US2644524A

US2644524A - Tubing and well tool coupling

Info

Publication number: US2644524A
Application number: US707664A
Authority: US
Inventors: Reuben C Baker
Original assignee: Baker Oil Tools Inc
Current assignee: Baker Hughes Oilfield Operations LLC
Priority date: 1946-11-04
Filing date: 1946-11-04
Publication date: 1953-07-07
Anticipated expiration: 1970-07-07

Description

July '7, 1953 R. BAKER 2 6 4,524

TUBING AND WELL TOOL COUPLING Filed Nov. 4, 1946 2 Sheets-Sheet 1 ieaben (Zia Kw hwm Filed NOV. 4, 1946 I 2 Sheets-Sheet 2 July 7,1953 R. c. BAKER 2,644,524

TUBING AND WELL TOOL COUPLING MiG/V70? Elan/2 6'. 5444' Patented July 7, 1953 TUBING AND WELL TOOL COUPLING Reuben C. Baker, Coalinga, Calif., assignor to Baker OilTools, Inc., Vernon, Calif., a corporation of California Application November '4, 1946, Serial N o. 7 07,664

Claims.

The present invention relates to devices for coupling parts of well tools together.

Certain well tools are positioned in a well bore or casing and have a threaded member adapted for connection to a tubular string. The tubular string is run in the well hole to the location of the Well tool and is rotated to thread it into the latter member. In many instances, the well bore is not vertical, which renders difficult the proper alignment of the tubular string with the tool preparatory to the screwing of the string into the tool. As a matter of fact, misalignment between the parts often prevents them from being threadedly connected at all.

In addition to the foregoing difficulty of ob- "taining proper alignment, another disadvantation of the string. This rotational direction and left-hand thread are chosen to prevent.unthread-,

ing in the joints comprising the tubular string. However, although the joints are tightened upon unscrewing of the tubing string from the well tool, the threading of the former into the latter can occur only upon left -hand rotation of the I tubing string, which may produce loosening or unscrewing of the string at one or more joints along its length.

Accordingly, it is an object of the present invention to provide an improved coupling, which is operable to effect a threaded connection between a tubular strin and a well tool without the necessity for rotating, the tubular string, thus obviating any need for turning the string in a left-hand direction.

Another object of the invention is to provide an improved coupling, which is operable to effect a threaded connection between a tubular string and a well tool despite misalignment between the latter members.

A further object of the invention is a'coupling for efiecting a threaded connection between a tubular string and a well tool by non- .rotatably moving the string into the tool, disconnection between the two being effected by rotation of the tubular string.

Yet another object of the invention is to pro- 'vide a coupling between a tubular string and a stress imposed on the tubular string.

to provide Forms which the invention may assume are exemplified in the following description and illustrated by way of example in the accompanying drawings, in which:

s. 1, 2and 3 are longitudinal sections through a tubing and well tool, illustrating the coupling device in different operative positions.

Fig. 4 is a cross-section taken along the line 4-4 on Fig. 2.

Fig. 5 is a longitudinal section through a well packer and tubing string coupled thereto.

Fig. 6 is a longitudnal section through a tub-' ing string and coupled collar forming part of a casing string.

The invention is disclosed in the Figs. 1 to 5, inclusive, embodiment as effecting a connection between a tubular string of tubing or drill pipe A and a well packer B anchored in a well casing C. The packer includes a tubular. body I0 held against upward movement in the casing C by an upper expander H wedged into an upper set of segmented slips I2 engaging the wall of the casing; the body being prevented from moving in a downward direction by a lower expander l3 wedged into a lower set of segmented slips l4 engaging the wall of the casing. The downward thrust between the body. in and expander I3 may be transmitted through a split tapered lock ring [5 wedged into a tapered groove I6 in the lower expander. A seal between the packer body and casin is provided by a packing sleeve l1 compressed between the upper and lower expanders ll, l3 and expanded outwardly into sealing engagement with the casing wall.

The upper end of the packer body H] has a box 18, or female member, provided with a thread !9, and preferably a left-hand thread, which may be a square thread or any other suitable configuration. The tubing string A is adapted to be coupled to the packer body In by means of a I coupling or latching device mounted on the tubular string. The lower end of the tubular string includes a two part member comprising an upper sub 20 threaded onto a lower sub 2| which has an expander 22 on its exterior around whicha split, externally threaded latch ring or sleeve 23 is disposed. The expander 22 has an external tapered surface 24 inclined toward the longitudinal axis of the tubing string in an upward direction, and the latch ring or sleeve 23 has a corresponding tapered inner surface 25 for engagement by the expander.

A longitudinally extending key 26 is suitably secured, as by welding material. 21, to the lower sub 2|, projecting between the opposed

spaced ends

28, 29 of the latch ring. The key 26 extends outwardly a sufficient distance to insure its engagement with one or both

ends

23, 29 of the latch ring 23 irrespective of the lateral position of the ring on the member 2 l. The key, however, does not project outwardly from the axis of the tubing strin sufficiently to engage the threads IS on the box end 88 of the packer body IE3.

The latch ring 23 has spring-like properties, tending to expand outwardly inherently to a limited extent. The latch ring may move longitudinally with respect to and along the tapered surface 2d of the expander 22, its upward movement being limited by its engagement with a shoulder 30 provided by the lower end of the upper sub 28. The expansion of the latch ring due to its own inherent expansible properties is insufficient to produce its dropping from the lower sub 2| during movement of the tubing String A within the well casing toward or away from the packer B.

To facilitate expansion and contraction of the split latch sleeve 23, longitudinal grooves 3! may be cut or otherwise formed part way into its exterior surface. It is to be noted that the thread 32 on the exterior of the latch sleeve has the same pitch as the mating thread i9 in the box end of the packer body, and that the leading faces 33 of these threads are tapered in a downward and inward direction, whereas their trailing faces 34 correspond to the faces on the square threads I9. In effect, the threads 32 are of general buttress configuration.

Let it be assumed that well packer A has been anchored in the well casing C by suitable means, such as a string of tubing (not shown), which was coupled to the packer body if? by means of its usual left-hand thread engaging the left-hand thread 19 in the body. Following setting of the packer in packed-off condition, this tubing string (not shown) may be rotated to the right and unscrewed from the packer body, and then removed from the well bore.

At some later time, it may be desired to couple a tubular string to the packer. The tubular string A, with its coupling or connecting device at its lower end, is run in the well casing until it reaches the upper end of the packer body it. The range of inherent outward expansion of the latch ring positions its buttress thread 32 laterally beyond the packer body threads 59 by a slight amount, causing its engagement with the upper end of the body l0, as the lower sub 2! is piloted or moved into the upper end of the box l8 (Fig. 1). Such engagement holds the latch ring 23 in an upper position until the cont nued lowering of the tubular string engages the shoulder 33 with the upper end of the latch ring and forces or pushes the latter into the threaded box E8, the tapered leading faces 33 on the ring thread 32 causing the ring to be retracted inwardly as the external threads 32 ratchet over the internal box threads l9. Such inward ratcheting is permitted because of the space 35 which exists between the inner surface 25 of the latch ring and the tapered outer surface 2 on the expander 22 (see Figs. 1 and 2).

Downward movement of the lower sub 2! and connected upper sub 2@, with the latch ring 23 mounted thereon, within the threaded box I8, is

limited by engagement of the tapered upper shoulder 36 on the sub 2% with the tapered end 31 on the packer body it. Following their engagement, the ring 23 inherently expands outward to place its threads 32 in engagement with the box threads !9 (Fig. 3). Thereafter, an upward strain'may be taken on the tubing string A to pull the two part member 2G, 2! upwardly within the latch ring 23, which is held against upward movement by Virtue of engagement of the upper faces 34 of its threads with the lower faces of the square threads is inv the box [8. This upward movement causes the tapered surface 24 on the expander portion 22 of the lower sub 2! to engage the companion tapered surface 25 on the latch ring 23 and hold the latter wedged outwardly into firm and full mating engagement with the threads It in the box end of the packer body (Fig. 5)

The load carrying capacity of the apparatus, including the latch ring or sleeve 23, is sufficient to permit a substantial upward pull or thrust to be .takenon the tubing string A, and this pull "is transmitted to the packer body l0 through the co-engaging tapered surfaces 2 5, 25 and mating threads 32, [9 on the latch ring 23' and box [8. From the body it, the upward pull is transmitted to the casing C through the lower abutment 3B threaded on the packer body ill, lower slips [4, lower expander l3, packing sleeve ll, upper expander H and upper slips !2, whose wickers .39 are embedded in the casing.

In the event that it is desired to release the tubing string A from the packer B, it is lowered a slight distance to relieve the wedging force of the expander 22 from the latch ring 23. Such lowering may continue until the uppersub shoulder cc engages the upper end of the ring, leaving a lateral space 35 between theiinner surface of the ring and the outer surface of the expander (as in Fig. 3). The tubing string may now be rotated to the right, such rotation being transmitted to the latch ring 23 by engagement of the key 25 with one of the ends 29 of the latch ring. As the latch ring rotatesin a right-hand direction, it is threaded upwardly from the box it until it is completely disengaged from the packer body Ii). Such complete :unthreading or uncouplingof the latchring 23 permitsthe entire tubing string Ato be elevated. and withdrawn from the well casing C and bore.

In Fig. 5, the coupling F is applied to a tubing string A connectable to a float collar D forming part of a casing or liner strin E. The collar D is disclosed as provided with a body 4i! of cementitious material, having a central tubular member M provided with a female left-hand threaded box A2 at its upper end. The central passage t3 through the collar communicates with lateral ports at extending through the collar to its exterior. .A ball valve d5 may be included in the collar which opens the passage 43 upon movement in a downward direction and rises into engagementwith a seat 45 in the central passage to prevent upward flow of fluid therethrough.

Assuming that the casing string E. has been run into a well here, the tubing string A with the coupling device F at its lower end may then be run downwardly through the well casing C to effect a coupling with the upper threaded portion 52 of the collar simply by stabbing the lower end 22 of the tubing string into the central tubular member 4| of the collar. As explained in connection with the well packer application of the invention, the latch ring 23 contracts and rides over the threads 4'! in the box 42 until it is disposed completely therewithin, whereupon an upward strain taken on the tubing string A holdsthe latch threads 32 firmly in engagement with the box threads i? in the collar D. If desired, a suitable side seal 48 may be provided in bore.

cooperable well tool.

only be stabbed longitudinally downwardly into vent leakage of fluid therebetween.

One use of the tubing string and collar arrangement A, D disclosed in' Fig. 6 resides in cementing the casing string E'in place after it has been run in the Well bore/The cement slurry may be pumped downwardly through the 'tubing string A for discharge through the side ports 44 in the collar and for upward passage through the annulus between the casing string and wall of the hole. Following completion of the cementing operation, the tubing string ,A may a be rotated to the right to unscrew the latchring 23 from the collar box 42, permitting the tubing string to be removed upwardly from the well As is well known, the ball valve 45 moves upwardly to engage itsseat'45' and prevent ,return fiow of the cement slurry into the casing E.

By virtue of the coupling device disclosed, a

threaded connection may be effected in the well bore itself between the tubing string and a well tool without rotatingv the tubing string. Since the threads in the well tool are preferably left-hand, such rotation, if required, would ordinarily necessitate the left-hand rotation of the tubing string, in order to thread the male member downwardly into the threaded box. Be-

cause of the fact that no rotation is required to accomplish the threaded coupling between the latch ring 23 and the box I8 or 42, it is obvious that the danger of unscrewing the tubing joints at some point along its length is entirely eliminated- However, when it is desired to release the tubing string from the Well tool, the former is rotated in a right-hand direction to unthread the latch ringfrom the box. This directionpof rotation tends to tighten the tubing string joints, rather than to loosen the same.

In view of the ability of the coupling device to move laterally to, a limited extent, misalignment between the lower end of the tubing string and the cooperable box does not preclude proper threaded engagement of the latch device in the The tubing string need the box and the threaded latch member 23 will shift inwardly a sufficient extent to permit its complete insertion into the box l8 or 42, whereupon the tubing string A may be moved upward- 'ly to wedge the threaded male latch member 23 firmly into the cooperable threads H) or 41 on the box. The specific design shown by way of example in the drawings insures that proper mating betweenthethreaded members will remain so long' as an upward strain is imposed on the tubing string. d

While I have shown preferred-forms of my invention, it is to be understood that various changes may be made in their constructionby those skilled in the art without departing from the spirit of the invention asdefined in the appended claims. a Having thus described my invention, what I claim and desire to secure by Letters Patent is g '1. An apparatus of the character described, in-

cluding a well tool having a thread, a member adapted to be connected to said tool, an

expansible and retractable latch ring carried by and movable laterally on said member and also.

longitudinally relative to said member, said ring having a thread companion to said well .tool thread and engageable therewith,.said.ring being adapted to move laterally: in one direction on said member into threaded engagement with' said well tool thread and Qcluding a first member adapted to be positioned laterally in the other-di rection on said member to an extent sufiicient to bring said threads out of engagement with each other to enable said ring to be moved lontive to said ring for moving said ring'laterally of said member in one of said directions.

2. An apparatus of the character described, including a well tool having a thread, a member adapted to beconnected to said tool, an expansible and retractable longitudinally split latch ring carried by and movable laterally and lon gitudinally on said member, said ring having spring-like properties and provided with a thread companion to said well tool thread and engageable therewith, said ring being adapted to move laterally in one direction on said member into threaded engagement with said well tool thread and laterally in the other direction on said member to an extent suflicient to bring said threads out of threaded engagement with each other to enable said ring to be moved longitudinally and without rotation past said well tool thread, said ring and said member being provided with actuating means engageable with said ring and movable longitudinally with. said member relative to said ring for moving said ring laterally of said member in one of said directions.

3. Anapparatus of the character described, including a well tool member having a thread, a

companion member adapted to be connected to a said tool member, an elastic expansible andretractable latch ring movable laterally on said companion member and provided with a thread companion to said well tool member thread, said ring being movable laterally on said companion member to an extent suflicient to bring said threads out of threaded engagement with each other to enable said ring to be moved longitudinally and without rotation past said well tool member thread, means on said companion memtractable latch ring movable laterally on said companion member and provided with a thread companion to said well tool member thread, said ring being movable laterally on said companion member to an extent sufiicient to bring said threads out of threaded engagement with each other t enable said ring to bemoved longitudinally and without rotation past said well tool member thread, means on said companion'memj'ber cooperable with said latch ring to hold said "latch ring thread in. engagement with said well tool member-thread, means providing a rotatable driving connection between said companion memher and latch ring, and coengaging means on said ring and one of said members for moving said ring laterally of said companion member.

, 5. An apparatus of the character described, in-

"in. a well bore and having a thread, a second memher adapted to be connectedto said first member,

, an expansible and'retractable latch ring movable her, said ring having a thread companion to "said thread onsaid first member and engageable therewith, said ring being adapted to move laterally in one direction on said second member into threadedengagement with said first member thread and laterally in the other direction on said second member to an extent suihcient to bring said threads out of engagement with each other to enable said ring to be moved longitudinally and without rotation past said first member thread, said second member being provided with actuating means engageable with said ring and movable longitudinally with said second member relative to said ring for moving said ring laterally of said second member in one of said directions, and means providing a rotatable driving connection between said second member and latch ring.

6. An apparatus of the character described, including a first member adapted to be positioned in a well bore and having a female thread, a second member adapted to be piloted within said first member while said first member is in said well bore, an expansbile and retractable latch ring carried by and movable longitudinally and laterally on said seocnd member, said ring having a male thread engageable with said female thread, said ring being adapted to move in a lateral outward direction on said second member into threaded engagement with said female thread and in a lateral inward direction on said second member to an extent sufficient to bring said threads out of engagement with each other to enable said ring to move longitudinally and without rota tion past said female thread, said second member being provided with actuating means engageable with said ring and movable longitudinally with said second member relative to said ring for moving said ring laterally of said second member in one of said directions.

7. An apparatus of the character described, including a well tool havin a female thread, a member adapted to be positioned within said tool, a retractable inherently expansible latch ring carried by and movable laterally on said member and provided with a male thread engageable with said female thread, said ring tending, by itself, to remain in an outward expanded condition with its male thread in meshing engagement with said female thread, said ring being adapted to move in a lateral outward direction on said member into threaded engagement with said well tool thread and in a lateral inward direction on said member to an extent sufiicient to bring said threads out of engagement with each other to enable said ring to be moved longitudinally and without rotation past said well tool thread, said member being provided with actuating means engageable with said ring and movable longitudinally with said member relative to said ring for moving said ring laterally of said member in one of said directions.

8. An apparatus of the character described, including a well tool member having a female thread, a second member adapted to be positioned within said tool member, a retractable longitudinally split inherently expansible latch ring movable laterally on said second member and provided with a male thread eng'ageable with said female thread, said ring tending, by itself, to remain in an outward expanded position with its male thread in meshing engagement with said female thread, said ring being retracted on said second member to the extent in which the effective outer diameter of said male thread is less than the inner diameter of said female thread, said ring being provided with cam means, and coa'cting means on one of said members adapted to engage said cam means to retract said ring, whereby to disengage said male thread from said female thread upon relative longitudina1 movement between said members.

9. An apparatus of the character described, including a well tool member having a female thread, a second member adapted to be positioned within said tool member, a retractable longitudinally split inherently expansible latch ring movable laterally on said second member and provided with a male thread engageable with saidlfemale thread, said ring tending, by itself, to remain in an outward expanded position with its male thread in meshing engagement with said female thread, said ring being retracted on said second member to the extent in which the eifective outer diameter of said male thread is less than the inner diameter of said female thread, said ring being provided with cam means, coacting means on one of said members adapted to engage said cam means to retract said ring, whereby to disengage said male thread from said female thread upon relative longitudinal movement between said members, and means providing a rotatable driv ing connection between said second member and latch ring.

10. An apparatus of the character described, including a well tool' member having a female thread, a second member adapted to be positioned within said tool member, a retractable longitudinally split inherently expans'ible latch ring carried by and movable laterally on said second member and provided with a male thread engageable with said female thread, said ring tending, by itself, to remain in an outward expanded condition with its male thread in meshing engagement with said female thread, said ring being retractable on said member to the extent in which the effective outer diameter of said male thread is less than the inner diameter of said female thread, said second member being provided with actuating means engag'eable with said latch ring and movable longitudinally with said second member relative to said latch ring for holding said latch ring outwardly with its thread in engagement with said female thread, said ring being provided with cam means, and coacting means on one of said members adapted to engage said cam means to retract said ring, whereby to disengage said male thread from said female thread upon relative longitudinal movement between saidmembers.

11. An apparatus of the character described,

including a well tool'member having a threaded box, a second member adapted to be positioned within said box, a retractable longitudinally split inherently expansible latch ring carried by and movable laterally on said second member and provided with a male thread engageable with the box thread, said ring tending, by itself, to remain in an outward expanded condition with its male thread in meshing engagement with said box thread, said ring being retractable on said second member to the extent in which the effective outerdiameter of said male thread is less than the inner diameter of said box thread, said second member being provided with actuating means engageable with said ring and movable longitudinally with said second member relative to said ring for holding said ring outwardly with its threads in engagement with said box thread, said ring being provided with cam means, coact ins; means o o e; of sai ,m mbersaadapie "t engaeshsaid camgmeans} to; retractsaid ring, whereby tddise aae d ma t read from said .female thread upon relative ;l ongitudinal movement between said embers, and means providing arotatable driving connection between said .second-memberand latchring; n

12,. An apparatusqof ,the; character described, including a well tool having a threaded box, a tubularmember adapted to be positioned within said box,,-a retractable longitudinally split inher en'tly ex'pansible latch ringmovable laterally on said member, said ring being provided with a male thread engageable with the box thread and h ring a downwardly diverging tapered inner face, said ring being retractable on said memto the extent in which' the eifective outer rfof said male thread is less; than the er ameter of said 'box thread, an"expander sa d member having a dow'inwardlydiverging l ed external "suriaceienga'geable with said ta crew-surface on said ring to'hold said latch ring outwardly with its threads in engagement with said box threads, a longitudinally extending key secured to said member and disposed between the opposed ends of said latch ring to provide tive outer diameter of said male thread is less than, the inner diameter of said female thread,

. and coeng-aging cam means on said ring and first in a well bore andfhaving a female thread, a

second member adapted t-obe piloted within said first'member while; said first member is in said well bore,;an, expan sible and retractible latch ring movablelaterally on said second member, said "ring having amale thread engageable with saidfemale thread, said ring being retractible on said second member tothe extent in which the effective outer-diameter of said male thread is less; than the inner diameter of said female thread,:the. lower side of the thread on said ring ibeingtapered to engage the thread on said first member-to, retract'the ring ,out' of threaded engagement" with said first, member :uponlon'gi- Plldihal: movement ;-of said ring 'withrespe'ct to i said firstmemberl a rotatable driving connection between said 1 including a first member adapted to be positioned in a well bore and having a thread, a second member adapted to be connected to said first member, an expansible and retractible latch ring movable laterally on said second member, said ring having a thread companion to said thread on said first member and engageable therewith, said ring being movable laterally on said second member to an extent sufiicient to bring said threads out of threaded engagement with each other to enable said ring to be moved longitudinally and without rotation past said first mem ber threadand coengaging cam means on said ring and first member for moving said ring laterally of said second member.

14. An apparatus of the character described, including a first member adapted to be positioned in a well bore and having a thread, a second member adapted to be connected to said first first member to shift the ring laterally out of threaded engagement with said first member upon longitudinal movement of said ring with respect to said first member.

15. An apparatus of the character described, including a first member adapted to be positioned in a well bore and having a female thread, a

' second member adapted to be piloted within said first member while said first member is in said well bore, an expansible and retractible latch movable laterally on said second member, said ring having a male thread engageable with said female thread, said ring being retractible on said second member to the extent in which the effec- 17. An apparatus of the character described,

, including a first member adapted to be positioned in a well bore and having a thread, a second member adapted to be connected to said first member, an expansible and retractable latch ring mounted on and movable laterally and longitudinally on said second member, said ring having a thread companion to said thread on said first member and engageable therewith, said ring being movable laterally on said second member to an extent sufiicient to bring said threads out of threaded engagement with each other to enable said ring to be moved longitudinally and Without rotation past said first member thread, and

coengaging cam means on said ring and one of said members for moving said ring laterally of said second member out of threaded engagement with said first member thread.

18. An apparatus of the character described, including a first member adapted to be positioned in a well bore and having a, female thread, a second member adapted to be piloted within said first member while said first member is in said well bore, an expansible and retractable latch ring movable laterally on said second member, said ring having a male thread engageable with said female thread, said ring being retractable on said second member to the extent in which the eifective outer diameter of said male thread is less than the inner diameter of said female thread, and coengaging cam means on said ring and one of said members for retracting said ring from threaded engagement with said female thread.

19. An apparatus of the character described, I

- ed to move laterally in one direction on said member into threaded engagement with said well tool thread and laterally in the other direction on said member to an extent sufficient to bring said threads out of engagement with each other to enable said ring to be moved longitudinally and Without rotation past said well tool thread,

said member being provided with actuating means engageable with said ring and movable longitudinally with said member relative to said 11 ring for moving said ring laterally of said member in one of said directions to hold said ring in threaded engagement with said well tool thread.

20. In apparatus of the character described, including a well tool member having a threaded box, a second member adapted to be connected to said threaded box, a retractable longitudinally split latch ring mounted on and movable laterally of said second member, said ring being provided with a male thread engageable with the box thread and having a downwardly diverging tapered inner surface, said ring being retractable on said second member to the extent in which the effective outer diameter-of said male thread is less than the inner diameter of said box thread, said second member being provided with an expander having a downwardly diverging tapered external surface eng-ageable with said tapered surface on said ring to urge said latch ring outwardly with its thread in engagement with said box thread, said ring being provided with cam means, coacting means on one of said members adapted to engage said cam means to retract said ring, whereby to disengage said male thread from said female thread upon relative longitudinal movement between said members, and a longitudinally extending key secured to said second member and slidably engaging said latch ring to provide a rotatable driving connection between said second member'and latch ring.

REUBEN C. BAKER.

References: Cited in the file of this patent UNITED STATES PATENTS Number Name Date v 808,378 Johnston Dec. 26,1905 1,367,156 McAlva'y et al. 1Feb. 1, 1921 1,593,909 Nixon July 2 7, 1926 2,228,243 Baker Jan. 14, 1941 2,378,469 Denton June 19; 1945 2,388,273 Lord Nov. 6, 1945 2,399,766 Steward May 7,1946