U.S. patent application number 12/343530 was filed with the patent office on 2010-06-24 for continuous fluid circulation valve for well drilling.
Invention is credited to Britt O. Braddick.
Application Number | 20100155143 12/343530 |
Document ID | / |
Family ID | 41717352 |
Filed Date | 2010-06-24 |
United States Patent
Application |
20100155143 |
Kind Code |
A1 |
Braddick; Britt O. |
June 24, 2010 |
CONTINUOUS FLUID CIRCULATION VALVE FOR WELL DRILLING
Abstract
Fluid circulation valve (10) is provided for use with a well
drilling operation, so that a drill joint may be added to or
removed from the drill string while circulating fluid into the
well. Valve housing (16, 12) has a central flow path therein, a
housing side port (87), and upper and lower threaded connectors for
engagement with the drill joint and the drill string, respectively.
A rotatable ball (24) is positioned within the flow path in the
valve housing and a ball side port (15) in fluid communication with
the housing side port (87) when the ball is closed. A tool (80) is
provided for engaging the valve housing and sealing between an
interior of the valve housing and the radially external flow line,
which passes fluid into the well when a drill joint is being
connecting to the upper end of the valve.
Inventors: |
Braddick; Britt O.;
(Houston, TX) |
Correspondence
Address: |
LOREN G. HELMREICH
5851 San Felipe, SUITE 975
HOUSTON
TX
77057
US
|
Family ID: |
41717352 |
Appl. No.: |
12/343530 |
Filed: |
December 24, 2008 |
Current U.S.
Class: |
175/218 ;
166/330 |
Current CPC
Class: |
E21B 21/00 20130101;
E21B 19/16 20130101 |
Class at
Publication: |
175/218 ;
166/330 |
International
Class: |
E21B 34/00 20060101
E21B034/00; E21B 7/00 20060101 E21B007/00 |
Claims
1. A fluid circulation valve for use in well drilling with a drill
joint and a drill string extending into the well, comprising: a
valve housing having a central flow path therein, an upper threaded
connector for threaded engagement with a lower end of a drill
joint, a lower threaded connector for threaded engagement with the
upper end of a drill string, and a housing side port for fluid
communication a flow line radially exterior of the valve housing; a
ball rotatably positioned within the flow path and having a
throughbore, the ball throughbore being in fluid communication with
the housing central flow path when the ball is open, and the ball
including a ball side port in fluid communication with the housing
side port when the ball is closed; an upper valve seat for sealing
between the ball and the housing; and a lower valve seat for
sealing between the ball and the housing.
2. A fluid circulation valve as defined in claim 1, wherein a
biasing member biases the upper valve seat toward the ball.
3. A circulation valve as defined in claim 1, further comprising: a
tool removably engagable with the valve housing to seal between an
interior of the valve housing and the flow line radially exterior
of the valve housing.
4. A circulation valve as defined in claim 3, wherein the tool
engages the housing side port for sealing with the exterior flow
line.
5. A circulation valve as defined in claim 1, further comprising: a
rotatable operating stem positioned within the valve body for
engaging the ball and rotating the ball to move between open and
closed positions.
6. A circulation valve as defined in claim 7, wherein the operating
stem comprises a pair of circumferentially opposing operating
stems.
7. A circulation valve as defined in claim 1, wherein a minimum
cross sectional flow area of the valve housing central flow path is
substantially the minimum cross section flow area of the ball
throughbore.
8. A circulation valve as defined in claim 1, wherein the valve
housing comprises an upper valve body and an interconnected lower
valve body.
9. A circulation valve as defined in claim 1, further comprising: a
ball rotator spaced axially from the ball, the ball rotator
rotatable with respect to the housing to rotate the ball between
open and closed positions.
10. A fluid circulation valve for use in well drilling with a drill
joint and a drill string extending into the well, comprising: a
valve housing having a central flow path therein, an upper threaded
connector for threaded engagement with a lower end of a drill
joint, a lower threaded connector for threaded engagement with the
upper end of a drill string, and a housing side port for fluid
communication a flow line radially exterior of the valve housing; a
ball rotatably positioned within the flow path and having a
throughbore, the ball throughbore being in fluid communication with
the housing central flow path when the ball is open, and the ball
including a ball side port in fluid communication with the housing
side port when the ball is closed; and a tool removably engagable
with the valve housing to seal between an interior of the valve
housing and a flow line radially exterior of the valve housing.
11. A circulation valve as defined in claim 10, further comprising:
an upper valve seat for sealing between the ball and the
housing.
12. A fluid circulation valve as defined in claim 11, further
comprising: a biasing member biases the upper valve seat toward the
ball.
13. A circulation valve as defined in claim 10, wherein the tool
engages the housing side port for sealing with the exterior flow
line.
14. A circulation valve as defined in claim 10, wherein a minimum
cross sectional flow area of the valve housing central flow path is
substantially the minimum cross section flow area of the ball
throughbore.
15. A circulation valve as defined in claim 10, wherein the valve
housing comprises an upper valve body and an interconnected lower
valve body.
16. A circulation valve as defined in claim 10, further comprising:
an operating stem positioned within the valve body for engaging the
ball and rotating the ball to move between open and closed
positions.
17. A fluid circulation valve for use in well drilling with a drill
joint and a drill string extending into the well, comprising: a
valve housing having a central flow path therein, an upper threaded
connector for threaded engagement with a lower end of a drill
joint, a lower threaded connector for threaded engagement with the
upper end of a drill string, and a housing side port for fluid
communication a flow line radially exterior of the valve housing; a
ball rotatably positioned within the flow path and having a
throughbore, the ball throughbore being in fluid communication with
the housing central flow path when the ball is open, and the ball
including a ball side port in fluid communication with the housing
side port when the ball is closed; an operating stem positioned
within the valve housing for engaging the ball and rotating the
ball between open and closed positions; and a tool removably
engagable with the valve housing to seal between an interior of the
valve housing and a line radially exterior of the valve
housing.
18. A fluid circulation valve as defined in claim 17, further
composing: an upper valve seat for sealing between the ball and the
housing; and a biasing member biases the upper valve seat toward
the ball.
19. A circulation valve as defined in claim 17, wherein the guide
block comprises a pair of circumferentially opposing guide
blocks.
20. A circulation valve as defined in claim 17, further comprising:
a ball rotator spaced axially from the ball, the ball rotator
rotatable with respect to the housing to rotate the ball between
open and closed positions.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a method and equipment for
drilling a well. More particularly, a circulation valve is provided
for interconnection with a drill string joint, such that during
conventional drilling the fluids pass through the drill string
joint, the valve, and the drill string in the well. When the drill
string connection is made up or broken apart, fluid is diverted
through a side port in the valve, thereby maintaining substantially
continuous fluid circulation.
BACKGROUND OF THE INVENTION
[0002] When drilling a hydrocarbon recovery well, the drill string
is conventionally rotated to drive the drill bit. When a mud motor
is used along the drill string to rotate the bit, the drill string
is frequently rotated at a speed less than the bit to keep solids
desirably suspended in the well fluids. Drilling mud is thus
circulated through the drill string and to the bit, and up the
annulus between the drill string and the wellbore. As one or more
joints are added to the string, the drilling process is briefly
stopped to make up the threaded interconnection of the joint to the
drill string. Although the drill string is normally full of fluid,
the pressure supplied by the mud pumps is lost when the pumps are
shut off as the threaded connection is made up. Restarting
circulation can be difficult, and may lead to numerous drilling
problems.
[0003] The prior art includes methods designed to allow a drill
joint to be added to or removed from a drill string while
circulation of mud continues. This prior art process utilizes a
coupler for substantially surrounding the threaded connection.
Various rams, preventers, slips, and other closing devices
substantially seal fluid within the coupler as the connection is
made up. Devices of this type are disclosed in U.S. Pat. Nos.
6,119,772, 6,591,916, 6,739,397, 7,028,586, and 7,252,151.
Publication WO98/16716 also discloses a continuous circulation
drilling method.
[0004] There are significant disadvantages to the above approach.
First, the mechanism for accomplishing continuous circulation
involves an expensive coupler, and numerous sealing devices are
provided to minimize leakage of mud from the encircling coupler.
The device is also expensive, and at least in some applications
slows down the makeup or breakout process, thereby contributing to
higher drilling costs. U.S. Pat. No. 4,478,244 discloses a mud
saver valve which may be threaded to a drill string to reduce mud
spills. U.S. application Ser. No. 11/786,495 discloses a safety
valve with a ball rotatable engaging an actuator sleeve.
[0005] The disadvantages of the prior art are overcome by the
present invention, in an improved technique for continuously
circulating drilling mud in a drill string is hereinafter
disclosed.
SUMMARY OF THE INVENTION
[0006] In one embodiment, a fluid circulation valve is provided for
use with a well drilling operation, wherein a drill joint may be
added to or removed from a drill string which extends into a well.
The fluid circulation valve includes a valve housing having a
central flow path therein, a housing side port, an upper threaded
connector for threaded engagement with the lower end of the drill
joint, and a lower threaded connector for threaded engagement with
an upper end of the drill string. A rotatable ball is positioned
within the flow path in the valve housing has a throughbore. The
ball throughbore is in fluid communication with the housing central
flow path when the ball is open, and a ball side port is in fluid
communication with the housing side port when the ball is closed.
The valve housing side port is in fluid communication with a line
radially exterior of the valve housing, and typically extending to
a mud pump. The fluid circulation valve includes an upper valve
seat for sealing between the ball and the housing, and a lower
valve seat for sealing between the ball and the housing. Fluid may
be continuously circulated through the drill string even when
adding or deleting a drill joint, since fluid may flow either
through the ball throughbore or though the ball side port. The
valve remains connected to the drill string as joints are added and
the string is run in the well. The housing side port is closed when
the ball throughbore is in fluid communication with the valve
housing central flow path. The upper side of valve throughbore is
closed when the ball is positioned to open the side port into the
interior of the housing.
[0007] These and further features and advantages of the present
invention will become apparent from the following detailed
description, wherein reference is made to the figures in the
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a cross-sectional view of one embodiment of a
fluid circulation valve.
[0009] FIG. 2 is a cross-sectional view through the valve shown in
FIG. 1.
[0010] FIG. 3 is a top view illustrating a suitable tool for
sealing between the valve body and a radially external flow
line.
[0011] FIG. 4 is a cross-sectional view of another embodiment of a
fluid circulation valve, with two circumferentially opposing
operating stems for rotatably guiding rotation of the ball.
[0012] FIG. 5 is a cross-sectional view of yet another embodiment
of a fluid circulation valve.
[0013] FIG. 6 illustrates the fluid circulation valve shown in FIG.
5 in another ball position.
[0014] FIG. 7 illustrates a tool for sealing between the valve body
and a radially external flow line.
[0015] FIG. 8 is a cross-sectional view of yet another embodiment
of a fluid circulation valve, wherein the ball actuator is axially
spaced from the ball.
[0016] FIG. 9 illustrates the fluid circulation valve in FIG. 8 in
the closed position.
[0017] FIG. 10 illustrates a tool for sealing between the valve
body and a radially external flow line.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0018] FIG. 1 illustrates one embodiment of a fluid circulation
valve according to the present invention. Circulation valve 10
includes a valve body, which as shown consists of an upper valve
body 16 having upper threads 18 for threaded interconnection with
the lower end of a pipe joint, and a lower valve body 12 having
lower threads 14 for threaded connection with an upper end of a
tubular string which extends into a wall. The bodies 12 and 16 are
joined by threads 20, with shoulder 22 acting between the bodies 12
and 16 to obtain a rigid connection, and to pass torque from above
the valve to below the valve while positioned along a drill string,
thereby allowing torque to be transferred to the bit to rotate the
bit, or to actuate components along the drill string. A seal 30 may
be provided for sealing between the housings 12 and 16. Those
skilled in the art will appreciate that fluid may be pumped through
the valve from the upper end of a pipe joint to the lower end of
the pipe joint, then through the bodies 16 and 12, then through a
tubular pipe string which extends into a well.
[0019] FIG. 1 illustrates a ball 24 rotatably positioned within the
valve housing, with the ball having a throughbore 41 defined by
side walls 42, such that the throughbore 41 is in fluid
communication with the bore 17 in the housing when the ball is in
the open position, as shown in FIG. 1. Mud or other drilling fluid
may thus be pumped from above the fluid circulation valve, through
the fluid circulation valve, and into the drill string when the
valve 10 is open.
[0020] The circulation valve preferably includes an upper valve
seat 28 which has a seal 32 for sealing engagement with the housing
12, and another seal 32 for sealing engagement with the ball 24.
The assembly further includes a lower ball seat 26 similarly having
a seal 32 for sealing engagement with the housing 16, and another
seal 32 for sealing with the ball 24. One or more biasing members,
such as a wave spring or a Beliville spring 27, may be included to
bias upper seat 28 axially downward for sealing engagement with the
ball, or to bias the lower seat 26 upward into sealing engagement
with the ball. Each seat thus may include a Beliville spring or a
wave spring to exert a desired biasing force to press the seat into
engagement with the ball. FIG. 1 also illustrates an operating stem
or guide block 34 with seal 36 for sealing engagement with the
housing 16, a noncylindrical external access pocket 38 for
receiving a ball rotating tool, and a noncylindrical actuating tab
40 for fitting within a similarly shaped recess within the ball to
rotate the ball when the operating stem or guide block 34 is
rotated, as explained hereafter.
[0021] FIG. 2 is a horizontal cross sectional view through the
valve and the ball in FIG. 1, with the ball 24 in the open
position. The operating stem 34 is shown with a radially inward key
40 (see FIG. 1) for inserting into a key into a receiving pocket in
the ball 24, so that the ball rotates in response to rotation of
the operating stem 34. The flange 33 retains the operating stem in
position with respect to the valve housing, thereby monitoring the
ball centered in spite of high pressure acting on the operating
stem. FIG. 2 also discloses an inlet ring 44 which is threaded at
46 into engagement with the housing 16, and is configured for
fluidly receiving an external flow line, as disclosed
subsequently.
[0022] FIG. 3 shows a suitable tool 80 for engaging an outer
surface of the housing 16, and for temporarily sealing between the
interior of valve 10 and a flow line 82 radially external of the
valve, with line 82 typically extending to a mud pump 83. The
exemplary tool has an arcuate portion 81 which substantially
surrounds the valve body 16, with curved interior surface 84
engaging the exterior surface of valve body. The tool 80 includes a
latch-type locking lugs 50 and 54, locking handle 52, and at least
one hollow pin 86 which fits within a respective cavity or recess
in the ring 85 when the handle is locked. Hinge 83 allows the ring
shaped tool to be easily put on and removed from the valve. FIG. 3
also illustrates seal 87 for acting between the tool and the ring
85, which defines the cavity or recess for receiving the external
fluid. The ball 24 is shown in FIG. 3 in the closed position, i.e.,
fluid is blocked from flowing from above to below the valve,
although fluid can flow from exterior flow line 82 to the ball and
then downward into the drill string. Other types of tools may be
used for sealingly engaging the valve body and the external flow
line.
[0023] FIG. 4 is similar to the FIG. 2 embodiment, except that a
pair of circumferentially opposing guide blocks or operating stems
34, 35 are provided, each with a tool recess pocket 38. One or both
operating stems may thus be rotated to rotate the ball between open
and closed positions. In one embodiment, one stem may be connected
to the ball 24 for rotating the ball to the open position and the
opposing stem rotated to move the ball to the closed position, as
shown in FIG. 3. Two radially opposing operating stems allow fluid
pressure to act on both operating stems, so that the opposing
forces cancel and the ball remains centered in the valve body
without using the flange 33 shown in FIG. 3. Also, FIG. 4 depicts
spring biased pins 56, 58 for exerting a biasing force from the
housing to the ball, and similar spring biased pins 57, 59 for
exerting a biasing force from ring 44 to the ball.
[0024] Referring now to FIG. 5, this version of a continuous fluid
circulation valve 10 is depicted with a ball valve 24 shown in the
open position for transmitting fluid from above to below the ball
valve. By rotating the operating stem 34, the ball may thus be
rotated between the open and closed positions. FIG. 6 illustrates
another cross sectional view of the valve shown in FIG. 5, and
illustrates another ring 62 threadably positioned within the side
body access port in the valve body, and a flapper member 66
pivotably connected to the ring member 62 and closing off the side
port of the valve body when the valve is in the open position, as
shown in FIG. 6. FIG. 7 depicts in greater detail a suitable tool
80 as previously disclosed for fluidly connecting flow line 82 to
the interior of the valve. The tool 80 thus seals to the ring 62,
as previously discussed. With the ball rotated to the closed
position, fluid may be pumped into the valve body, and fluid
pressure will be sufficient to swing the flapper 66 to the open
position, as shown in FIG. 7, thereby allowing fluid to enter the
interior of the ball and pass downward through the valve and into
the drill string.
[0025] FIG. 8 depicts another version of a continuous circulation
valve 10 according to the present invention, with a ball 24 as
previously discussed. In this embodiment, the ball is rotated
between an open and closed position and by rotating sleeve 72,
which includes threads 74 for mating with sleeve 76 extending
axially from connector 78, which interconnects the sleeve 76 with
the ball. By rotating the sleeve 72, the sleeve 76 moves axially
relative to the housings 16, 12, thereby rotating the ball. A large
pipe wrench or other suitable tool may be used for gripping the
external surface of sleeve 72 to rotate the sleeve and thereby the
ball between open and closed positions. FIG. 10 illustrates a
suitable tool 80 for sealingly engaging external flow line 82 to
the interior of the ball when the valve is in the closed position.
As with the prior embodiments, the tool is sealed to threaded ring
85 for passing fluid from a line radially exterior of the ball
valve into the well when the flow line from above to below the ball
valve is blocked.
[0026] In other embodiments, one of the rotating sleeve 72 and the
ball rotating member may include one or more projections which each
fit within a corresponding helical slot in the other of the
rotating sleeve and the ball rotating member, so that rotation of
the sleeve moves the ball rotating member axially in the same
manner as the threads discussed above. Threads are preferred for
most applications since they provide a large surface area for
transmitting axial forces to the ball to open or close the
ball.
[0027] The term "ball" as used herein is intended in its broad
sense to refer to a rotatable closing member in a valve, with at
least a portion of the outer surface of the ball being similar in
configuration to a portion of a sphere. While the ball as disclosed
herein obviously need not be a sphere, the ball does rotate about a
ball center.
[0028] The fluid circulation valve as disclosed herein may be used
in well drilling operations wherein fluid passes through a drill
joint, through the valve, and into the drill string while the valve
is in the open position, and fluid passes from an external flow
line, downward through a lower end of the valve body, and into the
drill string when the valve is closed. During the valve closed
cycle, the drill joint may be fluidly connected with the top of the
valve, and once this connection is complete, the valve may be
opened so that the external flow line is blocked and fluid can be
pumped into the well through the drill joint, which is now part of
the drill string.
[0029] Although specific embodiments of the invention have been
described herein in some detail, this has been done solely for the
purposes of explaining the various aspects of the invention, and is
not intended to limit the scope of the invention as defined in the
claims which follow. Those skilled in the art will understand that
the embodiment shown and described is exemplary, and various other
substitutions, alterations and modifications, including but not
limited to those design alternatives specifically discussed herein,
may be made in the practice of the invention without departing from
its scope.
* * * * *