U.S. patent number RE46,241 [Application Number 14/226,275] was granted by the patent office on 2016-12-20 for wellhead completion assembly capable of versatile arrangements.
This patent grant is currently assigned to Weatherford Technology Holdings, LLC. The grantee listed for this patent is Weatherford/Lamb, Inc.. Invention is credited to Gordon Ronnie Altman, Michael L. Bilyeu, Brandon Matthew Cain, Carl Edwin Davidson, Robert Scott Menard, John Rogers, Todd Travis, Steve Willard.
United States Patent |
RE46,241 |
Cain , et al. |
December 20, 2016 |
Wellhead completion assembly capable of versatile arrangements
Abstract
A wellhead completion assembly has a head connected to surface
casing. A rotatable flange or the like can be used to connect
various components to a threaded end of the head. A casing hanger
installs in the head, and the hanger's upper end extends beyond the
head's top edge. This exposed end has an external threaded
connection to connect to various wellhead components using a
rotatable flange or the like. For example, a locking ring can
threadably connect to the head's threaded end to support the hanger
in the head. Then, a rotatable flange can threadably connect to the
hanger's exposed end so that another component, such as a
completion spool or gate valve, can nippled up directly to the
hanger. When the hanger is fluted, a pack-off assembly can allow
testing off inner and outer sealing integrity via a test port
accessible through an opening in the locking ring.
Inventors: |
Cain; Brandon Matthew (Houston,
TX), Travis; Todd (Humble, TX), Bilyeu; Michael L.
(The Woodlands, TX), Altman; Gordon Ronnie (Spring, TX),
Willard; Steve (Corpus Christi, TX), Davidson; Carl
Edwin (Humble, TX), Rogers; John (Grand Junction,
CO), Menard; Robert Scott (Houston, TX) |
Applicant: |
Name |
City |
State |
Country |
Type |
Weatherford/Lamb, Inc. |
Houston |
TX |
US |
|
|
Assignee: |
Weatherford Technology Holdings,
LLC (Houston, TX)
|
Family
ID: |
1000001612019 |
Appl.
No.: |
14/226,275 |
Filed: |
March 26, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
Reissue of: |
11925498 |
Oct 26, 2007 |
7779921 |
Aug 24, 2010 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
E21B
33/03 (20130101); E21B 17/02 (20130101); E21B
33/04 (20130101); E21B 17/08 (20130101); E21B
33/0415 (20130101); E21B 17/085 (20130101); E21B
33/03 (20130101); Y10T 29/49826 (20150115) |
Current International
Class: |
E21B
19/00 (20060101); E21B 17/08 (20060101); E21B
17/02 (20060101); E21B 33/03 (20060101); E21B
33/04 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Other References
Wood Group, "Special Products: Independent Wellhead System (IWS),"
Product Brochure, dated Apr. 2007, 2-pgs. cited by applicant .
Datta, Indrajit, FMC Technologies Canada, "DTO Time-Saving
Conventional Wellhead," Canadian Association of Drilling Engineers
eNews, obtained from
http://www.cade.ca/news.php?m=2006.sub.--12.sub.--A1, Dec. 2006,
4-pgs. cited by applicant .
FMC Technologies, "Isolation Sleeve Technology," obtained from
http://www.fmctechnologies.com/, generated Jun. 8, 2007, 1-pg.
cited by applicant .
FMC Technologies, "DTO Wellhead," obtained from
http://www.fmctechnologies.com/, generated Jun. 8, 2007, 5-pgs.
cited by applicant .
Canadian Assocation of Drilling Engineers, December Luncheon,
obtained from http://www.cade.ca/, 8-pgs. cited by applicant .
FMC Technologies, "FMC Surface Wellhead Catalog," copyrighted 2004,
pp. 1, 57, & 106. cited by applicant.
|
Primary Examiner: Dawson; Glenn K
Attorney, Agent or Firm: Blank Rome, LLP
Claims
What is claimed is:
1. wellhead completion assembly, comprising: a casing head
connecting to casing at a wellhead and having a first external
threaded connection adjacent a first end; a casing hanger landing
in the casing head and having a shoulder and a second end, the
second end extending beyond the first end of the casing head and
having a second external threaded connection, the second external
threaded connection connectable to a connector to support at least
one additional component above the casing hanger; a pack-off plate
disposed on the second end of the casing hanger adjacent the
shoulder, the pack-off plate having an upper surface, an inner
portion, and an outer portion, the inner portion .[.sealable.].
.Iadd.sealably .Iaddend.engaging an external surface of the casing
hanger, the outer portion .[.sealable.]. .Iadd.sealably
.Iaddend.engaging an internal surface of the casing head; and a
head ring threadably connecting to the first external threaded
connection of the casing head and defining an opening through which
the second end of the casing hanger extends, a portion of the head
ring directly engaging the upper surface of the pack-off plate.
2. The assembly of claim 1, wherein the pack-off plate comprises: a
first pair of sealing seats on the outer portion, a second pair of
sealing seats on the inner portion, and a test port defined in the
upper surface and accessible through the opening in the head ring,
the test port communicating with the inner and outer portions
between the first and second pairs of sealing seats.
3. The assembly of claim 1, wherein the casing head comprises a
single-bowl arrangement defining an internal shoulder within an
internal bore, the casing hanger landing on the internal shoulder
to be supported therein.
4. The assembly of claim 1, wherein the casing head comprises a
double-bowl arrangement defining an internal shoulder within an
internal bore, the casing hanger landing on one or more components
supported by the internal shoulder.
5. The assembly of claim 1, wherein the casing hanger defines at
least one flute, and wherein the pack-off .[.plates.]. .Iadd.plate
.Iaddend.seals fluid communication through the at least one
flute.
6. The assembly of claim 1, further comprising a hanger ring
positionable about the external surface of the casing hanger, and
wherein the pack-off plate comprise a lip positionable in wedged
engagement between the hanger ring and a portion of the external
surface of the casing hanger.
7. The assembly of claim 4, wherein the casing head for the
double-bowl arrangement comprises at least two head components
interconnectable to one another, a first of the head components
having the internal shoulder therein, a second of the head
components having the first external threaded connection to which
the head ring threadably connects.
8. The assembly of claim 6, wherein the inner portion of the
pack-off plate threadably connects to a third threaded connection
on the external surface of the casing hanger.
9. A wellhead completion assembly, comprising: a casing head
connecting to a first casing and having a first external threaded
connection adjacent a first end, the casing head comprising a
double-bowl arrangement defining an internal shoulder within an
internal bore; a casing hanger landing on one or more other
components supported by the internal shoulder of the casing head,
the casing hanger defining at least one flute and having a shoulder
and a second end, the second end extending beyond the first end of
the casing head and having a second external threaded connection,
the second external threaded connection connectable to a connector
to support at least one additional component above the casing
hanger; a head ring threadably connecting to the first external
threaded connection of the casing head and defining an opening
through which the second end of the casing hanger extends; and at
least one pack-off component .[.positioning.]. .Iadd.positioned
.Iaddend.between the shoulder of the casing hanger and a portion of
the head ring, the at least one pack-off component sealably
engaging an external surface of the casing hanger and sealably
engaging an internal surface of the casing head, the at least one
pack-off component sealing fluid communication through the at least
one flute in the casing hanger.
10. The assembly of claim 9, wherein the casing head for the
double-bowl arrangement comprises at least two head components
interconnectable to one another, a first of the head components
having the internal shoulder therein, a second of the head
components having the first external threaded connection to which
the head ring threadably connects.
11. The assembly of claim 9, wherein the at least one pack-off
component comprises a pack-off plate having-- an inner portion
threadably connecting to a third threaded connection on the
external surface of the casing hanger, and an outer portion
sealably engaging the internal surface of the casing head.
12. The assembly of claim 11, wherein the at least one pack-off
component comprises a hanger ring positionable about the external
surface of the casing hanger, and wherein the pack-off plate
comprise a lip positionable in wedged engagement between the hanger
ring and a portion of the external surface of the casing
hanger.
13. The assembly of claim 9, wherein the at least one pack-off
component comprises a pack-off plate having-- a first pair of
sealing seats on an outer portion, a second pair of .[.seals.].
.Iadd.sealing seats .Iaddend.on an inner portion, and a test port
defined in an upper surface of the plate and accessible through the
opening in the head ring, the test port communicating with the
outer portion between the first pair of sealing seats and
communicating with the inner portion between the second pair of
sealing seats.
14. A .Iadd.system for a .Iaddend.wellhead completion assembly,
comprising: a first head component having one end connectable to
casing at a wellhead and having a first external threaded
connection adjacent another end; and second head components each
having .[.second.]. .Iadd.an .Iaddend.internal threaded
.[.connections.]. .Iadd.connection .Iaddend.adjacent one end and
having .Iadd.a .Iaddend.second external threaded .[.connections.].
.Iadd.connection .Iaddend.adjacent another end, .[.the second.].
.Iadd.each .Iaddend.internal threaded connection connectable to the
first external threaded connection on the first head component, the
.[.second.]. internal and external threaded connections of
.Iadd.each of .Iaddend.the second head components being
complementary and threadably interconnectable to one another,
wherein the first head component is Used independently on the
wellhead for a single-bowl arrangement of the wellhead completion
assembly, wherein one of the second head components is used in
conjunction with the first head component for a first multiple-bowl
arrangement of the wellhead completion assembly, the .[.second.].
internal threaded connection of the one second head component
connecting to the first external threaded connection on the first
head component to stack the one second head component on top of the
first head component; and wherein two or more of the second head
components are used in conjunction with the first head component
for second multiple-bowl arrangements of the wellhead completion
assembly, the .[.second.]. internal and external threaded
connections of the second head components interconnecting to one
another to stack the two or more second head components on top of
one another, the internal threaded connection of a lowermost one of
the second head components connecting to the first external
threaded connection on the first head component to stack the second
head components on top of the first head component.
15. The .Iadd.system for the .Iaddend.assembly of claim 14, further
comprising: a casing hanger .[.supported.]. .Iadd.supportable
.Iaddend.in the wellhead completion assembly, the casing hanger
having a distal end extending beyond .Iadd.the first head component
in the single-bowl arrangement or beyond .Iaddend.a topmost
.[.end.]. .Iadd.one of the second head components in the
multiple-bowl arrangements .Iaddend.of the wellhead completion
assembly, the distal end having an external threaded connection
connectable to a connector to support at least one additional
component above the casing hanger; and a head ring threadably
connectable to the first external threaded connection on the first
head component in the single-bowl arrangement or threadably
connectable to the second external connection of a topmost one of
the second head components in the .[.multi-bowl arrangement.].
.Iadd.multiple-bowl arrangements.Iaddend., the head ring defining
an opening through which the distal end of the casing hanger
extends.
16. The .Iadd.system for the .Iaddend.assembly of claim 15, wherein
a portion of the head ring directly engages a shoulder of the
casing hanger, and wherein the casing hanger comprises-- a pair of
sealing seats on an outer surface, and a test port defined in the
shoulder and accessible through the opening in the head ring, the
test port communicating between the pair of sealing seats.
17. The .Iadd.system for the .Iaddend.assembly of claim 15, further
comprising a pack-off plate disposed in the topmost .[.end.].
.Iadd.one .Iaddend.of the .[.wellhead completion assembly.].
.Iadd.head components .Iaddend.between the casing hanger and a
portion of the head ring, wherein the pack-off plate comprises: an
upper surface positioning adjacent the portion of the head ring; an
inner portion engaging an external surface of the casing hanger,
and an outer portion engaging an internal surface of the wellhead
completion assembly.
18. The .Iadd.system for the .Iaddend.assembly of claim 17, wherein
the pack-off plate comprises: a first pair of sealing seats on the
outer portion, a second pair of sealing seats on the inner portion,
and a test port defined in the upper surface and accessible through
the opening in the head ring, the test port communicating with the
inner and outer portions between the first and second pairs of
sealing seats.
19. The .Iadd.system for the .Iaddend.assembly of claim 14, further
comprising: a hub threading on the first external threaded
connection of the first head component in the single-bowl
arrangement or threading on the second external threaded connection
of the topmost one of the second head components in the
.[.multi-bowl.]. .Iadd.multiple-bowl .Iaddend.arrangements; and an
adapter .[.disposing.]. .Iadd.disposed .Iaddend.on .[.the.].
.Iadd.an .Iaddend.end of .Iadd.one .Iaddend.the first or second
head .[.component.]. .Iadd.components .Iaddend.and locking to the
hub, the adapter .[.connecting.]. .Iadd.connectable .Iaddend.to at
least one additional component above the wellhead assembly.
20. The .Iadd.system for the .Iaddend.assembly of claim 14, wherein
in the first and second multiple-bowl arrangements, the .[.one or
more.]. second head components are removable from the first head
component to expose an end of a stuck pipe in the wellhead
completion assembly; and wherein a rotatable flange connects to the
first external threaded connections of the first head component to
support one or more additional components above the first head
component.
21. A hanger pack-off assembly, comprising: a casing hanger
positionable in a casing head and having a first external threaded
connection about an external surface; a hanger ring positionable
about the external surface of the casing hanger; and a pack-off
plate defining .[.an.]. .Iadd.a first .Iaddend.opening through
first and second sides of the plate, the .Iadd.first
.Iaddend.opening having a first internal threaded connection
threading onto the first external threaded connection on the casing
hanger, an outer surface of the plate having a first pair of
sealing seats formed thereabout, an inner surface of the plate
having a second pair of sealing seats formed thereabout, a test
port defined in the first side of the plate and communicating with
the inner and outer surfaces between the first and second pairs of
sealing seats, the pack-off plate comprising a lip positionable in
wedged engagement between the hanger ring and a portion of the
external surface of the casing hanger.
22. The assembly of claim 21, further comprising a head ring
threadably .[.connecting.]. .Iadd.connectable .Iaddend.to the
casing head and defining .[.an.]. .Iadd.a second .Iaddend.opening
therethrough, wherein the casing hanger has a distal end extending
through the .Iadd.second .Iaddend.opening, the distal end having a
second external threaded connection to which a component connects
to the casing hanger.
23. A wellhead completion method, comprising: connecting a casing
head to surface casing; landing a casing hanger in the casing head
to support production casing in the surface casing such that an
upper end of the casing hanger extends beyond an upper end of the
casing head; disposing a pack-off plate on the upper end of the
casing hanger, the pack-off plate sealably engaging an external
surface of the casing hanger and sealably engaging an internal
surface of the casing head; threadably connecting a head ring on
the upper end of the casing head and directly engaging an upper
surface of the pack-off plate with the head ring, the upper end of
the casing head fitting through an opening of the head ring;
threading a connector to the upper end of the casing hanger; and
connecting an additional component above the casing hanger by
connecting to the connector.
24. The method of claim 23, wherein disposing the pack-off plate on
the upper end of the casing hanger comprises threading an inside
portion of the pack-off plate on external .[.thread.].
.Iadd.threads .Iaddend.on the upper end of the casing hanger.
25. The method of claim 23, wherein disposing the pack-off plate on
the upper end of the casing hanger comprises sealing an inner pair
of seals on the pack-off plate against the external surface of the
casing hanger and sealing an outer pair of seals on the pack-off
plate against the internal surface of the casing head.
26. The method of claim 25, further comprising testing the inner
and outer pairs of seals via a test port defined in the upper
surface of the pack-off plate and accessible through the opening in
the head ring.
27. The method of claim 23, wherein disposing the pack-off plate on
the upper end of the casing hanger comprises: wedging a lip on the
pack-off plate between a hanger ring and the external surface of
the casing hanger, and engaging the hanger ring against the
internal surface of the casing head.
28. The method of claim 23, wherein threading the connector to the
upper end of the casing hanger comprises threading a rotatable
flange to the upper end of the casing hanger.
29. The method of claim 28, wherein connecting the additional
component above the casing hanger comprises connecting a gate valve
for a facing operation to the rotatable flange.
30. The method of claim 23, wherein before threadably connecting
the head ring, threading the connector to the upper end of the
casing hanger, and connecting the additional component above the
casing hanger, the method comprises initially removing a blow out
preventer stack and a first rotatable flange from the casing head,
the first rotatable flange being threaded on an external thread on
the casing head.
31. The method of claim 30, wherein the first rotatable flange is
rated for a first working pressure, and wherein the connector
threading to the upper end of the casing hanger comprises a second
rotatable flange having a second working pressure greater than the
first working pressure.
32. The method of claim 23, wherein landing the casing hanger
comprises passing the casing hanger on a running tool through a
blow out preventer stack installed on the casing head.
33. A wellhead completion assembly, comprising: a casing head
connecting to casing at a wellhead and having a first external
threaded connection adjacent a first end; a casing hanger landing
in the casing head and having a second end and a shoulder, the
casing hanger comprising a pair of sealing seats on an outer
surface and comprising a test port defined in the shoulder, the
test port communicating between the pair of sealing seats, the
second end extending beyond the first end of the casing head and
having a second external threaded connection, the second external
threaded connection connectable to a connector to support at least
one additional component above the casing hanger; and a head ring
threadably connecting to the first external threaded connection of
the casing head and defining an opening through which the second
end of the casing hanger extends, a portion of the head ring
directly engaging the shoulder on the casing hanger, the test port
in the shoulder of the casing hanger being accessible through the
opening in the head ring.
34. The assembly of claim 33, wherein the casing head comprises a
single-bowl arrangement defining an internal shoulder within an
internal bore, the casing hanger landing on the internal shoulder
to be supported therein.
35. The assembly of claim 33, wherein the casing head comprises a
double-bowl arrangement defining an internal shoulder within an
internal bore, the casing hanger landing on one or more components
supported by the internal shoulder.
36. The assembly of claim 35, wherein the casing head for the
double-bowl arrangement comprises .[.and.]. .Iadd.at .Iaddend.least
two head components interconnectable to one another, a first of the
head components having the internal shoulder therein, a second of
the head components having the first external threaded connection
to which the head ring threadably connects.
37. A wellhead completion assembly, comprising: a casing head
connecting to a first casing and having a first external threaded
connection adjacent a first end, the casing head comprising a
double-bowl arrangement defining an internal shoulder within an
internal bore; a casing hanger landing on one or more other
components supported by the internal shoulder of the casing head,
the casing hanger having a shoulder and a second end, the second
end extending beyond the first end of the casing head and having a
second external threaded connection, the second external threaded
connection connectable to a connector to support at least one
additional component above the casing hanger; a head ring
threadably connecting to the first external threaded connection of
the casing head and defining an opening through which the second
end of the casing hanger extends; a hanger ring positionable about
an external surface of the casing hanger; and a pack-off plate
.[.positioning.]. .Iadd.positioned .Iaddend.between the shoulder of
the casing hanger and a portion of the head ring, the pack-off
plate having an inner portion threadably connecting to a third
threaded connection on the external surface of the casing hanger,
the pack-off plate having an outer portion sealably engaging an
internal surface of the casing head, the pack-off plate comprising
a lip positionable in wedged engagement between the hanger ring and
a portion of the external surface of the casing hanger.
38. The assembly of claim 37, wherein the casing head for the
double-bowl arrangement comprises .[.and.]. .Iadd.at .Iaddend.least
two head components interconnectable to one another, a first of the
head components having the internal shoulder therein, a second of
the head components having the first external threaded connection
to which the head ring threadably connects.
39. The assembly of claim 37, wherein the casing hanger defines at
least one flute, and wherein the .[.at least one.]. pack-off plate
seals fluid communication through the at least one flute.
40. The assembly of claim 37, wherein the pack-off plate
comprises-- a first pair of sealing seats on the outer portion, a
second pair of .[.seals.]. .Iadd.sealing seats .Iaddend.on the
inner portion, and a test port defined in an upper surface of the
plate and accessible through the opening in the head ring, the test
port communicating with the outer portion between the first pair of
sealing seats and communicating with the inner portion between the
second pair of sealing seats.
Description
BACKGROUND
A well has one or more casings installed in a borehole to reinforce
and seal it, and wellhead components install at the surface above
the exposed end of the casings. For example, FIG. 1 shows a
wellhead arrangement according to the prior art. Typically, an
outermost conductor pipe is driven into place in the borehole, and
a base assembly 11 is on the exposed end of conductor pipe 10. A
casing head 30 lands on the base assembly 11 and connects to a
surface casing 14 supported inside the conductor pipe 10.
Typically, the space between the casing 14 and pipe 10 is filled
with cement. One or more adapters 40 and components 50 of a
blow-out preventer can connect above the casing head 30. As shown
in FIG. 1, flanged connections are typically used to connect the
various components together.
Because various operations may be performed at the wellhead, the
arrangement of components may be modified to accommodate different
operations, pressures, and implementations. One typical wellhead
operation involves fracing. According to conventional practices, an
isolation tool, such as a stinger, installs in the wellhead to
isolate bores and outlets from pressures that may be higher than
pressure-ratings for the wellhead's flange connections.
In one typical wellhead arrangement, a casing hanger supports
casing in the casing head, and a tubing spool nipples to the casing
head so that another hanger can be used in the tubing spool to
support tubing in the casing. Typically, an adapter must be
installed on the casing head prior to nippling up the tubing spool
so that the adapter can pack-off or seal around the casing hanger.
In another typical wellhead arrangement, a fluted casing hanger
support casing in the casing head so that drilling fluids during
cementing operations are allowed to return through the hanger's
flutes. Later, a pack-off bushing installs above the fluted casing
hanger to seal off the flutes. Typically, there is only a limited
ability to test the seal created by such a pack-off.
SUMMARY
A wellhead completion assembly is capable of versatile
arrangements. The assembly has a first head component that connects
to surface casing. A rotatable flange or the like can be used to
connect various components to a threaded end of this first head
component. Alternatively, second head components can threadably
stack on top of one another and can threadably stack on top of the
first head component to create a multi-bowl arrangement.
For either arrangement, the assembly can use a casing hanger that
installs in the head (i.e., first head component in a single-bowl
arrangement or the top most second head component in a multi-bowl
arrangement). In either case, the hanger's upper end extends beyond
the head's top edge. This exposed end has an external threaded
connection to connect to various wellhead components using a
rotatable flange or the like. For example, a locking ring can
threadably connect to the head's threaded end to support the casing
hanger in the head. Then, a rotatable flange can threadably connect
to the hanger's exposed end so that another component, such as a
completion spool or gate valve, can nippled up directly to the
casing hanger.
The casing hanger can be fluted or not, and a pack-off plate can be
used to seal the casing hanger in the head. This pack-off plate can
have a test port accessible through an opening in the locking ring
holding the hanger in the head. The test port allows operators to
test the inner and outer sealing integrity of the pack-off plate.
In one particular arrangement, the casing hanger has a sealing ring
positioned about its external surface. The pack-off plate threads
onto an external threaded connection on the casing hanger, and a
lip on the pack-off plate positions in wedged engagement between
the sealing ring and a portion of the external surface of the
casing hanger.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partial cross-sectional view illustrating a wellhead
arrangement according to the prior art.
FIG. 2 is a cross-sectional view illustrating a wellhead completion
assembly in one arrangement having portion of a Blow-Out Preventer
(BOP) stack nippled up to a casing head.
FIG. 3A is a cross-sectional view illustrating the assembly of FIG.
2 in another arrangement having a completion spool nippled up to
the casing hanger.
FIG. 3B is a detail illustrating portions of the casing hanger, the
locking ring, and the casing head of FIG. 3A.
FIG. 4 is a cross-sectional view illustrating the assembly of FIG.
2 in yet another arrangement having a gate valve nippled up to the
casing hanger.
FIGS. 5A-5B are top and cross-sectional views illustrating a fluted
casing hanger for the disclosed assembly.
FIG. 6 is a cross-sectional view illustrating a pack-off plate.
FIG. 7A is a partial cross-sectional view illustrating a flange and
the pack-off components on the fluted casing hanger of FIGS.
5A-5B.
FIG. 7B is a detail of FIG. 7A illustrating features of the
pack-off components.
FIG. 8 is a cross-sectional view illustrating the casing head of
FIG. 2 landed through a riser.
FIGS. 9A-9B are cross-sectional views illustrating the casing head
of FIG. 2 used with other wellhead components.
FIG. 10A is a cross-sectional view illustrating another embodiment
of a wellhead completion assembly in one arrangement.
FIG. 10B is a cross-sectional view illustrating the assembly of
FIG. 10A in another arrangement.
FIGS. 11A-11.[.D.]..Iadd.E .Iaddend.are cross-sectional views
illustrating a wellhead completion assembly having modular head
components in various stages of assembly.
FIGS. 12A-12B are cross-sectional views illustrating the modular
assembly using only a first head component.
FIG. 13 is a cross-sectional view illustrating the modular assembly
using three head components.
FIGS. 14A-14C are cross-sectional views illustrating the modular
assembly when stuck pipe occurs.
FIGS. 15A-15C are cross-sectional views illustrating the modular
assembly having a control line when stuck pipe occurs.
DETAILED DESCRIPTION
A versatile wellhead completion assembly is capable of various
arrangements. The assembly includes a casing head that lands on a
conductor pipe and connects to surface casing. The head's upper end
has an external threaded connection to which various components can
be connected depending on the desired arrangement. For example, a
rotatable flange or other connector can thread onto the head's
upper end, and a component of a blow-out preventer (BOP) can bolt
to the rotatable flange above the casing head.
The assembly also includes a casing hanger that lands in the casing
head to support production casing within the surface casing. When
installed in the head, the hanger's upper end extends beyond the
head's top edge. This exposed end has an external threaded
connection that allows various components to connect to the
hanger's upper end depending on the desired arrangement. For
example, a locking ring can threadably connect to the head's
external threaded connection to support the casing hanger in the
casing head. Then, a rotatable flange or other connector can
threadably connect to the hanger's exposed end so that a completion
spool, gate valve, or other wellhead component can bolt to the
rotatable flange above the casing hanger.
In other arrangements, the casing head can be used with
conventional wellhead components and can be landed through a riser
using a running tool threaded to internal threads in the casing
head. In addition, the casing hanger used in the various
arrangements can be fluted, and a pack-off assembly that allows
testing a inner and outer seals can be used with the fluted casing
hanger. In still other arrangements, modular head components of the
assembly permit operators to make various arrangements of the head
components to suit their needs in either single-bowl or
multiple-bowl arrangements and to facilitate contingency operations
in the event a stuck pipe occurs.
Turning now to the drawings, FIG. 2 illustrates a well completion
assembly having a casing head 100 and a casing hanger 200. The
casing head 100 with a landing ring 22 attached thereto lands on a
support ring 20 on an exposed end of conductor pipe 10, and an
internal threaded connection 104 connects to surface casing 12.
Side ports 102 for valves or the like are provided in the head's
bore 101 for various uses during well operations. When the casing
head 100 is installed as shown, flutes (not shown) in the rings
20/22 can allow cement to be inserted between the conductor pipe 10
and the surface casing 12 during a cementing job.
In the arrangement, a rotatable flange 110 threadably connects to
an external threaded connection 106 on the casing head's upper end
.Iadd.103a.Iaddend., and a BOP stack component 50 nipples up to the
casing head 100 by bolting to the flange 110. To seal this
connection, a gasket is disposed in a groove at head's top edge.
Rather than using the rotatable flange 110 as shown, a drilling
adapter, such as element 530 shown in FIG. 10A, or other connector
could alternatively be used.
Also in the arrangement, the casing hanger 200 has production
casing 14 connected by an internal threaded connection 204 at the
hanger's lower end .Iadd.203b.Iaddend.. To install the hanger 200
and the casing 14, a running tool 52 connects by a coupling 54 to
an external threaded connection 206 at the hanger's upper end
.Iadd.203a.Iaddend., and the hanger 200 and the casing 14 are run
through the BOP stack component 50 and into the casing head 100.
Once run in, the casing hanger 200 lands in the head 10 by engaging
an internal shoulder 103 so that the production casing 14 is
supported within the surface casing 12.
As will be appreciated, each of the components of the assembly is
composed of a suitable material known in the art for a wellhead
component. Preferably, the threaded connections (106, 204, and 206)
have ACME-2G left-handed thread forms. For some exemplary
dimensions, the conductor pipe 10 may be 16-in. casing, and the
surface and production casings 12/14 may respectively be 95/8-in.
and 41/2-in. casings. The connection of the rotatable flange 110 to
the BOP stack component 50 may be 11-in. rated at a working
pressure of 5,000-PSI. As one skilled in the art will appreciate,
these values are provided as examples for illustrative purposes,
and components of the assembly can be sized for 13-inch connections
and other sizes of casing.
During operations, it would be desirable to be able to nipple up a
tubing spool above a production casing hanger without requiring the
use of secondary pack-off to seal around the hanger. As shown in
FIG. 3A, the disclosed assembly allows a completion spool 60 to
nipple up to the casing hanger 200 of the disclosed assembly
without the need for secondary pack-off. In this arrangement, a
locking ring or head ring 120 defining a central opening 122
installs over the hanger's end .Iadd.203a .Iaddend.exposed above
the head 100, and internal threads on the ring's sides 126 couple
to the external threaded connection 106 on the casing head 100.
This connection 106 can be 11-in. rated at a working pressure of
10,000-PSI. As shown in the detail of FIG. 3B, the ring's inside
surface 124 engages the hanger's upper shoulder 207 to hold the
hanger 100 in the head 100. Also, the inside surface 122 engages a
gasket 108 disposed in a groove at the head's top edge.
With the ring 120 installed, the tubing spool 60 call couple
directly to the exposed end .Iadd.203a .Iaddend.of the hanger 200.
In particular, a rotatable flange 62 or other connector threads
onto the hanger's external threaded connection 206, and the spool
60 bolts to the rotatable flange 62. A gasket is disposed in a
groove at the hanger's top edge to seal the connection. This
connection between hanger 200 and spool 60 can be 4 1/16-in. rated
at a working pressure of 10,000-PSI, for example. With the spool 60
connected, other components can then be connected above the spool
60, and tubing (not shown) can eventually be hung in the spool's
bowl using a tubing hanger (not shown). Because the completion
spool 60 nipples up directly to the hanger 200, the casing hanger
200 essentially acts as a spool, and the need for secondary
pack-off is eliminated.
As shown in detail in FIG. 3B, the hanger's upper shoulder 207
defines a test port 208 that communicates between two sealing seats
209 disposed about the hanger's outer cylindrical surface. With the
hanger 200 installed in the head's internal bore 101 as shown, this
test port 208 is accessible through the ring's opening 122 so that
the seal formed between the sealing seats 209 and the casing head's
internal bore 101 can be tested.
FIG. 4 shows a similar arrangement with a gate valve 65 nipple up
to the casing hanger 200 of the assembly. Again, the rotatable
flange 62 couples to the external threaded connection 206 on the
exposed end .Iadd.203a .Iaddend.of the hanger 200, and the gate
valve 65 bolts to the flange 62. As will be appreciated, the gate
valve 65 may be used for facing operations or the like. With
respect to frac operations, it would be desirable to be able to
frac at high pressures without needing to use an isolation tool in
the wellhead. In current arrangement of the disclosed assembly,
there is no need to use an isolation tool (or a nipple up/down
apparatus for such an operation). Rather, interior frac pressures
can reach as high as the internal yield pressure of the production
casing 14 itself because the housing of the casing 14 communicates
directly with the gate valve 65 through the casing hanger 200.
Therefore, frac pressures that can be used with the disclosed
assembly are not limited by conventional flange pressure ratings of
adapters or the like that would typically be used above a
production casing hanger.
The hanger 200 shown in FIG. 4 has flutes that allow fluid returns
past the hanger 200 when used in some arrangements. In FIG. 4,
however, a pack-off assembly 210 having a pack-off plate and other
components forms a seal between the fluted hanger 200 and the
inside surface of locking ring or head ring 120. When this form of
pack-off is done, it is desirable to have an adequate and
convenient way to test the pack-off's inner and outer seals. In the
prior art, however, the only way to test the integrity of a
pack-off's seals requires operators to nipple up the next spool
above the pack-off assembly and to then perform a flange pressure
test. For example, FIG. 9A discussed below shows a conventional
pack-off plate 74 having an inner seal that engages casing 14 and
having an outer seal that engages casing head 100. To test the
seals, a tubing spool 70 must be rippled up to the casing head 100,
and a flange pressure test must be performed using a test port 73
on the spool 70. If the test fails, operators have to nipple down
the spool 70 and pull out the pack-off plate 74 to investigate the
cause. This procedure can be time intensive.
In contrast, the pack-off assembly 210 in FIG. 4 has a top-access
test port 212 accessible through the sealing ring's opening 122.
This test port 212 communicates between two sets of inner and outer
seals on the assembly 210. In this way, the sealing integrity of
the assembly's inner and outer seals can be tested simultaneously
and as soon as the assembly 210 is installed so that time can be
saved on site. Further details of a fluted hanger and a pack-off
assembly are discussed below with reference to FIGS. 5A through
8C.
FIGS. 5A-5B illustrate a fluted casing hanger 300 for use with the
disclosed assembly in top and cross-sectional views, respectively.
As with other hangers disclosed herein, the fluted hanger 300 has
an internal bore 302 with an internal threaded connection 303 at
its lower end .Iadd.303b .Iaddend.to connect to production casing
(not shown). In addition, the hanger's upper end .Iadd.303a
.Iaddend.has an external threaded connection 306 for coupling to
running tool as in FIG. 2 or to a rotatable flange as in FIG. 3A.
Furthermore, the hanger's top edge defines an annular well 308 for
a gasket (not shown) used to seal engagement between the hanger 300
and the various other components discussed herein.
Being fluted, however, the hanger's lower end .Iadd.303b
.Iaddend.defines a plurality of flutes or cutaways 304 (four shown
in FIG. 5A) that enable fluid returns to communicate past the
hanger 300. In another distinction, the hanger 300 as shown in FIG.
5B has a blunt or flat lower end .Iadd.305 .Iaddend.as opposed to
the substantially extended and narrowed lower end .Iadd.(e.g., 214:
FIG. 4) .Iaddend.of the other hangers disclosed herein. It will be
appreciated that any of the other hangers (either fluted or not)
disclosed herein may have a similar blunt end .Iadd.305 .Iaddend.if
desired.
As briefly discussed above in FIG. 4, a pack-off assembly 210 can
be used to seal communication through flutes of a fluted hanger
when returns are no longer desired. When used, the pack-off
assembly 210 preferably allows the sealing integrity of inner and
outer seals to be tested in an adequate and convenient way. For
such as a pack-off assembly, FIG. 6 illustrates a pack-off plate or
sealing ring 400 capable of such testing ability, and FIGS. 7A-7B
illustrate the pack-off plate 400 and an additional sealing ring or
hanger ring 430 positioned on the fluted casing hanger 300 of FIGS.
5A-5B.
As best shown in FIGS. 7A-7B, the sealing ring or hanger ring 430
positions adjacent a lowermost shoulder 309a on the hanger 300. The
pack-off plate 400 (shown in cross-section in FIG. 6) has a central
opening 402 and positions over the hanger's narrower end .Iadd.303a
.Iaddend.and threads its internal threads 407 onto intermediate
threaded connection 307 on the hanger 300. This pack-off plate 400
may be referred to as a production casing hanger pack-off or an
H-plate.
As the pack-off plate 400 is tightened onto the hanger 300,
internal seals 450 (e.g., O-rings) on the pack-off plate 400
eventually engage a side portion 309b of the hanger's surface,
while outer seals 440 (e.g., O-rings) engage the internal wall of
the casing head's bore (not shown). Likewise, the plate's lower lip
404 wedges in between the lowermost ring 430 and a side portion
309b of the hanger's surface so that the lower-most ring 430 seals
against the internal wall of the casing head's bore (not
shown).
To test the sealing integrity, the pack-off plate 400 defines a
test port 406 in its top surface 405 that is accessible when the
locking ring (e.g., 120 in FIG. 4) is used. As best shown in the
cross-section of the plate 400 in FIG. 6, the test port 406
communicates with spaces between the outer and inner seats 408/409
for the seals (440/450) so that their sealing integrity can be
tested. Because this test port 406 is accessible through the
locking ring's opening (122), this testing can be done during
partial assembly of the pack-off or after complete assembly of the
arrangement.
In addition to being used with the casing hanger 200, pack-off
assembly 210, and other components discussed above, the casing head
100 can be used on its own with various other wellhead components
in a number of other arrangements. In one example shown in FIG. 8,
the casing head 100 can be run through a riser 16 and landed on a
support ring 20 using an internal running tool 18. To run the head
100, the internal running tool 18 has a coupling 19 that attaches
to an internal threaded connection 107 in the casing head's bore
101.
In other uses, the casing head 100 can also be used on its own in
conjunction with some conventional wellhead components. For
example, FIG. 9A shows the casing head 110 having a completion
spool 70 nippled up to the head 100 with a rotatable flange 110.
FIG. 9B shows a similar arrangement, but in this example, a
completion spool 80 and adapter 82 nipple up to the casing head 100
with a rotatable flange 110.
In both arrangements, a conventional hanger 76 having slips 77
lands on the head's internal shoulder 103 to support the production
casing 14, and a conventional pack-off plate 74 seals against the
production casing 14 and the head 100. Segmented rings 72 engage
against the production casing 14 within the spool 70 in FIG. 9A,
while internal seals in the adapter 82 engage against the end of
production casing 14 in FIG. 9B.
The casing head 100 disclosed above represents a single-bowl type,
meaning that it defines a single bowl and has a length for
supporting a single hanger. FIGS. 10A-10B illustrates a wellhead
completion assembly having a casing head 500 that represents a
double-bowl type. Accordingly, one casing hanger 510 (FIG. 10A) or
two casing hangers 510/540 (FIG. 10B) can be used with this casing
head 500. Although shown as fluted, the casing hangers 510/540
could be mandrel hangers, if desired.
In the arrangement of FIG. 10A, a BOP stack component 50 nipples up
to the casing head 500. In this example, the connection uses a
drilling adapter 530 that has a locking assembly 532 for quick
connect to the casing head 500, pack-off screws 534 for other
purposes, and a flange 536 for bolting to the BOP stack component
50. The casing hanger 510 lands in the casing head 500 through the
BOP stack component 50 using a running tool (not shown). A pack off
assembly 520 having pack-off elements 522 installs above the casing
hanger 510, and pack-off screws 524 on the head 500 engage the
elements 522. Once installed, the pack-off assembly 520 forms an
additional bowl in the head 500. In this example, the conductor
pipe 10 can be 20-in. casing, and the surface casing 12 can be
95/8-in casing. The casing hanger 510 can support 7-in. production
casing.
In the arrangement of FIG. 10B, the casing hanger 510 and the
pack-off assembly 520 again install in the casing head 500
.Iadd.toward its lower end 503b.Iaddend., and a fluted hanger 540
.Iadd.with flutes on its lower end 543b .Iaddend.and .Iadd.a
.Iaddend.pack off assembly 545 install in the .Iadd.upper
.Iaddend.end .Iadd.503a .Iaddend.of the casing head 500. A locking
ring 550 threads onto the .Iadd.upper .Iaddend.end .Iadd.503a
.Iaddend.of the casing head 500 and engages the pack-off assembly
545, and a completion spool 560, gate valve, or other component
nipples up to the .Iadd.upper .Iaddend.end .Iadd.543a .Iaddend.of
the fluted hanger 540 with a rotatable flange 562 or other
connector. In this example, the first hanger 510 can support 7-in.
production casing 14, while the second hanger 540 can support
4.5-in. casing 15.
In addition to these arrangements of FIGS. 10A-10B, the double-bowl
type casing head 500 can be landed through a 20-in. riser using a
running tool in much the same manner as depicted in the example of
FIG. 8, with the exception that the running tool couples to the
outer threaded connection at the top .Iadd.or upper .Iaddend.end
.Iadd.503a .Iaddend.of the casing head 500. Moreover, the casing
head 500 and other components of FIGS. 10A-10B can be used with
completion spools, adapters, and other conventional components
similar to the arrangements in FIGS. 9A-9B (e.g., elements 70, 72,
74, 76, 77, 80, and 82).
The double-bowl type casing head as shown in FIGS. 10A-10B can be
used in various operations when several casing strings are to be
run downhole. FIGS. 11A-11D illustrate another wellhead completion
assembly 600 in various stages of assembly that can support several
casing strings. In addition, to being able to support multiple
strings, this assembly 600 has modular head components 610 and 620
that offer a number of advantages, including allowing the assembly
600 to be assembled in different arrangements and facilitating
contingency operations when a stuck pipe occurs before a hanger can
be properly landed in the head.
As shown in FIG. 11A, the modular assembly 600 includes first and
second head components 610 and 620. The first head component 610
can be similar to the casing head of previous embodiments, such as
casing head 100 in FIG. 2, and can be used alone in a single bowl
type of arrangement. Alternatively, the second head component 620
can connect to the first head component to make a double-bowl type
of casing head.
In assembling the double bowl arrangement, for example, the first
head component 610 connected to outer casing 12 lands on the
landing assembly 20, and the second head component 620 supported by
running tool 54 threads to the first component 610 at a threaded
connection 630. This threaded connection 630 can use the same type
of threading and rating as previous embodiments. For example, this
connection 630 can be similar to the connection 106 in FIG. 2
having ACME-2G left-handed thread form and can be 11-in. rated at a
working pressure of 10,000-PSI. Holes 632 and setscrews (not shown)
may also be used to couple the second component 620 to the first
component 610.
As shown in FIG. 11B, another running tool 54 runs a hanger 650 and
attached inner casing 14 through the head components 610/620 and
lands the hanger 650 on the shoulder 612 inside the first component
610. Subsequently, as shown in FIG. 11C, another running tool 56
lands a pack-off plate 660 above the hanger 650. The modular
assembly 600's resulting double-bowl type of arrangement is shown
in FIG. 11D. At this point in the assembly .Iadd.as shown in FIG.
11E.Iaddend., additional pack-off components .Iadd.522.Iaddend.,
another inner casing .Iadd.15.Iaddend., and an additional hanger
.Iadd.540 .Iaddend.can be landed in the second head component 620
.Iadd.and a head ring 550 can be used, .Iaddend.as with the
assembly in FIGS. 10A-10B. In this way, the modular assembly 600
can support multiple casing strings .Iadd.(e.g., 14, 15).Iaddend..
For example, an 11-inch embodiment of the assembly 600 could
support two casing strings, while a 13-inch embodiment of the
assembly 600 could support three casing strings.
As shown in FIGS. 11A-11D, the first and second head components
610/620 of the modular assembly 600 can be used to create a
double-bowl type of casing head. Because the disclosed assembly 600
is modular, the first head component 610 can be used by itself. As
shown in FIGS. 12A-12B, for example, the first head component 610
can be landed on the landing assembly 20 with a running tool 54,
and a quick connect drilling adapter 530 or some other desired
component can be attached to the first component 610 to complete
the assembly. Alternatively, the first head component 610 can be
used in other arrangements disclosed herein, such as in FIGS. 2,
3A, 4, and 9A-9B. In another alternative shown in FIG. 13, two of
the second head components 620a-b can be stacked on top of one
another above the first head component 610 to create a three
component modular assembly, which can be used to support multiple
casing strings.
Not only does the modular assembly 600 provide for versatile
arrangements, but it facilitates contingency operations when a
stuck pipe occurs. When running the casing 14 and hanger 650
through the head components 610/620 and the outer casing 12, for
example, the inner casing 14 may become stuck in what is commonly
referred to as a stuck pipe situation--an example of which is shown
in FIG. 14A. Because the inner casing 14 cannot be inserted enough
to allow the attached hanger 650 to be landed on the shoulder 612,
operators must perform a contingency operation that involves using
slips to secure the inner casing 14 in tension within the casing
head and cutting the excess portion from the inner casing 14 that
has been prevented from passing through the casing head.
In a conventional double-bowl casing head, cutting the excess
casing can be difficult because the point at which the cut must be
made lies deep within the double-bowl casing head. In other words,
an operator has to carefully cut the casing within the confined
space of the double-bowl head with a welding tool and then to
prepare the end of the cut casing properly for further
operations.
The modular assembly 600, however, facilitates stuck pipe
contingency operations. When a stuck pipe occurs as in FIG. 14A,
operators position a slip assembly 670 and pack-off 672 in the
first component 610 as shown in FIG. 14B and then remove the second
component 620 from the first component 610 at the threaded
connection 630. Removing the second component 620 leaves the excess
casing 14 exposed above the first component 610. Operators can then
more readily cut the excess casing 14 at the appropriate point,
level the cut end 15, and create the needed chamfer at the edge.
After these steps have been completed, operators can reconnect the
second component 620 to the first component 610. Alternatively,
operators can attach a rotating flange 674 to the connection end
631 of the first component 610 as shown in FIG. 14C or couple
components of some other desired arrangement to the first component
610.
In addition to facilitating preparation of the inner casing 14
during stuck pipe contingency operations, the modular assembly 600
also helps operators perform modifications to a control line when a
stuck pipe occurs. For example, FIG. 15A shows the modular assembly
600 having a control line 700 that runs down the annulus to a valve
or the like (not shown). The control line 700 connects by a ferrule
coupling 702 to a hanger 650, and a side coupling 704 in the first
head component 610 communicates with a port in the hanger 650 to
communicate with the control line 700.
If a stuck pipe occurs while running the inner casing 14, the
hanger 650, and the control line 700 downhole, operators have to
modify the arrangement of the control line 700 to connect it to the
side coupling 704. In a conventional double-bowl type of head,
operators would have to modify the control line's connection by
making modifications deep within the double-bowl head and confined
in the annulus between the inner casing and the head.
The disclosed modular assembly 600, however, alleviates some of
this difficulty. For example, as shown in FIG. 15B, the second
component 620 can be removed from the first head component 610
giving operators easier access to the control line 700 and the
inside of the coupling 704. Before putting the slip assembly 670
and pack-off 672 in the head, for example, operators can wind
excess amounts of control line 700 in wraps 705 around the casing
14 and attach the line 700 to the coupling 704 inside the first
component 610 while having easier access inside the annulus. After
setting up the control line 700, putting the slip assembly 670 and
pack-off 672 in the first head component 610, and cutting the
excess of the casing 14, operators can reconnect the second
component 620 to the first component 610. Alternatively, operators
can attach a rotating flange 674 to the end .Iadd.630 .Iaddend.of
the first component 610 as shown in FIG. 15C, or couple components
of some other desired arrangement to the first component 610.
The foregoing description of preferred and other embodiments is not
intended to limit or restrict the scope or applicability of the
inventive concepts conceived of by the Applicants. For example, it
will be appreciated with the benefit of the present disclosure that
components of one embodiment of the wellhead completion assembly
can be combined with components of another embodiment to produce a
variety of versatile arrangements for well completions. In exchange
for disclosing the inventive concepts contained herein, the
Applicants desire all patent rights afforded by the appended
claims. Therefore, it is intended that the appended claims include
all modifications and alterations to the full extent that they come
within the scope of the following claims or the equivalents
thereof.
* * * * *
References