US2549007A

US2549007A - Well packer plugging apparatus

Info

Publication number: US2549007A
Application number: US636829A
Authority: US
Inventors: Thomas M Ragan
Original assignee: Baker Oil Tools Inc
Current assignee: Baker Hughes Oilfield Operations LLC
Priority date: 1945-12-22
Filing date: 1945-12-22
Publication date: 1951-04-17
Anticipated expiration: 1968-04-17

Description

April 17, 1951 T. M. RAGAN WELL PACKER PLUGGING APPARATUS Filed Dec. 22, 1945 IN VEN TOR WifW ATTORNEY Patented Apr. 17, 1951 I 2,549,007 WELL PA'CKER PLUGGING APPARATUS Thomas M. Ragan, Downey, Calif assignor to Baker Oil Tools, Inc., Vernon, Calif., a corporation of California Application December 22, 1945, Serial No. 636,820

. 1 This invention relates to well devices, and more particularly to well packer apparatus employed in the performance of bridging, cementing, acidizing, testing, and similar functions in well bores.

It is sometimes essential or desirable to permit fluid flow through the central passage of a well packer, or like device, and then close this passage against downward flow of fluent substances. Closing of the passage may be accomplished by allowing gravitation of a bridging ball or other element through the fluid in the tubular string to which the packer is secured and into engagement with a companion seat in the packer. Such mode' of closing the passage entails the consumption of variable time that must elapse during dropping of the bridging element through the well tubing, especially through tubing filled with heavy drilling mud or other viscous fluid. In some instances, the bouncing of the ball along the inner wall of the tubing during its downward travel nicks or mars its surface to the point where it will fail to make a fluid tight seal with its companion packer seat. 7

It is, accordingly, anfobject of the present invention to provide animproved apparatus for insuring prompt seating of the bridging element in the packer, by obviating the need for the element to travel through the length of the tubing string to which the packer apparatus is attached.

A further object of the invention is to provide a bridging apparatus that may be secured to a well packer for the purpose of subsequently releasing a retained bridging element for engagement with the packer to. close its central passage, the entire bridging apparatus, with the ex ception of the bridging element, being subsequently disconnectible from the well packer and bodily removable with the tubing string to the top of the well bore, leaving a minimum of material in the well for later removal by a-drilling,

or other operation.

I .Yet a further object of theinvention is to provide a bridging device attachable to a well packer which permits the use of a relatively large bridging element in plugging ofi the central passage through the well packer.

This invention has other objects which will become apparent from a consideration of the embodiment shown in the drawings accompanying and forming apart 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 defined by the claims appended hereto.

Referring to the drawings:

Figure 1 is a longitudinal section through the device of the present invention, with the parts 21 Claims. (01. 166 -13) in the positions they assume when the device is run in a well casing;

Figure 2 is a view similar to Figure 1, showing the device anchored in packed off condition in a well casing and with the running-in string in a partially elevated position to release an initially retained bridging element;

Figure 3 is an enlarged longitudinal section through the bridging element retaining and releasing mechanism of .the apparatus, with the parts holding the bridging element in restrained position; and

Figure 4 is a cross-section taken along the line 4-4 in Figure 3.

The well packer Aand bridging device B illustrated in the drawings are usually lowered within a. string of easing Con the lower end of a suitable tubular string D, such as tubing or drill pipe, to the desired point at which the packer is to be anchored to the casing in packed off condition. The well packer may be of any suitable construction, the one shown being of the type specifically described in United States Letters Patent No. 2,121,051.

- Essentially, the packer A consists of a tubular body In, to which the lower end of the bridging device B is secured. The body has an inflatable packing sleeve ll surrounding it, whose upper and lower ends are suitably secured, respectively, to upper and lower conical expanders l2, [3 at: tached tothe body originally by one or more shear screws l4, l5. The outer surface of the upper expander l2 tapers upwardly and inwardly and is engaged by correspondingly tapered upper segmental slips l6, secured to it originally in retracted position by shear screws ll. Similarly, the outer surface of the lower expander 13 is tapered inwardly in a downward direction and engages correspondingly tapered lower segmental slipslB, secured to'it originally in retracted position by shear screws l 9. The upper end of the body I!) carries an abutmentring 20 engageable by theupper end of the upper segmental slips 16, and the lower end of the body is provided with a lower abutment 2| .for engagement withthe lower end of the lower segmental slips l8.

A'valve housing andguide 22 is secured to the lower endof the body and has a back-pressure ball valve 23, preferably buoyant in cement slurry, originally 'preventedlfrom engaging its companion valve seat 24 onIthe'body by a retainer arm 25 whichholds the ball against the housing to one 'side of the central passage 26 through the body. The armextends upwardly from a trip ball seat 21, originally secured in the lower end of the. valve housing by a suitable shear screw 28.

As aforementioned; the bridging ball retaining and releastingdeviceB is suitably secured to' the upper end of the well packer, Specifically,

responding valve element may be confined. The

bridging ball, when released, may drop downwardly a comparatively short distance undergravitational influence through the lower tubular sub 30 and into engagement with a valve seat 34 provided in the upper end of the packer body [0.

The bridging ball 33 is held initially against the inner wall of the chamber 32 to one side of the central passage through the apparatus by a retainer sub 35. This sub" is threaded into the upper end of the housin preferably through the use of a left hand thread connection 35d, and has a depending-arm 33 welded or otherwise securedto-it and extending inwardly in adownward direction towards the axis of the apparatus, where a coaxial depending finger 31, secured to i or integral with the arm, may engage the bridging ball 33, and prevent its dropping downwardly onto'the valve seat- 34 in the packer body. It is to be noted that the finger 37 depending from the arm 36 engages the ball 33 and holds it in the chamber 32 since the distance between the lower end of the finger and the lower downwardly and inwardly tapered wall 32a of the chamber is less' than the diameter of the ball, thereby preeluding dropping of the latter to its bridging position across the packer passageway 26.

Rotation of tubing string D, as to the right, causes unthreading of the retainer sub 35 from the housing and elevates its finger 3? from confining engagement with the bridging ball 33 until the dis'tance betweenthe finger and the tapered wall 32a of the chamber is'greater than the diameter of the ball, which then allows the latter to drop downwardly through the lower sub 33 and onto the bridging ball valve seat 34, closing the central passage of the apparatus against downward flow of fluent substances. The apparatus is made up as disclosed in Figure l, with theretainer sub 35 threadeddownwardly into the bridging ball housing 29 to its fullest extent toconfinethe bridging ball 33, and with the housing sub itself 30 threaded into the upper end of the body ii] of the well packer. As assurance against unscrewing of the lower sub 30 from the packer preparatory to upward unthreading of the retainer sub 35 from the hous ing 29, the lower sub, may be 'preventedfrom rotating originally bya lateral shear screw 38 threaded through the body and into the sub. The retainer. sub 35 issecu'red to the lower end of the tubular string D, by means of which the apparatus is lowered through the well casing C to' the desired packer anchoring point. When this positionis reached a trip ball 39 is allowed to gravitate or is pumped down through the tubing string, through the central passage in the retainer' sub 35, past the confined bridging ball valve member 33, through the lower sub 33 and body central passage 26, around the back-pressure ball 23 and retainer arm 25, and into engage ment with the trip ball seat 21 at the lower end of the apparatus.

Engagement of the trip ball 39 with its seat 21 closes the apparatus against further downward flow 'of fluid and enables pressure to be built up to a sufficient degree to initiate setting of the packer. The fluid under pressure may pass outwardly of the body through its lateral ports 4|] opening into the interior of the packing sleeve I I, elongating the latter in an upward direction and exerting an upward force against the upper expander 12 to shear the expander and slip screws l4, 11, moving the expander upwardly along the body and the upper slips i6 radially along the abutment 2!] into anchoring engagement with the wall of the casing.

Sincethe upper slips l8 prevent further upward movement of the upper expander 12, the taking of an elevating strain on the tubing string D and attached bridging device B and packer body 19 first-compresses the packing sleeve I linto fluid tight sealing engagementwith the packer body and-easing wall and then shears the lower expander and slip screws l5, 19, causing the lower abutment 2| to shift the lower slips It upwardly along the lower expander l3 and radially outward into anchoring engagement with the wall of the casing. Thereafter, an increase of the fluid pressure to a predetermined degree shears the trip ball seat screw 28 and blows the seat 21, together with the back-pressure ball retaining arm 25, downwardly out of the packer apparatus, freeingthe back-pressure ball valve 23 for en-' gagement with its companion seat 24. The packer is held in its set position by engagement of a ratchet ring t i in the upper expander 12 with annular ratchet teeth 42 on the body, which-precludes downward movement of the latter with respect to the expander, slips and packing.

Further details of the construction and operation of the well packer of the type illustrated may be found in the patent above referred to.

In one use of the apparatus, cement slurry' or other fluid may be pumped through the tubing string and apparatus for discharge from the lower end of the packer. The bleeding ofi of pressure within the tubing string allows the back-pressure ball 23 to move upwardly and engage its companion seat 24, preventing return or upward flow of fluid through the packer apparatus.

thus prevents downward passage of fluid through the well packer A, and since the back-pressure valve member 23 prevents upward passage of fluid through the apparatus, a bridging packer is provided which prevents-flow of fluid through the apparatus in both directions. a

It is desired to retrieve the entire bridging device 3 connected to the packer from the well bore after the bridging ball has been released. To accomplish this purpose, a stop ring 43 is secured to the upper end of the bridging ball housing 29 and is provided with an inturned flange or shoulder 44 engageable by an external flange or shoulder 45' on the retainer sub-35; Such engagement occurs after partial upward unthreading of the sub 35 from the housing 29 which is sufficient in extent to free the bridging ball 33 and allow it to drop onto its companion valve seat 34. However, as soon as engagement betweenthe flanges 4'4, 45 occurs, further rotanumber of turns to the right, the lower sub is completely unthreaded from the packer body, allowing the bridging device B to be removed to the top of the well bore on the lower end of the tubular string D.

The shear screw 38 need not necessarily be employed for the purpose of insuring that the upper left hand threaded connection 35:: will unscrew before the left hand threaded connection 3|. By suitably choosing the respective pitches of the upper and lower left hand threads, the former willbecome loosened and begin unthreading prior to the lower connection, upon turning of the tubular string D to the right. For example, the two threaded connections could have the same pitch, but if the pitch diameter of the upper thread 35a were greater than that of the lower, the former-would unscrew first until the shoulders 44, 55 abutted, whereupon the lower sub 30. would be unscrewed from the packer body [0. Again, the pitch of the upper thread 35a may be less than that of the lower thread 3!,

which would also permit the former to unscrew prior to the latter. However, the use of the shear screw. 38 is advantageous as a precautionary measure.

' Since the finger 31 is disposed coaxial of the apparatus, rotation of the retainer sub 35 continues the position of the finger in such coaxial relationship, permitting free upward movement of the arm 35 during elevation of its retainer sub. The employment of the relatively small diameter coaxial finger 3! permits a comparatively large bridging ball 33 to be employed for engagement with the relatively large valve seat 34 in the packer body, and does not require substantial restriction of the packer passageway 26.

The complete removal of the bridging device B, with the exception of the bridging ball 33, which purposely remains in engaged position on its valve seat 34 to close the body passage 26, permits the bridging apparatus to be used over and over again. Such withdrawal from the well bore leaves only the packer A anchored to the casing for subsequent removal by a drill bit, whenever the packer obstruction in the well casing is to be eliminated. In other words, the apparatus described does not add any elements to the packer apparatus requiring drilling out at some later date.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. Well apparatus, including tubular means providing a fluid passage, valve means within said tubular means, restraining means attached to said tubular means and engaging said valve means to prevent its movement into said passage,

means on said restraining means for connecting said restraining means to a running-in string, said restraining means being rotatable by said running-in string with respect to said tubular means to release said valve means for movement through said passage, and coengaging stop means on said tubular means and restraining means for limiting the extent of releasing movement of said restraining means with respect to said tubular means and for preventing rotation of said 6 restraining means with respect to said tubular means.

2. Well apparatus, including a tubular body having a valve seat, a tubular housing detachably secured to said body, valve means within'said housing, restraining means attached I to said housing and engaging said valve means to prevent itsengagement with said seat, means on said restraining means for connecting said restraining means to a running-in string, said restraining means being movable by said runningin string with respect to said housing to release said valve means for engagement withsaid seat, and coengaging stop means on said housing and restraining means for limiting the extent of valve releasing movement of said restraining means with respect to said housing, in order to couple said restraining means to said housing and enable said housing to be detached fromsaid body.

3, Well apparatus, including tubular means providing a fluid passage, valve means within said tubular means for closing said passage, tubuto thread said restraining means with respect to said tubular means to a position releasing said valve means for movement to passage closing position, and coengagingstop means on said tubular means and tubular restraining means for limiting the extent of their relative rotation after release of said valve means and for eifecting coupling of said tubular means and restraining means by preventing their further rotation with respect to each other.

4. Well apparatus, including tubular means providing a fluid passage, a valve element within said tubular means movable downwardly to close said passage, restraining means attached to said tubular means and engaging said valve element to prevent its downward movement to passage closing position, means on said restraining means for connecting said restraining means to a rune ning-in string, said restraining means being movable by said running-in string with respect to said tubular means to release said valve element-and allow such downward movement to passage closing position, and coengaging stop means on said tubular means and restraining means for limiting the extent of their relative movement after release of said valve element.

5. Well apparatus, including tubular means providing a fluid passage, a valve element within said tubular means movable downwardly within said passage, restraining means attached to said tubular means and engaging said valve element to prevent its downward movement within said passage, means on said restraining means for connecting said restraining means to a runningin string, said restraining means being movable upwardly by said running-in string with respect to said tubular means to release said valve element-for downward movement within said passage, and coengaging stop means on said tubular means and restraining means for limiting the extent of such upward movement of said restraining means after release of said valve element.

6. Well apparatus, including tubular 'means providing a fluid passage, a valve element within asi es? said tubular mean mtvatie dewnwaraiy within said passage, tubular restraining means threadedly attaehed to said tubular means and engaging said valve element to prevent its downward movement within said passage, means on said tubular restraining means-for connecting said tubular restraining means to a tubular string, said restraining means being rotatable by said tubular string to thread said restraining means upwardly with respect to said tubular means and release-said valve element for downward movement within said passage, and coenga'ging stop means on saidtubular means and restraining means for limiting the extent of such upward threading movement of said restraining means, in order to non-rotatably couple said tubular restraining means to said tubular means. Y

.-7. Well apparatus-,- including a tubular body having a valve seat, a tubular housing detach ably secured to said body, a valve element within said housing movable downwardly therewithin into engagement with said seat, tubular restraining means thr'eadedly attached to said housing and engaging said valve element to prevent its downward movement into engagement with said seat, means on said tubular restraining meam for connecting said tubular restraining means to a tubular string, said restraining means being rotatable by said tubular string to thread said restraining 'r'neans upwardly with respect to said hdusing and release said'val've element for downward'move'ment onto said seat, and coen'g'agingstop means on said housing and restraining means for limiting the extent of such upward threading movement of said restraining means, in "order to non-rotatably couple said tubular restraining means to said housing and enable said housing to be detached from said body.

8. Well apparatus, including a tubular body having a valve seat, a tubular housing detachably secured to said body, a valve element within said housing movable downwardly therewithin into engagement with said seat, a tubular retainer within said housing engaging said valve element to preventits downward movement into engagement with'said seat, a left-hand threaded connection between said retainer and housing for elevating said retainer with respect to said ho-us ing upon rotation of said retainer to release said valve element and allow its engagement with said seat; and coenga'ging stop means'on said housinga'nd retainer for limiting the extent of such elevation of said retainer after release of said valve element, in order tonon-rotatably couple said retainer to said housing and enable said housing to be detached from said tubular body. a

9. Well apparatus, including a tubular body having a valve seat, a tubular housing detachably secured to said body, a valve element within said housing movable downwardly into engagement with said seat, a tubular retainer attached to said housing by a left hand threaded connec tion, said retainer engaging said valve element when threaded downwardly within said housing to hold said valve element to one side of said housing and prevent its downward movement onto said valve seat, and said tubular retainer being rotatable to effect its threading upwardly with respect to said housing to a position releasing said-valve element for downward movement into engagement with said seat, and coengaging stop means'on said housing and retainer foi limiting the extentof suc-lrupwar'd threading movement after release of .said valve. element, in order to 8 ndn rotatab ly couple said -retainerto said housing and enable said housing to be detached from said tubular body. I I

10. Well apparatus; including a tubularbo'dy having a valve seat; a tubular housing detachably secured to said bbdy, a ball within said housing adapted to gravitate into engagement with said seat, a tubular retainer attached to said housing and engaging said ball heam a lower position with respect to said housing tdhold said ball to one side of said housing and prevent its "gravitation onto said valve seat, said tubular retainer being movable upwardly with respect to said housing to a position releasing said ball for gravitation into engagement with said seat, and coengaging stop means on said housing and retainer for limiting the extent of upward movement of said retainer relative to said housing after release of said ball. 7 v l ll. Well'appar'ajtus, including a well packer having a valve seat; a tubular housing detachably secured to said packer; a valve element within said housing movable downwardly into engagement with said seat, 'a tubular retainer attached to said housing by a left hand threaded connection, said retainer engaging said valve element when threaded downwardly within said housing to hold said valve element against downward movement onto said valve seat, and said retainer being rotatable to eifect its threading upwardly with respect to said housing to a position releasing said valve element for downward movement into engagement with said seat, and coenga'gjng stop means on said housing and, retainer for [pre venting further relative threadedmovementinan upward direction between said housing and retaine'r after release of said valve element, in order to non-rotatably couple said retainer to said housing and enable said housing to be detached from said well packer.

12. Well apparatus, including a tubular housing, a valve element within said housing, a tub'u la r retainer threadedly attached to said housing, said retainer engaging said valve element to prevent its downward movement with respect to said housing, saidretain'er being rotatable with fespect to said housing to shift it longitudinally ta valve element releasing position an'd coengag ing stop means on said housing and re a'mer rar limitingthe extent of such longitudinal movemerit, after release of said valve element, to nonrotatably couple said retainer to said housing,

13. Well apparatus, including a tubular hous mg, a valve ball within SaidY hOUSiDg, a tubular retainer threadedly attached to said housing, said retainer having a finger coaxial of said housing and engageable with said ball to prevent its downward movement with respect to said housing, said retainer being rotatable withrespeflct to said housingto' shift it longitudinally to ball releasing position, and coengaging stop shoulders on said" housing and retainer for limiting the extent of such longitudinal movement, after release of said ball, to nonrotatably couple said retainer to said; housing.

} l4. We'll apparatus, including a well paeker having-avalve seat, a tubular housing 'detachably secured to said well packer, a ball within said housing, a tubular retainer attached tosaidhousing by a left hand threaded connection, said retainer having a finger coaxial of said housing and engageable witli said ball to prevent its downward movement into'en'gag'ernent with saidseat. said eamen-ag ng rotatable with respect to said '18 housing is elevate and'release said fin er from engagement with said ball and permit its downward movement onto said seat, and coengaging stop shoulders on said housing and retainer for positively limitin the extent of threading of said retainer with respect to said housing in one direction, in order to non-rotatably couple said retainer to said housing and enable said housing to be detached from said well packer.

15. Well apparatus, including a well packer having a valve seat, a tubular housing secured to said well packer by a left hand threaded connection, a ball within said housing, a tubular retainer attached to said housing by a left hand threaded connection, said retainer having a finger coaxial of said housing and engageable with said ball when in a lower position to prevent its downward movement into engagement with said seat, said retainer being rotatable with respect to said housing to elevate and release said finger from engagement with said ball and permit its downward movement onto said seat, and coengaging stop shoulders on said housing and retainer for positively limiting the extent of threading of said retainer with respect to said housing in the releasing direction, in order to non-rotatably couple said retainer to said housing and enable said housing to be unthreaded from said well packer.

16. Well apparatus, including tubular means providing a fluid passage, valve means within said tubular means, restrainin means attached to said tubular means, said restraining means and tubular means cooperatively engaging said valve means to prevent its movement into said passage, means for connecting said restraining means to a running-in string, said restraining means being rotatable by said running-in string with respect to said tubular means to release said valve means for movement through said passage, and coengaging stop means on said restraining means and tubular means for limiting the extent of releasing movement of said restraining means with respect to said tubular means and for preventing rotation of said restraining means with respect to said tubular means.

17. Well apparatus, including a tubular body having a valve seat, a tubular housing detachably secured to said body, Valve means within said housing, restraining means attached to said housing, said restraining means and housing cooperatively engaging said valve means to prevent its engagement with said seat, means for connecting said restraining meansto a running-in string, and said restraining means being movable by said running-in string with respect to said housing to release said valve means for engagement with said seat, and coengaging stop means on said restraining means and housing for limiting the extent of movement of said restraining means with respect to said housing, in order to couple said restraining means to said housing and enable said housing to be detached from said body. 7

18. Well apparatus, including tubular means providing a fluid passage, a valve element with-'- in said tubular means movable downwardly to close said'passage, restraining means attached to said tubular means, said restraining means and tubular means cooperatively engaging said valve element to prevent its downward movement to passage closing position,. means for connecting said restraining means to a running-in string,

said restraining means being movable by said running-in string with respect to said tubular means to release said valve element and allow such downward movement to passage closing position, and coengaging stop means on said tubular means and restraining means for limiting the extent of their relative movement.

19. Well apparatus, including a well packer having a valve seat, a tubular housing detachably secured to said packer, a valve element within said housing movable downwardly into engagement with said seat, a tubular retainer attached to said housing by a left hand threaded connection, said retainer and housing coopera tively engaging said valve element when said retainer is threaded downwardly Within said housing to hold said valve element against downward movement on to said valve seat, said retainer being rotatable to eflfect its threading upwardly with respect to said housing to a position releasing said valve element for downward movement into engagement with said seat, and coengaging stop means on said housing and retainer for limiting the extent of their relative rotation, in order to non-rotatably couple said retainer to said housing and enable said housing to be detached from said packer.

20. Well apparatus, including a tubular housing, a valve element within said housing, a tubular retainer threadedly attached to said housing, said retainer and housing cooperatively engaging said valve element to limit its downward movement with respect to said housing, said retainer being rotatable with respect to said housing to shift it longitudinally to valve element releasing position, and coengaging stop means on said housing. and retainer for limiting their relative longitudinal movement, in order to non-rotatably couple said retainer to said housing.

21. Well apparatus, including atubular body having a valve seat, a tubular housing detachably secured to said body, valve means within said housing movable downwardly into engagement with said seat, a tubular retainer attached to said housing and engaging said valve means when in a lower position with respect to said housing to hold said valve means to one side of said housing and preventits downward movement on to said valve seat, said tubular retainer being movable upwardly with respect to said housing to a position releasing said valve means for downward movement into engagement with said seat, and coengaging stop means on said housing and retainer for limiting the extent of upward move ment of said retainer relative to said housing after release of said valve means, in order to couple said retainer to said housing and enable said housing to be detached from said body.

THOMAS M. RAGAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Date