively movethe valve Vhead 32; or equivalent'valva to open position. For example,in the event'that there is an extended` column of excess., cement slurrypresent in theV tubingstring of, say, 1,090 feet; theV hydrostatic head of such cementl slurry acting downwardlyon the valvevmember exerts a. downward closing force thereon whichV may fbe substantially greater ,than the forcefof' friction ofthe drag springs 513 against the wall of the well casing i2. Downward movement ofv the tubing string H, and attached body I and valve hous ing: 29, might not,ttherefore, resultrin-opening of the valve, if only the frictional forceof thefdrag device against the casing l2 were available for directtransmission to the' valve head 32. However, by virtue of the presentiinventi'on, the frictionalforce of such drag springs is multiplied many times, thereby making it possible to move the valvexhead 32 upward even with a. very substantial hydrostati'ciheadi of cement slurry imposed thereupon. Y

AsV Wasrnoted above, the, area Arof cylinder is considerably less than the area AB of the large cylinder. As a result, the small piston 38 can function to create a maximum, unit-pre sure inftheoil i2 kWithin .the cylinder spaces dll', lli depending upon theimaXimum frictional` force exerted by the drag springs 54 against .thefwallpof thecasing; This unit pressure is then imposed upon the large diameter piston 35, and since the latter has a much greater areapthanthe' smaller piston, a muchgreater total force is available to elevate the piston 35 and the valve-head 32 than would be available if the small piston 38 were mechanically connecteddirectly to the valvehead 32. In effect; the small piston. 38 and small cyl- .inder 3.1 constitute auid pump `for 'generating pressurez'm the liquidllZ within the-cylinders 31, 3G, and the large piston 35 andlarge cylinder 3e constitute a fluidrmotor receiving such liquid un.- der` pressure and employing such pressureifor ,operatin'g ya' well device in thisparticular instance, atvalve member.;`

After the cementing operation. hasbeen come pleted,vthe tubular string Hytool body lil and valveV housing 2S may be lowered', `which causes the'lfluidlpump 3l, 3.8 to operate tor elevate the head 32 from its seat3 i, whereupon the lock pin 49 can be turned into the horizontal lock portion 68. of its -cooperable sleeve 5 and the entire tool then elevated from the well casing I2, the lockinghof the tool preventing bleeding of the oil 42 from the large cylinder 312 into the small cylinder 3'l'sinee downward movement of the small piston'within its cylinder is prevented. Accordinglm, duid may pass from Within the Ytubular stringv Il through thev tool body l@ and around the valve heady 32 for discharge throughtheports 30v to a point below the-welltool. l

While the invention has been described with particular reference to a valve device, .it is to beunderstoodthat it may be .employed in general Vtime Smau Y posedin said Well bore, agfluid motorengageable as a force. multiplier, for increasing; thee-effort available in operatingv Well .tool parts.

It is accordingly,l apparent that aV well tool hasvr been: provided, which the. force available for operating WellV parts has been considerably multiplied,and which, when speciiically related to av valve device, for a Well tool, overcomes to alarge extent the-pressure conditions Within a tool tending; to prevent operation of theI valve device..V Y Y Having thus describedmy invention, whatY I claim and desireto secure by Letters Patent is:

1. In a subsurface vvellltool:` relatively movable parts cooperable with each other to perform. a function in a well bore while disposed in the Well. bore; meansfor effecting relative movefV ment,v between said parts comprising a iiuid stantially less than thej-cross-sectional `pressure actuatable. area of said first cylinder member; a fluid in both of said cylinder membersyand means in the; well bore connectedv to a member of one oi said mechanismsfor bodily movingsaid memberA of said; one of saidV mechanisms with respect to a member of the, other of saidmechanisms to generatexa,pressurein; said uid; Y

2. A well t'ool adaptedtobe loweredin awell bore .Y on a running-in. string, including relatively movableY partsl cooperable` with each other to perform a ,functionin said well bore while diswith one of said parts to move the-,same with respect to said other part, a fluid pump fluidly communicable with said motor, the pressure effective rcross-sectional area .of said pump; being substantially lessr than that, of said. motor,Y and means connected to anv element of; said pump and operable in the-.well boreffor positivelyY displacing and` bodily moving said pump element tor develop al fluid pressure inv said pump' and in saidmotor tomove said one of said parts.,

L3. A welltool fadaptedto be lowered in awell bore on a runningein string,in'cluding, relatively movable parts( .cooperablewith each other to performfa functioniin said Well bore while disposed in said well Y bore, l a iiuid motor engageable with' oney of .saidY parts tov move the same with respect to said otherr part, a fluid pump iluidly communicableY withA said motor, the pressure effectivecross-sectional area ofl said pump being substantially less than, that of said motor, and means connected to said pump and operable. by manipulation of said running-in,v string for; generating a fluid pressureinsaid pump and motori,

4. A well tool adapted to belowered in a Well bore. on. a running-in string, including a valve seat,t a valve head engageable with *said seat,

afluid motor engageablezwithsaid head to move of' saidA motor;

5. A well tool adapted to be lowered in a well bore on a running-in string, including a tubular member to be disposed inthe well bore and .hav-

.ing a valve seat, a valve head engageable with said seat, aJiluid motor engageable with said .head to move the same relative to said seat, and `a. uidvpump fluidly communicable lwith said fomotor, the pressure effective cross-sectional area of said pump being substantially less than that of said motor, and means connected to said pump and operable by manipulation of said running-in string for generating a fluid pressure in said pump and motor. e

6. A well tool adapted to be lowered ina well casing" on a'running-in string, including relatively movable parts cooperable with each other to' perform a function in said well casing, a uid motor engageable with one of said parts to move the same, a' uid pump fluidly communicable with said motor and operablev by manipulation of said running-in string,y said v pump comprising a( hollow cylinder element vvand Ia,pistonuelement relatively reciprocable in said cylindernelement, and means connected to'one of said elements and engageable withthe wall of the well casing to resist movement of said one of said elements therewithin, thev pressure eiective cross-sectional area of said pump being substantially less than that of said motor.

'7. A well tool adapted to be lowered in a well casing on a. running-in string, including relatively movable parts cooperable with each other :,f

to perform a function in said well casing, a uid motor engageable with one of said parts to move the same, a fluid pump fluidly communicable with said motor and operable by manipulation of said running-in string, said pump comprising a hollow cylinder and a piston relatively reciprocable in said cylinder, and means connected to said piston and frictionally engageable with the wall of said casing to resist movement of said piston therewithin, the pressure effective cross-sectional area of said pump being substantially less than that of said motor.

8. A well tool adapted to be lowered in a well casing on a running-in string, including a valve seat, a valve head engageable with said seat, a uid motor engageable with said head to move the same relative to said seat, a fluid pump uidly communicable with said motor and operable by manipulation of said running-in string, said pump comprising a hollow cylinder element and a piston element relatively reciprocable in said cylinder element, and meansy connected yto one of said elements and frictionally engageable with the wall of the well casing to resist movement of said one of said elements therewithin, the pressure effective cross-sectional area of said pump being substantially less than that of said motor.

9. A well tool adapted to be lowered in a well casing on a running-in string, a valve seat, a valve head engageable with said seat, a fluid motor engageable with said head to move the same relative to said seat, a fluid Dump fluidly communicable with said motor and operable by manipulation of said running-in string, said pump comprising a hollow cylinder and a piston relatively reciprocable in said cylinder, and means connected to said piston and frictionally engageable with the wall of said casing to resist movement of said piston therewithin, the pressure effective cross-sectional,v area of said pump o being substantially less than that. of Ysaid motor.

l10. Awelltool adapted to be lowered in a well casing on a ,running-in string, including a'well packer vbody'having an outlet, packing means --around said bodyengageable with said casing, valve means connected to said body for controlling low of liuid through said outlet, a uld motor'operatively'connected to said valve means for operating said valve means, a fluid pump fluidly ycommunicable with said motor and operable by manipulation of said running-in string, said pump comprising a hollow cylinder element and a piston element relatively reciprocable in said cylinder.` element, and means connected to one of said elements and frictionally engageable with the wall of said casing to resist movement of said one of said elements therewithin, the pressure eiective cross-sectional area of said pump being substantially less than that of said motor.v f v v' '1l'. A well tool'adapted to be lowered in a well casing ona running-in string, including a well packer body having spaced packing means therearound engageable with said casing, said lbody having an outlet between said packing means, valve means connected to said body below said outlet for controlling flow of fluid through said outlet, a iiuid motor operatively connected to said valve means for operating said valve means, a fluid pump fluidly communicable with said motor and operable by manipulation of said running-in string, said pump comprising a hollow cylinder and a piston relatively reciprocabie in said cylinder, and means connectedv lto said piston and frictionally engageable with the wall of said casing to resist movement of said piston therewithin.

12. A well tool adapted to be lowered in a well casing onl a running-in string, including a well packer body having spaced packing -means therearound engageable with said casing, said body having an outlet between said packing means, a valve housing connected to said body and having a valve seat therein communicable with said outlet, a valve head engageable with said seat, a fluid motor having means engageable with said head to move the same relative to said seat, a uid pump iiuidly communicable with said motor and operable by manipulation of said running-in string, said pump comprising a hollow cylinder and a piston relatively reciprocable in said cylinder, and means connected to said piston and frictionally engageable with the wall of said casing to resist movement of said piston therewithin, the pressure effective cross-sectional area e of said piston being substantially less than that of said motor.

13. A well tool adapted lto be lowered in a well bore on a running-in string,` including relatively `the same, a fluid pump'fluidly communicable V'casing on a running-in string, including relatively movable parts cooperablewith each other to perform a function in said well casing, a rst hollow cylinder connected to one of said parts, a rst piston relatively reciprocable 'in said -iirst cylinder and connected to the other of said 'parts, a second hollow cylinder secured to said first cylinder and communicable therewith, va second piston relatively reciprocable in said second cylinder, means secured to said second'piston and engageable with the wall of said Well casing to resist movement of said second piston therevwithinI the cross-sectional area of said second cylinder being substantially less than the cross- Sectional area of said lirst cylinder.

15. A well tool adapted to be lowered in va well casing on a running-in string, including 4a valve seat, Aa valve head'engageable with said seat, a first hollow cylinder connected to said valve seat,

a first piston relatively reciprocable in Vsaid rst cylinder and connected to said valve head, a second hollow cylinder secured to said rst cylinder and communicable therewith, a second 'piston relatively reciprocable in said second cylinder, means secured to said second piston Vand engageable with the wall of said well casing Ato lresist movement of said second piston therewithin, the Vcross-sectional area of said second cylinder beingsubstantially less than the cross- Vsectional area of said first cylinder.

l16. A w11too1 adaptedto be ioweredina wen casing on a running-in string, including avvalveA seat, a valve head engageable with said seat, a

rst hollow cylinder connected `to said -valve seat,Y

a first piston relatively reciprocable in saidrst cylinder and connected to said valve head, -a second hollow 'cylinder disposed below andsecured to said iirs't 'cylinder and'V communicable therewith, a second 'piston relatively reciproca'ble in 'said second cylinder, means secured Ato said second piston land engageable Vwith the wall-'of rsaidwell casing to'resist 'movement of said M-sec'- ond piston therewithin, the cross-sectionalarea of said second 'cylinder vbeing substantially "less 'than the cross-sectional area of said i-lrstjcylinder.

THOMAS M. RAGAN.

References 'citedV in the nie of Yth-ispareut

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