U.S. patent application number 10/252185 was filed with the patent office on 2003-01-30 for port collar assembly for use in a wellbore.
This patent application is currently assigned to Weatherford/Lamb.. Invention is credited to Freiheit, Roland R., Gullory, Brett, Wilkin, James F..
Application Number | 20030019630 10/252185 |
Document ID | / |
Family ID | 24364399 |
Filed Date | 2003-01-30 |
United States Patent
Application |
20030019630 |
Kind Code |
A1 |
Freiheit, Roland R. ; et
al. |
January 30, 2003 |
Port Collar assembly for use in a wellbore
Abstract
The present invention generally provides a port collar assembly
comprising a housing and a sleeve disposed therein. The sleeve is
moveable between a first or opened and a second or closed position
relative to the housing. In the closed position, the port collar
prevents communication of the fluid between the exterior and
interior of the port collar. In the open position, the port collar
permits communication of the fluid between the exterior and
interior of the port collar. The assembly includes a locking
mechanism for the opened and closed positions comprising ratchet
teeth formed on the exterior surface of the sleeve and mating
ratchet teeth formed on the interior surface of the housing. The
mating ratchet teeth are designed to secure the sleeve in a first
position within the housing. A second set of mating ratchet teeth
secures the sleeve in a second position.
Inventors: |
Freiheit, Roland R.;
(US) ; Gullory, Brett; (Woodlands, TX) ;
Wilkin, James F.; (Sherwood Park, CA) |
Correspondence
Address: |
William B. Patterson
MOSER, PATTERSON & SHERIDAN, LLP
Suite 1500
3040 Post Oak Blvd.
Houston
TX
77056
US
|
Assignee: |
Weatherford/Lamb.
|
Family ID: |
24364399 |
Appl. No.: |
10/252185 |
Filed: |
September 23, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10252185 |
Sep 23, 2002 |
|
|
|
09590949 |
Jun 9, 2000 |
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Current U.S.
Class: |
166/332.4 |
Current CPC
Class: |
E21B 34/14 20130101 |
Class at
Publication: |
166/332.4 |
International
Class: |
E21B 034/14 |
Claims
1. A port collar comprising: a housing with at least one aperture
through a wall thereof; a sleeve disposed within the housing, the
sleeve repeatably shiftable between an open and closed position in
relation to the housing, the sleeve having at least one aperture
through a wall thereof to align with the at least one aperture in
the housing when the sleeve is in the open position thereby
permitting fluid communication between an outside and inside of the
port collar; and a locking system to retain the sleeve in the open
or closed position.
2. The port collar assembly of claim 1, wherein the locking system
includes a first locking surface formed upon a perimeter of the
sleeve and a first mating locking surface disposed upon an inner
surface of the housing to prevent axial movement of the sleeve in a
first direction with respect to the housing.
3. The assembly of claim 2, wherein the locking system further
includes a second locking surface formed upon the perimeter of the
sleeve and a second mating locking surface disposed upon the inner
surface of the housing to prevent axial movement of the sleeve in a
second direction with respect to the housing.
4. The assembly of claim 3, wherein the first and second mating
locking surfaces are formed upon the inner surface of an inwardly
biased C-ring disposed in a groove formed in the inner surface of
the housing, the C-ring expandable in an outward direction into the
groove.
5. The assembly of claim 3, wherein each of the first and second
locking surfaces include ratchet teeth formed around the outer
perimeter of the sleeve and each of the first and second mating
locking surfaces include an opposing row of ratchet teeth, whereby
the rows of ratchet teeth and the opposing rows of ratchet teeth
move across each other in a first direction but interfere with each
other in an opposite direction, thereby retaining the sleeve in the
opened or closed position within the housing.
6. The assembly of claim 5, further including at least one button
disposed in an aperture formed in the locking surface of the
sleeve, the button movable in an outwardly radial direction to
cause the expandable C-ring to expand into the groove and move the
mating locking surface of the housing out of engagement with the
locking surface of the sleeve, thereby allowing axial movement of
the sleeve in the first direction.
7. The assembly of claim 6, further including at least one button
disposed in an aperture formed in the locking surface of the
sleeve, the button movable in an outwardly radial direction to
cause the expandable C-ring to expand into the groove and move the
mating locking surface of the housing out of engagement with the
locking surface of the sleeve, thereby allowing axial movement of
the sleeve in the second direction.
8. The assembly of claim 7, wherein the sleeve is movable between
the open and closed positions by a shifting tool inserted
therein.
9. The assembly of claim 8, wherein the shifting tool includes a
plurality of longitudinally formed slots, creating flexible fingers
therebetween.
10. The apparatus of claim 9, wherein the flexible fingers of the
shifting tool include a formation formed on the outer surface
thereof, the formation constructed and arranged to urge at least
one button in an outwardly radial direction, thereby unlocking the
locking system and permitting movement of the sleeve in the first
direction.
11. The apparatus of claim 10, wherein the flexible fingers of the
shifting tool include a formation formed on the outer surface
thereof, the formation constructed and arranged to urge at least
one button in an outwardly radial direction, thereby unlocking the
locking system and permitting movement of the sleeve in the second
direction.
12. The apparatus of claim 11, wherein the formations formed on the
flexible fingers serve to fix the flexible fingers within the
sleeve.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to port collars for use in a
tubular string. Specifically, the invention relates to a
two-position port collar which can be repeatedly opened and closed
and securely retained in each position.
[0003] 2. Background of the Related Art
[0004] Port collars typically have a tubular housing which can be
made up into a tubular string to form a part thereof. The port
collar has a sliding sleeve disposed therein which may be used to
selectively communicate fluid flow between an annular area of the
well and an interior of the tubing string. In one example, a port
collar is installed in a tubular string in a closed position and
the tubular string is then inserted into a wellbore, locating the
port collar at a predetermined depth in the well. Packing elements
are installed above and below the port collar to isolate a specific
zone of the annulus. Thereafter, the sliding sleeve of the port
collar is remotely opened and the interior of the tubular is placed
into communication with production fluid in the annulus. The port
collar may also be used to permit fluid flow from the interior of
the tubing string into the annulus of a well. For example, in
cementing deep wells, a two-part cementing job is often used
wherein the lower portion of a casing or liner string is cemented
and then, using a port collar, the upper annulus is cemented to
avoid hydrostatic pressures present in the lower portion of the
annulus.
[0005] While many port collar designs have been made and used,
certain problems exist with current designs. For example, most port
collars rely on shear screws or some other type of mechanically
shearable connection to unlock the sleeve from an initial position
and permit movement of the sleeve to a second position within the
collar. In a typical example, the shearable connection holds the
sleeve in a closed position and then, when the collar is in the
wellbore and ready to be opened, the shearable members are caused
to fail with mechanical or hydraulic force. Once the shearable
connection has failed, the sleeve is left prone to accidental
shifting in the housing, unless it is permanently locked into
either an open or closed position.
[0006] There is a need therefore, for a port collar that does not
rely on a shearable connection to lock the sleeve into position
within the housing. There is a further need for a port collar that
can be repeatedly shifted and locked into the opened and closed
positions. There is yet a further need for an easily shiftable port
collar that can be used with other port collars in a single tubular
string to create a larger assembly for selectively exposing
different areas of an annulus to communication with the interior of
the tubing string.
SUMMARY OF THE INVENTION
[0007] The present invention generally provides a port collar
assembly comprising a housing and a sleeve disposed therein. The
sleeve is moveable between a first or opened and a second or closed
position relative to the housing. In the closed position, the port
collar prevents communication of the fluid between the exterior and
interior of the port collar. The assembly includes a locking system
for each position comprising ratchet teeth formed on the exterior
surface of the sleeve and mating ratchet teeth formed on the
interior surface of the housing. One set of mating ratchet teeth
are designed to secure the sleeve in an opened position within the
housing and a second set of mating ratchet teeth secures the sleeve
in a closed position. In one aspect of the invention, the ratchet
teeth on the interior surface of the housing are formed on the
inner surface of an inwardly biased C-ring disposed in a groove
formed in the interior surface of the housing. A plurality of
buttons are disposed within apertures formed in the exterior
surface of the sleeve and the buttons can be urged in an outward
radial direction by a shifting tool disposed within the sleeve. The
buttons urge the C-rings into the grooves of the housing and out of
engagement with the mating ratchet teeth formed on the surface of
the sleeve. In this manner, the sleeve and housing are unlocked
from each other and the tool can be shifted to the other
position.
[0008] In another aspect of the invention, cavities and shifting
shoulders are formed on the interior of the sleeve opposite each
locking system. Corresponding unlocking and detenting formations
are formed on a shifting tool including a formation designed to
urge the buttons of the sleeve in a radial outward direction. A
shifting surface on the shifting tool, corresponding to a shoulder
formed on the interior of the sleeve, allows a force to be applied
to move the sleeve to a second location in the housing after being
unlocked.
[0009] In another aspect of the invention, several port collars are
installed in a tubular string in a wellbore. Thereafter, in order
to open and close the port collars, a number of shifting tools are
run into the well on a run-in string in a pre-determined,
spaced-apart orientation. The shifting tool at the lowest point on
the string opens each port collar as it passes therethrough. In
order to close the port collars, the string of shifting tools is
pulled upwards and the shifting tool designed to close the port
collars closes each collar as it passes therethrough. By accurately
spacing the shifting tools along the run-in string, the direction
of the string can be reversed in order to open a certain port
collar while leaving the others in a closed position.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] So that the manner in which the above recited features,
advantages and objects of the present invention are attained and
can be understood in detail, a more particular description of the
invention, briefly summarized above, may be had by reference to the
embodiments thereof which are illustrated in the appended
drawings.
[0011] It is to be noted, however, that the appended drawings
illustrate only typical embodiments of this invention and are
therefore not to be considered limiting of its scope, for the
invention may admit to other equally effective embodiments.
[0012] FIG. 1 is a partial section view showing the port collar of
the present invention in an open position.
[0013] FIG. 1A is an enlarged view of a locking portion of the port
collar of FIG. 1.
[0014] FIG. 2 is a partial section view of the port collar in a
closed position.
[0015] FIG. 3 is a perspective, side view of a shifting tool used
to open the port collar including an opening portion and a closing
portion.
[0016] FIG. 4 is a section view showing the port collar in the open
position with a shifting tool installed therein.
[0017] FIG. 4A is an enlarged view showing the opening portion of
the shifting tool engaged in the sleeve of the port collar.
[0018] FIG. 5 is a section view showing a collet-like function of
the shifting tool.
[0019] FIG. 5A is an enlarged view thereof.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0020] FIG. 1 is a side view, partially in section of the port
collar 200 of the present invention. The port collar 200 includes a
housing 205, which is typically connected at each end to a tubular
string (not shown). The housing 205 includes a plurality of housing
apertures 210 formed in a wall thereof and constructed to align
with sleeve apertures 212 formed in a wall of a sleeve 206 when the
port collar 200 is in an open position as in FIG. 1. The sleeve 206
is disposed within the housing 205 and is installed therein in a
certain rotational orientation which is predetermined and is
secured with lock screws or set screws (not shown) between the
housing 205 and the sleeve 206. Axial movement of the sleeve 206
within the housing 205 is limited by stops 215, 217 formed at each
end of the interior of the housing 205. The stops prevent axial
movement of the sleeve 206 within the housing beyond that movement
necessary to locate the sleeve 206 in the open or closed
position.
[0021] The port collar 200 includes a first locking system,
generally labeled 300 to retain the sleeve 206 in a closed position
and a second locking system 301 to retain the sleeve in an open
position. In FIG. 1, locking system 301 is engaged and the port
collar 200 is locked in the open position with fluid communication
possible between the inside and outside of the port collar 200
through aligned apertures 210, 212. The sleeve 206 is prevented
from axial movement in a first direction by stop 217 and in the
direction of the closed position by engaged locking system 301.
[0022] Each locking system 300, 301 includes locking surfaces
formed on the perimeter of the sleeve 206 and locking surfaces
formed on the inner surface of the housing 205. The surfaces
prevent the sleeve 206 from moving within the housing 205 in one
direction. FIG. 1A is an enlarged view showing a portion of engaged
locking system 301. Specifically, the locking surface formed on the
sleeve 206 includes ratchet teeth 325 extending around the sleeve
perimeter. In the preferred embodiment, the mating locking surface
of the housing 205 includes at least one groove 365 formed in the
inner surface of the housing with an inwardly biased C-ring 370
disposed therein. On the inside surface of the C-ring 370, facing
the sleeve 206, ratchet teeth 375 are formed and are designed to
interact with ratchet teeth 325 formed on the exterior of the
sleeve 206 such that the sleeve 206 is prevented from axial
movement in the housing 205 in a first direction when the mating
teeth 325, 375 of the sleeve and the C-ring are engaged. As
depicted in FIG. 1A, the engaged ratchet teeth 325, 375 will move
across each other with little resistance in a first direction but
will interfere with each other preventing movement in a second
direction. Specifically, the design allows the ratchet teeth 325,
375 to move across each other as the port collar 200 is shifted to
the open position shown in FIG. 1. Thereafter, the interaction of
the teeth 325, 375 prevent the sleeve 206 from moving back towards
the closed position. In the open position therefore, the sleeve 206
is prevented from axial movement in one direction by stop 217
acting between the sleeve 206 and the housing 205 and in the
opposite direction by the locking system 301.
[0023] Interspersed with the ratchet teeth 325 on the outer
perimeter of the sleeve 206 are at least one button 335, one of
which is visible in FIG. 1A. The buttons 335 are housed in
countersunk apertures 336 formed in the sleeve 206 and a head
portion 337 of each button 335 is retained on a reduced diameter
shoulder 338 formed in each aperture. The buttons can be urged
outwardly radially by a shifting tool described hereafter. The
placement of apertures 336 with the buttons 335 therein correspond
to the location of the ratchet teeth 325 formed on the outer
surface of the sleeve 206 such that the buttons 335, when urged
outwards, extend out above the ratchet teeth 325. By urging the
buttons outward, the head portion 337 of the buttons move the
inwardly biased C-ring 370 back into the groove 365 and out of
engagement with the ratchet teeth 325 of the sleeve. In this
manner, the locking system 301 is unlocked and the sleeve 206 can
be moved axially within the housing 205. The number of buttons
utilized can be increased for redundancy. Additionally, each
locking system can utilize multiple locking surfaces. For example,
if a particular tool is run through a port collar and one set of
buttons is inadvertently urged outwards thereby disengaging a first
C-ring, a second C-ring with its locking surface will remain
engaged with corresponding ratchet teeth of the sleeve, thereby
preventing premature shifting of the port collar.
[0024] FIG. 2 is a partial section view showing the port collar 200
in a closed position with the sleeve apertures 212 out of alignment
with the housing apertures 210. In the closed position, there is no
fluid communication between the interior and exterior of the port
collar 200. As with locking system 301, locking system 300 includes
ratchet teeth formed on the exterior of the sleeve 206 and ratchet
teeth formed on the inside surface of a C-ring housed in a groove
formed on the inside surface of housing 205. In the closed
position, the sleeve 206 is prevented from movement in a first
axial direction by stop 215 and in the direction of the open
position by the engaged locking system 300.
[0025] Unlocking and shifting of the port collar 200 between the
open and closed positions are performed through the use of a
shifting tool. FIG. 3 is a perspective view of shifting tool 400
which is comprised of an opening portion 410 and closing portion
450, each portion having an opposing orientation along the length
of the shifting tool. Portions 410, 450, when run into the
wellbore, are independently seated in the interior of the port
collar sleeve 206. FIG. 3 illustrates the opening portion 410
including a tool oriented to open the port collar 200 and closing
portion 450 oriented to close the port collar 200. The spacing
between the opening 410 and closing 450 portions is adjustable
depending upon operational conditions and requirements. Each
portion 410, 450 of the shifting tool 400 includes collet-like
features with a plurality of slots 436 formed longitudinally within
the tool. The slots create fingers 435 therebetween which move in a
spring-like manner when force is applied to the surface thereof. In
the preferred embodiment, at least four equally spaced fingers 435
are formed around the shifting tool 400.
[0026] Considering the opening portion 410 of the tool in greater
detail, each finger 435 includes two unlocking formations 412, 430
designed to interact with corresponding surfaces on the interior of
the sleeve 206. Unlocking formation 430 also serves to move the
sleeve 206 within the housing 205 via engagement between surfaces
of the formation 430 and the sleeve 206. Unlocking formations 412,
430 include upper surfaces 413, 431 substantially parallel to the
surface of finger 435 and three angled surfaces 414, 415, 433.
Unlocking formation 430 also includes one shifting surface 432
substantially perpendicular to the surface of finger 435. The
shifting surface 432 provides a means to urge the sleeve 206 from
the closed to the open position as described hereafter. A detenting
formation 420 has one upper surface 421 substantially parallel to
finger 435 and two angled surfaces 422, 423.
[0027] Closing portion 450 similarly includes two unlocking
formations 470, 480 and are detenting formation 460. As with the
opening portion, formations 480, 470 include surfaces 481, 471
substantially parallel to the surface of finger 435 and three
angled surfaces 483, 472, 473. Additionally, shifting formation 480
includes shifting surface 482 substantially perpendicular to finger
435. A detenting formation 460 includes an upper surface 461 and
also a two surfaces 462, 463 angled to the surface of finger
435.
[0028] Formed in the interior of the sleeve 206, opposite each
locking system 300, 301 are cavities constructed and arranged to
interact with the formations and surfaces of the shifting tool 400.
FIG. 4 is a partial section view of the port collar 200 showing the
closing portion 450 of the shifting tool 400 engaged with the
corresponding cavities in the sleeve opposite locking system 301.
With the closing portion 450 of the shifting tool 400 inserted, the
sleeve 206 may be urged in the direction of stop 215, mis-aligning
the apertures 210, 212 of the sleeve and housing and closing the
port collar 200. As illustrated in FIG. 4A, an enlarged view of
locking system 301, formations 460, 470, 480 of the closing portion
450 of the shifting tool 400 have engaged corresponding cavities of
the sleeve 206. The interior of the sleeve 206 opposite locking
system 301 includes two unlocking cavities 430, 436 and one
shifting shoulder 440 constructed and arranged to interact with
unlocking formations 470, 480 and detenting formation 460 formed on
the closing portion 450 of the shifting tool 400. In FIG. 4A,
shifting surface 482 of the shifting tool is in contact with
shoulder 440 of the sleeve 206. Surfaces 481, 471 of formations
470, 480 have contacted the lower surface 338 of buttons 335
disposed in the sleeve 206 and the buttons have been urged outwards
in a radial direction. The head portion 337 of each button 335 has
contacted and urged the C-rings 370 into the grooves 365 formed on
the interior surface of the housing 205. In this manner, the
ratchet teeth 375 have been moved out of engagement with the mating
ratchet teeth 325 (not visible) on the exterior of the sleeve
206.
[0029] With the ratchet teeth 325, 375 out of engagement, force
applied against shoulder 440 by shifting surface 482 will cause the
sleeve 206 to move axially within the housing 205. As the sleeve
206 moves into the closed position, axial movement of the sleeve
206 is limited by stop 215 and locking system 301 will prevent
axial movement towards the open position, thereby locking the port
collar 200 in the closed position. As visible in FIG. 1, there are
two cavities 437, 434 and a shifting shoulder 436 opposite locking
system 300 to interact with formations 412, 430 and shifting
surface 432 of the opening portion 410 of the shifting tool 400.
Locking system 300 is disengaged in a similar manner as locking
system 301 and those skilled in the art will appreciate that the
foregoing description is equally applicable to locking system
300.
[0030] FIG. 5 is a partial section view of the port collar 200
having been shifted to the open position by the opening portion 410
of the shifting tool 400. FIG. 5 illustrates the collet-like
movement of the fingers 435 allowing the opening portion 410 of the
shifting tool 400 to be urged out of engagement with the sleeve
206. FIG. 5A is an enlarged view showing the interaction of the
various surfaces of the shifting tool 410, sleeve 206 and housing
205. After the port collar is shifted to the open position and
additional axial movement of the sleeve 206 is prevented by stop
217, continued force applied to the shifting tool will cause a
surface 423 of the detenting formation 420 to contact and move
downward across an undercut surface 218 of the sleeve 206 formed
below stop 217. The downward component of force exerted upon
surface 423 urges the flexible finger 435 downward until shifting
surface 432 is no longer in contact with corresponding shoulder 502
of sleeve 206. In this manner, the shifting tool 400 can be moved
out of engagement with the port collar.
[0031] Typically, a port collar 200 is placed in a well in the
closed position whereby the annular area around the port collar 200
is isolated from the interior of the port collar. In order to open
the port collar 200, a shifting tool 400 is run into the well on a
run-in string of tubular. The opening 410 and closing 450 portions
of the shifting tool 400 allow the port collar 200 to be opened and
then closed again at the completion of some downhole operation. As
the shifting tool enters the closed port collar, the opening
portion 410 passes through the formations opposite the locking
system 301 and subsequently, the opening portion 410 interacts with
formations opposite the locking system 300 and the shifting tool
becomes fixed within the sleeve 206. In this position, the shifting
tool urges the buttons 335 of the locking system 300 outwards
thereby moving the Crings 370 out of engagement with the ratchet
teeth 325 of the sleeve. Continued force applied to the shifting
tool 400 will then urge the sleeve 206 down and into the open
position. Thereafter, continued force upon the shifting tool 400
causes the collet-like fingers of the opening portion 410 of the
shifting tool to collapse and come out of engagement with cavities
of the sleeve 206, as illustrated in FIG. 5A.
[0032] The present invention can also be used in a wellbore wherein
numerous port collars 200 are arranged in series at various depths
in the well and are then alternately opened or closed by multiple
shifting tools run into the well along a run-in string. For
example, port collars 200 can be located adjacent formations and
then selectively opened to access production fluid. Subsequently,
the port collars 200 can be re-closed isolating the interior
thereof from the annular well fluid. In other examples, the port
collars 200 are opened to permit cement to be injected into the
annular area therearound and then re-closed after the cementing
process is complete.
[0033] As a run-in string with shifting tools installed therein is
lowered into a wellbore, the opening tool portion 410 of the
shifting tool opens the port collars as it passes therethrough.
Closing portion 450 of the shifting tool, because it is designed to
operate only while moving in an upward direction through the port
collars 200, passes downward through the port collars 200 with no
effect. After the shifting tool 400 has passed through and opened
all of the port collars 200, the run-in string housing the shifting
tools can be pulled upwards towards the surface of the well such
that the closing portion of a shifting tool 450 will re-close the
lower most port collars. Finally, if necessary, the opening portion
410 of the shifting tool 400 can then be lowered back through an
intermediate port collar(s), leaving the port collar(s) in the open
position. In this manner, port collars are selectively opened and
closed in a string of multiple port collars.
[0034] While foregoing is directed to the preferred embodiment of
the present invention, other and further embodiments of the
invention may be devised without departing from the basic scope
thereof, and the scope thereof is determined by the claims that
follow.
* * * * *