US3126965A - Valve for well pipe - Google Patents

Description

United States Patent Olice 3,126,965 VALVE FOR WELL PIPE William C. Lindsey, Houston, Tex., assigner, by mesne assignments, to .ersey iiroductiou Research Company, Tuisa, Ghia., a corporation ot Delaware Filed Dec. 9, 196i?, Ser. No. 74,@35 1 Claim. (Cl. 16d-63) The present invention concerns a hydraulically operable circulating and tubing drain valve and its method of use.

Conventional insert subsurface hydraulic pumps used in wells are run in the wells on tubing strings which are used to conduct power or operating fluid to the engine or power parts of the pump assemblies. A disadvantageous feature of this operation is that thread dope, scale, and other materials capable of fouling the engine parts remain in the power tubing string after the pump assembly has been landed and is otherwise ready to begin operation. Therefore, it is desirable to remove these unwanted materials from the power tubing string prior to initiation of pumping operations, and the present invention is directed to this end.

Briefly, the apparatus of the invention includes a nipple provided with fluid circulation ports and connected in the power tubing string adjacent to the subsurface hydraulic pump assembly. The nipple also is provided with an inner shoulder below the ports, which forms a smaller nipple inner diameter below the shoulder and which serves as a stop for a mandrel which is lowerable into and removable from the nipple. The mandrel is provided with a shoulder which forms a smaller mandrel outside diameter below the shoulder and which engages the nipple shoulder. Upper and lower sealing means arranged on the outer surfaces of the mandrel above and below the mandrel shoulder, respectively, seal oif the spaces between the mandrel and nipple above and below the nipple ports, respectively. Thus, the upper sealing means exposes a greater area to lluid pressure within and outside of the power tubing string than does the lower sealing means. The mandrel also has a shing neck at the upper end thereof designed to engage a retrieving tool used to remove the mandrel from the tubing string.

Briefly, the method of the invention includes the steps of running on a tubing string and landing in a well pipe an insert-type subsurface pump assembly, the tubing string being used to conduct power iluid to the pump assembly during pumping operations; circulating duid down the annulus between the tubing string and the well pipe, through circulating ports located in the tubing string above and adjacent to the pump assembly and up the tubing string to ilush out and remove unwanted materials remaining in the tubing string following landing of the pump assembly in the well pipe; and then pumping or otherwise moving a hydraulically removable valve device downwardly through the tubing string and seating it adjacent the circulating ports to prevent fluid ow therethrough. Additionally, the method includes removing the valve device from the tubing string by pumping or otherwise moving a retrieving tool down the tubing string until it latches onto the valve device and then circulating uid down the annulus between the well pipe and the tubing string and through the circulating ports to unseat the valve device and pump it and the fishing tool upwardly through the tubing string to the earths surface. Once the valve device has been removed from the tubing string, the circulating ports serve as drainage ports when the tubing string and pump assembly are pulled from the well.

Thus, primary objects of the invention include providing a hydraulically operable circulating and tubing drain Valve for use with insert-type subsurface hydraulic pumps 3,126,965 Patented Mar. 3l, 1964 that is inexpensive to construct and operate, does not require manipulation of the tubing string to open and close it, and that can function as a tubing drainage means during pulling operations.

The above and other objects and advantages of the invention will be apparent from the following more detailed description thereof given in conjunction with the drawings wherein:

FIG. l is a cross-sectional view of a well bore showing a pump assembly, a power fluid tubing, and a circulating Valve arranged in the power fluid tubing positioned in the well bore;

FIG. 2 is a vertical, partly-sectional view showing the circulating valve of FIG. 1 in greater detail; and

FIG. 3 is a vertical, partly-sectional view showing one element of the circulating valve being removed from the power tubing string by means of a retrieving tool.

Referring to the drawings in greater detail, in FIG. 1 is shown a well pipe 11B penetrating a subsurface oilcontaining formation 11 perforated as at 12. A conventional insert-type subsurfacehydraulic pump assembly 13 is shown landed in apump seating unit 14 positioned in well pipe 1d. The upper end ofpump assembly 13 is connected to the lower end of atubing string 9 used to conduct power iiuid from a surface source, not shown, to the engine orpower end 19 ofpump assembly 13.Power tubing string 9 liuidly communicates with aconduit 16, which in turn uidly communicates with the power uid source through well-head 15. Asurface conduit 13 used to conduct mixed production fluids and spent power or operating fiuids iluidly communicates with the annulus A between tubing string andpipe string 10 throughwellhead 15. A circulatingvalve 17 is arranged in powerfluid tubing string 9adjacent pump assembly 13. Ports 2d adjacent thepower end 19 ofpump assembly 13 exhaust spent power duid intoannulus A. Ports 22 and 23 positioned on each end of thepump end 21 ofpump assembly 13 exhaust pumped production fluids into annulus A.

In FIGS. l and 2 the paths of the uids are illustrated by arrows. The light arrows designate the paths of the power fluid flow, rand the dark arrows designate the paths of the production fluid flow. In FlG. 3 the dark arrows represent the path of flow of the duid used to unseat and remove fromtubing string 9 an element ofvalve 17. The elements ofvalve 17 are seen more clearly in FIG. 2. The valve includes a nipple 3 connected in tubing string kil and provided withfluid circulation ports 24, which fluidly communicate the interior and exterior thereof. A no-go shoulder 25 is formed on the inner surface ofnipple 8 belowcirculation ports 24. This shoulder forms on the inner surface ofnipple 8 an upper portion of diameter D1 and a 4lower portion of smaller diameter D2 (see FIG. 3). A mandrel 2e seated in nipple S is provided 'with a shoulder Z formed on the outer surface thereof. This shoulder forms upper and lower, larger and smaller, respectively, outside diameters onmandrel 26. Anupper packoi 29* is arranged on the larger diameter portion ofmandrel 26 to seal off the space betweennipple 8 andmandrel 26 above circulatingports 24 whenshoulder 28 rests onshoulder 25. A lower packoff 3h is arranged on the smaller diameter portion ofmandrel 26 to seal oft the space between nipple S andmandrel 26 belowshoulder 25 whenshoulder 28 rests onshoulder 25. An insideiishing neck 27 is formed on the upper end ofmandrel 26. Mandrel 26 is positioned withinnipple 8, as illustrated in FlG. 2, during pumping operations. Thus, power uid designated by the light arrows is pumped downtubing string 9 and through the opening inmandrel 26 to pumpassembly 13.

FIG. 3 shows mandrel 26 connected toaretrieving tool 31 and both being pumped upwardly through tubing 3string 9. The retrieving tool includes alishing neck 32 adapted to engage a wire line lishing tool; aswab cup 33 formed to prevent upward fluid liow past the retrieving tool; amandrel 34 having an enlarged knobbedlower end 37; and acylindrical member 7 slidably arranged onmandrel 34 and provided with lingers orcollets 35 having latchingdogs 6 positioned on the ends thereof for engaging the inwardly projecting lugs offishing neck 27 and for locking retrievingtool 31 in fishing neck '27 when mandrel 34 is moved upwardly relative tocylindrical member 7, and the surfaces ofknobbed end 37 and dogs r6 engage as at '38. In operation, afterpump assembly 13 in run inpipe string 10 ontubing string 9 in whichnipple 8 is connected and landed inseating unit 14 and the proper wellhead connections are made up, fluid is cir culated throughconduit 18 down annulus A throughcirculation ports 24 and upwardly throughnipple 8 andtubing string 9 land throughconduit 16 to liush out and remove materials such as sand, scale, thread dope, etc., that may have remained intubing string 9 following running and landing of pump assembly P13. After these materials have been removed by the circulating fluids, circulation of fluids in this manner is halted, andmandrel 26 is dropped intotubing string 9 and either circulated downwardly therethrough by circulating fluids downtubing string 9 and throughcirculation ports 24 and up annulus A or allowed to fall into position innipple 8. Downward movement of mandrel 26 is arrested when no-goshoulder 25 engagesshoulder 28. This position ofmandrel 26 is shown in FIG. 2, and it is the position of the mandrel during pumping operations. To openatepump assembly 13, power fluid is pumped throughconduit 16,wellhead 15,tubing string 9, andmandrel 26 to thepower end 19 `ofpump assembly 13. The power fluid is discharged frompump assembly 13 throughports 20 into annulus A, where it mixes with production lluids from formation 11, which enterpump end 21 ofpump assembly 13 and are discharged therefrom into annulus A throughports 22 and I23. The mixed spent power lluid and production liuids [are pumped up annulus A through wellhead intoconduit 18. In this operation, iiuid pressure withintubing string 9 is greater than the fluid pressure in annulus A, and this differential pressure acts on the differential area `formed by diameters D1 and D2 ofpackoffs 29 and 30, respectively, to holdmandrel 26 in place innipple 8.

When it is desired to removemandrel 26 fromtubing string 9, retrievingtool 31 is pumped downtubing string 9 until theknobbed end 37 ofmandrel 34 anddogs 6 ofcollets 35 are positioned insidefishing neck 27. Then, as seen in FIG. 3, an external pressure is applied in annulus A by pumping iiuid throughconduit 18 andwellhead 15 into annulus A, which acts on the differential areas ofseals 29 and 30 and movesmandrel 26 upwardly to open circulatingports 24. Once these ports have opened,mandrel 26 and retrievingtool 31 are reverse circulated fromtubing string 9 by the liuid pressure acting on the under side `ofswab cup 33.Fishing neck 32 is provided in the event diliiculties are encountered in removingmandrel 26 and retrievingtool 31 hydraulically, and it is found necessary to use ywire line tools to effect the removal thereof. Aftermandrel 26 has been removed fromnipple 8 andtubing string 9,pump assembly 13 may be removed frompipe string 10 by pulling uptubing string 9. In this operation,circulation ports 24 act as drainage ports for fluids contained intubing string 9.

Having fully described the elements, objects, and operation of my invention, I claim:

Apparatus for use in pumping fluids from a well comprising:

an hydraulically operated subsurface pump arranged in said well;

a tubing string connected at its lower end to said pump and at its upper end to a source `of power fluid for supplying power fluid to said pump;

a circulating nipple vhaving circulation ports and connected in said tubing string :above and adjacent said pump, said nipple also having an inner annular shoulder below said ports providing upper and lower bore portions in said nipple of, respectively, larger and smaller diameters;

a hollow tubular mandrel removably .arranged within said nipple and adapted to permit power iluid to circulate therethrough, said mandrel having an outer annular shoulder thereon intermediate the length thereof providing on said mandrel upper and lower portions, of respectively, larger and smaller diameters, and adapted to seat on said nipple inner shoulders; and

upper and lower packers arranged, respectively, on the larger and smaller diameter portions of said mandrel adapted to seal off the space between said nipple and said mandrel above and below, respectively, said nipple ports when said mandrel outer shoulder is seated on said nipple inner shoulder.

References Cited in the lile of this patent UNITED STATES PATENTS

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