Liner hanger system

Information

  • Patent Grant
  • 6655456
  • Patent Number
    6,655,456
  • Date Filed
    Friday, August 31, 2001
    23 years ago
  • Date Issued
    Tuesday, December 2, 2003
    21 years ago
Abstract
There is disclosed a system in which a liner is lowered into and landed within an outer casing. The casing includes a casing joint having upwardly facing landing shoulders formed about its bore, and the liner has a recess thereabout which receives a “C” shaped hanger carried in a retracted position as it is lowered into the bore. The hanger has teeth about it which are arranged to seat upon the landing shoulders when the hanger is released to expand against the bore so that its teeth may be lowered onto the landing surface.
Description




This invention elates to a liner hanger system wherein a liner is to be suspended within an outer casing in the well bore as the liner is lowered into the outer casing for that purpose. As well known in the art, when the liner is so landed, it is cemented in place by means of cement pumped downwardly through and upwardly through the annulus between the casing, and then packed off within the outer casing.




A typical installation of this type, wherein the liner is suspended with the use of slips, is shown and described in Provisional Application No. 60/292,049, filed May 18, 2001, entitled Liner Hanger System, and assigned to the assignee of the present invention.




Other hangers for this purpose, i.e., hanging an inner casing within an outer casing, have locking elements adapted to be expanded into matching locking grooves formed in the outer casing. In some cases, the locking elements are adapted to be spring biased into matching grooves formed in the outer casing. However, these springs are susceptible to breaking or other malfunctions. This is especially true since the hanger often comprises a large number of intricate parts which are expensive to replace, and which require a delay in the overall well operations. In still other cases, the hangers having only a single latching part for fitting within a single groove, thus limiting its load carrying capacity.




The primary object of this invention is to provide a casing hanger system which overcomes these and other problems inherent in prior hangers for such systems.




These and other objects are accomplished, in accordance with the illustrated embodiment of this invention, by a liner hanger system comprising a joint of casing adapted to be connected as part of an outer casing installed within a wellborn, and a liner adapted to be lowered and landed within the outer casing. The bore of the casing joint has a polished bore and vertically spaced, upwardly facing landing surfaces formed therein, and the liner includes a tubular body having a recess formed about its body, and a hanger element comprising a circumferentially expandible and contractible C-ring disposed within the recess. The ring has teeth on its outer diameter for landing on the landing surfaces of the casing joint when in its expanded portion, and upon relative vertical movement with respect to the liner, is expanded outwardly against the polished bore. Upon continued relative movement of the liner and ring, the teeth will move into a position in which they expand further outwardly into landed positions on the landing surfaces to permit the liner to be suspended therefrom.











IN THE DRAWINGS





FIG. 1

is a vertical sectional view of the outer casing joint having its bore configured to cooperate with a hanger mounted on an inner casing or liner as it is lowered into the outer casing.





FIG. 2

is a view of the liner with the hanger mounted thereon for landing within the profiles in the outer casing;





FIG. 3

is a view similar to

FIG. 2

, but showing the liner and its hanger being lowered into the outer casing; and





FIG. 4

is another similar view, but with the liner lowered further to cause its hanger to engage with the profile in the outer casing, and then lowered to a position to lock the hanger in position.











With reference now to

FIG. 1

, the joint


10


of the outer casing section is threaded at its upper and lower ends to permit it to be connected as part of the outer casing installed in the well bore, as in the liner hanger system referred to in the aforementioned Provisional Application. The polished bore of the casing section has an annular recess


11


in its lower portion, and a series of vertically spaced, upwardly facing landing shoulders


12


above the recess


11


and separated therefrom by annular restriction


14


. There is another annular recess


15


formed in the bore above and separated from the landing surfaces


12


by means of an upper restriction


16


above an annular recess


13


. The restrictions and landing shoulder are of essentially the same diameter of the polished bore above them.




Hanger


17


is shown in

FIG. 2

to be carried within a recessed portion


18


about the liner L which, as previously described, may be for the purpose disclosed in the above noted Provisional Application. The hanger


17


is a C ring split about its circumference in position to be urged circumferentially outwardly from a normally contracted position to engage the inner diameter of the casing when expanded, but held in its contracted position, as shown, as the liner is run into the outer casing. In this position, its lower end


20


is adapted to be received within a groove


19


in the upper end of an enlarged outer diameter portion


21


of the liner.




The upper end of the hanger has teeth


22


formed thereabout in vertically spaced relation corresponding to the landing surfaces


12


of the casing and fitting within recess


18


about the liner. The toothed section and lower end of the ring are connected by an outwardly enlarged cylindrical portion


35


whose inner surface engages the outer surface of enlargement


25


about the liner.




As will be described and shown in

FIG. 3

, the hanger is adapted to be raised relative to the liner to release it for expansion outwardly into engagement with the polished bore of the outer casing. Thus, liner hanger system includes a suitable mechanism to raise the hanger out of its retained position, to free its lower end from groove


19


. As shown in the Provisional Application, this may be accomplished by raising the hanger by means of tie bars


30


connected at their upper ends to a cone C over which a packing element is adapted to be lowered to set it against the outer casing. The tie bars extend through vertical slots in the recessed portion of the liner, and have an outer flange


31


releasably connected in a groove


32


about a lower extension of the cone C.




Thus, it will be seen, from a comparison of FIG.


3


and

FIG. 4

, that raising of the packer cone will raise the lower end of the hanger free from the retaining groove


19


, and thus permit the hanger to expand outwardly to the position of FIG.


4


. This then permits rib


61


on the lower end of the tie bar to disengage from groove


62


in the lower end of the hanger and release the tie bars from the hanger as it moves into its upper relative position with respect to the liner. This relative vertical movement between the liner and packer element cone has resulted from shearing of pin


33


releasably connecting them in the position of FIG.


2


. This of course can be accomplished by raising of the packer cone relative to the liner, prior to lowering of the hanger into a position opposite the grooves forming landing surfaces in the bore of the outer casing.




Upon lowering of the hanger with the liner from the

FIG. 3

to the

FIG. 4

position, the lower radially enlarged section


35


of the hanger, which extends over the outer enlargement


25


of the liner, is free to move outwardly into the recess


11


in the outer casing. Thus, when lowered with the hanger to a position opposite the landing surfaces


12


within the outer casing, the lower end of the hanger is free from the groove about the liner, the teeth


22


about the upper end of the hanger are free to be expanded outwardly onto the landing surfaces, thus forming multiple shoulders on which to support the load of the liner within the outer casing. This outward expansion of the normally retracted hanger element has occurred after it has been lowered beneath the restriction


16


in the bore of the outer casing as the liner is lowered from its

FIG. 3

to its

FIG. 4

position.




Upon continued lowering of the liner, the hanger is expanded by enlargement


50


on the liner to force the hanger teeth


22


outwardly to maintain the hanger in its outer hanging position, as shown in

FIG. 4. A

downwardly facing shoulder


51


is formed on the outer diameter of the liner above the outward enlargement


50


so as to land on the upper end of the hanger, as shown in FIG.


4


. The outward enlargement is moved into the inner diameter of the hanger, as shown in

FIG. 4

, by virtue of a tapered shoulder formed on its upper end slidable over an inwardly and downwardly tapered shoulder surface on the hanger.




As the hanger is moved downwardly into landed position, enlargement


35


thereabout beneath its teeth fits closely within the recess


11


in the outer casing bore so as to limit outward expansion of the hanger element once it is moved into hanging position.




An inwardly enlarged portion


60


on the lower end of the hanger, beneath its outwardly enlarged portion


35


moves over the outer diameter of the lower end of the liner, thereby cooperating with the enlargement


50


to maintain the hanger element in its outer hanging position.



Claims
  • 1. A liner hanger system, comprisinga joint of casing adapted to be connected as part of an outer casing installed within a wellbore, a liner adapted to be lowered within the outer casing, the bore of said casing joint having vertically spaced, upwardly facing upper and lower landing surfaces formed on an intermediate portion thereof, and a lower annular recess separated from the lower landing surface by a lower annular restriction, the said liner including a tubular body having a recess formed thereabout with an annular groove formed in its lower end, a hanger comprising a circumferentially expandible and contractible C-ring disposed within and closely about the liner recess when in its normally contracted portion, said C-ring having teeth formed thereabout for landing on the landing surfaces of the casing joint when in its expanded portion, and a lower end fitting within the groove when in its contracted portion to permit the liner to be lowered through the outer casing, said C-ring being expandable, upon relative vertical movement with respect to the liner, so as to release its lower end from the groove and thereby permit the ring to expand outwardly against the outer casing, whereby, upon continued relative movement of the liner and ring, the teeth will move into a position in which they expand outwardly into landed positions on the landing surfaces to permit the liner to be suspended therefrom, said liner having a downwardly facing shoulder for landing on the upper end of the C-ring when expanded and an outward enlargement beneath the shoulder to fit within the upper end of the ring so as to hold the ring expanded.
  • 2. As in claim 1, includingsaid part surrounding and vertically moveable with respect to the liner, and a tie bar guidably reciprocable within the liner recess radially inwardly of the ring and having its upper end connected, and said tie bar and C-ring having radially extending parts which connect the tie bar to the ring to raise the ring out of the groove and, when the ring is so raised, are released from one other to permit the liner to be lowered with respect to the ring.
  • 3. As in claim 2, whereinthe liner recess has a vertical slot to receive the tie bar and a stop surface on its lower end to be engaged with the lower end of this tie bar prior to its being raised to lift the lower end of the ring from the groove in liner recess.
  • 4. As in claim 1, whereinthe bore of the casing joint also has an upper annular recess separated from the upper landing surface by an upper annular restriction.
  • 5. As in claim 1, whereinthe liner also has a lower outward enlargement thereabout above the groove for disposal within the lower end of the expanded ring.
  • 6. As in claim 1, whereinthe bore of the casing joint has a polished bore above the landing surface.
Parent Case Info

This application claims the benefit of provisional application No. 60/292,049, filed May 18, 2001.

US Referenced Citations (12)
Number Name Date Kind
3420308 Putch Jan 1969 A
3818987 Ellis Jun 1974 A
3893717 Nelson Jul 1975 A
3946807 Amancharla et al. Mar 1976 A
3999604 Amancharla et al. Dec 1976 A
4051896 Amancharla et al. Oct 1977 A
4281711 Braddick et al. Aug 1981 A
4311194 White Jan 1982 A
4468055 Reimert Aug 1984 A
5026097 Reimert Jun 1991 A
5586601 Pringle Dec 1996 A
5857524 Harris et al. Jan 1999 A
Non-Patent Literature Citations (1)
Entry
Otis Composite Catalog, “Liner Hanger Equipment and Services”, (1986-1987).
Provisional Applications (1)
Number Date Country
60/292049 May 2001 US