U.S. patent application number 14/493626 was filed with the patent office on 2015-05-07 for annular blowout container (aboc).
The applicant listed for this patent is Dwight Baker. Invention is credited to Dwight Baker.
Application Number | 20150122482 14/493626 |
Document ID | / |
Family ID | 51522246 |
Filed Date | 2015-05-07 |
United States Patent
Application |
20150122482 |
Kind Code |
A1 |
Baker; Dwight |
May 7, 2015 |
Annular Blowout Container (ABOC)
Abstract
An annular blowout container (ABOC) that may be used in
multiples in a stack in conjunction with additional gate and shear
valves to protect a wellhead. The ABOC incorporates a cylindrical
formed bladder that provides a tight constrictive seal around
whatever pipe or tubing may be in the well bore. The bladder is
made of top and bottom rotator plates with springs extending
between the plates. The springs are encased in Teflon.RTM. and held
in place by Kevlar.RTM. then covered over completely with cured
Viton.RTM. that is injected to complete the overall bladder in a
molded form. Rotation of the top and bottom rotator plates effects
a twisting constriction around the drill pipe or tubing. Electrical
and hydraulic operational components are housed inside chambers
within the ABOC for predominantly self-contained operation. The
cylindrical bladder assembly may be removed and replaced after
extended use.
Inventors: |
Baker; Dwight; (Eagle Pass,
TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Baker; Dwight |
Eagle Pass |
TX |
US |
|
|
Family ID: |
51522246 |
Appl. No.: |
14/493626 |
Filed: |
September 23, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14183385 |
Feb 18, 2014 |
8844617 |
|
|
14493626 |
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|
61765895 |
Feb 18, 2013 |
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Current U.S.
Class: |
166/91.1 |
Current CPC
Class: |
E21B 33/085 20130101;
E21B 33/06 20130101 |
Class at
Publication: |
166/91.1 |
International
Class: |
E21B 33/06 20060101
E21B033/06 |
Claims
1. An annular blowout container (ABOC) for facilitating the
stoppage or restriction of the flow of fluids, solids, and gases
around a pipe or tubular structure within a borehole, the ABOC
comprising: a top section body having a central bore; a bottom
section body having a central bore and at least one component
chamber, the bottom section body removably attached to the top
section body; a flexible cylindrical bladder assembly, the bladder
assembly comprising: a flexible cylindrical bladder wall; a rotator
plate fixed to a first end of the flexible cylindrical bladder
wall; and a stationary plate fixed to a second end of the flexible
cylindrical bladder wall; and a rotator assembly for directing a
rotation of the rotator plate of the bladder assembly; wherein the
rotation of the rotator plate effects a twisting of the flexible
bladder wall and the constriction of the bladder wall around the
pipe or tubular structure within the central bore.
Description
CROSS REFERENCES TO RELATED APPLICATIONS
[0001] This application claims the benefit under 35 U.S.C.
.sctn.120 of co-pending U.S. patent application Ser. No.
14/183,385, filed Feb. 18, 2014; which further claims the benefit
under 35 U.S.C. .sctn.119(e) of U.S. Provisional Patent Application
Ser. No. 61/765,895, filed Feb. 18, 2013; the full disclosures of
which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates generally to valves, and more
particularly, but not by way of limitation, to a constriction valve
for controlling the flow of fluids from a well, especially during
uncontrolled well blowouts. The present invention more specifically
relates to devices for constricting around and closing off the
annular flow volume surrounding a pipe or tubing present in a well.
The present invention may therefore be described as an annular
blowout container (ABOC) and therefore relates to an improved
constriction valve for controlling the flow of drilling fluids and
hydrocarbon fluids and gases in a state of free flow known as
blowout in drilling and production phases, in combination with
additional valves that may be positioned at the well head.
[0004] 2. Description of the Related Art
[0005] The control and containment of free flowing fluids,
hydrocarbon fluids and gases in well drilling and production
operations is critical. There are a wide variety of blowout
preventers (BOPS) but these have a long history of failure. In
particular, various types of shear rams commonly used today are
hydraulically operated and are typically only designed to cut the
tube section of the drill pipe being used, not to stop the flow of
fluids. In addition, shear rams rely for proper placement and
function on the drill pipe being in a center position of the hole
to cut or sever the drill pipe tube only. Most blowouts, however,
occur during the tripping phase of drilling, and as a result, other
drilling tools such as drill collars and/or downhole tools are
frequently within the section to be closed.
[0006] A further significant cause of failure of blowout preventers
used today results from the fact that typically only the body of
the BOP is tested at API recommended pressures. The internal
components of BOPs used today rely on elastomeric components
installed in grooves to make contact with the body of the valve.
These elastomeric components will generally not contain higher
pressures above 5,000 psi. Therefore, the BOPs in use today are
significantly overrated for use in conjunction with higher
pressures.
SUMMARY OF THE INVENTION
[0007] The present invention provides an annular blowout container
(ABOC) that may be used in conjunction with one or more additional
standard blowout containers (BOCs). The ABOC of the present
invention incorporates a bladder of approximately 7-10 feet in
height that provides approximately 3.5-4.5 feet of tight
constrictive seal around whatever pipe or tubing may be in the well
bore. The bladder is made of top and bottom rotator plates with
springs extending between the plates. The springs are encased in
Teflon.RTM. and held in place by Kevlar.RTM. then covered over
completely while in a form with liquid Viton.RTM. that is injected
to complete the overall bladder in a molded form.
[0008] These molded bladders may be removed and replaced in the
ABOC by removing the top section of the valve housing and twisting
out the bladder assembly. Inside the ABOC body are two cavities,
one for holding hydraulic oil and the electrically driven hydraulic
pump needed for power to activate the rotators, and the second is
utilized for holding the batteries in the self contained
system.
[0009] The top and bottom rotator plates are moved in a
counter-revolutionary manner as they are affixed to the bladder so
as to twist and constrict the bladder to a full grip and sure seal
against the pipe or tubing that is in the drill string. The
flexible form of the bladder allows it to constrict around
irregular components such as collars on the drill string without
sacrificing the tightness of seal. The rotators turn the bladder
approximately one-quarter of a turn or slightly more to collapse
the bladder to the outside diameter of the object in the drill
string. This quick rotator action therefore provides the time
necessary to get the blowout stopped or stalled out so that heavy
mud can be pumped down the hole to stop the pressure at its source.
The present ram type BOPs are generally antiquated in that they
rely on seals to hold back rated pressures of the fluid flow when
in fact the rubber type seals are only rated for up to 5,000 psi
and the BOP bodies are open to returning gases, fluids, and solids
coming from the drilled hole. These existing BOPs are generally
overly complex and rely on the rig as a source for hydraulic oil
pressure to activate.
[0010] The internal bladder in the ABOC of the present invention
contains rows of springs that are arranged and placed in between
the two steel upper and lower rotator plates. The plates are
preferably circular with an internal aperture that is required for
the ABOC to be fully open for drilling and/or production purposes.
The arrangement of the holes drilled in the plates for installation
of the springs are preferably in a circular pattern with the holes
being drilled progressing towards the center in a circular pattern
toward an inside diameter. A preferred embodiment has four
concentric rings of apertures forming attachment points for the
springs suspended between the rotating plates. The springs are
preferably made in the manner of rebar with external ridges for
internal holding power. The springs are preferably constructed from
prime steel suitable for spring making For severe service the
springs may be made using suitable alloys that will withstand
hydrogen sulfide and carbon dioxide gases, as well as other severe
service environments. After the springs are cut to length and heat
treated, they are put through a coating process with a first
coating of a Teflon.RTM. based mixture applied. This first coating
is preferably a mixture of Teflon.RTM. and other materials that
allow the Teflon.RTM. to flex and stretch as needed in the
compression cycle of the valve. Over the Teflon.RTM. mixture
coating, a second layer of coating in the form of a Kevlar.RTM.
mixture is applied. The springs are then installed between the top
and bottom plates affixing each end to form the basic bladder. Once
the basic bladder has been completed in this manner, it is placed
in a mold with the outside diameter and the inside diameters set as
needed for the geometry of the valve. Pressurized Viton.RTM. is
then pumped in and allowed to cure, filling the spaces between the
coated springs and inside the mold containment.
[0011] The upper bladder plate section is attached to the top
rotator assembly inside the ABOC. Likewise, the lower section of
the bladder plate is attached to the bottom rotator assembly. The
function of the rotators is to turn the bottom and top plates in a
counter-revolutionary direction a quarter turn or more for each
action. When the rotator plates are thus turned, the bladder will
compress towards the center contacting and pressing against
whatever tube or pipe is in the hole opening. This compression
seals off the bottom from the top as a constrictive valve. The
molded in Viton.RTM. will compress, but is resistant to tear or
being shredded. Extreme high flowing gases, liquids and solids can
be stalled out (slowed down) for a significant time using the ABOC
bladder while other drilling blowout measures are used to load the
hole with more drilling fluids that can then be pumped down the
drill pipe. The bottom rotator assembly is designed to allow the
plate to move up as the twisting action on the bladder is applied.
As the height of the bladder is shortened on twisting compression,
one portion of the assembly (the top or bottom rotator plate) must
be allowed to move towards the center of the assembly.
[0012] The hydraulic oil contained on the back side of the bladder
is compressed further as piston mechanisms move up into the
hydraulic fluid. In the same manner, the high pressure gases and
fluids enter into a piston assembly under the bottom rotator plate
that will additionally compress the hydraulic fluid, thus
increasing the pressure on the back side of the bladder sealing
element, and further facilitating the force with which the bladder
constricts against the tube or pipe.
[0013] The height of the springs before attaching all of the
hardware in the construction of the bladder is preferably about
7-10 feet. Tests show that approximately one-third of the spring
section will provide a seal tight grip around the tube or pipe
within the center of the bladder assembly. The rotator plates are
preferably driven by a number of worm gear drive assemblies through
either a direct linkage to the edge of the plate (formed with gear
teeth) or through a gear coupling connecting to the hydraulic fluid
pumps.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a partial cross-sectional view of the annular
blowout container (ABOC) device of the present invention shown with
a section of pipe or tubing positioned through the center bore of
the assembly.
[0015] FIG. 2 is a partial cross-sectional view through the middle
of the annular blowout container assembly showing one of the two
rotator plates in conjunction with the surrounding valve body, as
well as one of the two rotating drive mechanisms.
[0016] FIG. 3 is a detailed cross-sectional view of one edge of the
lower rotator plate of the bladder assembly of the present
invention showing the manner in which pressurized fluids may flow
behind (to the outside of) the bladder wall to facilitate its
compression against the interior pipe or tubing.
[0017] FIG. 4 is a detailed cross-sectional view of a portion of
the spring assembly making up a part of the structure of the
bladder assembly and the various layers associated with each
individual spring and the overall assembly.
[0018] FIG. 5 is a detailed side plan view of one manner of
translating the rotational worm gear drive to one of the rotator
plates of the bladder assembly designed to move laterally (upwards)
on constriction.
[0019] FIG. 6A is an elevational view of the bladder assembly of
the present invention shown in an unconstricted configuration.
[0020] FIG. 6B is a cross-sectional view of the unconstricted
bladder assembly of the present invention shown in FIG. 6A.
[0021] FIG. 7A is an elevational view of the bladder assembly of
the present invention shown with rotator plates counter-rotated and
with the assembly in an overall constricted configuration.
[0022] FIG. 7B is a cross-sectional view of the constricted bladder
assembly of the present invention shown in FIG. 7A.
[0023] FIG. 8 is a cross-sectional view of a wellhead assembly
comprising three of the ABOCs of the present invention in
conjunction with a variety of other BOC valves and components.
[0024] FIG. 9 is a cross-sectional view of a wellhead assembly
comprising two of the ABOCs of the present invention linked
together with a hydraulic back pressure system useful in
conjunction with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0025] Reference is made first to FIG. 1 for a detailed description
of the internal structures of the ABOC device of the present
invention. Annular blowout container 10 shown in cross-section in
FIG. 1 is constructed primarily of top section body 12 and bottom
section body 14. Top connector flange 16 connects the ABOC to the
upper wellhead assembly (the balance of the components) and bottom
connector flange 19 attaches the ABOC to the lower wellhead
assembly 20. Various secure means for connecting top section body
12 to bottom section body 14, such as the use of a radial array of
tapered bolts, may be implemented.
[0026] A section of drill pipe 22 is shown positioned within the
ABOC central bore, although it will be recognized that the tubular
component within the bore may be drill pipe or production tubing.
Positioned within top section body 12 is top drive assembly 24
which incorporates top drive motor 26. This drive assembly serves
to rotate the top rotator disc 34 as described in more detail
below. Associated with bottom section body 14 is bottom drive
assembly 28 incorporating bottom drive motor 30. This assembly
serves to counter-rotate bottom rotator disc 36.
[0027] The counter-rotation of top rotator disc 34 and bottom
rotator disc 36 serves to twist and constrict bladder assembly 38
(shown in a relaxed condition in FIG. 1). When constricted, the
bladder assembly has a profile 40 (dashed line) whereby a seal is
created against drill pipe 22.
[0028] Also within bottom section body 14 are power supply and
instrument chamber 32a and hydraulic supply chamber 32b. Power
supply and instrument chamber 32a contains the necessary electrical
batteries to operate the hydraulic pumps that in turn operate top
drive motor 26 and bottom drive motor 30. Also within chamber 32a
are control electronics and instrumentation connected externally
(preferably through a hot stab connection) to the ABOC that allows
for both monitoring of the condition of the ABOC and its remote
control. In chamber 32b, both a hydraulic fluid reservoir and the
necessary electrically driven hydraulic pumps provide the high
pressure hydraulics required to operate the top drive assembly 24
and the bottom drive assembly 28. Each of the chambers shown may
comprise multiple chambers radially arrayed about the center bore
of bottom section body 14. The use of these chambers to hold and
house the various operational and control elements of the ABOC
eliminates much of the external connections (hydraulic and
electrical) that are normally required for such valves.
[0029] Additional detail highlighted by Detail Section A is
described in conjunction with FIG. 3 and is associated with the
operation of a back pressure hydraulic fluid system that
facilitates the maintenance of the seal of the bladder against the
drill pipe.
[0030] FIG. 2 shows a partial cross-sectional view looking down on
lower valve assembly 50 primarily structured within bottom section
body 14. In this view, drill pipe 22 is shown positioned in the
central bore surrounded by bladder assembly 38. Bladder assembly 38
is positioned integrally with rotator disc 36 (having a gear tooth
edge). An array of alignment back springs 42 are positioned around
bladder assembly 38 in a manner that allows the assembly to return
to an unconstricted configuration after activation. These alignment
back springs 42 are positioned on top set plate 44 in a manner
described in detail below with reference to FIG. 3.
[0031] Rotator disc 36 is turned (counter to the rotation of the
top rotator disc 34) by means of bottom drive assembly 28. Bottom
drive motor 30 turns worm gear drive shaft 52 set in position to
engage the gear tooth edge of rotator disc 36 and held in place by
drive bearing 54. Power supply and instrument chamber 32a and
hydraulic supply chamber 32b are shown from above in the view of
FIG. 2.
[0032] FIG. 3 shows the Detail Section A referenced in FIG. 1.
Bladder assembly 38 is shown mounted in conjunction with rotator
disc 36 that is itself positioned on top set plate 44 and bottom
set plate 46. Alignment back springs 42 are affixed to top set
plate 44 and again provide the necessary return force to
re-position and re-set the configuration of bladder assembly 38
after use. Intensifier pistons 48 provide a means for conducting
high pressure hydraulic fluids to the back side of bladder assembly
38 so as to augment the constrictive force associated with the
twisting of the bladder around drill pipe 22. All of these
components are configured within bottom section body 14 and are
mirrored in other radial directions about the center bore of the
assembly. The upper and lower plates that hold the integrated parts
of the bladder together will preferably have O-ring grooves cut to
width and depth to hold large diameter and high pressure Viton.RTM.
O-rings. This would insure a tight seal during installation of the
bladder. Such O-ring use, even in very high pressure environments
has been proven in the industry.
[0033] FIG. 4 displays in greater detail the internal construction
of bladder assembly 38. In the expanded detail shown in FIG. 4,
each individual steel spring 62 is shown to comprise Teflon.RTM.
layer 64 surrounded by Kevlar.RTM. layer 66. The entire array of
springs 62 is then assembled on rotator disc 36 (and rotator disc
34, shown in FIG. 1) in an array of four concentric circles in the
preferred embodiment and positioned within a mold. Liquid
Viton.RTM. is injected to fill the spaces between the springs to
form Viton.RTM. layer 68. This produces flexible bladder wall 60
which, when constricted, seals against the drill pipe or
tubing.
[0034] FIG. 5 shows in greater detail one manner of allowing for
the movement of rotator disc 36 laterally (upward) when bladder
assembly 38 is constricted. As worm gear drive shaft 52 turns, it
causes the rotation of vertical slide gear 72 which in turn rotates
rotator disc 36 through its gear tooth edge. Because of the greater
width (height) of vertical slide gear 72, rotator disc 36 may move
upward upon the constriction of bladder assembly 38 while still
maintaining contact with the gear teeth of slide gear 72. This
eliminates the necessity of adapting worm gear drive shaft 52 to
accommodate the lateral movement of rotator disc 36.
[0035] FIGS. 6A & 6B as well as FIGS. 7A & 7B show the
functionality of the bladder assembly of the present invention.
FIG. 6A shows an external view of the unconstricted bladder
assembly 38 having top rotator disc 34 and bottom rotator disc 36
all of which surround drill pipe 22. FIG. 6B shows these same
components internally (in cross-section) and demonstrates the
manner in which the annular space around drill pipe 22 permits the
flow of fluids (in either direction) through the open bladder
assembly and therefore through the ABOC. FIG. 7A shows an external
view of bladder assembly 38 after the counter-rotation of top
rotator disc 34 and bottom rotator disc 36. It is also noted that
bottom rotator disc 36 moves upward during the constriction
process. This counter-rotation around drill pipe 22 causes the
mid-section of bladder assembly 38 to decrease in both its inside
diameter and its outside diameter. The constriction of the inside
diameter, of course, provides the necessary seal against drill pipe
22 as shown in FIG. 7B. The degree to which this seal applies force
against drill pipe 22 is in part a function of the degree to which
rotator discs 34 & 36 have been counter-rotated. One quarter
(90.degree.) turn of each disc will effectively provide a seal that
extends over approximately one-third of the overall height of
bladder assembly 38.
[0036] Repeated use of the same bladder is anticipated both in
testing and in actual operations. Despite the capacity to be
repeatedly operated, the components of the ABOC that are subject to
degradation over time are still primarily confined to the
replaceable bladder. In this manner, the ABOC of the present
invention may, after an extended period of use, be easily re-built
by replacing the bladder assembly and the soft seal components. The
hard steel components of the device will need little in the way of
replacement or maintenance.
[0037] FIG. 8 discloses wellhead superstructure 80 made up of an
array of valves, BOCs and ABOCs in a configuration associated with
well head 86. The components in superstructure 80 are supported by
superstructure support frame 17 shown in dashed outline form for
clarity. The assembly shown in FIG. 8 includes three ABOCs
comprising first ABOC 10a positioned on top of second ABOC 10b,
which is positioned on top of third ABOC 10c. This array of ABOCs
is positioned on top of blowout container (BOC) 82 as may be one of
a number of typical such BOCs in the field. One gate valve 84 may
be positioned between the BOC assembly and wellhead 86. Shear spool
88 forms a primary component of BOC 82. All of this assembly
surrounds drill pipe 22 as shown. A second gate valve 90 is
positioned in what is referred to as the "dead man position" at the
top of the wellhead superstructure 80. Other arrangements and
numbers of ABOCs and BOCs are anticipated.
[0038] Reference is finally made to FIG. 9 which provides one
example of a system for facilitating the placement of back pressure
against the outside wall of the bladder assembly of the ABOC of the
present invention. FIG. 9 shows a first ABOC 10a and a second ABOC
10b stacked as referenced in part in FIG. 8. Back pressure assembly
100 is generally constructed with flanged outlet 102 into a lower
spool of the wellhead superstructure 80 assembly. This conducts the
pressure of the drilling or production fluids to hydraulic valve
104 and through right angle fixture 106 to overpressure transfer
piston 108. Right angle fixture 106 is preferably a forged studded
connection structured to withstand the rush of high pressure
fluids, gases, and solids resulting from the opening the gate valve
within the wellhead system. The transfer piston 108 communicates
the high pressure of the bore hole fluids to the hydraulic fluid
system associated with the ABOCs. Through bladder backside port
110, the hydraulic fluid system connects by way of T fixture 112 to
overpressure transfer piston 108 and additionally upward through
high pressure hydraulic line 114 through L-fixture 116 to a
corresponding bladder backside port 118 on the first ABOC 10a. In
this manner, the high pressures of the drilling fluids or
production fluids that may be experienced within the bore hole
during a blowout condition may be transferred to the hydraulic
fluids of the ABOCs to provide higher pressure hydraulic fluid that
facilitates a back pressure against the bladder assemblies as
described above to further strengthen the seal of the bladder
against the drill pipe.
[0039] Although the present invention has been described in
conjunction with certain preferred embodiments, it is anticipated
that variations in both the size and geometry of the structures may
be utilized without departing form the spirit and scope of the
invention. To some extent, the geometry of the various components
described (the height of the bladder assembly, for example) is
determined by the drilling and bore hole environment within which
the ABOC is intended to operate. Higher pressure environments may
require larger bladder assemblies, whereas lower pressure
terrestrial environments may require smaller bladder assemblies.
Once again, such variations that are primarily determined by the
levels of pressure associated with the operating environment do not
necessarily depart from the spirit and scope of the claimed
invention.
* * * * *