|Número de publicación||US2605131 A|
|Tipo de publicación||Concesión|
|Fecha de publicación||29 Jul 1952|
|Fecha de presentación||27 Feb 1948|
|Fecha de prioridad||27 Feb 1948|
|Número de publicación||US 2605131 A, US 2605131A, US-A-2605131, US2605131 A, US2605131A|
|Inventores||Marshall Samuel J E, Wilhoit Lowell M|
|Cesionario original||Otis Eng Co|
|Exportar cita||BiBTeX, EndNote, RefMan|
|Citas de patentes (3), Citada por (19), Clasificaciones (7)|
|Enlaces externos: USPTO, Cesión de USPTO, Espacenet|
July 29, 1952 s. J. E. MARSHALL ET Al. 2605131 RETRIEVING TOOL Filed Feb. 27, 1948 ATTORNEY Patented July 29, 1952 RETRIEVING 'rooL Samuel J. E. Marsh-all and Lowell M. Wilhoit,
Dallas, Tex., assignors to Otis Engineering Corporation, Dallas, Tex., a corporation of Texas Application February 27, 1948, Serial No. 11,366
3 Claims. (Cl. 294-86) This invention relates to new and useful improvements in retrieving tools.
One object of the invention is to provide an improved retrieving tool which may be run into a well iow conductor on a flexible line, such as a steel measuring line, and which is arranged to releasably engagea well device, whereby said retrieving tool may be utilized to remove the well device from the bore of the well conductor.
Another object of the invention is toI provide an improved retrieving tool having supporting means freely engageable with a well device for removing such device from the well, said supporting means being positively held in .engaged position when engaging the well device, whereby possibility of disengagement of the retrieving tool from the well device during the removing operation is reduced. Y
An important object of the invention is to provide an improved retrieving tool wherein the supporting means is positively held in its engaged position, and wherein said supporting means is constructed and arranged to be positively moved to disengaged position upon movement of actuating means relative to said supporting means.
A further object of the invention is to provide an improved retrieving tool ofthe character described, wherein the actuating means which moves the supporting elements to disengaged position is normally held inactive by releasable restraining means and is automatically actuated upon release of the restraining means.
Still another object of the invention is to provide a retrieving tool wherein thek supporting means is normally urged toward engaging position, and wherein the means urging such supporting means to engaging position is rendered inoperative when the actuating means is moved to cause movement of thesup-porting means to disengaged position. A
A particular object of the invention is to provide a retrieving tool of the character described having supporting means freely engageable with a well device for removing such device from the well, and having actuating means movable on the retrieving tool with respect to the supporting means for positively engaging the supporting means to positively move said supporting means to released position, said actuating means being normally restrained against movement.
A still'further object of the invention is to provide an improved tool for retrieving from a well conductor a well device having a mandrel and a gripping mechanism movable on said mandrel, said retrieving tool being adapted to engage the mandrel of the well device whereby force may be applied to said mandrel to release the gripping mechanism from gripping position, said retrieving tool being arranged to engage and supportthe gripping mechanism to permit removal of the well device from the conductor.
Still another object of the invention is to pro--v vide a retrieving tool, of the character described, wherein the supporting element is itself supported, whereby the weight of the well device with which the retrieving tool is engaged is not carried solely by the supporting element.
Another important object of the invention is to provide a retrieving tool, of the character described, wherein the restraining means for normally restraining the actuating means against movement of the supporting element to retracted releasing position includes a frangible element which is fully enclosed within the tool, whereby when said frangible element is fractured the pieces thereof cannot fall into the bore of the well `around the well device to interfere with the removal thereof, said frangible element being adapted to fracture under a predetermined strain to release the actuating means, whereby the actuating means may vact upon the supporting element to positively move said supporting element to retracted disengaged position to release the retrieving tool from the well device.
Still another object of the invention is to provide an improved retaining member for retaining the fractured frangible element pieces within the tool.
Additional objects and advantages of the invention will be readily apparent from a reading of the following description of a device con-V structed in accordance with the invention, and reference to the accompanying drawings thereof, wherein:
Figure l is a view, partly in elevation and partly in section, of aretrieving tool constructed in accordance with the invention, and showing the same being lowered into a well for engaging a well device,
Figure 2 is a view, partly in elevation and. partly in section, of the lower portion of the retrieving tool, showing the retrieving tool moving into supporting engagement with the well device,
Figures 3 and 4 are horizontal cross-sectional views taken on the line 3-3 and 4-4 respectively ofFigure 1, and
Figure 5Y is a view, partly in elevation andv partly in section, of the retrieving tool, showing the supporting means in disengaged or releasing position.
In the drawings, the numeral lll designates an elongate body or core which is substantially cylindrical and which is provided with an upstanding externally screw-threaded pin il at its upper end. The pin is reduced in diameter relative to the external diameter of the core, whereby an upwardly VVfacing annular shoulder l2 is formed at the junction of the body and the pin. The lower end of the core is formed with an eX- ternal annular flange i3, providing an upwardly facing shoulder or seat lli at its upper end.
An elongateV substantially cylindrical sleeve member l5 is Slidably mounted on the core IG, and has the major portion of its bore enlarged as shown at i5 to slide over the flange I3 at the lower end of the core. The upper portion of the bore of the sleeve l5 is slidable on the cylindrical portion of the core. apair of diametrically opposedY longitudinal slots lflwhich terminate short of the lower end of the sleeve i5 and extend upwardly Vsubstantially throughout the lower half or portion of the length of the enlarged bore of the sleeve. Windows or openings IS are formed in the sleeve spaced above and in longitudinal alignment with theV ,slots l'l in said sleeve. sleeve is preferably provided with fluid by-pass ports EilV which are formed in the wall of thev .-V
sleeve between the slots l1.
A pair of elongate supporting elements or dogs 2B are disposed diametrically opposite eachother withinjthe'slots i'l in the sleeve, and are confined at their, upper ends between said sleeve and the lower portion of the core IG.Y Each dog has an upwardly facingV hook or engaging element 2l formed at its lower end portion, and is provided near its upper end with an internal downwardly facing shoulder 22 which is adapted to engage and be supported on theseat or shoulder IG at the upper end of the flange i3 of the core. Above the shoulder 221, the outer surface of each dog is provided with an onset or recess 23 whereby said upper portion of the dog may extend upwardly between the sleeve l5 and the core l, as best showninlfligure l. Outwardly extending lugs 2.1i are formed at the upper end ofthe dogs these lugs project outwardly into and are disposed within the windows or openings I8 in the sleeve. The upper portion of each lug is beveled,` or 'tapers downwardly and outwardly, to .provide a wedge surface 25 which is adapted to be' engaged by the sleeve I at the upper edge Illia offthe opening or window i8. The offset or rec es's23 in the upper portion kof each dog is loosely connedmithin the annular space between the core and sleeve, whereby the dog may undergo a limited' longitudinal and lateral motion therebetween.
The llower end of *eachY dog `or supporting elementis provided with a beveled surface 26 on itsV outer'edge which is adapted to slide upon a corresponding inwardly and downwardly extending inclined surface 27 formed at the lower end of the slots Il inthe sleeve, whereby thedog `is movably supported on such' inclined surface. Thelower inner Vend portion yof each dog is also formedwith a slight bevel 2S to permit the dog to slide readily over a well device A, as willfbe hereinafter more fully explained.
Ity will be seen, thereforathat the suprting elements or dogs 2D are rnovably confinedwithin the Aslots, ll, and that outward displacement'4 of Said. .does from the Slotsis prevented by the en- The sleeve is provided with In addition, the
gagernent of the lower end of each dog with the inclined surface 21 at the lower end of each slot and the engagement of the upper portion of the dog with the sleeve between the upper end of the slot ll and the window I8, while inward displacement of the dog is prevented by the engagement of the inner portion of the dog with the core il). A push ring 3S is slidable in the annular space between the sleeve andthe core above the dogs, and is adapted to engage the upper ends of said A helical coiled spring 3| is also positioned within the annular space between the enlarged bore IS of the sleeve and the core lil and is confined between the push ring 39 and a transversely extending pin 32 mounted in said core and movable therewith in the enlarged bore l5 of the sleeve. With the parts of the retrieving tool in theposition shown in Figure 1, the spring 3l isunder compression and acts downwardly upon the push ring 30 to urge the dogs 2li downwardly within the slots vIl in the sleeve, thus causing the lowerends of the `dogs to be moved inwardly on the inclined surfaces 2 at the lower ends of said slots. The lower ends of the .dogs may,` however, move upwardly and outwardly along such inclined surface upon being forced upwardly against the force exerted by the spring. It will be seen, therefore, that the' dogs are' constantly resiliently urged toward leng-aging and supporting position by the action of the spring and push ring 3G, when the parts are in the position shown in Figure 1.
An elongate sub or connecting member 35, having a depending annular skirt 35, is screwthreaded onto the pin ll at the upper end of the core. from the upper cylindrical portion of the core and is positively positioned longitudinally of the sub by the engagement of the sub with the shoulder l2 at the `upper end of the core. The upper portion of the sub is reduced in diameter and is connected, by means of a screw-threaded pin 3l, to a suitable raising and lowering mechanism 33, which may consist of link jars, a weight member or sinker bar, and a socket member (not shown),
by means of which the retrieving tool is connected to a ilexible steel measuring line or cable (not shown), whereby the retrieving tool may be lowered into and removed from the well flow conductor. A set screw 39 'threaded through the side of the sub and engaging the upper end of the pin I l of the core prevents the sub from being loosened or accidentally removed from the core.
A helical coiled spring 'is positioned in the annular space between the vsliirt 36 of the sub andthe core H3, and has its upperend engage ing :the underside .35a of ythe sub and its lowery end acting upon the upperendof the sleeve l5, as
is clearly shown in Figures l .and 5. This spring tends to` urge the sleeve l5 downwardly, from the position shown in Figure lto. the vposition shown in Eigure 5, whereby the wedge surfaces 25 at the upper -ends. of thedogsv 2li areengaged by the downwardly facing edges 43a of the sleeve the dogs is narrower than the upwardly 'facing shoulder l on the core or body Iii, the dogswill pivot,` at the Ijunction of thedownwardly facing shoulder 22'V with the. inside of the dogs,.upon.
the outer-edge of the-core shoulder lil, .wherebyA such inwardymovement ofthe upper.' ends of the'. dogs swings the lower endsof the dogs outwardly'-V The skirt 36 surroundsand is spaced from engaging position, as clearly shown in Figure 5. Downward movement of the sleeve I5 with respect to the sub rst moves the dogs downwardly until the shoulder 22 engages the upwardly facing seat I=4 on the sub to stop further downward movement of the dogs. En-gagementof the edge I8a of the sleeve at the upper end of the windows I 8 with the wedge surfaces 25 at the upper end of the dogs then swings the upper ends of the dogs inwardly to the position shown in Figure 5, where-by the lower ends of the dogs `are swung outwardly from engaging position to the retracted or disengaged position shown in Figure 5.
For releasably holding the sleeve I5 in its uppermost position, shown in Figure l, wherein the dogs or supporting elemen-ts 2B are permitted to move to their engaging position, a frangible member or pin 4I is provided in a transverse hole 42 extending diametrically through both the sleeve I5 and the core I, as clearly shown in Figure l. The upper peripheral portion of the sleeve is reduced slightly in diameter, and .a cap or cover ring 43, having an inwardly directed annular ange 44 at i-ts upper end, surrounds the reduced upper portion of the sleeve I5 and confines the pin 4I in the transverse hole 42. The inwardly directed flange 44 engages over and is supported upon the upper end of the sleeve, being held securely in place thereagainst by the helical spring `40. Thus, when the pin 4I is sheared, in the manner which will be hereinafter explained, the sheared portions of the pin are prevented from falling out of the hole 42 bythe cap ring 43.
Diametrically opposed openings 45 are formed l in the lower portion of the cap ring to permit insertion of a new shear pin into the hole `42 after the previous pin has been sheared. After the new shear pin has been installed, the cap ring is turned through approximately 90 degrees to position the openings 45 out of alignment with the shear pin 4I, whereby the shear pin is positively retained in the transverse hole 42 by said cap ring.
In use, the tool is assembled as shown in Figure l and connected to the exible line lowering and raising mechanism by means of which it may be lowered into the well flow conductor T. It will be noted that, with the sleeve I5 held in'iIt-s uppermost normal position by the shear pin 4l, Vas illustrated in Figure l, the dogs 20 may each independently undergo a limited longitudinal movement in the slots I6, since the dogs are not connected together. The dogs are normally urged downwardly within the slots I6 by the compressive force of the spring 3|, the lower ends of said dogs having the supporting element 2| -thereon being urged inwardly into the bore of the sleeve I5 by the inclined surfaces 21 at the lower ends of the slots.
Any suitable well ldevice A may be removed fro-m the conductor T by means of the tool herein described, and the type shown is one such as is illustrated and described in the patent to H. C. Otis, No. 1,972,791, issued `September 4, 1934, and includes a mandrel 50 having a slip assembly slidably mounted thereon. The slip assembly includes a slip carrier 5I which is in the form of a sleeve slidable on the mandrel and having an external annular flange 52 at its upper end.
The sleeve I5 and the dogs 20 of the retrieving tool may be passed downwardly over the flange 52, so that the flange enters the bore of the sleeve and moves upwardly between the dogs until the shoulder at the lower end lof the flange is moved above the supporting projections or hooks 2I yat the lower end of the dog, whereby the well device is suspended .from the retrieving tool.
The bore of the sleeve I5 of the retrieving tool is preferably made of. such a diameter that it slides over and fits rather closely about the ange 52 of the well device, andthus forms .an inverted receptacle or bowl for receiving the upper end of the well device. The flange 5'2 is, therefore, confined against any substantial lateral movement within the sleeve |55, and it is only necessary that the hook or projection 2I on one of the dogs engage under the shoulder yat the lower end of the flange to suspend the well device, although engagement of both dogs is preferable. It will, therefore, be seen that only a single dog is actually required for successful operation of the retrieving tool. Further-more, since the dogs are each movable independently of the other, should one of the dogs be rendered inactive for any reason, as by becoming stuck in an inoperative position because of the presence of sand or other extraneous matter, or in the event the lower portion and supporting projection or hook of one of 'the dogs be broken off, the other dog may nevertheless function to engage yand support the .well device. f
Slips 53 are movably connected to and depend from the carrier 5I of the well device A and are expansible into gripping engagement vwith the bore' wall of the tubing or conductor T upon upward rvmovement of the mandrel with respect to said slips, as is clearly set out in the aforesaid Otis Patent,I 1,972,791. It will readily be seen, therefore, that when the sleeve I5 and'projections or hooks 2| of the supporting dogs have been moved downwardly over the upper end of the well device until the projections or hooks are positioned below the flange 52, the mandrel 50 may be engaged by the lower end of the core I0 of the retrieving tool to force the mandrel downwardly and permit the gripping slips to move to retracted position, whereupon the well device is supported upon the projections or hooks 2I of the retrieving tool and may be lifted upwardly from the well tubing thereby.
When removing the well device from the well tubing, the retrieving tool is lowered over the upper end of the well device until the bevels 28 on the inner lower end ofthe dogs engage the upper end of the flange 52 on the slip carrier of the well device. Continued downward movement of the retrieving tool moves the dogs upwardly within the slots I'I to permit the hook elements or projections 2I to move outwardly and down past the flange, as illustrated in Figure 2. It is to be noted that, when the hook elements have moved below the flange 52, the lower end of the core I0 of the retrieving tool will engage the upper end 'ofthe mandrel 56 before the -lower end of the sleeve I5'r engages the enlarged flange 5Ia of the slip carrier. Thus, the mandrel 50 may be driven downwardly, to release the slips 53 connected to the slip carrier, byl `downward blows imparted to the mandrel through the core I0.
When the slips have been released, the hooks or projections' 2l on the dogs will engage under the flange 52, to permit lifting the'slip carrier,v
slips and mandrel of the well device A upwardly within, the well tubing. In this position, the beveled lower ends 26 of the dogs engage and ride downwardly and'inwardly on the inclined surfaces 2'IY at the lower ends of the slots II in the sleeve. Thus, positive engagement of the with the flange 52 of the well device.
hooks or Vprojections 2I with the well device is assured, and the well device maybe readily lifted and removed from the well tubing.
It may sometimes occur that the well device A becomes stuck in the well tubing for some reason, whereby the slips may not be retracted in the Ymanner just described. In such event, the retrieving tool may be released from its engagement with the slip carrier by pulling or jarring upwardly with the running mechanism to fracture or shear the pin AI. When thepin 4I has been sheared, the spring will immediately and automatically move the sleeve I downwardly with Vrelation to the core I9. This downward movement of the sleeve causes the edges Illa of the windows I3 to engage the upper ends ofthe dogsand move the dogs downwardly with respect to the core until the shoulders 22 engage the seat It on the core. A continued downward movement of the sleeve causes the edges I8a to engage the wedge surfaces 25 to swing the upper ends of the dogs inwardly to the position shown in'. Figure 5, and thus swing the lower ends of the supporting dogs outwardly from engagement In such position, .the hooks or projections 2l on the dogs do not project into the bore of the sleeve I5 and the entire retrieving tool may be withdrawn from the well.
It will be noted that such downward movement of the sleeve I5 `moves Vthe dogs 20 downwardly until :the shoulders 22 engage against the seat I4 on Athe core. In this position, the spring 3l has no further effect upon the dogs. Furthermore, since the spring is conned between the cross pin 32 and does .not act upon the sleeve I5, the spring 3| is rendered inactive and the downward movementk of the sleeve is not resisted or aiected by suchV spring, The spring '40 thus positively and automatically moves the sleeve I5 downwardly until the edge IBa of the sleeve at the upper end of the windows engages the wedge-surface'2'5 at the upper ends of the dogs and positively moves the dogs to non-engaging retracted position.
Downward movement of the sleeve vI5 is limited byengagement/of the upper Vends vof the slots I7 From the foregoing, it will be seen that a re- I trieving tool has been provided which vhas dogs or supporting elements thereon lwhich are independently and individually movable through a limited distance longitudinally -land laterally within slots I'l formed in the sleeve I5, and which are normally urged inwardly toward engaging position bythe inclined surfaces 2;'Iat the lower ends of the slots and the action of the spring 3I upon the upper ends of 'the dogs. The `inclined surfaces-'21 tend to lhold the hooks -or projections ZI on the lower ends of theedogs in tight engagement with the retrieving-connection, such asthe flange 52,V on the well /device which is engaged :by the retrieving tool. Any upward pull imparted to the rsleeve f5 will ten'd 'to' move the hooks further inwardly to increase their gripping action on the flange and assure Athat engagement with such flange isV maintained. Furthermore, the portion of the Asleeve I5 below the slots and inclined surfaces 2 provides additional support for the dogs 2`0,so lthat theV entire weight of the well device is not carried by the dogs alone, but by lboth the dogs and sleeve.
Itrwill also be seen that the hooks or projections .ZI )of the dogs are quickly and automatically moved to disengaged position when the shear pin t ,is fractured and the sleeve is moved downwardly with relation to the core il) by the spring te.
It will particularly be noted that the provision of the wedge surfaces 25 at the upper ends o the dogs and the pivotingvof the dogs on the outer edge' of the shoulder I on the core provide for positive retraction of the dogs from engaging or supporting position when the edge Ila of the sleeve at the upper end jot the windows yIii in the sleeve engages and moves downwardly along said wedged surface.
The foregoing description of the invention is explanatory only, and changes in details of the construction illustrated may be made by those skilled in the art, within the scope of the appended claims, without departing from the spirit or" the invention.
VJl/'hat we claim and desire to secure by Tnetm ters Patent is:
l, A retrieving tool for retrieving well devices having a mandrel and a gripping mechanism with a flanged carrier slidable on the mandrel, said retrieving tool including, a core, a sleeve movable on said core and having an elongate slot therein with an inwardly and downwardly inclined surface at the lower end of said slot, a supporting element carried by said sleeve with its lower end extending in the slot and movable longitudinally with relation to said core and sleeve, resilient means on the core normally urging said supporting element longitudinally into engagement with the inclined surface at the lower end of the slot for moving the lower end of said supporting ele-ment into supper position, said sleeve being arranged to telescope over the upper end of the ilanged carrier of` the well device to hold said carrier flange in position to be supported by the supporting element, means on the lower end oi the core within the sleeve for engaging the upper end of the mandrel or the well device for applying force downwardly thereto while the 4supporting ele ment is disposed in supporting position below the fra-nge of the carrier whereby the mandrel may be .moved downwardly with respect to 'the gripping mechanism to permit the ywell device to be released and `removed from the well, a downwardly facing stop shouldr on'the inner side of thesupporting velement adjacent the core,
an upwardly facing stop shoulder on the lower end of the core normally spaced below and positioned to .be engaged by the downwardly facing stop shoulderon the supporting element for limi ing downward movement of the supporting elenientfwith respect to the core, wedge means at the upper end of the supporting element arranged to be engaged by the sleeve upon downward movement of the sleeve with respect to the vcore kto move the supporting element to releasing position, and releasable means for normally 'preventin movement or the sleeve relative to the core. .A retrieving tool including, a core, a sleeve Y, movable on said-.core and extending below the core and forming a bowl open at the bottom adapted to be Vplaced over a well device in a well flow conductor, said sleeve having spaced longitudinal slots therein with inclined surfaces at the lower ends -of said slots, supporting members loosely conned between said core and sleeve and each independently movable longitudinally and laterally with relation to said core and sleeve and each having its lowerI end extending in one of the slots, resilient means carried by the core normally urging said supporting members longitudinally of the slots into engagement with the inclined surfaces at the lower ends of the slots for moving the lower ends of said supporting members into supporting position, a downwardly facing stop shoulder on each supporting member, an upwardly facing stop shoulder on the core normally spaced below the stop shoulders on the supporting members and positioned to be engaged by the downwardly facing stop shoulders of the supporting members for limiting downward movement of said supporting members with respect to the core, wedge means at the upper end of each of the supporting members, means on the sleeve arranged to engage the wedge means of the supporting members upon downward movement of the sleeve with respect to the core to move the supporting members to releasing position, and releasable means for normally preventing movement of the sleeve relative to the core.
3. A retrieving tool including, an elongate core having an upwardly facing stop shoulder near its lower end, an elongate tubular sleeve slidable on the core and extending below the core and forming a bowl open at its lower end adapted to be placed over a well device in a well conductor, said sleeve having spaced elongate longitudinal slots formed therein extending below the lower end of the core and each having an inclined surface at its lower end, supporting elements loosely confined between said core and sleeve and each movable longitudinally and laterally independently of the other and with relation to the core and sleeve, the lower ends of said supporting elements being movable into and out of supporting position, resilient means carried by the core and acting upon the supporting elements to normally urge said supporting elements longitudinally of the slots into engagement with the inclined sur- 10 face at the lower end of said slots for moving the lower end of the supporting elements into supporting position, a downwardly facing shoulder on each of the supporting elements normally spaced from the upwardly facing shoulder at the lower end of the core and arranged to engage the shoulder on the core for limiting downward movement of the supporting elements with respect to the core, wedge means at the upper end of each supporting element, engaging means on the sleeve arranged to engage the wedge means at the upper end of the supporting elements to move the supporting elements downwardly until the shoulders on the supporting elements engage the shoulder on the core to stop further downward movement of the supporting elements, said engaging means then acting upon the Wedge at the upper end of the supporting elements to swing the lower end of the supporting elements to releasing position, resilient means carried by the core and engaging the sleeve and normally urging the sleeve downwardly with respect to the core, and releasable means initially restraining the sleeve in an elevated position with respect to the core and preventing downward movement of the sleeve relative to the core, said releasable means being releasable to permit downward movement of the sleeve relative to the core with respect to the sleeve, such downward movement of the sleeve then causing the supporting elements to be moved to releasing position. K
SAMUEL J. E. MARSHALL. LOWELL M. WILHO-IT.
REFERENCES CITED The following references are of record in the file of this patent:
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