Note: Descriptions are shown in the official language in which they were submitted.
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STUFFING BOX LEAK CONTAINMENT APPARATUS
This application is a division of Canadian Patent Application No. 2,742,446
filed
June 8, 2011 for Stuffing Box Leak Containment Apparatus.
FIELD OF INVENTION
[0001] The present invention relates to an apparatus for containing leaks
from a stuffing
box at a wellhead as well as methods for using the same.
BACKGROUND
[0002] A common problem with wellhead production equipment is that many of the
structures
associated with a wellhead, such as a stuffing box and polished rod, are
susceptible to leaking.
As a result, the surrounding environment can be exposed to oil or other fluids
which can have
deleterious effects on local plants and wildlife. To solve this problem,
devices are positioned
around portions of the stuffing box and well head to contain the leaking
material. However,
prior containment devices suffer from one or more of the following problems:
(1) tedious
assembly of the device on the wellhead and tedious removal; (2) disassembly of
the device to
access stuffing box; (3) disassembly of the device to visually inspect the
stuffing box; (4) lack of
a proper liquid seal; and (5) difficulty maintaining the device in a fixed
position on the well head.
As a result of these problems, wellhead operators are more reluctant to
utilize containment
devices ultimately leading to an increase in pollution.
[0003] The present invention seeks to alleviate these problems by
providing a
contaimnent apparatus that (1) is easily assembled on the wellhead, (2)
provides a liquid tight
seal around the stuffing box (3) provides easy access to the stuffing box, and
(4) allows for visual
inspection of the stuffing box while the apparatus is in place. Such an
invention promotes
environmentally conscious behavior without the detriment of significant
increases in cost and
time.
SUMMARY
[0004] As known to those skilled in the art, wellhead production
equipment typically
includes a stuffing box carried on the nipple of a pumping tee. The present
invention provides a
leak prevention apparatus suitable capturing leaks originating at the stuffing
box. The apparatus
includes a first gasket positioned on the nipple and a seal ring positioned
over the first gasket.
The seal ring has an upper end carrying an external circumferential groove and
a lower end with
an outwardly projecting flange. The flange interrupted by at least two slots.
The apparatus also
includes a stabilizer bar having at least two upwardly extending flanges. When
positioned on the
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pumping tee, the stabilizer bar's upwardly extending flanges extend through
the slots of the seal
ring. Positioned within the circumferential groove of the seal ring is a
second gasket. To capture
any leaks, the apparatus includes a liquid tight containment vessel comprising
a first half shell
and a second half shell. Alignment of the first half shell with the second
half shell defines the
liquid tight containment vessel. The containment vessel has a lower opening.
The lower
opening cooperates with the second gasket to provide a liquid tight seal when
the containment
vessel is positioned on the seal ring. Additionally, the lower opening carries
two tabs. When the
liquid tight containment vessel is positioned on the seal ring, the tabs are
adjacent to the
upwardly extending flanges of the stabilizer bar. In a preferred embodiment, a
top is placed on
the vessel to completely enclose the stuffing box. The top has an upper
opening to receiving a
polished rod extending from the stuffing box.
[0005] In another embodiment, the present invention provides a leak
prevention
apparatus suitable for mounting on the top of a stuffing box. The stuffing box
has an upper lube
cap with at least one threaded hole and a polished rod passing through the
upper lube cap. The
leak prevention apparatus includes a first gasket positioned on the upper lube
cap. The first
gasket substantially conforms to the geometry of the surface of the upper lube
cap and has at
least a first hole corresponding to the threaded hole in the upper lube cap
and a second hole that
permits passage of the polished rod. The leak prevention apparatus further
includes a liquid tight
containment vessel wherein alignment of a first half shell with a second half
shell defines the
liquid tight containment vessel. The containment vessel has at least a first
lower opening and a
second lower opening corresponding and aligning with the threaded hole in the
upper lube cap
such that passage of a thread bolt through the first lower opening secures the
liquid tight
containment vessel to the upper lube cap. Cooperation of the first gasket and
the first lower
opening provides a liquid tight seal.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1A is a front view of a stuffing box assembly on a wellhead.
[0007] FIG. 1B is a perspective view of a stuffing box assembly on a
wellhead.
[0008] FIG. 2A is an exploded perspective view of a preferred embodiment
of a
containment vessel.
[0009] FIG. 2B is an exploded perspective view of a preferred embodiment
of a topper
for the containment vessel.
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[0010] FIG. 2C is a perspective view of a preferred embodiment of the
containment
vessel with the topper.
[0011] FIG. 3 is an exploded, perspective view of the components of a
preferred
embodiment of a seal subassembly.
100121 FIG. 4A is an exploded, perspective view depicting the positioning
of the first
gasket 112 on the nipple of the pumping tee below the stuffing box.
100131 FIG. 4B is an exploded, perspective view depicting the positioning
of the seal ring
114 on the nipple of the pumping tee below the stuffing box.
[0014] FIG. 4C is an exploded, perspective view depicting the positioning
of the
stabilizer bar 116 on the nipple below the seal ring 114.
[0015] FIG. 4D is an exploded, perspective view depicting the positioning
of the second
gasket 118 in the circumferential groove of the seal ring 114.
[0016] FIG. 5 is a perspective view of a preferred embodiment of the
containment vessel
in an open configuration with the seal subassembly positioned on the welthead.
100171 FIG. 6 is a front view of a preferred embodiment of the
containment vessel in the
open position depicting the orientation of the containment vessel 30 with
respect to the
components of the seal subassembly.
[0018] FIG. 7 is a front view of the top-mounting embodiment of the
containment
apparatus in an open configuration and positioned on the wellhead above the
stuffing box.
100191 FIG. 8 is an exploded view of a gasket being positioned on the
lube cap of a
stuffing box for the top-mounting embodiment.
100201 FIG. 9 represents a top-view of the preferred gasket design for
use in connection
with a Huber HerculesTM or SkinnerTM stuffing box for the top-mounting
embodiment of the
containment apparatus.
[0021] FIGS. 10 and 11 represent top-views of alternative gasket designs
for use in
connection with a Skinner Cross TwinTm stuffing box for the top-mounting
embodiment of the
containment apparatus.
[0022] FIG. 12 represents a top-view of the preferred gasket design for
use in connection
with a RatiganTM stuffing box for the top-mounting embodiment of the
containment apparatus.
[0023] FIG. 13 represents an exploded, perspective view of the gasket and
containment
vessel mounted on the lube cap of a stuffing box.
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[0024] FIG. 14 is a side view of a fully assembled embodiment of
the containment
apparatus on the wellhead with optional tubing extending from the drain port
to a storage
a
container.
DETAILED DESCRIPTION
[0025] The present invention relates to a containment apparatus for
containing leaks from
a stuffing box at a wellhead. Depending on the configuration of the wellhead
and the type of
stuffing box utilized, the containment apparatus may be secured at a location
below or above the
stuffing box. The present invention strategically positions gasket material to
provide a liquid-
tight seal between the containment apparatus and the stuffing box thereby
maximizing fluid
retention in the containment vessel. The present invention provides the
ability to stabilize and
maintain the containment vessel in a vertical configuration on the wellhead.
This configuration
overcomes the tendency of prior art devices to become loose leading to a loss
of seal and
undesirable apparatus contact with the polished rod or other components of the
stuffing box.
[0026] The present invention also provides the ability to access
the stuffing box and
polish rod without completely removing the containment apparatus from the
wellhead.
Similarly, the present invention permits visual inspection of the stuffing box
and polished rod
without removing any portion of the apparatus. These advantages and others
will become
apparent upon examination of the proceeding written description and drawings.
[0027] The stuffing box containment apparatus 10 of the present
invention can be divided
into essentially three primary components: (1) a containment vessel 30, the
individual parts of
which are depicted in FIG. 2A and 2C; (2) a topper 80 or lid, the individual
parts of which are
depicted in FIG. 2B and 2C; and (3) a seal subassembly 110, the individual
parts of which are
depicted in FIG. 3.
[0028] To provide a frame of reference for the present invention,
FIG. 1 A and 1B depict
a typical stuffing box 12 on a wellhead. In relevant part, the stuffing box
comprises a polished
rod 14, a stuffing box base 16, a nipple 18, a pumping tee 20 and a lube cap
22.
[0029] Referring now to FIG. 2A, a preferred embodiment of a
containment vessel 30 is
illustrated. When assembled on stuffing box 12, a first half shell 32 and a
second half shell 34
form containment vessel 30. As first and second half shells 32, 34 are
essentially mirror images,
the common features will be discussed with respect to first half shell 32
noting any differences
between half shells 32, 34. First half shell 32 contains a floor portion 36,
an upstanding wall
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portion 38, a collar portion 40 and a pair of mating surfaces 42a, 42b. Mating
surfaces 42a, 42b
= define the transition from floor portion 36 and upstanding wall portion
38 and further provide the
contact surfaces between first half shell 32 and second half shell 34. Mating
surfaces 42a, 42b
extend down to collar portion 40 terminating adjacent to a circumferential
groove 46 in collar
portion 40. Additionally, a recessed channel 48 is defined in each mating
surface 42a, 42b of the
first half shell 32 and extends the length of mating surfaces 42a, 42b
terminating in alignment
with the circumferential groove 46 of the collar portion 40. Positioned within
channel 48 is a
first sealing material 50. Second half shell 34 contains a ridge 52 on its
mating surfaces 43a, 43b
(see FIG. 5) that corresponds in position to channel 48 of the first half
shell 32. Thus, when first
and second half shells 32, 34 are combined to form containment vessel 30,
channel 48 receives
ridge 52 compressing sealing material 50 therein to provide a liquid tight
seal.
[0030] Collar portion 40 carries two tabs 60a, 60b. As can be seen
in FIG. 2A, tabs 60a,
60b are set back from mating surfaces 42a, 42b such that when half shells 32,
34 are joined, a
space exists between opposing tab surfaces providing for engagement with seal
subassembly 110
(discussed further herein below with respect to FIGS. 5 and 6). Tabs 60a, 60b
extend laterally in
opposite directions from the collar portion 40. Each tab 60a, 60b has an
opening 61a, 61b
suitable for receiving a bolt or pin. Additional attachment points are
provided along the length
of each mating surface 42a, 42b, 43a, 43b. Preferred attachment points are
outwardly projecting
lobes or ears 63 each having at least one opening 64 capable of receiving a
bolt or pin to tightly
secure the first half shell 32 to the second half shell 34. As depicted, lobes
63 on one half shell
32, 34 correspond to the lobes 63 on the other half shell.
[0031] Continuing with FIG. 2A, first half shell 32 and second half
shell 34 each
preferably provide latching components such as, but not limited to, a hinge 66
and buckle 68 to
permit separation of the half shells 32, 34 without removal from the wellhead.
In this aspect,
hinge connection 66 allows the containment vessel 30 to be opened by releasing
the buckle 68
thereby permitting access to the stuffing box 12 without requiring the vessel
30 to be removed
from the wellhead. Those skilled in the art will recognize that shells 32, 34
could be coupled in a
number of different manners while retaining the advantage of access to
stuffing box 12 without
removal of vessel 30. For example, two buckles could be utilized that permit
one of the half
shells to be selectively removed for access to stuffing box 12 or replacement
upon damage.
Furthermore, mating surfaces 42a, 42b could be adapted to provide additional
lobes 63 with
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openings 64 in place of the buckle 68. Containment vessel 30 can additionally
contain a number
of other features such as a drain port 70 and a plug 72 adapted to receive an
optional float or kill
switch.
[0032] Referring now to FIG. 2B, containment apparatus 10 preferably
includes a
transparent lid or topper 80 for containment vessel 30. Although preferred,
transparency is
merely optional. Transparency of topper 80 permits the visual inspection of
stuffing box 12
without removing any portion of the apparatus 10. In a preferred embodiment,
the topper 80 is
divided into half portions 82a, 82b which can be secured together by a variety
of mechanisms.
In a preferred embodiment, half portions 82a, 82b are secured by joining a
hook 84 on one half
portion to a tab 86 on the opposite half portion. In order to provide a liquid
seal, each half
portion 82a, 82b provides a flange 88 extending from opposite edges of each
half portion. Upon
attachment of the half portions 82a, 82b, each flange 88 extends under the
opposing half portion
thereby providing a barrier at the joined edges of the half portions.
Alternatively, one half
portion may carry both flanges 88 which slide under the other half portion to
provide the desired
barrier. When assembled, topper 80 provides an upper opening 90 sufficient to
permit passage
of polished rod 14. Upper opening 90 carries recessed grooves or channels 92a,
92b on each half
portion 82a, 82b suitable for receiving protective material 94, such as felt.
Protective material 94
should extend past the edges of the channels 92a, 92b in order to prevent
polished rod 14 from
contacting the edges of upper opening 90. Topper 80 preferably has a height
sufficient to clear
the top of stuffing box 12. More preferably, topper 80 has a height between
10" and 20".
100331 Topper 80 can be attached to containment vessel 30 in a number of
different
manners which will be apparent to those skilled in the art. Preferably, topper
half portions 82a,
82b carry a lower rim 96a, 96b extending horizontally from the bottom edge of
the topper half
portions 82a, 82b. Each lower rim 96a, 96b carries one or more downwardly
projecting tabs 98.
(Only the upper surface of tabs 98 is visible in FIG. 2A and FIG. 2C.)
Downwardly projecting
tabs 98 are configured to be received by one or more bayonet mount receiving
slots 100 spaced
accordingly on an upper rim 102a, 102b of the containment vessel 30 (see FIG.
2A). Lower rim
96a, 96b of the topper 80 is placed on upper rim 102a, 102b such that
downwardly projecting
tabs 98 are aligned with the bayonet mount receiving slots 100. The topper 80
is locked in place
by turning it clockwise to move tabs 98 into the proper position with the
bayonet mount
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receiving slots 100. FIG. 2C depicts the containment vessel 30 and topper 80
as properly joined
for use on a wellhead.
100341 Referring now to FIG. 3, the components of a preferred embodiment
of the seal
subassembly 110 will be described. In this embodiment, seal subassembly 110
comprises a first
gasket 112, a seal ring 114 having inner and outer walls 122 and 125, a
stabilizer bar 116 and a
second gasket 118. First gasket 112 is preferably a foam gasket of a size
sufficient to cover
nipple 18 between pumping tee 20 and stuffing box base 16 as demonstrated in
FIG. 4A. More
preferably, first gasket 112 is approximately 7/8" x 9.35" or 10.92"
(depending on the
circumference of the stuffing box nipple) x 3/8". As depicted inner wall 122
is offset from outer
wall 125. In the preferred embodiment, downwardly sloping ribs 123 connect
inner wall 122 to
outer wall 125. This configuration provides strength while reducing weight;
however, other
configurations for joining inner and outer walls will also perform
satisfactorily.
[0035] Continuing with seal subassembly 110, seal ring 114 is positioned
around nipple
18 overlying first gasket 112 as depicted in FIG. 4B. Seal ring 114 has an
external
circumferential groove 120 carried by outer wall 125 and extending around the
upper end of seal
ring 114. Seal ring 114 inner wall 122 provides the portion of the seal ring
114 that will contact
first gasket 112 on nipple 18. To permit positioning of seal subassembly 110
as close as possible
to the lower portion of stuffing box 16, the overall height of wall 122 is
less than the height of
outer wall 125. The difference in height provides a void space 124 in
assembled seal ring 114
suitable for receiving the lower portion of stuffing box 16.
[0036] Seal ring 114 also has an outwardly projecting flange 126 that
extends around the
lower end of seal ring 114. Flange 126 is interrupted by at least one slot
128. Preferably, flange
126 is interrupted on opposite sides to provide a pair of slots 128. As
depicted in FIGS. 3 and
4B, seal ring 114 comprises two half portions 114a, 114b that are joined
around nipple 18. Seal
ring halves 114a, 114b can be joined through a variety of different
mechanisms, but preferably
bolts 127 are used to join seal ring 114 around nipple 18 of the wellhead.
[0037] In an alternative embodiment (not depicted), a belt gasket can be
used in lieu of
the seal ring 114. The belt gasket is preferably a 3.5" gasket that extends
from the top portion of
the pumping tee 20 to the bottom portion of the stuffing box base 16. Thus,
this embodiment can
be used in wellheads where the nipple 18 is not large enough to permit
attachment of the seal
ring 114. Alternatively, this embodiment can be used where the stuffing box
base 16 is too large
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to be received by void 124. In this embodiment, parting line gaskets (not
shown) are placed over
the portion of mating surfaces 42a and 42b such that a portion, preferably
1/8", of the gasket
material protrudes into the cylindrical passage defined by collar 40.
[0038] Turning now to FIG. 4C, a stabilizer bar 116 is provided.
Stabilizer bar 116
provides a stable, secure base for positioning containment vessel 30 on the
wellhead. Thus,
stabilizer bar 116 prevents containment vessel 30 from slipping downward or
changing position.
To this end, stabilizer bar 116 is positioned on pumping tee 20 just below
nipple 18 such that
laterally projecting flange 126 of seal ring 114 rests on the top surface of
stabilizer bar 116.
Stabilizer bar 116 is secured to the pumping tee by two bolts 129 extending
through openings
130 at the ends of each half 116a, 116b of stabilizer bar 116. Stabilizer bar
116 further provides
at least two sets of upwardly extending flanges 132 with each flange 132
having an opening 133
defined therein. In the preferred embodiment, each half 116a, 116b carries a
pair of flanges 132.
Stabilizer bar 116 is oriented on the pumping tee such that upwardly extending
flanges 132 are
received within slots 128 of seal ring 114.
[0039] As depicted in FIG. 4D, a second gasket 118 is placed in the
circumferential
groove 120 of the seal ring 114. The second gasket 118 is preferably 1/4" x
15.74" x 1/8".
Second gasket 118 will ultimately mate with sealing material 50 present in
channel 48 of first
half shell 32 and will further align with circumferential groove 46 on collar
portion 40 of
containment vessel 30.
[0040] FIGS. 5 and 6 depict containment vessel 30 positioned on seal
subassembly 110
with stabilizer bar 116 positioned beneath seal subassembly 110. When properly
position tabs
60c, 60d of second half shell 34 are aligned with upwardly extending flanges
132 of stabilizer
bar 116. Upon alignment of second half shell 34 with the components of the
seal subassembly
110, first half shell 32 can be joined to form containment vessel 30. Thus,
tabs 60a, 60b of
second half shell 34 are aligned with upwardly extending flanges 132 of
stabilizer bar 116. As
such, each set of flanges 132 are flanked by tabs 60a, 60b, 60c and 60d
thereby aligning
openings 61a-d with openings 133. A bolt or pin 134 can then be placed through
the aligned
openings to secure first half shell 32 and second half shell 34 to stabilizer
bar 116. Accordingly,
stabilizer bar 116 supports containment vessel 30 with or without use of seal
ring 114.
[0041] Additionally, ridges 52 on mating surfaces 43a, 43b of second half
shell 34 are
aligned with and compress sealing material 50 contained in channels 48 on
mating surfaces 42a,
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42b of first half shell 32 creating a liquid tight seal at the junction seam
of the two halves of the
containment vessel 30. Moreover, channel 48 of first half shell 32 terminates
at circumferential
groove 120 of seal ring 114 such that sealing material 50 disposed in channel
48 will contact
second gasket 118 in circumferential groove 120. External circumferential
groove 120 of seal
ring 114 also aligns with circumferential groove 46 of collar portions 40 on
first half shell 32 and
second half shell 34. Finally, buckle components 68 are secured and bolts or
pins are positioned
through the now aligned openings 64 to further secure the half shells
together.
[0042] In an alternative embodiment, containment apparatus 10 is secured
above stuffing
box 12 as depicted in FIGS. 7, 8, and 13. In this top-mounting embodiment,
containment vessel
300 has been modified to provide a fluid tight seal to upper lube cap 22. As
such, in this
embodiment containment vessel 300 does not require a collar portion 40.
Instead, mating
surfaces 342a, 342b, 343a, 343b of the half shells 332, 334 terminate at a
lower opening 340.
Lower opening 340 permits passage of the polished rod 14 and is flanked on
either side by a pair
of second openings 341a, 341b. Second openings 341a, 341b permit passage of a
bolt 344 to
secure the containment vessel 300 to lube cap 22.
100431 Second, a single gasket 346 is used in place of the seal
subassembly 110
described in the previous embodiment. Gasket 346 is placed on the upper lube
cap 22 as
depicted in FIG. 8 and preferably conforms to the geometry of the surface of
the upper lube cap
22. FIGS. 9 ¨ 12 provide examples of gaskets 346 which conform to a variety of
common lube
caps 22. Once gasket 346 is in place on lube cap 22, containment vessel 300 is
secured to lube
cap 22 and gasket 346 by bolts 344 placed in second openings 341a, 341b as
shown in FIG. 13.
Thus, sealing material 350 in channel 348 of first half shell 332 mates with
gasket 346 on lube
cap 22 providing a liquid tight seal. All other features described above with
respect to topper 80
and containment vessel 30 are common to the top-mounting embodiment.
100441 FIG. 14 depicts an optional storage container 150 suitable for use
in conjunction
with either embodiment discussed above. As depicted, optional storage
container 150 is in fluid
connection with the tee mounted stuffing box containment apparatus 10. In this
embodiment, a
hose 152 provides a fluid connection between containment vessel 30 and
additional storage unit
150. Hose 152 is connected to containment vessel 30 via an adaptor 154
extending from drain
port 70.
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[0045] Containment vessel 30 or 300, seal ring 114 and stabilizer bar 116
can be
manufactured from any thermoplastic or thermosetting plastic material suitable
for injection
molding including, but not limited to polyurethane, polyamide, polyethylene,
polypropylene,
polystyrene, acrylonitrile butadiene styrene or polyvinyl chloride. Preferably
polyurethane will
be used for containment vessel 30 and 300. Topper 80 is preferably transparent
polycarbonate,
but can be manufactured using any durable plastic material. Seal ring 114 and
stabilizer bar 116
are preferably polycarbonate.
[0046] Gaskets 112, 118, 346 and sealing material 50, 350 are preferably
a cellular
polyurethane foam such as PoronTM. Alternatively, a closed cellular foam such
as a Neoprene-
EDM-SDRTm blend (PAX P42BTm) will perform satisfactorily. Additionally, the
gaskets can be
replaced with a high-temp neutral cure silicone such as an RTV silicone or Dow
Comingm
adhesive sealant. One example of a RTV type silicone material would include,
but is not limited
to, Dow Corning Product no. 3145 MIL-A-46146, containing 5.0 to 13.0 weight
percent
methyltrimethoxysilane.
[0047] Various connectors can be used in the above described embodiments
including,
but not limited to standard threaded bolts, spring-loaded hitch pins, D-shaped
snapper pins, semi-
tubular rivets, split rivets, and thumb screws.
[0048] In addition, a grounding system should be applied to the
apparatus. In a preferred
embodiment a grounding clamp is attached to the wellhead below the pumping tee
with a
grounding wire extending to one of the bolts on the containment vessel 30 and
secured thereto.
[0049] The present invention also provides a method for containing leaks
at a stuffing
box. The steps of the method are outlined with reference to FIGS. 1A, 4A-D, 5
and 6. The
preferred characteristics of the parts used in this method are outlined in
detail above. Referring
to FIG. 1A, the first step requires cleaning of stuffing box base 16, nipple
18 and top of pumping
tee 20. These areas should be dry and free from all oil, grease and dirt
before proceeding to the
second step.
[0050] Referring now to FIG. 4A, the second step requires applying first
gasket 112 to
nipple 18 of stuffing box 12. Once first gasket 112 is in place, the third
step, as demonstrated in
FIG. 4B, joins halves 114a, 114b of seal ring 114 around nipple 18. Bolts 127
are preferably
used to securely unite halves 114a, 114b thereby forming sealing ring 114.
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[0051] In the fourth step, stabilizer bar 116 is positioned on the top
portion of pumping
tee 20 as depicted in FIG. 4C. When properly positioned on the pumping tee,
stabilizer bar 116
supports laterally projecting flange 126 of seal ring 114. Additionally,
upwardly extending
flanges 132 of the stabilizer bar 116 are received by slots 128 in laterally
projecting flange 126.
The two halves 116a, 116b of the stabilizer bar 116 are then secured by
tightening the bolts 129
projecting through the openings in the ends of the stabilizer bar 116.
[0052] In the fifth step, second gasket 118 is positioned within
circumferential groove
120 of seal ring 114 as shown in FIG. 4D. Following the fifth step, the
components of the seal
subassembly 110 are in place and are able to receive the containment vessel
30.
[0053] Referring now to FIGS. 5 and 6 for the sixth step, the first and
second shell halves
32, 34 of the containment vessel 30 are positioned on seal subassembly 110.
Collar portion 40 of
each half shell is positioned on the laterally extending flange 126 of the
seal ring 114 such that
the tabs 60a, 60b, 60c, 60d of the shell halves 32, 34 abut upwardly extending
flanges 132 of
stabilizer bar 116. In other words, each pair of opposing tabs (60a, 60c and
60b, 60d) are
separated by upwardly extending flanges 132 and the openings in each (61a-d,
133) should be
aligned as described above. Shell halves 32, 34 are first secured by fastening
the buckle 68.
Bolts 65 are then positioned through openings 64 and tightened to ensure that
ridge 52 is
securely positioned against sealing material 50 in channel 48 of the abutting
mating surfaces 42a,
43a and 42b, 43b. If seam 54, defined by the abutting mating surfaces 42a, 43a
and 42b, 43b, is
properly sealed, then tabs 60a, 60b, 60c, 60d can be bolted to upwardly
extending flanges 132 of
the stabilizer bar 116.
[0054] If seal ring 114 has been omitted, then collar portion 40 of each
half shell will be
supported by the upper surface of stabilizer bar 116. As described above, tabs
60a, 60b, 60c, 60d
of the shell halves 32, 34 abut upwardly extending flanges 132 of stabilizer
bar 116. Thus,
containment vessel will be secured to and supported by stabilizer bar 116.
Contact of sealing
material 50 in channel 48 with the belt gasket substituted for seal ring 114
will provide the
requisite fluid tight seal.
[0055] Finally, topper halves 82a, 82b can be joined as described above
and mounted to
the containment vessel 30 by inserting downwardly projecting tabs 98 into the
bayonet mount
receiving slots 100 and turning the topper 80 clockwise. If containment vessel
30 has been
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properly mounted to seal subassembly 110, polished rod 14 should extend
through upper opening
90 of topper 80 without contacting the edges of opening 90.
100561 In an alternative embodiment, the present invention also provides
a method for
containing leaks from a polished rod 14 and lube cap 22 by positioning
containment vessel 300
on top of lube cap 22. In this method, lube cap bolts 344 are removed followed
by thoroughly
cleaning lube cap 22 to remove all grease, dirt and oil from the surface. A
gasket 346 is then
applied to the lube cap 22 as depicted in FIG. 8. Gasket 346 is of a size and
geometry that
substantially conforms to the surface of lube cap 22. With reference to FIG.
7, first and second
shell halves 332, 334 of the containment vessel 300 are then joined together
such that the
polished rod extends through first opening 340. The buckle 368 is then secured
and bolts 344
are positioned in second openings 341a, 341b to secure containment vessel 300
to lube cap 22.
Bolts 365 are then applied to openings 364 to ensure that ridge 352 is
securely positioned against
sealing material 350 in channel 348 of abutting mating surfaces 342a, 343a and
342b, 343b.
Topper 80 is then applied to containment vessel 300 in the same manner as
described above.
100571 Both methods describe above can also include the additional step
of connecting
the containment vessel 30 (or 300) to additional storage unit 150. As depicted
in FIG. 14, a hose
152 provides fluid connection adaptor 154 extending from drain port 70 of
containment vessel 30
to storage container 150.
[0058] Other embodiments of the current invention will be apparent to
those skilled in
the art from a consideration of this specification or practice of the
invention disclosed herein.
However, the foregoing specification is considered merely exemplary of the
current invention
with the true scope and spirit of the invention being indicated by the
following claims.
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