U.S. patent number 3,568,715 [Application Number 04/724,304] was granted by the patent office on 1971-03-09 for well tools.
This patent grant is currently assigned to Otis Engineering Corporation. Invention is credited to Donald F. Taylor, Jr..
United States Patent |
3,568,715 |
Taylor, Jr. |
March 9, 1971 |
WELL TOOLS
Abstract
This invention relates to well tools and more particularly to a
flow conductor assembly for use in a well installation employed
during the drilling of a well and to well tools usable in such flow
conductor assembly.
Inventors: |
Taylor, Jr.; Donald F. (Dallas,
TX) |
Assignee: |
Otis Engineering Corporation
(Dallas, TX)
|
Family
ID: |
27042917 |
Appl.
No.: |
04/724,304 |
Filed: |
February 8, 1968 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
|
469978 |
Feb 8, 1968 |
3411576 |
|
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Current U.S.
Class: |
137/613;
137/614.2; 166/321 |
Current CPC
Class: |
E21B
43/01 (20130101); E21B 34/045 (20130101); Y10T
137/87917 (20150401); Y10T 137/88054 (20150401); E21B
2200/04 (20200501) |
Current International
Class: |
E21B
34/00 (20060101); E21B 34/04 (20060101); E21B
43/01 (20060101); E21B 43/00 (20060101); E21b
023/00 () |
Field of
Search: |
;137/613,614.2,495,496
;251/62 ;166/224 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: O'Dea; William F.
Assistant Examiner: Wright; William H.
Parent Case Text
This application is a division of Ser. No. 469,978 filed Feb. 8,
1968 now U.S. Pat. No. 3,411,576.
Claims
I claim:
1. A valve including: a tubular housing having a longitudinal flow
passage therethrough; a pair of longitudinally spaced valve means
in said housing coacting with each other for individually closing
said longitudinal passage to fluid flow therethrough; means
resiliently biasing each of said pair of valve means to a position
individually closing said housing flow passage; said housing having
spaced means at its upper end for connecting said housing to the
lower ends of a pair of upper flow conductors and means at its
lower end for connecting said housing to the upper end of a third
flow conductor therebelow whereby fluid may flow through said
housing through said flow passage from the third flow conductor to
one of the pair of upper conductors; said housing having passage
means for conducting control fluid to each of said pair of valve
means from the other of said pair of upper fluid conductors for
moving said pair of valve means against the force of said biasing
means to open position to permit flow through said housing flow
passage from said third flow conductor to said one of said pair of
upper flow conductors.
2. A valve including: a tubular housing having a longitudinal
passage therethrough; a pair of longitudinally spaced valve means
in said housing for individually closing said longitudinal passage
to fluid flow therethrough, said housing having spaced connecting
means at its upper end for connecting said housing to the lower
ends of a pair of upper flow conductors and connecting means at its
lower end for connecting said housing to the upper end of a third
flow conductor therebelow whereby fluid may flow through said
housing passage from said third flow conductor to one of said
connecting means and to one of said upper pair of flow conductors
connected therewith; said valve means including biasing means
biasing each of the valve means to closed position and fluid
pressure responsive means for moving each of the valve means to
open position against the resistance of said biasing means, said
housing having control fluid passage means opening upwardly at its
upper end to the other of said connecting means for conducting
control fluid pressure from the other of said pair of upper flow
conductors to said pressure responsive means of said pair of valve
means for opening said valve means.
3. A valve including: a tubular housing having a longitudinal flow
passage therethrough; a pair of longitudinally spaced valve means
in said housing coacting with each other for individually closing
said longitudinal passage to fluid flow therethrough, said housing
having spaced means at its upper end for connecting said housing to
the lower ends of a pair of upper flow conductors and means at its
lower end for connecting said housing to the upper end of a third
flow conductor therebelow whereby fluid may flow through said
housing from the third flow conductor to one of the pair of upper
conductors; said housing having passage means for conducting
control fluid to said valve means from the other of said pair of
upper fluid conductors for moving said pair of valve means to open
position to permit flow from said third flow conductor to said one
of said pair of upper flow conductors, wherein said valve means
includes: a tubular piston, and a tubular piston member
longitudinally movable in said housing, said piston and said piston
member having longitudinal passage means therethrough; coengageable
means on said piston and said piston member limiting movement of
said piston member relative to said piston; a ball including a flow
passage mounted in said longitudinal passage of said housing for
movement between positions opening and closing said longitudinal
passage of said housing; and means operatively associated with said
piston member and ball for moving said ball between said open and
closed positions upon predetermined longitudinal movement of said
piston member in said housing; said piston member being movable
relative to said housing to cause said ball to move to said open
position when said piston member is in its upper position and the
control fluid pressure in said control fluid passage means of said
housing above said piston means is increased to a predetermined
value to move said ball to open position.
4. The valve of claim 1, wherein each of said valve means includes:
a tubular piston member; a ball having a flow passage therethrough
mounted in said longitudinal passage of said housing, said ball and
said piston member having coengageable means for moving said ball
between open and closed positions in said longitudinal passage of
said housing; means operatively associated with said piston member
and said ball and with said biasing means for causing said ball be
biased to move with said piston member to said closed position
wherein said ball prevents fluid flow through said housing; said
piston being exposed to control fluid pressure from said housing
control fluid passage means for moving said valve against the force
of said housing means to an open position wherein said ball permits
flow through said flow passage of said housing.
5. A valve including: a housing having a longitudinal flow passage
therethrough; spaced means at the upper end of said housing for
connecting a pair of flow conductors to said housing; means at the
lower end of said housing for connecting a third flow conductor to
said housing; a pair of longitudinally spaced tubular piston means
having a longitudinal flow passage therethrough communicating with
the flow passage of the housing and longitudinally movable in said
passage and each having external annular flange means thereon, each
of said pair of piston means and said housing defining separate
annular chamber means therebetween above said flange means of each
of said piston means; seal means sealing between each of said
piston means and said housing above and below said chamber means;
means on said housing providing a fluid passage opening to each of
said annular chamber means and to one of said spaced connecting
means at the upper end of said housing for conducting fluid
pressure from the flow conductor connected with said one connecting
means to each of said chamber means; said flange means of each of
said tubular piston means being exposed to fluid pressure in said
annular chamber means in which each of said flange means is
disposed for downward movement of said piston means by said fluid
pressure; resilient means biasing each of said piston means
upwardly in said housing opposite the force of the fluid pressure
in said annular chamber means; a pair of ball closure members
rotatably mounted in said housing and each having a flow passage
therethrough disposed to communicate with the longitudinal passage
of one of said piston means when in one position and movable to
another position closing said longitudinal passage of said one of
said piston means; means operatively connecting each of said ball
closure members separately with one of said piston means; said ball
closure members, said piston means and said housing having
coengageable means for moving said ball closure members between
closed positions and open positions upon longitudinal movement of
the piston means in the housing, whereby said ball closure members
are each moved to and held in open positions by fluid pressure in
said chamber means acting on said flange means of said piston means
and are each moved to closed positions by said resilient biasing
means when said fluid pressure acting on said flange means of said
piston means is sufficiently reduced or relieved.
6. A valve including: a tubular housing having a flow passage
extending longitudinally therethrough; a pair of longitudinally
spaced separate valve means in said housing each separately biased
to a position closing said flow passage against fluid flow
therethrough; separate fluid pressure responsive means operatively
connected with each of said valve means for moving said valve means
to a position opening said flow passage to flow therethrough; upper
connector means on the upper end of said housing for connecting
said housing to the lower ends of a pair of upper flow conductors,
and connector means at the lower end of said housing for connecting
said housing to the upper end of a third flow conductor, one of
said upper connector means and said lower connector means
communicating with the flow passage of the housing whereby fluid
may flow through said housing from the third flow conductor to one
of the pair of upper flow conductors; said housing having passage
means therein communicating with the other upper connector means
and with said valve means for conducting control fluid from the
other of said pair of upper flow conductors to said fluid pressure
responsive means of each of said valve means for moving said pair
of valve means to open position to permit flow from said third flow
conductor to said one of said pair of upper flow conductor.
7. A valve of the character set forth in claim 6 wherein: each of
said fluid pressure responsive means operatively connected with
said valve means comprises a pair of separate piston means provided
in said tubular housing operably each connected with one of said
valve means and exposed to control fluid pressure from said passage
means of said housing whereby said pair of valve means is operated
by the pressure of the control fluid supplied to said piston means
through said passage means to move the valve means to open
position.
8. A valve of the character set forth in claim 6 wherein: a pair of
separate resilient means is provided in said housing each coacting
with one of said valve means for biasing said valve means to closed
position upon relief of control fluid pressure acting on said
piston means to close said valve means to prevent flow from the
third flow conductor to said one of said upper connector means.
9. A valve of the character set forth in claim 7 wherein: said
housing has guide means at its upper end having openings formed
therein for guiding said one of said upper flow conductors to said
one upper connector means at the upper end of said housing for
releasably connecting said one of said upper flow conductors to
said valve housing; said guide means also having guide means for
said other of said pair of upper flow conductors for guiding said
other of said pair of flow conductors to said other upper connector
means of said housing for releasable connection therewith.
10. A valve including: a tubular housing having a longitudinal flow
passage therethrough; a pair of longitudinally spaced rotary ball
valve means in said housing each having a flow passage
therethrough, said ball valve means being each rotatable in said
housing to a position individually closing said longitudinal flow
passage to fluid flow therethrough; a pair of connector means on
said housing at the upper end thereof for connecting said housing
to the lower ends of a pair of upper flow conductors; connector
means at the lower end of said housing for connecting said housing
to the upper end of a third flow conductor; said lower connector
means and one of said upper connector means communicating with said
housing flow passage whereby fluid may flow through said housing
and said spaced ball valve means from said third flow conductor to
one of said upper pair of flow conductors; resilient means in said
housing coacting with each of said pair of ball valve means for
biasing said ball valve means to closed position; fluid pressure
responsive means in said housing operatively connected with each of
said ball valve means and responsive to fluid pressure for moving
each of said ball valve means to open position against the
resistance of said resilient biasing means; said housing having
passage means therein communicating with the other of said upper
connector means at the upper end of said housing and with said
pressure responsive means for conducting control fluid under
pressure from the other of said pair of upper flow conductors to
said pressure responsive means for moving each of said ball valve
means to open position against the force of said resilient biasing
means to open the housing flow passage to flow therethrough.
11. A valve of the character set forth in claim 10 wherein said
pressure responsive means comprises a pair of piston means in said
valve housing each separately operatively connected with one of
said ball valve means and exposed to the pressure of said control
fluid from said passage means to be actuated by pressure of such
control fluid to move said ball valve means to open position.
12. A valve of the character set forth in claim 11 wherein said
resilient means comprises a pair of spaced springs each operatively
associated with one of said piston means for biasing said piston
means to a position in which the ball valve means with which it is
connected is moved to closed position.
13. A device of the character set forth in claim 10 wherein means
is provided in said valve for conducting fluid pressure of the
fluids flowing through the valve to each of said piston means to
act on said piston means in coaction with said resilient means to
move said ball valve means to closed position.
14. A device of the character set forth in claim 9 wherein each of
said pair of ball valve means comprises a separate ball valve
closure member and said pressure responsive means comprises a pair
of separate operator pistons, and each said ball valve closure
member is releasably connected with a separate one of said operator
pistons and said connection is releasable under a predetermined
force applied to said ball valve closure member, whereby fluid
pressure from said one of said upper flow conductors may be applied
to said ball valve closure members in sequence to move said ball
valve closure members to a position permitting flow therethrough to
the pipe below the valve.
15. A device of the character set forth in claim 13 wherein said
means for conducting fluid pressure to said operator piston also
when said valve closure members are in closed position serves to
conduct the pressure of the fluids downstream of said valve closure
members to said piston means to aid said resilient means in biasing
said closure members closed.
Description
An object of this invention is to provide a new and improved flow
conductor assembly, which is installable in the well installation
employed during the drilling of a well, through which various
operations may be performed, such as perforating, short time
production testing, and the like.
Still another object is to provide a flow conductor assembly which
is held in place in the well installation by a blowout preventer of
the well installation which was used in the drilling of the
well.
Still another object is to provide a flow conductor assembly having
a flow conductor through which fluids may flow between the surface
and the well which is provided with a valve located below the
blowout preventer and which may be controlled from the surface.
A further object is to provide a flow conductor assembly in which
the valve is biased toward its closed position and which is movable
to open position by means controllable from the surface.
A still further object is to provide a flow conductor assembly
having a flow passage through which a control fluid is conducted to
the valve from the surface wherein the valve is moved to open
position by increasing the pressure of the control fluid at the
surface.
Still further object is to provide a flow conductor assembly which
permits movement of well tools therethrough into and from the
well.
Another object is to provide a well flow conductor assembly usable
in a well installation employed in the drilling of a well below a
body of water wherein the well installation provides a continuous
passage from above the surface of the water into the well and
wherein the valve of the flow conductor assembly is positioned near
the ocean floor when the well installation is positioned in the
well and being held by a blowout preventer which closes the
continuous passage about the well flow conductor assembly.
Still another object is to provide a flow conductor assembly
including a valve connectable to the top of a tubing which extends
into the well and a pair of telescoped concentric flow conductors
connected to the upper end of the valve, the inner flow conductor
conducting fluid being in alignment and communication with the
tubing when the valve is open and the telescoped conductors
providing a passage therebetween through which control fluid from
the surface is transmitted to the valve to open the valve.
Still another object is to provide a flow conductor installation
wherein the outer flow conductor is provided with a means
engageable by the blowout preventer of a well installation for
holding the flow conductor assembly against movement in the well
installation.
A further object is to provide a flow conductor assembly wherein a
connector head is connected to the upper ends of the telescoped
flow conductors and has passages communicating with the inner flow
conductor and the control fluid passage wherein the connector head
has means for detachably securing a large flow conductor thereto
for communication with the inner flow conductor and a small control
fluid flow conductor for communication with the passage provided by
the telescoped conductors.
A still further object is to provide a latch mandrel for a flow
conductor releasably engageable with a latch means of the flow
conductor when it is inserted downwardly and placed in
communication with the inner concentric flow conductor thereinto
and which is not releasable thereon except upon rotation of the
latch mandrel.
A still further object is to provide a latch mandrel and valve
assembly for the use with a second flow conductor which is
engageable with a latch means of the connector head wherein it is
inserted into another passage of the connector head and placed into
communication with the control fluid flow passage of the concentric
conductors and which is releasable therefrom only upon rotation
thereof.
Another object is to provide a new and improved guide usable with
the latch mandrel for orienting the latch mandrel and the latch
mandrel and valve assembly with the two passages of the connector
head.
Still another object is to provide a flow conductor assembly having
means a new and improved connector head usable in the flow
conductor assembly which is provided with latch means engageable
with latch mandrel to releasably secure the flow conductors
inserted therein against nonrotational displacement therefrom.
An important object of the invention is to provide a valve having a
housing in which a pair of balls provided with axial passages are
mounted, each of which is separately biased toward its closed
position and has an operator means for moving it to open position,
the housing having means for simultaneously conducting control
fluid under pressure to the two operator means to cause the balls
to be moved to their open positions.
Still another object is to provide a valve wherein each operator
means includes a piston and a piston member releasably secured to
the piston, the piston member being biased upwardly to hold the
ball in closed position, the ball being moved to open position when
the pressure thereabove exceeds the pressure therebelow by a
predetermined value sufficiently great to release the piston member
from the piston and overcome the force biasing the piston member
upwardly.
Still another object is to provide a valve wherein the housing is
provided with a flow passage through which control fluid under
pressure is transmitted to the piston to move the piston member and
therefore the ball to its open position against the force exerted
thereon by the means biasing the piston member.
A further object is to provide a new and improved guide for
orienting successively a large flow conductor and a small flow
conductor in alignment with the upper ends of the passages of a
connector head.
Additional objects and advantages of the invention will be readily
apparent from the reading of the following description of a device
constructed in accordance with the invention, and reference to the
accompanying drawings thereof, wherein:
FIG. 1 is a schematic illustration of a well installation with a
flow conductor assembly embodying the invention extending
therethrough;
FIG. 2 is an enlarged sectional schematic illustration showing an
intermediate portion of the flow conductor assembly in position in
the well installation;
FIG. 3 is a view similar to FIG. 2 being a continuation thereof
showing a lower portion of the flow conductor assembly;
FIG. 4 is a vertical, partly sectional view of the upper portion of
the valve of the flow conductor assembly;
FIG. 4A is a fragmentary enlarged view of a portion of the
valve;
FIG. 4B is an enlarged fragmentary view of another portion of the
valve;
FIG. 5 is a view similar to FIG. 4, being a continuation thereof
showing an intermediate portion of the valve;
FIG. 6 is a view similar to FIG. 5, being a continuation thereof,
showing the bottom portion of the valve;
FIG. 7 is an enlarged fragmentary sectional view of a portion of
the valve;
FIG. 7-A is a sectional view taken on line 7-A-7-A FIG. 5;
FIG. 8 is a vertical sectional view of the connector head of the
flow conductor assembly;
FIG. 9 is an enlarged sectional view taken on line 9-9 of FIG.
8;
FIG. 10 is a fragmentary side view of a latch mandrel connectable
in one passage of the flow conductor assembly;
FIG. 11 is an enlarged fragmentary, vertical, sectional view of the
valve of the connector head;
FIG. 12 is a vertical, partly sectional view of a latch mandrel and
valve assembly which is connectable in another passage of the
connector head;
FIG. 13 is a vertical, partly sectional, view of the guide and the
connector head of the flow conductor assembly showing the guide
mounted on the latch mandrel of a large flow conductor;
FIG. 14 is a schematic, partly sectional view showing a modified
form of the flow conductor assembly in the well installation;
FIG. 14a is a fragmentary, partly sectional view of a modified
connector head used in the flow conductor assembly of FIG. 14;
FIG. 15 is a vertical, partly sectional view of another modified
form of the flow conductor assembly in the well installation;
FIG. 15-A is a vertical, partly sectional, view of a connector head
of the flow conductor assembly illustrated in FIG. 15; and,
FIG. 16 is a vertical, partly sectional view of still another
modified form of the flow conductor assembly in a well
installation.
Referring now particularly to FIG. 1 of the drawing, the well
installation 30 at the bottom of a body of water, which is used
during the drilling of the well, includes a casing 31 which is
secured in the usual manner to a casing head 32, a stack of blowout
preventers 33 mounted on the casing head, a latch head 35 mounted
on the uppermost blowout preventer and a riser tube 36 releasably
connected to the upper end of the latch head and extending above
the surface of the water and through an aperture in a floating work
platform 37. This well installation provides a longitudinal
continuous passage 38 from above the surface of the water to the
well through which a flow conductor assembly 40 may extend and be
supported adjacent the bottom of the body of water by means of one
of the blowout preventers 33. The blowout preventers may be of any
well known and suitable type and be manually operable by divers or
may be remotely operated, as for example, hydraulically, in which
event the suitable control fluid lines would extend therefrom to
the work platform. Such blowout preventers have means for holding a
flow conductor which extends therethrough against movement and for
sealing therebetween. The flow conductor assembly includes a string
of tubing 44 which extends to any desired depth in the well and
which usually has a packer (not shown) for closing the annulus
between the tubing and the casing above a producing formation, a
valve 45 which controls flow of fluids through the string of
tubing, and a pair of concentric conductors 46 and 47 which provide
an annular passage 48 for the flow of control fluid for controlling
operation of the valve 45 connected to their lower ends. The lower
end of the inner conductor 47 is placed in communication with the
tubing string 44 when the valve 45 is opened. The flow conductor
assembly also includes surface flow conductors 49 and 50 and a
connector head 51 connected to the upper ends of the concentric
conductors. The lower ends of the surface conductors 49 and 50 are
releasably connected to the connector head 51 which establishes
communication between the large surface conductor 49 and the inner
flow conductor 47 and between the small or control fluid conductor
50 and the annular passage 48.
When the flow conductors 49 and 50 are to be secured to the
connector head which is already in the passage 38 below the surface
of the water, a guide 55 is secured to the large flow conductor 49
and is employed to properly orient the large flow conductor
relative to the connector head and also to orient the guide
relative to the connector head so that it will be in proper
position to guide the lower end of the small conductor properly to
the connector head for connection thereto.
In use, after the drilling operations have been completed and while
the drilling well installation 30 is still in place and it is
desired to perform short time production testing operations on the
well, the string of tubing is lowered in the well from the floating
working platform 37 by the usual well known equipment and,
sequentially, the valve 45 is connected to the upper end of the
string of tubing, the concentric flow conductors 46 and 47 are
connected to the upper end of the valve, the connector head is
connected to the concentric flow conductors and, if desired, the
large and small surface flow conductors are releasably connected to
the connector head as the string of tubing is lowered into place
through the passage 38 into the well.
When the string of tubing and the flow conductor assembly 40 are in
desired location in the well installation, at least one of the
blowout preventers is operated to engage the outer flow conductor
46 to hold it against upward or downward movement in the well
installation 30 and also to seal therebetween. Suitable surface
control equipment 60 is connected to the upper end of the large
flow conductor 49 to control the flow therethrough and the string
of tubing 44 and to permit introduction of well tools into and from
the large conductor 49.
Control fluid under pressure is supplied to the upper end of the
control fluid conductor 50 and the annular passage 48 between the
concentric conductors from a suitable control manifold 61 through a
conduit 62 to control operation of the valve 45. Tools may be run
through the flow conductor assembly and the tubing string to
perforate the casing at the location of the producing formation
and, if desired, cementing operations and the like may also be
performed by use of the flow control assembly and the tubing
string. The valve 45 is closed and opened as required by such
operations.
The production of well fluids from such earth formation may then be
tested by permitting their flow upwardly through the string of
tubing to the surface. The valve may be closed at any desired time
by decreasing the fluid pressure which is transmitted thereto from
the manifold 61.
If it is necessary to remove the conductors 49 and 50 and the riser
pipe 36 from the latch head, as due to the occurrence of storm
conditions at the location of the well, the valve 45 is closed and
the pipes 49 and 50 are then detached from the connector head as by
unscrewing them. The riser pipe is also detached from the latch
head. The working platform itself may either be left anchored in
place or removed prior to the arrival of the storm. The string of
tubing, the valve, the concentric flow conductors and the connector
head are now left supported in the well by the blowout preventer.
Since the water conditions at the bottom of the body of water are
always relatively quiet with little or no wave action, there is
little likelihood that the portions of the flow conductor assembly
left in the well will be damaged. The valve 45, which is below the
blowout preventers, will close the upper end of the tubing in the
event that the riser pipe and the flow conductor 49 and 50 are
damaged or broken away from the connector and latch head, as in the
event the work platform is struck by a vessel or a sudden storm or
unpredicted earthquake wave occurs. The latch head being of very
strong construction will in all likelihood not be broken away when
the riser pipe is so detached or broken away from it.
When the storm ceases of if for any other reason it is desired to
come back and reconnect the flow conductor 49 and 50 to the
connector head in order to perform further or additional operations
on the well, the floating working platform 37 is again positioned
over the well head assembly, the riser pipe 36 is connected to the
latch head 35 and preferably any water within the well head
assembly above the blowout preventer stack is removed, as by
pumping. The guide 55 is then mounted on the lowermost end of the
large flow conductor 49 and is lowered through the riser pipe. The
guide which includes a large tubular member 64 and a small tubular
member 65 will not permit connection of the flow conductor 49 to
the connector head 51 until the guide is so oriented relative to
the connector head that its small tubular member 65 is properly
positioned over the connector head to guide properly the small flow
conductor 50 to the connector head. The large surface flow
conductor is then connected to the connector head and subsequently
the small flow conductor is lowered through the riser pipe and
guided by the guide 55 to the connector head and again releasably
attached thereto. Further operations then may be performed through
the flow conductor assembly and the string of tubing, such as
further production testing, cementing and the like.
The valve 45 includes an elongate tubular mandrel 100 which
includes a top section 101 provided with internally threaded
section 103 into which the lower end of the inner flow conductor 47
is threaded and an internally threaded section 102 in which the
lower end of the outer flow conductor 46 is threaded.
The mandrel 100 also includes an upper cylinder section 137 whose
upper end is threaded on the reduced lower end portion of the top
mandrel section 101, an upper connector section 138 whose upper
portion is threaded into the lower portion of the upper cylinder
section 137, an upper operator section 139 whose upper reduced
portion is threaded on the lower reduced portion of the upper
connector section 138, a middle connector section 140 whose upper
portion is telescoped into the upper operator section 139 and is
threadedly secured into the lower end of said upper operator
section, a lower cylinder section 141 whose upper end is threaded
on the lower end of the middle connector section 140, a lower
connector section 142 whose upper end telescopes into the lower
cylinder section 141 and is threadedly secured thereto, a lower
operator section 143 whose upper end is threaded on the reduced
lower end portion of the lower connector section 142, and a bottom
section 144 which extends into the lower end portion of the lower
operator section and is threadedly connected therein. Each of the
mandrel sections may be held against rotation relative to the other
adjacent sections to which it is connected by means of set screws
145 and 146 which extend through end slots of one section into a
threaded bore of the other. The upper and middle connector sections
138 and 142 have seal assemblies, which may include an O-ring 148
and a backup ring 149 positioned in external recesses in said
sections and which seal between the connector sections and the
mandrel sections into which they telescope. The middle connector
section 140 also has a similar seal assembly which seals between it
and the upper operator section 139, and the bottom mandrel section
144 has a similar seal assembly which seals between it and the
lower operator section.
The top mandrel section 101 is provided with one or more vertical
upwardly opening longitudinal passages 105 whose lower ends open
through transverse bores 106 to an annular passage 107 between the
mandrel 100 and an external sleeve 109 whose upper end portion is
threaded on the reduced middle portion 110 of the top mandrel
section. The upper end of the passage 107 is closed by a seal
assembly 112, which engages the external surface 114 of the
midportion of the top mandrel section below a downwardly facing
annular shoulder 115 formed thereon and the internal surface 117 of
the sleeve 109 above an upwardly facing shoulder 118 therein. The
seal assembly may include an O-ring 113, a backup ring whose
downward movement is limited by its engagement with the shoulder
118, a pair of backup rings on either side of the O-ring, and a
thrust ring whose upward movement is limited by its engagement with
the shoulder 115. The lower end of the annular passage 107 is
similarly closed by a seal assembly 125 whose O-ring 126 engages
the external surface 127 of the lower cylinder section 141 of the
mandrel and the internal surface 128 of the sleeve below its
internal annular shoulder 129. The seal assembly includes an upper
backup ring 131 whose upward movement is limited by its engagement
with the sleeve shoulder 129, a pair of backup rings on either side
of the O-ring, and a thrust ring whose downward movement is limited
by its engagement with the upwardly facing end surface or shoulder
135 of the seal assembly retainer member 136 threaded into the
lower end of the sleeve 109.
The ball valve 150 is pivotally mounted in the lower operator
mandrel section 139 by means of pins 151 whose outer portions are
rigidly secured in suitable lateral bores 152 in the wall of the
upper operator section 139 and whose inner portions extend into
slots 153 of the ball. The engagement of the pivot pins 151 with
the surfaces of the ball defining the slots which extend angularly
relative to the central axis of the ball causes the ball to rotate
substantially 90.degree. from its open position wherein its axial
passage 155 extends longitudinally relative to the mandrel and a
closed position wherein its passage 155 extends transversely
relative to the longitudinal axis of the mandrel when the ball
valve is moved upwardly a predetermined distance in the housing.
The valve is moved between its lower open position and its upper
closed position by an operator assembly 160 which includes a piston
161, a tubular piston member 162 whose upper end is connected to
the piston, a tubular housing 163, upper and lower annular seats
164 and 165 disposed above and below the ball, and a pair of
cooperative upper and lower locking rings 166 and 167 which hold
the ball and the seats against displacement from the housing.
The tubular piston 161 includes a tubular upper extension 171 which
extends upwardly into the top mandrel section 101 and on which are
mounted two seal assemblies 175 which seal between external
surfaces 173 of the upper extension and the internal surface 174 of
the top mandrel section. Each of the assemblies may include a
plurality of pressure sensitive type packing rings for sealing in
both upward and downward directions as shown. Downward movement of
the upper seal assembly 175 is limited by the upwardly facing end
shoulder 176 of a retainer ring 177 whose downward movement is
limited by engagement of its internal downwardly facing annular
shoulder 178 with top surfaces of a plurality of ring segments 182
whose inner portions extend into an annular recess 183 of the
piston extension. Upward movement of the upper seal assembly 175 is
limited by the bottom annular shoulder 186 of a packing retainer
ring 185. The retainer ring 185 may be secured to the top end of
the packing extension in any suitable manner, as by means of pins
187 which extend through suitable lateral bores of the retainer
ring into the lateral bores of the piston extension. Upward
movement of the lower packing assembly on the piston extension is
prevented by a backup ring 179 whose top annular surface engages
the downwardly facing annular surfaces of ring segments 182 which
extend outwardly beyond the limits of recess 183. Downward movement
of the lower packing assembly on the piston extension 171 is
limited by the upwardly facing shoulder 180 of the piston extension
171.
The lower end of piston 161 has upper and lower packing or seal
assemblies 191 and 192 mounted thereon above and below its external
annular flange 193. The seal assembly 191 may include a plurality
of packer rings 194, a backup ring 195 which engages the top
annular shoulder 196 of the flange 193 to limit downward movement
of the packer rings, and a retainer ring 198 which limits upward
movement of the packer rings. The retainer ring is secured to the
piston by suitable pins 199 which extend through lateral apertures
of the retainer ring into lateral bores of the piston. The lower
seal assembly 192 similarly may include a plurality of packer rings
201 whose backup ring 202 engages the downwardly facing annular
shoulder 203 of the piston flange 193 to limit upward movement of
the packer rings on the piston. Downward movement of the packer
rings is limited by a retainer ring 205 secured to the piston by
pins 207 which extend through suitable lateral apertures of the
retainer ring into lateral bores of the piston.
The upper end of the tubular piston member 162 telescopes into the
enlarged lower portion of the bore of the piston and its upward
movement into the piston is limited by the engagement of its
annular external shoulder 211 with the downwardly facing internal
shoulder 212 of the piston. The piston member is held releasably
against downward movement relative to the piston by a split snap
ring 214 whose inner portions extend into an external annular
recess 215 of the tubular piston member and whose outer portions
extend into the internal annular recess 216 of the piston.
The snap ring has an upwardly and outwardly inclined outer cam
surface 217 whose engagement with the annular shoulder 217a of the
piston defining the lower end of the recess 218 when the piston
member is forced downwardly relative to the piston causes the snap
ring to contract and move inwardly into the recess 215 of the
piston member and thus release the piston member for downward
movement relative to the piston. The snap ring also has an upper
external downwardly and outwardly inclined shoulder 217b whose
camming engagement with the bottom end surface of the piston 161,
as the piston member is telescoped upwardly into the piston, causes
the snap ring to be moved resiliently inwardly into the recess 214
of the piston member. The snap ring moves resiliently outwardly
into the piston recess 216 when it moves into alignment
therewith.
The piston and the mandrel define an annular piston chamber 218
above the piston and below the bottom annular end surface 219 of
the top mandrel section. The annular passage 107 communicates with
the piston chamber 218 through one or more lateral ports 220 of the
upper piston section 137 of the mandrel.
The piston is biased upwardly by a pair of springs 221 and 222
disposed about the piston member in an annular spring chamber 223
between the piston member and the upper piston section 137. The
upper end portions of the springs abut the downwardly facing
annular shoulders 224 and 225 respectively, of a spring retainer
ring 227 rigidly secured to the piston member by a plurality of
screws 228 threaded in the lateral bores 229 of the spring retainer
and whose pin end portions extend into the apertures 231 of the
tubular member. The lower ends of the springs engage the top
annular shoulder 232 of the upper connector section 138.
Fluid may flow into and out of the spring chamber as the piston
moves upwardly and downwardly in the mandrel through a plurality of
ports 233 in the wal of the piston member.
The upper connector section 138 is provided with an internal
annular downwardly opening recess 235 in which is disposed a seal
assembly 236 which seals between the upper connector section and
the tubular piston member below the ports 233 thereof. Upward
movement of the seal assembly, which may include a plurality of
packing rings 237 is limited by the downwardly facing annular
shoulder 238 of the upper connector section and downward movement
thereof is limited by an annular seal retainer ring 240 threaded in
the lower enlarged end portion of the connector section. An O-ring
241 seals between the retainer ring and the upper connector
section. The seal assembly 236 prevents upward flow of fluids into
the spring passage and then inwardly into the tubular piston member
when the ball 150 is in closed position.
The housing 163 has an upper annular portion 245 which is
telescoped on the reduced lower portion 246 of the tubular piston
members 162 and is rigidly secured thereto in seal tight
relationship in any suitable manner, as by a weld 247. The upper
annular seat 164 is disposed in the downwardly facing annular
recess 250 of the housing and its upward movement in the housing is
limited by the engagement of its top shoulder with an internal
downwardly facing shoulder 252 of the housing. An O-ring 253
disposed in an upper external recess of the seat seals between the
upper seat and the housing. The upper seat may have an annular seat
ring 255 of a suitable hard surfaced low friction substance, such
as is commercially available under the names "Hostaloy" and
"Colmonoy," interposed between its internal annular arcuate surface
256 and the outer spherical surface of the ball 150. The seat ring
may be bonded or otherwise suitably secured to the seat.
The housing has a plurality of dependent resilient collet fingers
260 which extend below the ball 150 and are provided with internal
bosses 261 at their lower ends whose lower portions are received in
an annular upwardly facing recess 262 provided by the lock rings
166 and 167. Outward movement of the lower ends of the collet
fingers is limited by the engagement of the external surfaces of
the bosses 261 with the internal annular shoulder 263 of the
upwardly extending annular lock flange 266 of the lower locking
ring 167. Upward movement of the collet fingers relative to the
upper lock ring is limited by the engagement of the upper shoulders
of their internal bosses with the downwardly facing annular
shoulder 268 provided by the external annular flange 269 of the
upper lock ring.
The two lock rings are secured to one another by a plurality of
socket head cap screws 270 which extend upwardly through suitable
apertures in the lower lock ring into the downwardly opening
threaded bores 271 of the upper lock ring. Lock washers 272 are
interposed between the heads of the cap screws and the downwardly
facing shoulders provided by the downwardly opening bores 275 of
the lower lock ring in which the heads of the cap screws are
received.
Downward movement of the lower seat 165 is limited by the
engagement of its bottom surfaces 278 with the top surface 279 of
the upper lock ring 166. The lower seat has an internal upwardly
facing annular arcuate surface 280 to which is bonded or otherwise
suitably secured a seat ring 281 of a suitable low friction
material which engages the spherical outer surface of the ball 150.
The lower seat 165 is biased upwardly toward engagement with the
ball by a plurality of springs 284 disposed in a plurality of
downwardly opening circumferentially spaced bores 285 of the lower
seat. The upper ends of the springs engage the downwardly facing
surface defining the upper end of the bore and their lower end
portions engage the top surface 279 of the upper lock ring. The
upper and lower lock rings have pins 288 whose inner portions are
secured in suitable lateral bores of the lock rings and whose outer
portions extend outwardly into the longitudinal slots 289 between
the collet fingers 260 to engage the collet fingers and prevent
rotation of the lock rings relative to the housing 163. The pivot
pins 151 also extend to the recesses of the ball through two of the
longitudinal slots 289. It will be apparent that the upper and
lower seats, the ball and the upper lock ring 166 may be inserted
upwardly into the housing 163 between the collet fingers whose
lower end portions flex resiliently outwardly to permit such upward
movement of these components and then flex inwardly as the top
internal shoulders 267 of their bosses 261 move below the lower
shoulder 268 of the upper lock ring flange 269. The lower lock ring
is then moved upwardly to telescope its lock flange 266 about the
lower end portions of the collet finger bosses and is then secured
to the upper lock ring by the cap screws 270 thus locking the
collet fingers against outward movement.
Downward movement of the piston 162 and the housing is limited by
the engagement of the inclined downwardly facing shoulder 299 of
the lower lock ring 167 with the internal upwardly facing shoulder
290 of the middle connector section 140.
The lower ball 150a and its operatively and structurally associated
elements are similar in structure and mode of operation to the ball
150 and its operatively and structurally associated elements and,
accordingly, the elements associated with the lower ball have been
provided with the same reference numerals, to which the subscript
"a" has been added, as the corresponding elements operatively
associated with the upper ball 150. Fluid may flow between the
passage 107 and the piston chamber 218a above the piston 161a via
the ports 220a of the lower piston section 141. Downward movement
of the tubular piston 162a is limited by the engagement of the
shoulder 299a of the lower lock ring with the shoulder 290a of the
bottom mandrel section 144. The upward force exerted on the piston
162 by the springs 221 and 222 and the upward force exerted on the
piston 162a by the springs 221a and 222a and static pressure of
fluids in the conductor 46 acting upwardly through the ports 233
and 233a on the undersides of the pistons 161 and 161a are greater
than the static pressure of the fluids in the conductor 46 and in
the passage 48 between the conductors 46 and 47 acting downwardly
on such pistons so that the pistons will move upwardly and rotate
the balls to their closed positions when the fluid in the small
surface flow conductor is not maintained under pressure.
In use, when it is desired to open the two ball valves, the fluid
pressure in the passage 107 is increased, as by pumping from
control manifold 61, and when the downward force exerted on the
pistons 161 and 161a by the fluid pressure in the piston chambers
218 and 218a exceeds the total upward force exerted on the pistons
by the springs 221, 222, and 221a, any upwardly acting pressure
differentials across the balls and their pistons, and any
frictional resistance present in the system due to these forces,
the pistons will start to move downwardly. Continued pumping from
manifold 61 will cause the pistons to continue to move downwardly
until stopped by the engagement of the shoulders 289 and 289a of
the lower lock rings 167 and 167a with the respective upwardly
facing shoulders 299 and 299a of mandrel sections 140 and 144.
Continued pumping from manifold 61 will produce an immediate
pressure increase in the fluids being pumped and then may be seen
on a pressure gauge in the fluid line 62 on the surface. The
pressure required at the pistons 161 and 161a is approximately 10
percent greater than any well pressure acting to close the ball
valves. During the downward movement of pistons within their limits
of travel, the balls 150 and 150a rotate through substantially
90.degree. from a closed position wherein their axial passages 155
and 155a are out of alignment with the axial passages of the
housing, the tubular piston members, the pistons, and the mandrel,
to positions wherein they are in alignment with these axial
passages to permit fluid flow through the valve.
If the pressure in the passage 107 is decreased below the value at
which its force holds the pistons in their lower positions, the
force of the springs, and of any upwardly acting pressure
differential acting across the pistons and balls, moves the pistons
and the balls upwardly in the mandrel thus causing the balls to
rotate through substantially 90.degree. to positions wherein their
axial passages 155 and 155a extend transversely relative to the
longitudinal axis of the mandrel and the engagement of their outer
surfaces with the seat members 255 and 255a then prevents upward
flow of fluid through the mandrel.
Upward movement of the pistons 161 and 162 is limited by the
engagement of the shoulders 294 and 294a of the housings 163 and
163a with the shoulders 295 and 295a of the packer nuts 240 and
240a, respectively. Any upward pressure differential existing
across the balls now tends to hold them in sealing engagement with
the seat members. During the upward and downward movement of the
balls, the lower and upper seats 164 and 164a and 165 and 165a of
the two balls guide the rotational movement of the ball valves.
The balls when they are in their closed positions may be moved to
open positions either by increasing the pressure within the annular
passage 107 in the manner described above or by increasing the
pressure within the inner string of tubing 47, as by pumping
thereinto at the surface and therefore in the passage through the
tubular operator assembly 160 above the upper ball 150. When the
pressure within the inner tubing is increased to such value that
its force acting across the upper ball 150 and the upper piston 161
exceeds the force of the upwardly acting pressure differential
existing across the ball 150, the force of springs 221 and 222 and
the force of the snap ring 214, the ball valve is moved downwardly
and pulls the piston member 162 downwardly therewith, the camming
engagement of the external lower cam shoulder 217 of the snap ring
with the bottom shoulder 217a of the piston camming the snap ring
inwardly into the recess 215 to permit such downward movement of
the piston member relative to the piston. The piston is held
against downward movement since the pressure in the chamber 218 is
now considerably smaller than the pressure below the piston acting
upwardly on the piston through the ports 233 from the inner string
47. As more fluid is pumped into the inner string 47, the ball 150
is moved downwardly and at the same time is rotated to at least
partially open position admitting fluid pressure to the passage
through the lower tubular operator assembly 160a above the lower
ball 150wall The ball 150a and the piston member 162a are then
moved downwardly relative to the piston 160a and the ball 150a
rotates to at least partially open position. Once the two balls are
in at least partially open position, fluids may be pumped
downwardly through the valve and into the tubing 44 which is
connected to the lower end of the bottom mandrel section 144.
When the pumping is stopped and the pressure across the ball valves
tends to equalize the springs 221a and 222a move the tubular valve
member 162a and the ball 150a upwardly and the springs 221 and 222
move the tubular valve member 162 and the ball 150 upwardly back to
the positions illustrated in FIGS. 4, 5 and 6 of the drawings. As
the snap rings 214 and 214a move into alignment with the internal
recesses 216 and 216a of their associated pistons 161 and 161a, the
snap rings move resiliently outwardly thereinto to releasably hold
the piston members releasably secured to the piston. The engagement
of the upper cam shoulders of the snap rings with the bottom end
shoulders of the pistons of course cams the snap rings inwardly
into the external recesses 215 to permit such upward telescoping
movement of the upper end portions of the piston members into the
pistons.
It will be apparent that the two balls are mounted in
longitudinally spaced relation within the valve mandrel and in the
event one of the balls fails to function properly and close when it
is required to do so, that the other will close. The valve
embodying the invention is therefore used wherever it is essential
that flow through a flow conductor be stopped when this is
necessary, as for example, in well installations where failure of
the valve to close when a predetermined condition arises may cause
very costly damage.
It will further be seen that a common control fluid pressure will
operate both bails and that preferably the forces exerted by the
springs 221 and 222 and 221a and 222a on the two pistons are equal
so that both balls will tend to open when the fluid pressure within
the annular passage 107 increases to a first predetermined value
and will close when such pressure drops below a predetermined
value.
It will further be seen that the valve is of relatively simple
economical and compact construction even though it is provided with
two separate means for effecting closure of the valve for extreme
reliability of performance of the valve.
Referring now particularly to FIG. 8, the connector head 51
includes a tubular latch housing 301 whose upper end is threaded
into the enlarged lower portion 302 of the central passage 303 of a
latch head 304. The latch head has an internal annular flange 305
which provides a downwardly facing annular stop shoulder 306, a
lower upwardly and inwardly extending annular cam shoulder 307 and
an upper upwardly and outwardly extending annular stop shoulder
308. The lower end of the latch housing is threaded in the enlarged
upper portion 309 of a tubular connector sub 310. A tubular latch
retainer 312 is mounted within the latch housing against
longitudinal movement therein, its lower end being threaded in a
retainer bushing 314 whose bottom external annular flange 315 is
disposed below the annular lower end shoulder 316 of the latch
housing and the annular upwardly facing shoulder 317 of the
connector sub. The latch retainer has an external annular flange
319 at its upper end portion which is provided with a plurality of
circumferentially spaced upwardly opening slots 320. The upper end
of the external latch retainer flange is beveled or inclined
upwardly and inwardly.
A latch 325 is mounted in the latch housing for limited
longitudinal movement relative thereto and includes a base ring
326, a plurality of circumferentially spaced resilient collet or
latch fingers 328 integral with and extending upwardly from the
base ring and into the slots 320 of the external flange 319 of the
latch mandrel. Each of the collet fingers is provided with internal
longitudinally extending bosses 330 provided with thread teeth 331.
The thread teeth have bottom surfaces 332 which extend
substantially horizontally or perpendicularly to the longitudinal
axis of the latch housing and with downwardly and inwardly
extending upper shoulders or surfaces 333. Downward movement of the
latch 325 is limited by the engagement of the bottom end surface of
its base ring 326 with the annular top surface or shoulder 335 of
the retainer bushing 314. The upper ends of the collet fingers are
spaced below the cam shoulder 307 of the latch head when the latch
325 is in its lowermost position. When the latch head is moved
upwardly in the latch housing, the upwardly and inwardly extending
upper external cam shoulders 337 of the latch fingers move into
engagement with the cam shoulder 307, and this camming engagement
of the shoulders 337 and 307 will tend to cause the upper ends of
the latch fingers to move inwardly. A seal assembly 340 is disposed
in the connector sub and may include a plurality of packer rings
341 disposed between upper and lower adapter rings 342 and 343.
Upward movement of the seal assembly is limited by the engagement
of the top surface of the upper adapter ring with the bottom end
surface of the retainer bushing 314 and its downward movement is
limited by the engagement of the lower adapter ring with the
upwardly facing annular shoulder 344 of the connector sub. The
connector sub 310 is provided with an internal annular flange 346
which provides upper and lower stop shoulders 347 and 348. The
upper end of the inner concentric flow conductor 47 is threaded in
the reduced internally threaded portion 349 of the bore of the
connector sub and the outer concentric flow conductor 46 is
threaded in the lower enlarged internally threaded portion 350 of
the connector sub. The connector sub has a lateral port 353 which
opens to the bore of the connector sub through the shoulder 351 to
the upper end of the annular passage 48 between the concentric flow
conductors.
A latch mandrel 360 is connected to the lower end of the large flow
conductor 49 to constitute its lower end portion by means of
internal threads in its upper end portion. The lower end portion of
the latch mandrel is telescopable downwardly through the central
passage 303 of the latch head 304 into the latch housing and has
external threads 362 which are engageable with the threads 331 of
the latch fingers. The upper shoulders or surfaces 363 of the
threads 362 extend substantially perpendicularly to the
longitudinal axis and their lower surfaces 364 extend upwardly and
outwardly. When the lower end of the latch mandrel is inserted
through the passage 303 of the latch head the reduced portion 365
of the latch mandrel below the threads 362 moves past the latch
finger threads and thereafter the lower shoulders 364 of the teeth
of the latch mandrel engage the upper surfaces 333 of the teeth 331
of the latch fingers and cam the upper ends of the latch fingers
outwardly to permit further downward movement of the latch mandrel.
When the downward telescoping movement of the latch mandrel is
arrested due to the engagement of its annular stop shoulder 367
with the upper stop shoulder 308 of the latch head, the latch
mandrel teeth 362 are in threaded engagement with the teeth 331 of
the latch fingers and the seal assembly 340 sealingly engages the
reduced portion 365 of the latch mandrel to seal between the
connector sub 310 and the latch mandrel 360. Due to the provision
of the substantially horizontal bottom surfaces 332 of the latch
finger teeth and similar top surfaces 363 of the latch mandrel
teeth 362, upward nonrotational movement of the mandrel relative to
the latch cannot now take place. Any upward movement of the latch
mandrel will now cause the latch 325 to move upwardly and as the
cam shoulders 337 of the latch fingers engage the internal cam
shoulder 307 of the connector head, their camming engagement tends
to force the upper ends of the latch fingers inwardly and prevents
disengagement of the latch mandrel from the connector head except
by rotation thereof relative to the connector head and therefor to
the latch 325 which is held against rotation by the retainer 312
into whose slots 320 extend the internal bosses 330 of the latch
fingers.
The latch head 304 has a vertical bore 370 radially spaced from its
longitudinal axis in which is rigidly secured an elongate housing
371 which includes an upper latch section 372, an intermediate
connector section 373 and a valve housing section 374. The
connector section has an upper portion 376 which is threaded in the
lower end of the latch housing section 372 and an external
intermediate flange whose downwardly facing annular shoulder 379
engages an internal upwardly facing annular shoulder 380 of the
connector head to limit downward movement of the connector section
in the bore 370. The connector section has an externally threaded
intermediate portion 382 which is secured to the internally
threaded portion 383 of the latch head 304 below its shoulder
380.
A latch retainer 312a and a latch 325a mounted in the elongate
housing are similar in structure and operation to the retainer 312
and the latch 325 and, accordingly, have been provided with the
same reference characters, to which the subscript "a" has been
added, as the corresponding elements of the latch retainer 312 and
the latch 325, respectively. Downward movement of the latch 325a in
the latch housing section 372 is limited by the engagement of its
base ring 326a with the top end surface or shoulder 385 of the
connector housing section 373. The lower externally threaded end
portion of the retainer 312a is threaded in the enlarged threaded
upper end portion of the central bore or passage 388 of the
connector housing section. Upward movement of the latch 325a is
limited by the engagement of the cam shoulders of its latch fingers
328a with the annular upwardly and inwardly extending cam shoulder
307a of the latch housing section 372. The connector housing
section has an internal annular flange 390 which provides an upper
stop shoulder 391 and a downwardly facing stop shoulder 392.
A seal assembly 394 is disposed in the bore 388 of the connector
housing section below the flange shoulder 392 and may include a
plurality of packing rings 395 disposed between a pair of upper and
lower adapter rings 396 and 397. Upward movement of the seal
assembly is limited by the engagement of the upper adapter ring
with the stop shoulder 392 and its downward movement is limited by
the engagement of the lower adapter ring with a retainer ring 398
whose upward movement in the bore 388 is limited by the engagement
of its top surface with the downwardly facing annular shoulder 399
of the connector housing section. The top end surface of the valve
housing section 374, which is threaded in the lower portion 400 of
the connector housing section, limits downward movement of the
retainer ring 398. The valve housing section 374 is provided with
an external outer recess in its upper end portion in which an
O-ring 401 is disposed and seals between the valve and connector
housing sections.
A valve 402 is mounted in the valve housing section for controlling
flow of fluids through the passage 388 and thus through the housing
371 and includes elongate tubular body 404 which is biased upwardly
toward closed position by a spring 405 disposed about the valve
body. The lower end portion of the spring bears against the bottom
upwardly facing shoulder or surface 406 of the valve housing
section 374 and its upper end portion bears against the bottom
annular shoulder of an external annular flange 408 of the valve
body.
The valve body has an upper reduced externally threaded end portion
410 on which is threaded the lower end portion of a check valve
housing 411. An O-ring 413 disposed in an external annular recess
of the valve body seals between the check valve housing and the
valve body. A check valve 412 mounted in the housing is biased
downwardly into engagement with the annular seat surface 414 of the
valve body by a spring 415. The stem 416 of the check valve extends
upwardly of the check valve housing through an aperture on its top.
The spring bears against an annular upwardly facing shoulder of the
check valve and a downwardly facing shoulder of the check valve
housing. The check valve when in its lower closed position in
seated engagement with the seat 414 prevents flow from the lateral
ports 417 of the check valve housing into the upper portion of the
central passage 418 of the valve body above the lateral ports 419
which communicate with the passage 418 and which extend through the
flange 408 thereof. The engagement of the upper surface of the
flange 408 with the ring 398 limits upward movement of the valve
body in the housing. When the valve 402 is in its upper position in
the body, the seal assembly 394 sealingly engages the check valve
housing 411 and thus closes the housing passage to flow of fluids
therethrough.
The downwardly opening port 422 in the bottom of the valve housing
section 374 is in communication with the port 353 of the connector
sub 310 through a conduit 424 whose opposite ends are connected to
the valve housing section and the connector sub by means of
suitable fittings or connectors 425 and 426 threaded into the outer
threaded portions of the ports 422 and 363. The check valve 412
when in its upper position will of course permit flow of fluids
upwardly therethrough from the passage 418 when the pressure in the
housing section below the seal assembly rises to permit escape of
fluids from the housing and thus from the passage 48.
A latch mandrel and valve assembly 430 (FIG. 12) connectable to the
lower end of the small surface flow conductor 50 by a connector
guide 431, is telescopable downwardly into the upper end of the
housing 371 and includes a latch mandrel 432 provided with external
threads 433 whose lower upwardly and outwardly inclined surfaces
434 are adapted to engage the upper downwardly and inwardly
inclined surfaces or shoulders 333a of the teeth 331a and cam the
resilient latch fingers 328a outwardly to permit downward movement
of the threads relative to the teeth and whose substantially
horizontally extending shoulders 435 adapted to engage the
substantially horizontally extending bottom shoulders or surfaces
332a of the teeth 331a to prevent upward movement of the latch
mandrel relative to the latch 325a. The upper ends of the latch
fingers 328a are cammed resiliently outwardly during downward
movement of the threads 433 therepast and then move resiliently
inwardly to engage the threads 433 to prevent upward nonrotational
movement of the assembly 430.
A valve housing 438, threaded on the lower reduced end portion 439
of the latch mandrel 432, has a reduced lower portion 441 which is
engageable by the seal assembly 394 and a downwardly facing stop
shoulder 440 which is engageable with the stop shoulder 391 of the
flange 390 of the connector 373 to limit downward movement of the
latch mandrel and valve assembly in the housing 371. A valve 442
slidably mounted in the housing 438 has an external annular recess
in which is disposed an O-ring 444 which sealingly engages with the
internal seal surface 445 of the valve housing 438 when the valve
is in its lower closed position wherein its downward movement is
stopped by the engagement of its downwardly facing annular shoulder
447 with the internal upwardly facing annular shoulder 448 of the
housing 438. The valve is biased to its lower position by a spring
449 whose lower end engages the top annular shoulder of an external
annular flange 451 of the valve and whose upper end portion engages
the downwardly facing annular end surface or shoulder 452 of the
latch mandrel 432. The spring extends about a tubular upper
extension 454 of the valve. The flange 451 is provided with
longitudinal slots 455 and the tubular extension is provided with
lateral ports 456 opening to the slots to facilitate flow through
the valve housing when the valve is in its open position.
The valve has a downwardly extending reduced or rod portion 458
whose bottom end is adapted to engage the top end of the stem 416
of the check valve 412 as the tubular body 432 is telescoped
downwardly into the elongate housing 371 and after the reduced
lower end portion 441 of the valve housing has moved into sealing
engagement with at least the upper portion of the seal assembly 394
so that very little fluid which might be present in the passage 388
of the elongate housing 371 above the check valve housing 411 will
be permitted to flow downwardly. Since the spring 449 which biases
the valve 442 downwardly is weaker than the spring 405 which biases
the valve 402 upwardly, the valve 442 will be moved upwardly to its
open position before the lower end surface of the valve housing 438
engages the top surface of the check valve housing 411 to permit
upward flow of fluid which may be trapped in the passage 388
between the lower end of the valve housing 438 and the check valve
housing 411.
The large and small vertical tubular members 64 and 65 of the guide
55 are rigidly connected to one another by a bottom plate 451, an
intermediate plate 452 and an inclined top plate 453. The large
tubular member extends through the aligned apertures 455, 456 and
457 of the plates with the lower end portion of the large tubular
member extending below the lower bottom plate 451 and with its top
surface coplanar with the top surface of the inclined top plate.
The small tubular member 65 similarly extends through aligned
apertures 459, 460 and 461 of the bottom, middle and top plates
with its bottom surface being coplanar with the bottom surface of
the bottom plate and with its top surface being coplanar with the
top surface of the inclined top plate.
Vertical plates 464 and 465 extend radially outwardly from the
large and small tubular members between the top and intermediate
plates respectively and vertical plates 466 and 467 whose bottom
edges rest on the bottom plate extend radially outwardly from the
large and small tubular member respectively. These components of
the guide are secured to one another by welding.
The guide is releasably securable to the latch mandrel 360 by one
or more pins 470 threaded in suitable lateral bores 471 of the
large tubular member 64 whose inner portions are receivable in the
annular external recess 474 of the latch mandrel 460. The latch
mandrel 360 also has a pair of vertical external slots 475 in which
the pins are receivable and which open upwardly to the recess
474.
Upward movement of the guide on the latch mandrel is limited by the
engagement of the pins with the upwardly facing surfaces 477 of the
latch mandrel defining the lower ends of the slots and downward
movement of the guide on the latch mandrel is limited by the
engagement of the pins with the downwardly facing annular shoulder
478 defining the upper end of the latch mandrel recess 474.
When the large flow conductor 49 is to be connected to the
connector head 51 which is already in place in the latch head 35 of
the well installation 30, the latch mandrel 360 is secured to the
lower end of the large flow conductor and inserted into the large
tubular member 64 of the inner guide, and the pins 470 are then
rotated to move their end portions inwardly into the recess 474 of
the outer concentric conductor 46. The guide is then supported on
the latch mandrel as the large flow conductor is lowered downwardly
through the riser pipe 36. The guide now holds the large flow
conductor centered within the riser pipe so that it will be aligned
vertically with the passage 303 of the latch head 304. If the small
tubular member 65 of the guide is not properly aligned with the
upper latch section 372 of the elongate housing 371 of the
connector head, downward movement of the guide is arrested by the
engagement of the top end shoulder of the elongate housing with the
bottom plate 451 of the guide. The large flow conductor and the
latch mandrel can then continue downward movement relative to the
guide and to the connector head until the pins 470 engage the
shoulder 478 of the latch mandrel. At this time the latch mandrel
is in the position illustrated in FIG. 13 relative to the connector
head with its threads 362 located above the connector head so that
the latch mandrel cannot be connected to the connector head 51. The
large flow conductor is then raised and rotated until the pins 472
are received in the upper ends of the slots 475 of the latch
mandrel. Rotation of the large pipe is continued until the small
tubular 372 moves into vertical alignment with the latch section
whereupon the guide moves by gravity downwardly until its downward
movement is arrested by the engagement of the bottom end surface of
the large tubular member 64 with the top surface of the latch head
304 or by the engagement of the pins 470 with the latch mandrel
shoulder 478. The latch mandrel can then move downwardly through
the passage 303 and its threads 362 engage the teeth 331 of the
bosses 330 of the fingers of the latch 325. The downward movement
of the latch mandrel and therefore of the large flow conductor 49
is then arrested due to the engagement of the latch mandrel
shoulder 367 with the shoulder 308 of the latch head 304.
It will thus be seen that the guide is used both to align the latch
mandrel and large flow conductor with the passage 303 of the latch
head 304 of the connector head and also to properly orient the
small tubular member 65 of the guide with the elongate housing 371
of the connector head so that when the latch mandrel and valve
assembly 430 connected to the lower end of the small flow conductor
50 are thereafter lowered through the riser pipe, the inclined
plate 453 will guide the lower end of the latch mandrel and valve
assembly into the upper end of the small tubular member 65 and
therefore into alignment with the upper end of the upper latch
section of the elongate housing 371. The latch mandrel and valve
assembly will then telescope into the upper end of the elongate
housing and be secured thereto by the engagement of the threads 433
thereof with the teeth 331a of its latch 325a. As the valve housing
438 moves downwardly through the passage 388, the bottom end of its
valve rod 458 engages the top end of the stem 416 of the check
valve 412 and the valve 442 is moved to open position as the valve
housing continues to move downwardly. The bottom end of the valve
housing then engages the top end of the check valve housing
whereupon the continued downward movement of the valve housing
moves the valve 402 downwardly against the resistance of the spring
405. As the check valve housing moves out of sealing engagement
with the seal assembly 394, the reduced end portion 441 of the
valve housing moves into engagement with the seal assembly.
Communication is now established between the lower end of the
passage 388 and the central longitudinal passage of the latch
mandrel and valve assembly 430.
Such downward movement of the latch mandrel and valve assembly 430
continues until the shoulder 440 of the valve housing 438 engages
the internal shoulder 391 of the connector sub. At this time the
threads 433 of the latch mandrel are in full engagement with the
threads 331a of the latch 325a and this engagement of the latch
mandrel threads and the latch threads now prevents nonrotational
upward movement of the latch mandrel from the elongate housing 371.
The latch mandrel may then be disconnected only by rotating the
latch mandrel to unscrew its threads out of engagement with the
thread teeth of the latch fingers of the latch 325a.
In use, after the well has been drilled and the well installation
30 which has been used in drilling the well, including the drilling
phase stack of blowout preventers 33, is still in place, the string
of tubing 44 is made up and lowered into the well installation 30
through the riser pipe 36 and the latch head 35. As the tubing
string is lowered into the well installation the upper end of the
string of tubing is threaded into the lower threaded portion 294 of
the bottom section 144 of the mandrel 100 of the valve 45, and the
lower ends of the inner and outer concentric conductors 47 and 46
are threaded into the threaded portions 103 and 102, respectively,
of the top section 101 of the mandrel and their upper ends are
threaded in the internally threaded portions 349 and 350,
respectively, of the connector sub 310 of the connector head 51.
The large flow conductor 49 is then releasably secured to the
connector head by the latch mandrel 360 which is secured to its
lower end and similarly the small or control fluid conductor 50 is
secured to the connector head by means of the latch mandrel and
valve assembly 430 which is secured to its lower end by the guide
connector 431. A suitable fluid, such as a light oil, is introduced
into the passage 105 of the valve 45, the passage 48 provided by
the concentric flow conductors, the tube 425 and the small flow
conductor 50 as these components are connected to one another. This
assembly of the tubing string 44, the valve 45, the concentric
conductors 46 and 47, the connector head 51 and the large and small
flow conductors 49 and 50 is lowered to a position wherein the
external annular recess 500 of the outer concentric flow conductor
46 is aligned with one of the blowout preventers 33. Such blowout
preventer 33a may be any suitable type, as for example the type
illustrated on Pages 1134 through 1140 of the Composite Catalogue
of Oil Field Equipment and Services, 1964--65 Edition, published by
World Oil, Houston, Texas, which has a pair of rams 501 and 502
which are movable toward each other and each is provided with
resilient seal elements 503. The rams are adapted to engage the top
and bottom shoulders 504 and 505 respectively of the outer
concentric conductor 46 defining the recess 500 when in operative
engagement with the outer conductor to prevent either upward or
downward movement of the outer concentric flow conductor 46. Others
of the blowout preventers 33, such as the blowout preventer 33b,
may be of the type illustrated on Pages 2575--2579 of the Composite
Catalogue, which employ a contractor piston 510 to urge an annular
sealing element or packing 511 into sealing engagement with a flow
conductor, such as the outer flow conductor 46 to seal therebetween
and close the passage 38. The blowout preventers are now operated
to close the annular passage or annulus 38 and also hold the outer
flow conductor against longitudinal movement.
Any desired production testing operations may now be performed
using the well installation 30 previously used to drill the well.
For example, various well tools may be moved downwardly through the
large flow conductor 49, after the valve 45 has been opened by
maintaining the pressure of the control fluid by means of the
manifold 81 and the conduit 62 connected to the upper end of the
control conductor 50. The rate of flow and volume of flow of the
well fluids into the well through perforations in the casing may
then be tested by permitting them to flow upwardly through the
string of tubing to the surface. If it is desired or necessary to
pump fluids, such as cement, acid or the like, into the well
through the string of tubing, the balls of the ball valve may be
maintained in open position by maintaining proper fluid pressure
from the manifold 61 to the valve 45 or, if such pressure is not
available, by pumping downwardly into the large flow conductor into
the passages of the operator assemblies 160 and 160a of the ball
valve 45 in the manner described above.
If it is necessary or desirable to disconnect the flow conductors
49 and 50 from the connector head and the riser pipe 36 from the
latch head 35 due to the occurrence of the storm conditions, before
any such desired operations have been completed, the pressure
manifold is operated to relieve or remove the pressure in the small
flow conductor 50, which causes the valve 45 to close. The large
flow conductor 49 is rotated to cause the threads 362 of its latch
mandrel 360 to unscrew from the thread teeth 331 of the latch 325
of the connector head, and then similarly the small flow conductor
50 is rotated to cause the teeth 433 of its latch mandrel 432 to
disengage from the teeth 331a of the latch 325a. As the latch
mandrel and valve assembly 430 on the lower end of the small flow
conductor is moved upwardly from the elongate housing 371 of the
connector head, the valve body 404 moves upwardly to closed
position so that no salt water may then flow downwardly thereinto.
Once the two flow conductors 49 and 50 are removed from the well
installation, the riser pipe may also be disconnected from the
latch head 35.
The tubing 44 is thus left supported in the well by the blowout
preventers. The valve now prevents any water from flowing into the
tubing and prevents any of the well fluids from flowing upwardly
out of the tubing.
If it is thereafter desired to reconnect the large and small flow
conductors to the connector head in order that any such interrupted
operations may be completed or others initiated, the latch head 360
is inserted through the large tubular member 64 of the guide 55,
and the pins 470 are then rotated to move their inner end portions
into the annular recess 474 of the latch mandrel 360. The pins are
preferably moved into the slots 475 so that during the lowering of
the latch mandrel and the large flow conductor 49, the guide is in
its lowermost position on the latch mandrel. The guide 55 holds the
large flow conductor centralized within the riser pipe 36 during
the lowering thereof through the riser pipe to the connector head
and holds the latch mandrel in position wherein its lower end is
aligned with the passage 303 of the connector head 51 and will
enter thereinto. If the small tubular member 65 is not aligned with
the upper latch section 372 of the elongate housing 371 of the
connector head 51, the bottom plate 451 of the guide engages the
top of the latch section and downward movement of the guide is now
arrested. Continued downward movement of the large flow conductor
and the latch mandrel 360 will then cause the lower reduced portion
365 of the latch mandrel to enter into the passage 303 of the latch
head 304 of the connector head 351. The engagement of the pins 470
with the top shoulder 478 of the latch mandrel defining the upper
end of the recess 474 then stops further downward movement of the
latch mandrel before its threads 362 enter into the passage 303 and
into engagement with the thread teeth 331 of the latch fingers of
the latch 325. An upward force then imparted to the large flow
conductor causes it to move upwardly relative to the guide. The
large flow conductor is rotated as it is moved upwardly to cause
the inner ends of the pins to be received in the upper ends of the
slots 475. Once the pins are received in the slots, rotation of the
large flow conductor will also cause rotation of the guide and, as
the guide is rotated and its small tubular member 65 moves over and
into alignment with the elongate housing 371, the elongate housing
will no longer support the guide and the guide will drop down, the
small tubular member 65 telescoping over the upper latch section
372. The guide is then supported on the latch head 304 of the
connector head by engagement of the bottom and shoulder of its
large tubular member 64 therewith or is then supported on this
latch mandrel 360 by the engagement of the inner portions of its
pins 470 with the shoulder 478 of the latch head 360 defining the
upper end of the recess 474.
The large flow conductor is then lowered and the threads 362 of the
latch mandrel engage the teeth 331 of the latch 325 so that the
large flow conductor and latch mandrel is then rigidly connected to
the latch head against upward nonrotational movement. At this time
the guide rests on the latch head 304 due to the engagement of the
bottom end shoulder of the large tubular member 64 with the latch
head.
The latch mandrel and valve assembly 430 is then connected to the
lower end of the small flow conductor 50 and is lowered through the
riser pipe. The small flow conductor is preferably filled with a
suitable fluid, such as light oil, after the latch mandrel and
valve housing assembly is connected to its lower end. When the
lower end of the valve housing 438 moves into engagement with the
top inclined plate 453 of the guide at any location above the upper
end of the small tubular member 65, the top plate guides the valve
housing toward the upper end of the small tubular member and when
it moves into alignment therewith, the latch mandrel and valve
assembly moves downwardly therethrough and is guided thereby into
the central 388 of the elongate housing 371. As the latch mandrel
and valve assembly t0 downwardly through the elongate housing 371,
the valve 442 is in the valve housing 438 is opened when it moves
into engagement with the valve stem 416 of the check valve 412 and
the reduced lower end portion 441 of the valve housing moves into
sealing engagement with the seal assembly 394 and then moves the
valve body 404 downwardly so that the check valve housing 411 moves
out of sealing engagement with the seal assembly 394. Fluid
communication is therefore now established between the lower end of
the small flow conductor 50 and the annular passage 48 provided by
the concentric flow conductors 46 and 47 and therefore with the
passage 107 of the valve 45 through the valve housing section 404
and the tube 424.
Any desired well operations can now again be performed, the valve
45 being opened and closed as required by controlling the fluid
pressure transmitted through the small flow conductor 50 to the
valve 45.
If it is thereafter again desired to detach the large and small
surface conductors 49 and 50 from the connector head, the small
flow conductor is first rotated to unscrew the threads 433 of its
latch mandrel 432 from the thread teeth 331a of the latch 325a.
After the small flow conductor has been removed from the well, the
large flow conductor is rotated to disengage the teeth 362 of its
latch mandrel 360 from the teeth 331 of the latch 325 whereupon the
large flow conductor 49 may be removed to the surface. As the large
flow conductor and latch mandrel 360 move upwardly from the
connector head the pins 470 engage either the bottom shoulder 479
defining the lower end of the annular recess 474 thereof or the
shoulders 477 defining the lower ends of the slots 475. The guide
is thus moved upwardly with the latch mandrel to the surface.
It will be apparent that once the string of tubing 44, the valve 45
and the concentric flow conductors 46 and 47 are positioned in the
well and held by the blowout preventers 33, the large and small
surface flow conductors may readily disconnected therefrom and
reconnected thereto as required leaving the valve positioned below
the blowout preventers, and the ball valve keeps the upper end of
the string of tubing closed to flow of fluids therethrough when the
small flow conductor is not connected to the connector head. The
blowout preventers of course close the passage 38 of the well
installation 30 about the outer concentric flow conductor 46.
Referring now particularly to FIG. 14 and 14a, the large and small
flow conductors may be connected to the inner and outer concentric
flow conductors 47 and 46 by means of a connector head 509. The
lower end of the large flow conductor 49 is threaded into the upper
internally threaded portion 501 of the connector head and the lower
end of the small flow conductor 50 is threaded in the upper
threaded portion 502 of a passage 504 of the connector head which
opens to the interior of the head at the internal annular shoulder
505 thereof between the threaded portions 507 and 508. The inner
concentric flow conductor 47 has its upper end threaded in the
threaded portion 507 of the head and the outer concentric conductor
46 has its upper end threaded in the lower threaded portion 508 of
the head. Control fluid may flow into the annular space 48 between
the concentric conductors through the small flow conductor and the
passage 504 of the head and thence to the valve 45.
It will be apparent that in the event storm conditions arise or it
is necessary to quickly disconnect the surface flow conductors 49
and 50 from the head 509, the conductors 49 and 50 must be
unscrewed from the connector head, and thereafter it will be
necessary to pull the head 509, the concentric flow conductors and
the string of tubing to the surface to enable the flow conductors
49 and 50 to be threaded into the head.
Referring now to FIG. 15, the concentric flow conductors 46 and 47
may have additional sections 46a and 47a, respectively, connected
thereto to extend to the surface with the uppermost sections 46a
and 47a being connected to a head 510. The topmost section of the
outer flow conductor 46 is threaded in the lower threaded portion
511 of the head and the uppermost section of the inner concentric
flow conductor 47 is threaded in the threaded portion 513 of the
head. The large flow conductor 49 is threaded in the upper threaded
portion 514 of the head and the conduit from the manifold is
threaded in the outer threaded portion 515 of the passage 516 which
opens to the annular passage between the inner and outer concentric
flow conductors. The control fluid is thus transmitted to the valve
45 through the annular passage 48 of the concentric flow conductors
which extends above the working platform.
Referring now to FIG. 16, if the well installation 30a has its
stack of blowout preventers 33 above the surface of the water, the
platform being permanently secured to the earth below the water,
the outer flow conductor 46 provided with an annular recess 500 may
be connected to the valve 45 by a plurality of sections 46a and to
the head 510 by one or more sections 46b. Similarly, the inner flow
conductor 47 may be comprised by a plurality of sections connected
by suitable couplings. The inner and outer flow conductors, the
ball valve 45, and the string of tubing 44 will of course be held
by the blowout preventers 33 and the control fluid from the
manifold will be transmitted to and from the valve through the
concentric annular passage 48 between the two flow conductors.
It will be apparent that in each of the installations described,
the valve is positioned at a location near the bottom of the body
of water so that if any damage occurs to the installation above the
well, the valve will automatically close, or "fail safe," to
prevent flow of well fluids through the string of tubing.
It will now be apparent that a new and improved apparatus has been
illustrated and described for performing various operations in a
well which utilize the blowout preventers of the equipment which
was used during the drilling of the well to support a string of
tubing and a valve which control the flow of fluids through the
string of tubing.
It will further be seen that the apparatus includes flow conductor
means which comprises inner and outer concentric flow conductors
which provide an annular passage for the flow of control fluid to
and from the valve and that the outer flow conductor above the
valve is held by a blowout preventer.
It will further be seen that the annular passage provided by the
concentric flow conductors may extend to the surface if desired, as
in the case of the installations illustrated in FIGS. 15 and 16, or
a small conduit 50, as in the case of the well installations
illustrated in FIGS. 1 and 14, may be provided to communicate with
the upper end of the annular passage.
It will further be seen that the flow conductors 49 and 50 may be
detachably secured by means of a connector head 31 connected to the
concentric flow conductors above the blowout preventers so that the
upper portions of the conductors which permit flow of fluids
through the string of tubing and permit movement of well tools
therethrough and of the control fluid may be easily disconnected
therefrom and reconnected thereto.
The foregoing description of the invention is explanatory only, and
changes in the details of the construction illustrated may be made
by those skilled in the art, within the scope of the appended
claims, without departing from the spirit of the invention.
* * * * *