U.S. patent application number 15/103176 was filed with the patent office on 2016-10-20 for fire-resistant structures for wellhead outlets and methods of using same.
The applicant listed for this patent is LANCER SYSTEMS L.P.. Invention is credited to Robert D. Cook, Jr., George Frank Denardo, Jr., Jonathan Allen Hartman, Brian Dennis Moyer.
Application Number | 20160305218 15/103176 |
Document ID | / |
Family ID | 49885457 |
Filed Date | 2016-10-20 |
United States Patent
Application |
20160305218 |
Kind Code |
A1 |
Denardo, Jr.; George Frank ;
et al. |
October 20, 2016 |
FIRE-RESISTANT STRUCTURES FOR WELLHEAD OUTLETS AND METHODS OF USING
SAME
Abstract
The present application teaches fire-resistant structures and
methods for wellhead outlets, and methods of using same. In one
embodiment, the fire-resistant structure includes a plurality of
spacing assemblies (32a-f) that space a plurality of fire-resistant
panels (42, 44, 46, 48, 49, 50, 53, 55) away from the exterior
surface of a wellhead outlet (1), such that a space or volume is
created between the fire-resistant panels (42, 44, 46, 48, 49, 50,
53, 55) and the exterior surface of the wellhead outlet (1).
Inventors: |
Denardo, Jr.; George Frank;
(Allentown, PA) ; Moyer; Brian Dennis; (Allentown,
PA) ; Cook, Jr.; Robert D.; (Allentown, PA) ;
Hartman; Jonathan Allen; (Allentown, PA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
LANCER SYSTEMS L.P. |
Quakertown |
PA |
US |
|
|
Family ID: |
49885457 |
Appl. No.: |
15/103176 |
Filed: |
December 12, 2013 |
PCT Filed: |
December 12, 2013 |
PCT NO: |
PCT/US2013/074562 |
371 Date: |
June 9, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
E21B 33/068 20130101;
E21B 35/00 20130101 |
International
Class: |
E21B 35/00 20060101
E21B035/00; E21B 33/068 20060101 E21B033/068 |
Claims
1. A kit for retrofitting an existing wellhead outlet, the existing
wellhead outlet having at least one exterior surface, the kit
comprising: a plurality of independent, elongated spacing
assemblies including at least a first and a second elongated
spacing assembly, the first and the second elongated spacing
assembly each being attachable at a first end thereof to the at
least one exterior surface of the existing wellhead outlet, the
first and the second elongated spacing assembly being attachable at
a first and a second respective attachment position along the at
least one exterior surface, the first attachment position being
spaced apart laterally along the at least one exterior surface from
the second attachment position, the first and the second elongated
spacing assembly each further comprising an opposite second end
that is spaced apart along the respective assembly from the first
end; and at least one panel that is attachable to the second end of
each of the first and the second elongated spacing assembly, the at
least one panel being attachable to the first and the second
elongated spacing assembly at a first and a second respective
support position along the at least one panel, the first support
position being spaced apart laterally along the at least one panel
from the second support position; wherein the plurality of
independent, elongated spacing assemblies and the at least panel
are attachable with the at least one exterior surface to form an
enclosure for the existing wellhead outlet that is spaced apart to
be offset from the at least one exterior surface and is supported
by the plurality of laterally-spaced, independent, elongated
spacing assemblies.
2. The kit of claim 1, wherein the at least one panel includes at
least one frameless fire-resistant panel comprised of a unitary,
flame-retardant, high-strength material configured to be attached
directly to the second end of each of the first and the second
elongated spacing assembly without having a frame support
structure.
3. The kit of claim 1, wherein each of the plurality of
independent, elongated spacing assemblies is comprised of an
elongated spacing fastener and an insulated material.
4. The kit of claim 2, wherein the unitary, flame-retardant,
high-strength material for the at least one panel is selected from
the group consisting of a ceramic material and a fiber-reinforced
composite.
5. The kit of claim 1, wherein the at least one panel and the
plurality of independent, elongated spacing assemblies can fully
enclose the wellhead outlet, except for any port that extends from
the wellhead outlet.
6. The kit of claim 1, wherein each of the plurality of
independent, elongated spacing assemblies includes at least one
removable fastener that attaches the independent, elongated spacing
assembly to the wellhead outlet.
7. An apparatus comprising: a plurality of independent, elongated
spacing assemblies including at least a first and a second
elongated spacing assembly, the first and the second elongated
spacing assembly each being attachable at a first end thereof to at
least one exterior surface of an existing wellhead outlet, the
first and the second elongated spacing assembly being attachable at
a first and a second respective attachment position along the at
least one exterior surface, the first attachment position being
spaced apart laterally along the at least one exterior surface from
the second attachment position, the first and the second elongated
spacing assembly each further comprising a second end that is
spaced apart along the respective assembly from the first end; and
at least one frameless fire-resistant panel attached to the second
end of each of the first and second elongated spacing assembly, the
at least one frameless fire-resistant panel being attached to the
second end of the first and second elongated spacing assembly at a
first and a second respective support position along the at least
one frameless fire-resistant panel, the first support position
being spaced apart laterally along the at least one frameless
fire-resistant panel from the second support position; wherein the
plurality of independent, elongated spacing assemblies and the at
least one frameless fire-resistant panel are configured to be
attached with the at least one exterior surface of the wellhead
outlet such that a frameless fire-resistant enclosure is configured
to be formed for the existing wellhead outlet that is spaced apart
to be offset from the at least one exterior surface of the wellhead
outlet and is supported by the plurality of laterally spaced,
independent, elongated spacing assemblies.
8. The apparatus of claim 7, wherein the at least one frameless
fire-resistant panel is comprised of a unitary, flame-retardant,
high-strength material configured to be attached directly to the
second end of each of the first and the second elongated spacing
assembly without having a frame support structure.
9. The apparatus of claim 7, wherein each of the plurality of
independent, elongated spacing assemblies is comprised of an
elongated spacing fastener and an insulated material.
10. The apparatus of claim 9, wherein the elongated spacing
fastener is selected from the group consisting of a bolt, a portion
of a bolt, a lag, a screw, a rod, a pipe and a tube.
11. The apparatus of claim 7, wherein the at least one frameless
fire-resistant panel includes a plurality of frameless
fire-resistant panels that are configured to be spaced apart to be
offset from the at least one exterior surface of the existing
wellhead outlet and to be attached together to fully enclose the
wellhead outlet, except for any port that extends from the wellhead
outlet.
12. The apparatus of claim 7, wherein each of the first and second
elongated spacing assemblies includes a removable fastener, and the
at least one frameless fire-resistant panel is removably attached
to the second end of each of the first and second elongated spacing
assembly.
13. A method of protecting a wellhead outlet, the wellhead outlet
having at least one exterior surface, the method comprising:
attaching to the at least one exterior surface of the wellhead
outlet a plurality of independent, elongated spacing assemblies
that include at least a first and a second elongated spacing
assembly, each of the first and the second elongated spacing
assembly comprising a first end and a second end that is spaced
apart along the assembly from the first end, the step of attaching
including: attaching the first end of the first elongated spacing
assembly to the at least one exterior surface at a first attachment
position along the at least one exterior surface; and attaching the
first end of the second elongated spacing assembly to the at least
one exterior surface at a second attachment position along the at
least one exterior surface that is spaced apart laterally along the
at least one exterior surface from the first attachment position;
and attaching one or more panels to the plurality of independent,
elongated spacing assemblies such that the one or more panels are
spaced apart to be offset from the at least one exterior surface of
the wellhead outlet.
14. The method of claim 13, further comprising the step of tapping
a plurality of threaded holes into the at least one exterior
surface of the wellhead outlet including tapping at least a first
threaded hole into the at least one exterior surface at the first
attachment position and a second threaded hole into the at least
one exterior surface at the second attachment position, wherein the
step of attaching to the at least one exterior surface of the
wellhead outlet a plurality of independent, elongated spacing
assemblies one comprises attaching the first and the second
elongated spacing assembly to the first and the second threaded
hole respectively at the first and the second attachment
position.
15. The method of claim 13, wherein the step of attaching one or
more panels to the plurality of independent, elongated spacing
assemblies comprises attaching the one or more panels to the
plurality of independent, elongated spacing assemblies, wherein the
one or more panels comprise one or more frameless fire-resistant
panels.
16. The method of claim 13, wherein the step of attaching one or
more panels to the plurality of independent, elongated spacing
assemblies further comprises fully enclosing the wellhead outlet
within the one or more panels, except for any port that extends
from the wellhead outlet.
17. The method of claim 13, wherein the step of attaching one or
more panels to the plurality of independent, elongated spacing
assemblies further comprises including one or more holes in the one
or more panels to permit one or more ports that extends from the
wellhead outlet to extend through the one or more panels.
18. The method of claim 17, further comprising the step of filling
any gap between the one or more ports and a respective one of the
one or more holes located in the one or more panels with a
flame-retardant ceramic material.
19. (canceled)
20. The method of claim 13, wherein the step of attaching one or
more panels to the plurality of independent, elongated spacing
assemblies comprises attaching the one or more panels to the
plurality of independent, elongated spacing assemblies that are
removable from the one or more spacing assemblies.
21. The method of claim 13, further comprising: removing the one or
more panels from the one or more spacing assemblies; and
reattaching the one or more panels to the one or more spacing
assemblies.
22-28. (canceled)
Description
FIELD OF THE INVENTION
[0001] The present invention relates to fire-resistant structures
and methods of using same, and more particularly to fire-resistant
structures and methods for wellhead outlets and methods of using
same.
BACKGROUND OF THE INVENTION
[0002] A wellhead is a component used at the surface of an oil or
gas well that provides structural and pressure-containing interface
for the drilling and production equipment. Wellheads are often
welded to the first string of casing, which has been cemented in
place over the well. Thus, wellheads often form an integral part of
a well once initially installed.
[0003] Because oil and gas are highly flammable and because the
environments in which oil and gas wells are located are often
dangerous, it is desirable to provide adequate safety measures to
protect wellheads and surrounding structures from
potentially-damaging fires. Accordingly, there is a need for
fire-resistant structures for wellhead outlets and methods of using
same.
ASPECTS OF THE INVENTION
[0004] Additional aspects of the invention include:
[0005] Aspect 1: A kit for retrofitting an existing wellhead
outlet, the existing wellhead outlet having at least one exterior
surface, the kit comprising at least one spacing assembly, the at
least one spacing assembly being attachable at a first end thereof
to the at least one exterior surface of the existing wellhead
outlet, the at least one spacing assembly further comprising a
second end that is spaced apart from the first end; and at least
one panel that is attachable to the second end of the at least one
spacing assembly.
[0006] Aspect 2: The kit according to Aspect 1, wherein the at
least one panel is comprised of a flame-retardant ceramic
material.
[0007] Aspect 3: The kit according to either of Aspect 1 or Aspect
2, wherein the at least one spacing assembly is comprised of an
insulated material.
[0008] Aspect 4: The kit according to any of Aspects 1-3, wherein
each of the at least one panel has a planar exterior surface.
[0009] Aspect 5: The kit according to any of Aspects 1-4, wherein
the at least one panel and at least one spacing assembly can fully
enclose the wellhead outlet, except for any port that extends from
the wellhead outlet.
[0010] Aspect 6: The kit according to any of Aspects 1-5, wherein
the at least one spacing assembly includes at least one removable
fastener that attaches the at least one spacing assembly to the
wellhead outlet.
[0011] Aspect 7: An apparatus comprising: a wellhead outlet having
at least one exterior surface; and at least one panel attached to
the at least one exterior surface of the wellhead outlet such that
the at least one panel is spaced apart from the at least one
exterior surface of the wellhead outlet.
[0012] Aspect 8: The apparatus according to Aspect 7, wherein the
at least one panel is comprised of a flame-retardant ceramic
material.
[0013] Aspect 9: The apparatus according to either of Aspect 7 or
Aspect 8, further comprising at least one spacing assembly attached
to both the at least one panel and the at least one exterior
surface of the wellhead outlet and acts to space the at least one
panel apart from the at least one exterior surface of the wellhead
outlet.
[0014] Aspect 10: The apparatus according to Aspect 9, wherein the
at least one spacing assembly is comprised of an insulated
material.
[0015] Aspect 11: The apparatus according to any of Aspects 7-10,
wherein the at least one panel can fully enclose the wellhead
outlet, except for any port that extends from the wellhead
outlet.
[0016] Aspect 12: The apparatus according to any of Aspects 7-11,
wherein the at least one panel is attached to the at least one
exterior surface of the wellhead outlet using at least one
removable fastener.
[0017] Aspect 13: A method of protecting a wellhead outlet, the
wellhead outlet having at least one exterior surface, the method
comprising: attaching one or more spacing assemblies to the at
least one exterior surface of the wellhead outlet; and attaching
one or more panels to the one or more spacing assemblies such that
the one or more panels are spaced apart from the at least one
exterior surface of the wellhead outlet.
[0018] Aspect 14: The method according to Aspect 13, further
comprising the step of tapping a threaded hole into the at least
one exterior surface of the wellhead outlet, wherein the step of
attaching one or more spacing assemblies to the at least one
exterior surface of the wellhead outlet comprises attaching one or
more spacing assemblies to the threaded hole.
[0019] Aspect 15: The method according to either of Aspect 13 or
Aspect 14, wherein the step of attaching one or more panels to the
one or more spacing assemblies comprises attaching one or more
panels to the one or more spacing assemblies, wherein the one or
more panels is comprised of a flame-retardant ceramic material.
[0020] Aspect 16: The method according to any of Aspects 13-15,
wherein the step of attaching one or more panels to the one or more
spacing assemblies further comprises fully enclosing the wellhead
outlet within the one or more panels, except for any port that
extends from the wellhead outlet.
[0021] Aspect 17: The method according to any of Aspects 13-16,
wherein the step of attaching one or more panels to the one or more
spacing assemblies further comprises including one or more holes in
the one or more panels to permit one or more ports that extends
from the wellhead outlet to extend through the one or more
panels.
[0022] Aspect 18: The method according to Aspect 17, further
comprising the step of filling any gap between the one or more
ports and a respective one of the one or more holes located in the
one or more panels with a flame-retardant ceramic material.
[0023] Aspect 19: The method according to Aspect 18, wherein the
step of filling any gap further comprises filling any gap with a
thermal blanket.
[0024] Aspect 20: The method according to any of Aspects 13-19,
wherein the step of attaching one or more panels to the one or more
spacing assemblies comprises attaching one or more panels to the
one or more spacing assemblies that are removable from the one or
more spacing assemblies.
[0025] Aspect 21: The method according to any of Aspects 13-20,
further comprising: removing the one or more panels from the one or
more spacing assemblies; and reattaching the one or more panels to
the one or more spacing assemblies.
[0026] Aspect 22: A method of protecting a wellhead outlet having
at least one gasket, the at least one gasket having a
circumference, the wellhead outlet having at least one exterior
surface, the method comprising: attaching at least one panel to the
at least one exterior surface of the wellhead outlet to form an
enclosure around the wellhead outlet, wherein the enclosure
provides sufficient insulation for the wellhead outlet in order to
prevent the at least one gasket from leaking at a rate in excess of
1 ml/in. per minute of mean measurement of the circumference of the
at least one gasket when the wellhead outlet has been pressurized
to at least 75% of its rated working pressure with water after the
enclosure has been exposed to a continuous flame of at least 1000
degrees F. (538 degrees C.) for at least 30 minutes.
[0027] Aspect 23: The method according to Aspect 22, wherein the
step of attaching at least one panel to the at least one exterior
surface of the wellhead outlet to form an enclosure around at least
a portion of the wellhead outlet further comprises attaching one or
more spacing assemblies to the at least one exterior surface of the
wellhead outlet and attaching the at least one panel to the one or
more spacing assemblies.
[0028] Aspect 24: The method according to either of Aspect 22 or
Aspect 23, wherein the step of attaching at least one panel to the
at least one exterior surface of the wellhead outlet further
comprises attaching least one panel to the at least one exterior
surface of the wellhead outlet having at least one non-planar
surface.
[0029] Aspect 25: A system comprising: a wellhead outlet having at
least one exterior surface; and at least one flame-retardant panel
that is directly attached to the at least one exterior surface of
the wellhead outlet.
[0030] Aspect 26: The system according to Aspect 25, wherein the at
least one flame-retardant panel is in contact with the at least one
exterior surface of the wellhead outlet.
[0031] Aspect 27: The system according to either of Aspect 25 or
Aspect 26, wherein the at least one flame-retardant panel is
removably attached to the at least one exterior surface of the
wellhead outlet.
[0032] Aspect 28: The system according to any of Aspects 25-27,
wherein the at least one flame-retardant panel has at least one
non-planar surface.
BRIEF DESCRIPTION OF THE DRAWINGS
[0033] The foregoing summary, as well as the following detailed
description of the invention, will be better understood when read
in conjunction with the appended drawings. For the purpose of
illustrating the invention disclosed herein, certain embodiments in
accordance with the herein disclosed invention are shown in the
drawings. It should be understood, however, that the herein
disclosed invention is not limited to the precise arrangements
shown. It should also be understood that, in the drawings, the
parts are not necessarily drawn to scale. The present invention
will hereinafter be described in conjunction with the appended
drawing figures, wherein like numerals denote like elements. In the
drawings:
[0034] FIG. 1 is a top perspective view of an exemplary wellhead
outlet according to the prior art;
[0035] FIGS. 2A and 2B are perspective views of an exemplary
wellhead outlet according to the prior art, partially outfitted
with a fire-resistant enclosure according to the present
invention;
[0036] FIGS. 3A and 3B are perspective views of an exemplary
wellhead outlet according to the prior art, fully outfitted with a
fire-resistant enclosure according to the present invention;
[0037] FIG. 4 is an exploded view thereof;
[0038] FIG. 5 is a perspective view of an exemplary wellhead outlet
according to the prior art, fully outfitted with a fire-resistant
partial enclosure according to the present invention;
[0039] FIG. 6 shows a spacing assembly according to the present
invention;
[0040] FIG. 7 shows the connection means between an exemplary panel
according to the present invention and a prior art wellhead
outlet;
[0041] FIG. 8 shows the connection means between exemplary panels
according to the present invention; and
[0042] FIG. 9 shows a portion of a wellhead outlet that has been
modified to accommodate installation thereto of a fire-resistant
structure according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0043] The ensuing detailed description provides preferred
exemplary embodiments only, and is not intended to limit the scope,
applicability, or configuration of the herein disclosed inventions.
Rather, the ensuing detailed description of the preferred exemplary
embodiments will provide those skilled in the art with an enabling
description for implementing the preferred exemplary embodiments in
accordance with the herein disclosed invention. It should be
understood that various changes may be made in the function and
arrangement of elements without departing from the spirit and scope
of the invention, as set forth in the appended claims.
[0044] To aid in describing the invention, directional terms may be
used in the specification and claims to describe portions of the
present invention (e.g., upper, lower, left, right, etc.). These
directional definitions are merely intended to assist in describing
and claiming the invention and are not intended to limit the
invention in any way. In addition, reference numerals that are
introduced in the specification in association with a drawing
figure may be repeated in one or more subsequent figures without
additional description in the specification in order to provide
context for other features.
[0045] Referring generally to FIGS. 1-9, embodiments of a system
for protecting a wellhead outlet 1 according to the prior art will
be described in detail. FIG. 1 is a perspective view of an
exemplary wellhead outlet 1 according to the prior art. The
wellhead outlet 1 comprises a high pressure bowl 2 having a body 4
and a lid 3. Extending from one side of the body 4 of the wellhead
outlet 1 is a high pressure data port 14. Connected to another side
of the body 4 of the wellhead outlet 1 is a low pressure bowl 9.
The low pressure bowl 9 comprises a body 10 having an exterior
surface 11 and an exposed end 12 having an exterior surface 13. An
atmosphere data port 15 extends from the body 10 of the low
pressure bowl 9. Although one embodiment of a wellhead outlet 1 is
shown and described in this application, it should be understood
that the herein disclosed systems and methods for protecting a
wellhead outlet are applicable, mutatis mutandis, to a wellhead
outlet of any configuration, and that the particular embodiment of
a wellhead outlet 1 shown in the appended figures and described
herein is presented only for discussion purposes.
[0046] The herein disclosed systems and methods, in one respect,
describe enclosures or partial enclosures (see, e.g., enclosure 30
of FIGS. 3A and 3B and partial enclosure 130 of FIG. 5) for
protecting the wellhead outlet 1 from fires. In one embodiment,
this is accomplished by spacing one or more flame-retardant or
protective panels away from exterior surface(s) of the wellhead
outlet 1. These protective panels can be retrofitted to enclose or
partially-enclose existing wellhead outlets, or new wellhead
outlets could be provided that have pre-existing means to attach
the protective panels thereto. Protective panels can be removed
from a wellhead outlet to permit the wellhead outlet to be serviced
or to allow the protective panels to be reused, for example after a
well has run dry or been abandoned. Wellhead outlets may also be
protected from flames by applying flame-retardant coatings, films,
or other materials directly to the parts of the wellhead
outlet.
[0047] As shown in FIGS. 2A and 2B, the enclosure 30 is constructed
by first attaching one or more spacing assemblies 32a-32f to the
exterior surface(s) of one or more parts of the wellhead outlet 1.
In this embodiment of the enclosure 30, six spacing assemblies
32a-32f are used, although one of ordinary skill in the art would
recognize that a lesser or greater quantity of spacing assemblies
can be used based on such factors as the size, dimensions, and
geometry of the wellhead outlet to which the spacing assemblies are
being attached and the weight and geometry of the protective panels
that are being attached to the spacing assemblies. In this
embodiment, the spacing assemblies 32a-32f are attached via
removable hardware (i.e., bolts), so that the spacing assemblies
32a-32f can be removed from the wellhead outlet 1. In alternate
embodiments, the spacing assemblies 32a-32f could be attached to
the exterior surface(s) of one or more parts of the wellhead outlet
1 in other ways, for example by riveting, bonding, or through use
of a suitable adhesive.
[0048] In the embodiment shown in FIGS. 2A and 2B, spacing assembly
32a is attached to the exterior surface 11 of the exposed end 12 of
the body 10 of the low pressure bowl 9, spacing assemblies 32b-32d
are attached to the exterior surface 6 of the bottom side 5 of the
body 4 of the high pressure bowl 2, and spacing assemblies 32e,32f
are attached to the exterior surface 8 of the rear side 7 of the
body 4 of the high pressure bowl 2. The spacing assemblies 32a-32f
thus provide spacing away from the various exterior surfaces of the
wellhead outlet 1 in all three primary axes. In alternate
embodiments, the panels described below may be located directly
adjacent to the exterior surface(s) of the wellhead outlet to which
it is attached.
[0049] FIGS. 3A-4 show an enclosure 30 comprising a plurality of
panels, each of which is connected either directly to one or more
of the spacing assemblies 32a-32f or indirectly to one or more of
the spacing assemblies 32a-32f via one or more additional panels.
In this embodiment, the panels are removably attached to the
spacing assemblies 32a-32f, so that after installation the panels
can be removed from and reattached to the spacing assemblies
32a-32f. In this embodiment, the enclosure 30 comprises a top panel
42, a side panel 44 that is directly connected to spacing assembly
32a, front panels 48,49,50, a bottom panel 55 that is directly
connected to spacing assemblies 32b-32d, and a rear panel 53 that
is directly connected to spacing assemblies 32e,32f. In FIGS. 3A
and 3B (as well as FIGS. 7 and 8), the panels of the enclosure 30
are rendered transparent so that the connections between parts
located behind the panels, as well as the placement of the wellhead
outlet 1 and its parts respective to the panels of the enclosure
30, can be clearly seen. It should be understood that, in many
embodiments, the panels will not actually be transparent. In FIGS.
3A, 3B, and 7, the lines representing the wellhead outlet 1 are
given a lighter weight than that of the lines representing the
parts of the enclosure 30.
[0050] In this embodiment, the panels are a fiber-reinforced
composite comprised of a matrix of SiOC (silicon oxycarbide)
embedded with Nextel.TM. fibers produced by 3M Company of St. Paul,
Minn., U.S.A. In alternate embodiments, the matrix may be any
suitable ceramic material or high-temperature polymer, and the
fibers may be carbon fiber, glass fiber, boron nitride fiber, or
other suitable fibers.
[0051] In this embodiment, top panel 42 has an exterior surface 42a
and a port hole 43 that permits passage of the atmosphere data port
15 of the wellhead outlet 1 therethrough. Front panel 50 has an
exterior surface 50a and a port hole 51 that permits passage of the
high pressure data port 14 of the wellhead outlet 1 therethrough.
Side panel 44 has an exterior surface 44a, front panel 48 has an
exterior surface 48a, front panel 49 has an exterior surface 49a,
side panel 46 has an exterior surface 46a, rear panel 53 has an
exterior surface 53a, and bottom panel 55 has an exterior surface
55a. In this embodiment, each of the exterior surfaces
42a,44a,46a,48a,49a,50a,53a,55a of the respective panels
42,44,46,48,49,50,53,55 is planar. In alternate embodiments, at
least a portion of the exterior surface of at least one panel of
the enclosure is planar. In further alternate embodiments according
to the present invention, the panels of the enclosure may include
no planar portions.
[0052] FIG. 6 depicts the parts of one of the spacing assemblies
(i.e., spacing assemblies 32a-32f). Each of the spacing assemblies
32a-32f comprises a spacing fastener 33 (which in this embodiment
is a bolt), the spacing fastener 33 having a head 34 and a shaft
35, an exterior washer 36, an interior washer 38, and spacing
blocks 40a-40c. The spacing blocks 40a-40c are placed adjacent the
exterior surface of the wellhead outlet 1 and the interior washer
38 is placed adjacent the spacing blocks 40a-40c. In this
embodiment three spacing blocks 40a-40c are used, and each spacing
block 40a-40c is tubiform in shape. In alternate embodiments, a
greater or lesser number of spacing blocks may be used, and/or the
spacing blocks 40a-40c may have a different shape. In this
embodiment, the spacing blocks 40a-40c are made of the same
fiber-reinforced composite material as the panels. In alternate
embodiments, the spacing blocks 40a-40c may be comprised of any
suitable insulative material. In alternate embodiments, the spacing
fastener may comprise some part other than a bolt, for example a
lag, screw, rod, pipe, or tube that is connectable to both the
wellhead outlet 1 and the enclosure 30.
[0053] In this embodiment, the interior washer 38 is located
adjacent to the interior surface of the respective panel. The
exterior washer 36 is located around the shaft 35 of the spacing
fastener 33 and adjacent the exterior surface of the respective
panel, and the shaft 35 of the spacing fastener 33 is passed
through a spacing hole located in the respective panel, the
interior washer 38, and the spacing blocks 40a-40c and then
connected to the wellhead outlet. The head 34 of the spacing
fastener 33 and the exterior washer 36 collectively form the
exterior portion 39 of the spacing assembly, which is located
external to the enclosure 30 (i.e., external to the respective
panel). The spacing blocks 40a-40c and the interior washer
collectively form the interior portion 37 of the spacing assembly,
which is located internal to the enclosure 30 (i.e., internal to
the respective panel). A portion of the shaft 35 of the spacing
fastener 33 is located within the spacing fastener hole in the
respective panel. FIG. 7 shows the connection of the side panel 44
to the exterior surface 13 of the exposed end 12 of the body 10 of
the low pressure bowl 9 of the wellhead outlet 1 via the spacing
assembly 32a.
[0054] As best seen in FIG. 4, rear panel 53 includes spacing
fastener hole 54a and spacing fastener hole 54b, which accommodate,
respectively, spacing assembly 32f and spacing assembly 32e; bottom
panel 55 includes spacing fastener holes 56a-56c, which
accommodate, respectively, spacing assemblies 32b-32d; and side
panel 44 includes spacing fastener hole 45, which accommodates
spacing assembly 32a. As noted previously, the side panel 44 is
directly connected to the wellhead outlet 1 via spacing assembly
32a, the bottom panel 55 is directly connected to the wellhead
outlet 1 via spacing assemblies 32b-32d, and the rear panel 53 is
directly connected to the wellhead outlet via spacing assemblies
32e,32f. These panels 44,53,55 are then connected to the additional
panels 42,46,48,49,50 via spacing blocks and panel attachment
fasteners to form the enclosure 30. All of the spacing blocks and
panel attachment fasteners of the enclosure 30 are shown in the
exploded view of FIG. 4, but for purposes of readability these
parts are not labeled and all explode lines are not included.
[0055] FIG. 8 shows an exemplary corner of the enclosure 30, where
top panel 42, side panel 44, and front panel 48 are joined together
via a panel attachment block 60. In this embodiment, the block 60
is cubic in shape and has internal threading located through the
center of all three major axes thereof, with the internal threading
terminating at three adjacent faces of the block 60 at fastener
holes 61a-61c (fastener hole 61c labeled in FIG. 3A). Exterior
washer 63a is placed around panel attachment fastener 62a, which is
used to secure top panel 42 to the fastener hole 61a of block 60;
exterior washer 63b is placed around panel attachment fastener 62b,
which is used to secure side panel 44 to the fastener hole 61b of
block 60; and exterior washer 63c is placed around panel attachment
fastener 62c, which is used to secure front panel 48 to the
fastener hole 61c of block 60. In alternate embodiments, the panels
may be directly connected together without the use of corner
blocks.
[0056] In some embodiments, as shown in FIG. 9, one or more
exterior surfaces of a prior art wellhead outlet 1 may be tapped so
that these surfaces are outfitted with internally threaded holes 70
for accommodation of the shaft 35 of the spacing fastener 33
therein. In alternate embodiments according to the present
invention, the wellhead outlet may be provided with tapped holes
already located in the exterior surface(s) thereof for
accommodating the spacing fastener(s), and the wellhead outlet
provided along with the necessary parts of the enclosure as part of
the protective system for the wellhead outlet.
[0057] The embodiment of the enclosure 30 shown in FIGS. 3A-4 fully
encloses the wellhead outlet 1 therein, with the exception of the
port holes 43,51 that permit the atmosphere data port 15 and high
pressure data port 14, respectively, to pass therethrough and exit
the enclosure 30. In embodiments where there is a gap left between
one or both of the port holes 43,51 and the respective port 14,15,
said gap is preferably filled with a flame-retardant material, for
example a commercially-available fire blanket. One example of a
suitable, commercially-available fire blanket is the Fiberfrax S
Durablanket which is produced by Thermal Products Company, Inc. of
Norcross, Ga., U.S.A.
[0058] In some applications, it may not be necessary to fully
enclose all sides of the wellhead outlet 1 within an enclosure.
FIG. 5 shows a partial enclosure 130 for a wellhead outlet that
utilizes only some of the parts of the full enclosure 30. For
example, in this embodiment the partial enclosure 130 utilizes only
the side 46, rear 53, and bottom 55 panels, spacing assemblies
32b-32f (spacing assemblies 32d-32f not shown in FIG. 5), and some
panel attachment blocks and accompanying panel attachment
fasteners.
[0059] One purpose of the enclosure 30 or partial enclosure 130 is
that it is designed to enable the wellhead outlet 1 to withstand
exposure to fire or other sources of high heat without seal
failure. The enclosure 30 is designed to protect the seals of the
wellhead outlet 1--e.g., the high pressure bowl 2 and the fiber
optic feedthrough assembly (not labeled), which is located interior
to the low pressure bowl 9--from significant leakage after exposure
to fire.
[0060] In order to demonstrate this capability, the wellhead outlet
1 (i.e., the end connection) was fitted with the enclosure 30 and
successfully tested using the following test protocol: [0061] An
exterior surface of the enclosure 30 is fitted with at least three
thermocouples, each thermocouple being located within the center of
1.5-inch (3.8 cm) cubic carbon steel calorimeter blocks, the
thermocouples and calorimeter blocks being spaced apart from each
other within the plane of the exterior surface of the enclosure 30
by no more than 12 inches (30.5 cm); [0062] The wellhead outlet
system is completely filled with water; [0063] The wellhead outlet
system is pressurized to at least 75% of its rated working pressure
(for example, if an end connection is rated at 2000 psig (13.8
MPa), the system should be pressurized to at least 1500 psig (10.3
MPa)); [0064] A fire is established in the vicinity of the end
connection to be tested (i.e., the exterior surface of the
enclosure) and the flame temperature is monitored during the "burn
period," which is no less than 30 minutes in duration from the time
that the fire is first established: [0065] The average temperature
reading of the thermocouples must reach 1400 degrees F. (761
degrees C.) within 2 minutes from the time that the fire is
established; [0066] The average temperature reading of the
thermocouples must be maintained between 1400 and 1800 degrees F.
(761 and 980 degrees C.), with no reading less than 1300 degrees F.
(704 degrees C.), until the average calorimeter temperature reaches
1200 degrees F. (650 degrees C.). The average calorimeter
temperature shall reach 1200 degrees F. (650 degrees C.) within 15
minutes from the time that the fire is established. After those
average calorimeter temperatures are reached, for the remainder of
the duration of the burn period, the calorimeters shall maintain a
minimum average temperature of 1200 degrees F. (650 degrees C.),
and no calorimeter reading shall be below 1050 degrees F. (565
degrees C.); [0067] The wellhead outlet system is then cooled to no
more than 212 degrees F. (100 degrees C.), and the system is
depressurized; [0068] The pressure in the wellhead outlet system is
then increased to no less than 75% of its rated working pressure,
and this test pressure is held for a minimum of 5 minutes; [0069]
The water leakage rate from the end connection is measured during
the burn and cooldown periods and during the 5 minute period after
depressurization and repressurization, with a "pass" result for
this test being an end connection leakage rate of no greater than 1
ml/in. per minute of mean primary gasket circumference (i.e., the
mean circumference of the primary gasket of the tested end
connection).
[0070] It should be appreciated that the foregoing is presented by
way of illustration only, and not by way of any limitation, and
that various alternatives and modifications may be made to the
illustrated embodiments without departing from the spirit and scope
of the present invention.
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