US3108467A - Retrievable casing tester - Google Patents

Description

Oct. 29, 1963 e. E. LAYTON RETRIEVABLE CASING TESTER 2 Sheets-Sheet 1 Filed Jan. 25, 1960 INVENTOR. GERALD E. LAYTO/V ATTORNEY Oct. 29, 1963 5, LAYTON 3,108,467

RETRIEVABLE' CASING TESTER Filed Jan. 25, 1960 2 Sheets-Sheet 2 9 29 3B 25 24 I 26 2s I l3 3 so l4 l6 I? 3 F /'g. 5

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INVENTOR. GERALD E. LAYTO/V I Fig. 4

ATTORNEY United States Patent Ofi ice hill-8A6? Patented Oct. 29, 1963 3,108,467 RETRIEVABLE CASING TESTER Gerald E. Layton, 3668 Monaco Parkway, Denver, Colo.

Filed Jan. 25, 1960, Ser. No. 4,448 4 Claims. (43]. 73-405) In functional analogy with, as a development from, and an improvement in certain respects over the disclosures of my application for Letters Patent of the United States filed on June 15, 1959, Serial No. 820,206, this invention relates to equipment useful in the conditioning of deep earth bores, such as oil wells, and the like, for extension and production, and more particularly to an equipment unit repetitiously applicable to facilitate test for imporosity of easing lengths as appropriate during placement of the easing for conventional operation within a bore, and has as an object to provide a novel and improved such unit selectively applicable to and retrievable from sealing coaction with the lower end interior of a casing length entered to ultimate use position at any depth within an earth bore.

A further object of the invention is to provide a novel and improved unit selectively applicable to and retrievable from sealing coaction with the lower end interior of a casing length Within an earth bore in reaction to \means and influences conventionally complementary to place ment of the casing.

A further object of the invention is to provide a novel and improved repetitiously-employable, retrievable unit selectively applicable to sealing coaction with the lower end interior of a casing length within an earth bore in reaction to fluid pressures regulably applied to the casing interior thereabove.

A further object of the invention is to provide a novel and improved repetitiously-employable unit selectively applicable to sealing coaction with the lower end interior of a casing length within an earth bore in reaction to fluid pressures regulably applied to the casing interior and retrievable upon abatement of such pressure through the sole agency of a line conventionally complementary to casing placement operations.

A further object of the invention is to provide a novel and improved casing testing adjunct selectively applicable to and retrievable from sealing coaction with the lower end interior of a casing length within an earth bore that is immediately recoverable after each instance of practical use in condition for reuse to leave unaltered the casing zone thereby engaged.

A further object of the invention is to provide a novel and improved casing testing adjunct selectively applicable to and retrievable from sealing coaction with the lower end interior of a casing length within an earth bore that is compact in a light-weight unitary assembly amenable to controlled adjustment longitudinally of and operatively within earth bore casings in attachment to a line conventionally complementary to casing placement operations.

A further object of the invention is to provide a novel and improved casing testing adjunct selectively applicable to and retrievable from sealing coaction with the lower end interior of a casing length within an earth bore that is expedient of adaptation at the side of use for operative coaction with casings and casing components of diverse size particularity. I

A further object of the invention is to provide a novel and improved casing testing adjunct selectively applicable to and retrievable from sealing coaction with the lower end interior of a casing length within an earth 'bore that is expedient of adaptation at the site of use for operative coaction with casings and casing components in diverse adjustments to differing field conditions.

A further object of the invention is to provide a novel and improved construction and operative correlation of elements constituting a testing adjunct selectively applicable to and retrievable from sealing coaction with the lower end interior of a casing length within an earth bore.

A further object of the invention is to provide a novel and improved retrievable casing tester that is simple and inexpensive of production from available materials in an extensive range of desired sizes, that is durable throughout a long life of repetitious use, that is effectively operable in automatic reaction to influences regulably applied to and through the end of the casing accessible at ground level, and that is positive and efficient in attainment of the ends for which designed.

With the foregoing and other objects in View, my invention consists in the construction, arrangement, and operative combination of elements as hereinafter set forth, pointed out in my claims, and illustrated by the accompanying drawings, in which- FIGURE 1 is a vertical section longitudinally through the lower end portion of a casing length positioned for placement Within an earth bore with a typical embodiment of the invention shown in side elevation as associated with the casing for sealing coaction therewith, an intermediate length portion of the view not essential to an understanding of the invention being broken away to conserve space.

FIGURE 2 is a longitudinal section, on a relativelyenlarged scale, axially through the lower portion of the embodiment according to and as positioned in the showing of FIGURE 1.

FIGURE 3 is a longitudinal section, on the same scale as FIGURE 2, axially through the upper portion of the embodiment according to and as positioned in the showing of FIGURE 1, an intermediate length portion of the continuous member comprised in the view being broken away to conserve space.

FIGURE 4 is a longitudinal section similar to FIGURE 2. showing telescopically-associated elements thereof in an alternative condition of operative interrelation thereby assumed during transit of the assembly to and from sealing coaction with conventional casing components.

FIGURE 5 is a fragmentary side elevation, partially in section, of the lower end of the organization according to FIGURES l, 2 and 4 as size-adapted within the contemplation of the invention.

FIGURE 6 is a fragmentary side elevation, partially in section, of the lower portion of the organization according to FIGURES 1, 2 and 4 as alternatively coupled within the contemplation of the invention.

Deep earth bores developed for the production of water, petroleum oils, gases, and the like, are commonly conditioned for production, and for extension in depth, through the provision of bore linings in the form of continuous lengths of rigid, tubular, usually-metallic casing assembled through the intercoupling of separate, like sections at the mouth of the bore as the completed length is lowered therethrou gh. As conditioned for casing, the bore confines, or may be charged with, a column of liquid which is availed of to in an important measure counteract the progressively-increasing weight of the casing length descending therein, for which purpose the otherwise open, lower end of the casing length is obstructed by a tubular plug, termed a float collar, coaxially and fixedly associated in diverse conventional structural particularity with the end of the casing first inserted in the bore to restrict, but not to close, the path of liquid access to the casing interior, which plug, or float collar, is subsequently drilled out of the casing upon completion of the desired casing placement. It being customary to finally cement the placed casing in its use posit-ion within the bore, and it being material to ultimate efiicient production through the casing that the latter be free from leakage of confined flow therethrough, it is approved practice to pressure-test the casing length [for imporosity after placement and before cementing thereof relative to the bore, in expeditious, economical, and practical furtherance whereof the instant invention is directed to the provision of an adjunctive unit retrievably coactab'le with the float collar of a placed casing length to function as an abutment closing the lower end of the length in reaction to pressures applied interiorly \of the casing therea-bove for test of casing integrity.

'Iypifying the use environment of the invention, the lower end portion of a continuous length of conventional tubular Casing is indicated by the numeral and shown in FIGURE 1 of the drawings as loosely engaged at any appropriate depth within an earth bore for fixed emplacement relative thereto, and as furnished with a conventional, tubular, cementitious float collar 11, carried as is customary in a coupling 12 threadedly connectible with and as an extension of said casing length, partially obstructing its otherwise fully open lower end to represent a flat, annular shoulder transversely of and opposed to the interior of said length 10.

Selectively and retrievably operable to realization of its purposes within the environment typified by the casing portion 10, float collar 11, and coupling 12, the improvement of the invention is an axially-elongated, unitary assembly of the coaxial, relatively-reciprocable cylindrical elements hereinafter specified having a maximum diameter less than the interior diameter of the casing 10 adapting it for free reciprocation within the casing.

In accordance with and to give effect to the principles of the invention, the lower end of the retrievable unit assembly is constituted as a rigid, tubular member l3 freely and loosely reciprocable interiorly of the casing 10 in a length desirably several times its exterior diameter and a tubular nose plug 14 detachably coaxial in threaded engagement with the lower end of said member. In a maximum diameter exceeding that of the open throat through the float collar 11 wherewith it is designed to coact, the nose plug 14 surrounds an axial bore slightly smaller than that of the member 13, is exteriorly reduced and externally threaded at one end to the form of a shouldered stem engageable in and with the internal threads of the lower end of said member, mounts a sealing ring 15 at the junction of its threaded stem with the plug body position to compress against the adjacent end of the member 13 and close the thread joint when the plug is fully seated in the member thereby, is exteriorly reduced and tapered at its other end to the form of a shouldered nose extremity 16 sized to enter and substantially fill the open throat through the float collar 11 of an associated casing, and is circumferentially rabbeted at the junction of said extremity 15 with the plug body for retentive accommodation of a sealing ring 17 thereby disposed to close and compress against the opposed peripheral corner of the float collar throat receptive of the plug extremity 16. At its end remote from the plug 14 the member 13 is interiorly shouldered about a slightly-reduced bore wherein a tubular sleeve 18 is slidably and coaxially accommodated telescopic, reciprocable association with said member through a range limited in one direction by an annular shoulder exteriorly about the end of said sleeve opposed to the plug 14 adapted for engagement against the interior shoulder of the member 13 for determination of maximum sleeve extension from the member, and limited in the other direction by a washer 19 about and inwardly adjacent the sleeve end exterior to the member detachably retained thereon between a snap ring 20 groove-seated in the sleeve at the side of the was-her remote from the member 13 and a sealing ring 21 at the side of said washer opposed to said member in position to at times close the slide joint between said sleeve and the interiorly-shouldered endof the member. The tubular wall of the sleeve 18 is intersected by angularly-spaced slots 22 longitudinally thereof in a length-correlation therewith such as to fully expose the slots when the sleeve is at the limit of its extension outwardly from the member 13, as in FIGURE 4, and to wholly confine said slots within said member when the sleeve is at the limit of its retraction inwardly thereof, as in FIGURE 2.

Telescopically, coaxially, and reciprocably associated with the sleeve '18 in the same manner as the latter is associated with the member '13, a rigid tube 23 slidably accommodated through a slightly-reduced bore at the interiorlyshouldered end of said sleeve exterior to said member is formed with an annular shoulder exteriorly of its end directed toward the plug 14 adapted to at times engage the interior shoulder of the sleeve as a stop limiting extension of said tube from the sleeve in a direction away from said plug and is provided with a washer 24, snap ring 25, and sealing ring 26, functionally and structurally identical, save as to size, with the washer and ring assembly 1920-21 of the sleeve 18, operable at times to limit retraction of the tube 23 within the sleeve and concomitantly close the slide joint there-between. The tube 23 is formed with singularly-spaced, longitudinal slots 27 in a length correlation such as to fully expose the same when the tube is at the limit of its extension outwardly from the sleeve 18, as in FIGURE 4, and to wholly confine said slots within said sleeve when the tube is at the limit of its retraction inwardly of the sleeve, as in FIGURE 2. The tube 23 is formed with a shouldered, annular, interior restriction 28 adapted to function as a valve seat at the zone thereof embraced by the washer 24 and with holes 259 in an angular spacing radially through its wall outwardly adjacent said restriction in a direction away from the sleeve 18, beyond which holes said tube continues in substantial elongation to an externally-threaded, free end termination.

In a preferred organization appropriate for intended coaction with deep bore casings, the outward termination of the tube 23 threadedly engages within an end of a coaxial tubular coupling 30 thereto secured by a clamp nut 31 and a link 32 slidably coaxial with said coupling by virtue of a lost-motion connection thereto, such as a pin 33 fixed diametrically of the coupling end remote from the tube 23 through and to work in a diametric slot 34 longitudinally of the link, coaxially and detachably mounts for actuation therewith a cylindrical stem 35 extending from the end thereof adjacent the tube 23 and adapted for telescopic reception and reciprocation within the latter. For purposes of expedient separable, operative interassociation, the end of the link 32 mounting the stem 35 may be formed with a diametric and axially-opening keyway slot adapted to laterally receive and loosely accommodate a necked, terminal head 36 on the coacting end of the stem, and the end of said stem 35 remote from the link 32 is shouldered about a coaxial terminal finger 37 sized to freely enter the restriction 23 of the tube 23 through a sealing ring 38 compressible at times between the opposed shoulders of said stem and restriction. The lost-motion travel of the link 32 relative to the coupling 30 and the length of the stem 35 extension axially from said link are proportioned to enter the stem finger 37 fully within the restriction 28 of the tube 23 and to compressive engagement of its adjacent shoulder with the sealing ring 38 when the link 32 is at the limit of its travel inwardly of the coupling 30, as in FIGURE 2, and to retract said stem and its finger 37 away from said restriction and into clearing relation with the holes 29 of the tube 23 when said link is at the limit of its travel outwardly with respect to the coupling, as in FIGURE 4.

The end of the link 32 remote from the coupling 30 is externally threaded for connection to and within one end of an elongated, relatively-massive bar 39 adapted to function, when appropriate, as a jar in a well-known manner accommodated by the lost-motion connection of the link to the coupling 30, which bar is expediently provided with chordal flats 40 to facilitate its threaded interassenrbly with other elements of the organization and is secured in operative association with the link by a clamp nut 41. The end of the bar 39 remote from the link 32 is formed as an externally-threaded, coaxial stud 42 engageable within and to mount a coaxial thimble 43 attached at, or through, its closed end to a flexible manipulating line 44 customarily available at the site of bore casing operations to effect transit of equipment and facilities interiorly of the bore; said thimble desirably presenting exterior, angularly-related surfaces for engagement by a tool applicable to effect relative rotation of the thimble with respect to the stud 42 and bar 39'. To guide and operatively center the bar 39 interiorly of the casing 10, it is practical to provide on and exteriorly about and near the upper end of said bar a radially-resilient basket yieldably adaptable to sliding coaction with casing of diifering sizes, and such a basket is typified as consisting of like collars 45 slidably and rotatably embracing the bar 39 in a variable spacing axially of the bar determined by a plurality of angularly-spaced, convexly-bowed spring strips 46 fixedly connecting therebetween, which basket is retained in self-adjusting relation with the bar between snap rings 47 groove-seated circumferentially of the bar in a spacing axially thereof exceeding the length of the unstressed basket.

Practical use and operation of the organization illustrated and thus far described should be reasonably apparent from the foregoing explanation of structure. In an integrated assembly of suitable size provided with a nose extremity 16 engageable through the open throat of the float collar 11 known to be associated with the casing 10, the improvement of the invention is lowered through the casing in suspension from the line 44 with the telescopically-associated elements thereof at the gravity-induced limit of their relative extension in the relationship represented by FIGURE 4. Extended as shown in said latter view during the lowering operation, a passage for uprise of casing fluid charge is open through the bore of the plug 14, the interior of the member 13, the bore of the sleeve 18 and radially therefrom through the slots 22, the bore of the tube 23 and radially therefrom through the slots 27, the throat of the restriction 28 and radially of the tube 23 thereabove through the holes 29, whereby unimpeded descent of the assembly through the casing is assured; any lodgemcnt of the assembly during descent through the casing being readily relieved by linear agitations of the line to consequent actuation of the jar typified by the bar 39 and its lost-motion connection. Approach of the plug 14 to the float collar 11 effects engagement of the nose extremity 16 within the throat of the float collar and seating of the ring 17 in sealing coaction with the upper rim of the throat, whereafter, under the influence of their inherent weights and consequent loadings, the telescopically-associated elements of the assembly continue to descend to the limit of their relative retraction and assume the positions represented by FIG- URE 2 wherein fluid passage from beneath the float collar and through the assembly to the interior of the casing is interrupted and passage of fluid in the opposite direction from the casing interior and to the zone beneath the float collar is inhibited by the seals closing all of the slide joints of the unit. With the assembly seated on the float collar, compacted, and sealed as shown and described, fluid is introduced under pressure to the interior of the casing thereabove to a degree and for a time appropriate to determine imporosity of the casing as reflected by variations of sustained pressure, the reaction of the fluid so introduced under pressure on the unit resisting its escape through the float collar being but to augment the sealed coaction of the unit elements. Upon release of the pressure interiorly of the casing, tension applied to the line 44, supplemented it needful by jar effect developed through the bar 39, first acts to extend the telescopically-associated elements of the unit for consequent opening of a flow passage therethrough as above set forth and then serves to lift the unit lfIOIIl the casing with negligible resistance by the casing liquid charge to ultimate recovery of the unit in condition for immediate reuse.

The detachable interassociation of the plug 14 and member 13 qualifies a given structural embodiment of the invention for adaptation to use in and with casings of diverse diametric sizes accommodative of unit transit therein and for operative coaction with float collars of different throat sizes through simple selection and attachment to the member of a plug of appropriate diameter and nose extremity size. It is eminently practical to provide a plurality of plugs 14 respectively formed with a nose extremity 16 sized in shouldered relation with the plug body to enter and fill a float collar throat of known conventional particularity, so that, as typified by FIGURE 5, a plug 14 proportioned as represented in FIGURES 1, 2 and 4 expediently may be replaced by a functionallyidentical substitute plug 14' having an externally-threaded stem connectible to the lower end of the member 13 and provided with the sealing ring 15 which distinguishes from the plug 14 only in an operatively-correlated variation of body 14', nose extremity 16', and sealing ring 17 diameters. With a plug 14' terminating the unit in a diametric size exceeding that of the associated member 13 it is desirable that the end of said member remote from the plug be radially enlarged for unit-guiding coaction with the casing interior, for which purpose an annular collar 48 adapted to slidably embrace said member may be engaged therewith and retained adjacent the member end remote from the plug between snap rings 49 received in spaced grooves '50 circumierentially of the member exterior.

Further adaptation of the unit to effectuate desired operations in certain of varying situations and under difiering field conditions is accommodated by forming the externally-threaded end portions of the tube 23, link 32, and bar 39, and the thread components coactable therewith, to like diametric size and thread pitch, whereby to provide that the thimble 43 may be directly connected, at option, to either the link 32 or tube 23 with consequent elimination of the elements and features hereinabove described as normally therebetween. As is fully obvious, connection of the thimble 43 directly to the outward, threaded end of the link 32 reduces the length and weight of the unit assembly through elimination of the bar 39 with retention of all fiunctional properties and relationships of the improvement, including the lostm-otion linkage operable under reduced mass with jarring effect, as previously discussed. Alternative connection of the thimble 43 directly to the outward, threaded end of the tube 23, exemplified by FIGURE 6, yet further reduces the length and weight -of the resulting assembly through elimination, in addition to the bar 39, of the coupling 30, link 32, and stem 35, with consequent removal of the lost-motion linkage and the functions peculiar thereto, it being requisite to practical use of the assembly as so modified that, in the absence of the stem 35 and its finger 37 sealably coactable with the restriction 28, the holes 29 of the tube 23 be plugged, or otherwise closed, as indicated, to fully stop any passage for fluid flow through the unit in its retracted state, other than which the operation and functional applicability of the arrangement according to FIGURE 6 are the same as those of the embodiment first described.

Since changes, variations, and modifications in the form, construction, and arrangement of the elements shown and described may be had without departing from the spirit of my invention, I wish to be understood as being limited solely by the scope of the appended claims, rather than by any details of the illustrative showing and foregoing description.

I claim as my invention:

1. A retrievable casing closing means adapted to freely descend through a tubular casing having fluid therein, for cooperation with a float collar disposed within said casing at the location where said casing is to be closed 7 and extending inwardly from the casing Walls, said closing means comprising:

(a) a telescopically associated extensible and retract able assembly of at least two cylindrical elements loosely receivable within the casing for free reciprocation longitudinally thereof;

(b) each of said elements having a bore extending longitudinally therethrough, the bores in said elements being coaxial and extending between an open end and an opposite closed end of said assembly;

() means at the closed end of said assembly connectable with a line manipulatable to regulate assembly travel relative to the casing;

(d) means at the open end of the assembly adapted for sealing coaction with the float collar at the limit of assembly travel downwardly through the casing, said means having a bore extending therethrough coaxial with the first mentioned bores;

(e) at least one of said cylindrical elements having a plurality of radially extending openings therein communicating said bores through said one cylindrical element directly with the exterior of said assembly when extended whereby said assembly can freely descend, as extended, through the casing with the fluid therein passing substantially freely through said bores and said openings;

(7) said one element being reciprocally receivable within the bore of another in retracted position of said assembly;

(g) said one element having spaced shoulder and abutment means thereon to alternatively limit extension and retraction of said one element with respect to said another element, said shoulder means engaging said another element interiorly thereof, and said abutment means engaging said another element exteriorly thereof;

(It) said abutment means comprising a laterally projecting member and a compressible sealing means for fluid sealing said elements with one another in retracted position of said assembly, said sealing means being disposed in underlying abutting relation to said member for engagement exteriorly with said another element;

(i) said openings extending over a substantial longtudinal portion of said one element but terminating within the area of said one element reciprocally receivable within said another element in retracted position of said assembly, whereby as retracted, said assembly will not pass fluid therethrough;

( said member providing a surface against which fluid under pressure can act to press said assembly, as retracted, into sealing engagement with the float collar, and to press said sealing means against said another element.

2. A retrievable casing closing means as defined in claim 1 and further including a third cylindrical element,

said third cylindrical element being loosely receivable within said casing for free reciprocation longitudinally thereof, said third element haivng a bore extending longitudinally therein coaxial with the first mentioned bores, a stem reciprocally slidable in the bore of said third element, said third element having a restriction therein cooperable with said stem to close said bore in said third element, said third element having radial openings therein above said restriction and past which said stem is slidable, connecting means coupling said stem to said means manipulatable to regulate assembly travel for control thereby, said third element being reciprocally receivable within the bore of said one element in retracted position of said assembly; said third element having spaced shoulder and abutment means thereon, to alternatively limit extension and retraction of said third element with respect to said one element; said shoulder means on said third element engaging said one element interiorly thereof, and said abutment means on said third element engaging said one element exteriorly thereof, said abutment means on said third element comprising a laterally projecting member and compressible sealing means for fluid sealing said third element with said one element in retracted position of said assembly, said last mentioned sealing means being disposed in underlying abutting relation to said last mentioned member for engagement exteriorly with said one element; said last mentioned member providing a surface against which fluid under pressure can act to press said last mentioned sealing means against said one element.

3. A retrievable easing closing means as defined in claim 2 wherein said connecting means comprises a socket connected to said stem and a lost-motion connection between said socket and said means manipulatable to regulate assembly travel.

4. A retrievable casing closing means as defined in claim 1 wherein said means adapted for sealing coaction with the collar is a cylindrical plug having a diameter exceeding the interior diameter of the float collar, said plug being detachably connected to said assembly as a lower extension therefrom, said plug being formed with a bore diametrically smaller than the interior diameter of the float collar, said plug having a frusto-conical nose adapted to fully enter the float collar, said plug having a shoulder projecting about and above said nose, said plug carrying sealing means underlying said last-mentioned shoulder for sealing engagement with the throat collar.

References Cited in the file of this patent UNITED STATES PATENTS 2,128,716 Smith Aug. 30, 1938 2,129,216 Johnson Sept. 6, 1938 2,287,319 Miller June 23, 1942 2,868,297 Lamberson Jan. 13, 1959

Claims (1)

1. A RETRIEVABLE CASING CLOSING MEANS ADAPTED TO FREELY DESCEND THROUGH A TUBULAR CASING HAVING FLUID THEREIN, FOR COOPERATION WITH A FLOAT COLLAR DISPOSED WITHIN SAID CASING AT THE LOCATION WHERE SAID CASING IS TO BE CLOSED AND EXTENDING INWARDLY FROM THE CASING WALLS, SAID CLOSING MEANS COMPRISING: (A) A TELESCOPICALLY ASSOCIATED EXTENSIBLE AND RETRACTABLE ASSEMBLY OF AT LEAST TWO CYLINDRICAL ELEMENTS LOOSELY RECEIVABLE WITHIN THE CASING FOR FREE RECIPROCATION LONGITUDINALLY THEREOF; (B) EACH OF SAID ELEMENTS HAVING A BORE EXTENDING LONGITUDINALLY THERETHROUGH, THE BORES IN SAID ELEMENTS BEING COAXIAL AND EXTENDING BETWEEN AN OPEN END AND AN OPPOSITE CLOSED END OF SAID ASSEMBLY; (C) MEANS AT THE CLOSED END OF SAID ASSEMBLY CONNECTABLE WITH A LINE MANIPULATABLE TO REGULATE ASSEMBLY TRAVEL RELATIVE TO THE CASING; (D) MEANS AT THE OPEN END OF THE ASSEMBLY ADAPTED FOR SEALING COACTION WITH THE FLOAT COLLAR AT THE LIMIT OF ASSEMBLY TRAVEL DOWNWARDLY THROUGH THE CASING, SAID MEAN HAVING A BORE EXTENDING THERETHROUGH COAXIAL WITH THE FIRST MENTIONED BORES;

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