Note: Descriptions are shown in the official language in which they were submitted.
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Backqround of the Invention
1. Field of the Invention
The present invention relates to piping and piping
control systems, but more particularly, the present invention
relates to the detection of leaks in the fitting portion of
piping systems and the subsequent closure of valves and like
controls coincident with the occurrence of such a leak. Even
; more particularly, the present invention relates to a portable
apparatus ~or detecting leaks in a suspect fitting portion of
a pipeline with a bladder structure being portable and attachable
to any existing piping system in a sealable fashion, the bladder
thereafter collec-ting leaks.
2. General Backaround and Prior Art
In all piping systems, there is utilized generally a
, number of "fittings" whic'h are used to configure the pipeline
or piping system to a desired chemical plant, or to the terrain
across which it is flowing, or otherwise to change the pipelines
configuration and position. Such fittings are known in the art
as elbows, tees, crosses, valves~ flanges and the like. A
fitting is generally referred to hereinafter as any portion of a
pipeline which is connectable to a normal pipe joint, the fitting
being a portion of the pipeline which can create turbulence and
which can be a ~spot for potential leaks-
Leaks in fittings are generally created by corrosionor mechanical deterioration. ~his is often seen in t'he oil and
gas industry where natural gas and/or oil flowing from a well
is often comblned with sand and the flowing produces a sandblast-
ing effect. This sandblasting effect especially eats away at
elbows, tees, choke jackets, and valves when the pipeline makes
a turn. It is known in the art that -turbulence is increased at
such turning points in the pipeline.
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In the production of natural gas, a well is normally
drilled ~ith a length of pipe known as a "drill string"- The
drill pipe is individually made up of sections which can be,
for example, thirty feet (30'). The drill pipe is enclosed
normally in a casing which is also welfed or jointed. Casing
is then cemented into place from the bottom up~ At the head
of the casing, the crew installs a master ~alve that may be
closed quickly and surely to shut off the flow of gas. Above
this valve is placed a "Christmas tree". A Christmas tree is
merely an assembly of pipes and valves that allows the gas to
flow into gathering lines. These gather the output of several
wells and carry the fuel to the cross-country pipelines for
remote transmission of the gas. It is to this general field
that the present invention is directed.
Ssveral devices have been patented which have attempted
; to provide a method for the detection of leaks in flow lines and
in fittings which have been corroded by chemical or weather attack,
or mechanically deteriorated as is the case with sand/gas com-
binations. The following table provides a list of some prior art
devices which have been patented.
PRIOR ART PATE~TS
U.S. Patent ~o. Inventor Issue Date
2,280,140 J. H. Wilson April 21, 1942
2,607,225 P. H. Biscoe January 23, 19~8
2,765,801 F. E. Selim October 9, 1956
~2,937,520 A. Bell May 24, 1960
3,339,415 W. Wild September 5, 1967
3,399,728 A. R. Taylor September 3, 1968
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3. General Discussion of the Present Invention
The present invention,provides a simple and
economica] system for the dete<ction of minute leaks in flow
lines, and a method for the shut-off of flow within the line
for a catastrophic failure of the line occurs. Such a device
is especially important in the oil and gas industry, and in
the transmission of natural gas where pressures developed
within flow lines can be quite high.
The present invention provides a portable bladder
which can be quickly attached and jacketed into position
around a particular fitting in any existing piping system
which fitting may be suspect or subject to damage. Thus, the
bladder could be placed around the fittings which would ex- -~
perience a maximum amount of turbulence, mechanical deterior-
ation, or corrosion.
The present invention solves all these prior art
problems and shortcomings by providing a portable bladder
apparatus which is comprised generally ~f a pair of bladder
shell halves which can be fitted together in a sealable
fashion about a portion of an existent pipeline ~such as an
elbow or like fitting) where leaks may occur. The bladder
provides a pair of shell sections, each section having sealing
mating surfaces which correspond to one another and join to-
gether in an encapsulating sealing fashion about the suspect
fittings. The bladder could be manufactured in a variety
of desired shapes so as to properly encapsulate the subject
fitting which is suspect for corrosion, mechanical deterior-
ation, or leaXage. In the preferred embodiment, a valve
apparatus or regulator is provided which "senses" the presence
of a leak and can through gas instrumentation for example,
thereafter close a valve for example, thus shutting off the
"
flow of fluid through the pipeline and avoiding continued
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leakage and in the case of dangerous, volatile or hazardous
materials, a possible catastrophe~
In one aspect of the present invention, there is
provided an apparatus for detecting leaks in suspect piping
fittings comprising. a. a removable enclosure for encapsulating
a suspect piping fitting where leakage may occur' b. the
enclosure forming a space adjacent the fitting for collecting
leaking fluid from the fitting within the enclosure, c. fluid
responsive relay means connected with the space for transmitting
a signal generated in response to a pressure increase within
the enclosure caused by the leaking fluid; and d. means for
translating the signal into a responsive operation.
In a further aspect of the present invention,
there is provided a method of detecting leaks in suspect piping
system fittings, the steps comprising: aO identifying a fitting
which is suspect of eventual leakage, b- encapsulating the
suspect fitting with an enclosure to collect the leak, the
enclosure forming a defined space adjacent the fitting; c.
collecting leaking fluid within the enclosure; d. generating
a signal in response to a pressure increase in the space caused
by fluid leaking from the fitting, and e. transmitting the
; sign~al to a means for translating the signal into a responsive
operation.
In a still further aspect of the present invention,
there is provided an apparatus for detecting leaks in suspect
piping system fittings, comprising: a. non-rigid bladder means
for sealably encapsulating a suspect fitting portion of a pip-
ing system where leaks may occur, b. means for sealably attach-
ing the non~riyid bladder means to the suspect fittings, and
c. valve closure means responsive to the occurrence of a leak
in the suspect fitting and collected by the bladder means for
halting the flow of fluid within the piping system to which the
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bladder means is attached,
In a still further aspect of the present invention,
there is provided an apparatus for detecting leaks in suspect
piping fittings comprising: a. enclosure :means for sealably
encapsulating a suspect piping fitting where leaks may occur
b. clamp means attachable about the enclosure means for
sealably attaching the enclosure means to a suspect piping
fitting, leaks occurring in the piping fitting being at least
initially collected within the enclosure means; c- regulator
means connected with the enclosure means for transmitting a
signal generated in response to a pressure increase within the
enclosure means caused by the accumulation of a leak within
the enclosure means, d. conduit means for transmitting leaks
collected by the enclosure means to the regulator means, e-
valve means for controlling flow within the piping system to
; . which the enclosure means is attached, the valve means being
operated at least in part by the signal of the means from a
first "open flow" position to a second "closed flow" position,
the transmittal of a leak occurring in the suspect piping
fitting through the conduit means and to the regulator means
causing the regulator means to operate the valve means from the
first "open flow" position to the second "closed flow" position
halting flow in the piping system.
~ In a still further aspect of the present invention,
; there is provided a leak detection and shutoff apparatus for oil
and gas wells comprising: a. oil and gas well wing valve means
: for controlling flow of oil and gas at least in part from the
oil and gas well, b. enclosure means for sealably encapsulating
a suspect fitting portion of an oil and gas well, c. attachment
means for sealably attaching the enclosure means to the suspect
fitting, gas leaks occurring in the suspect fitting heing
collected within the enclosure means, and d. instrumentation
means connecting the enclosure means and the wing valve means
of the oil and gas well for closing the wing valve means, the
instrumentation means closing the wing valve means responsive
to the occurrence of a leak in the suspect fitting, the leak
collected by the enclosure means.
In a still further aspect of the present invention,
there is provided a leak detection and shutoff apparatus for oil
and gas wells comprising: a. bladder means for encapsulating
a suspect fitting portion of an oil or gas well where leaks may
occur, b. attachment means for sealably affixing the bladder
means to the suspect fitting, the bladder means then collecting
leaks occurring within the suspect fitting, c. valve means on
the oil or gas well for controlling the flow of oil and gas from
the oil or gas well, the valve means being operable from a first
"open flow" position to a second "closed flow" position, d.
regulator means connected with the bladder means for operating
the valve means from the "open flow" position to the "closed
flow" position; e. conduit means for transmitting leaks collected
within the bladder means to the regulator means, f. instrumenta-
: tion line connecting the valve means and the regulator means,
the accumulation of a leak in the suspect fitting by the bladder
: means and transmitted to the regulator means through the conduit
means effecting in the regulator means an operation of the valve
means from the first "open flow" position to the second "closed
flow" position.
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Brief Description of the Drawings
For a further understanding of the nature and objects
of the present invention, reference should be had to the
following detailed description taken in conjunction with the
accompanying drawings in which like parts are given like re-
ference numerals. Thus, the invention is illustrated by way of
example in the accompanying drawings wherein~
Figure 1 is a schematic view of a typical oil and
gas well illustrating the master valve and pipe assembly at
the top portion of the well,
Figure 2 is a schematic diagram of the preferred
embodiment of the apparatus of the present invention, and
Figure 3 is a schematic diagram of an alternative
embodiment of the apparatus of the present invention,
lS Figure 4 is a sectional view of a typical choke jacket
with the preferred embodiment of the apparatus of the present
invention attached thereto in a sealable fashion,
Figure 4-A is a prospective exploded view of the
bladder portion of the preferred embodiment of the apparatus
of the present invention illustrating the pipe clamps for hold-
ing the bladder to the suspect fitting in a sealable fashion
Figure 5 is a sectional view taken along lines 5.5
of Figure 4-A.
; Figure 6 is an oblique view of an additional em-
bodiment of the apparatus of the present invention.
--5--
`7
Detailed Description of the Preferred Embodiment
Figure 1 illustrates a typical piping system with
which -the present invention has application, the system being a
conventional oil and gas well showing a Christmas tree 20
mounted on the oil and gas well 22 itselE. As can best be seen
from Figure 1, oil and gas enters the bottom portion of the well
; through screen pipe 23 and moves upwardly through tubing 24 to
Christmas tree 20. Christmas tree 20 is attached at casing
assembly 25 with for example, a flanged connection. As can best
be seen from Figure 1, the gas flows upwardly (see arrows~
through Christmas tree 20 and passes laterally through manumatic
valves 26 and then through choke jackets 28. Often a certain
amount of sand or like abraslve material is combined with the oil
and gas, creating a mechanically erosive effect akin to sand-
blasting on the inside of Christmas tree 20 and more particularly
within the fittings, such as choke jacket 28. Cho]ce jacket 28
is thus "suspect" in that the mechanically erosive ef~ect of flow
can eventually cause minute leaks which continuously grow until
failure of the fitting or choke jaGket occurs with the escape of
volatile and polluting oil/gas presenting a hazard to property,
lives and the environment.
Figure 1 illustrates the portion of the oil and gas well
to which the present invention could be directed in an exemplary
installation, (i.e., the Christmas treej- It should be understood
that the present invention could be applied to any piping situa-
tion where a particular fitting or section of pipe is subject to
corrosion or failure and subsequent leaks. Thus, the present
invention would be particularly useEul in hazardous industrles
where even minute leaks would be either harmEul~ wasteful or
even disastrous to property, lives, and the environment.
~ le Christmas tree 20 shc~n in Figure 1 is provided
with manumatic valves 26 which control the flow of natural gas
from the well 22 to transmission pipelines. As can be seen by
-- 6 --
the arrows in Figures 1, 2 and 3, the gas flows upwardly and then
laterally through valves 26 to choke jackets 28. Choke jackets
28 often experience high turbulence and corresponding mechanical
erosion and therefore can be a potential source of leaks,
Figures 2 and 3 illustrate schematic piping diagrams of the
preferred and alternative embodiments of the apparatus of the
present invention illustrating their connection with the manumatic
valves 26 and choke jacket 28.
Figure 2 provides the preferred embodiment of the
apparatus of the present invention where a rupture of bladder 12
occurs often, a leak from choke jacket 28 is collected within
bladder 12. In Fiyure 2 can be seen manumatic valve 26 which is
held in an open position by means of a supply of instrumentation
control fluid flowing through conduit 16. Conduit 16 passes
through controller 14 which can be a cRBsM type controller as
; manufactured by U.S.I. Controller 14 is held in a posture which
: allows high pressure fluid 16 to pass therethrough in order to
maintain valve 26 in an open position as long as regulator 14
additionally receives low pressure control fluid through supply
line 10. Interruption of instrumentation control fluid to
controller 14 causes the controller to "shift" and interrupt the
supply of instrumentation control fluid to valve 26. Since
valve 26 requires a supply of control fluid to operate, it can
be seen that an interruption in the supply of instrumentation
: control fluid in conduit 16 causes the valve 26 to close, halting
-the flcw of fluids such as natural gas therethrough. As can be
seen best in Figure 2, supply conduit 10 feeds control fluid
to bladder 12 and thereafter to regulator 1~. It can he seen
that a rupture of bladder 12 (as will occur when a leak from
choke jacket 2~ fills bladder 12) will interrupt the f].ow of
instrumentation control fluid to regulator 1~.
~ ;D~ ~
In Fig~res 2 and 3, bladder 12 is shown encasing choke
jacket 28, but it can be used on any suspect piping fitting where
erosion could produce the occurrence of leaks from the fittings
at any time without notice.
Bladder 12, as will be discussed more fully herein-
after is attached to a suspect fitting such as a choke jacket
28 by means of, for example, a plurality of pipe clamps 30.
The bladder would be generally open at one end portion as is
illustrated in Figure 4-A, so that it could slip over the choke
jacket. The slitted portion designated generally by the numeral
40 in Figure 4-A would be sealed by gluing or like closure while
the openings 42-44 would be sealed by means of clamps 30, as is
illustrated in Figure 4-A~ Thus, a sealable encapsulating bladder
12 would be provided about any suspect fitting, with the end
result that a leak occurring from the fitting 28 would be
; collected by the bladder and thereafter transmitted through a
suitable conduit 45 to shut off apparatus or like indicating
structure, as will be discussed mo~e fully hereinafter, and as
was illustrated heretofore in Figures 2 and 3. Note that an
air space 13 can be provided be-tween bladder 12 and fitting 28
into which air space leaks from fitting 28 will flow and thus
be collected. Air space 13, likewise, provides a space into
which instrumentation air can flow through conduits 10 enroute
to controller 1~, as was described more fully above.
Figure 3 illustrates an alternative embodiment of the
'apparatus of the present invention which shows a typical manumatic
control valve 26 controlling the flow of oil and gas from line
27 which leaves Christmas tree 20 (note Figure 3)~ An instru-
mentation gas supply fed through conduit 16 and towards valve
26 maintains valve 26 in an "open" position. Regulator lS
can be for ex~mple, a Fisher Model 164~A regulator set at
approximately five to ten pounds in an exemplary insta:Llation-
-- 8 --
~ uch a regulator as the Fisher Model 164-A is a three
way pneumatic switching valve. It is spring loaded and diaphragm
actuated. A control connection to the regulator applies
sufficient pressure to the diaphragm causing a valve plug within
to shift and change the route o~ fluids flo~ing through the
regulator.
Utilizing regulator 15, a normally open port within
regulator 15 allows the control fluid supply to pass through
conduit 16 and maintain valve 26 in an "open" position~ If it
is undesixable to maintain a pressure on bladder 12, as is done
in the preferred embodiment, the alternative embodiment provides
no pressure on bladder 12, but rather bleeds pressure through
line 13 in the event of a leak within fitting 28. It can be
seen that the leak from fitting 28 will be caught within bladder
12 and flow through conduit 13, causing a build up of pressure
within both bladder 12 and line 13 and shifting a piston or like
valving member within regulator 15 to close the control fluid
supply in conduit 16. The lack of this control fluid to valve 26
causes it to close (as is known in the art).
me e~m~odiments of the present invention above dis-
closed provide a simple solution for the problem of early
detection of leaks in suspect fittings of flow lines, for example,
i as in the choke jacket of a Christmas tree portion of a natural
gas well.
As with the embodiment shown in Figure 2 ? bladder 12
~ould be attached in an encapsulating fashion about the suspect
fitting, such as a choke jacket 28 by using clamps 30, as is
illustrated in Figure 3. Clamps 30 can be for example, generally
"U" shape pipe clamps as is illustrated more particularly in
Figure 4 and 4-A.
Figures 4, 4-A and S illustrate more parti.cularly,
the structure of bladder .12. Bladder 12 is in the preferred
embodiment comprised of a generally flexible material such as,
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rubber, plastic film, or the like
.Such a pliable structure could easily be formed
around a suspect fitting as is illustrated in Figure 4 with a
typical oil field choke jacket 28.
The sealing of bladder 12 about suspect fitting 28
would be accomplished, for exarnple, by using a plurality of
pipe clamps 30, as is illustrated in Eigures 4 and 4-A, each
clamp 30 could be for example, comprised of a pair of generally
"U" shaped clamp halves 30, 32, with each clamp half providing
outwardly depending tabs 34 with openings 35 therethrough.
Clamp halves 31, 32 could be assembled by using a bolted
connection 40 as illustrated best in Figure 4-A.
In Figure 4-A, a bladder 12 is provided which is shaped
to generally fit over and encapsulate an oil field choke jacket
28. ~ote that a pair of slits 40, 46 are provided which will
allow bladder 12 to be split partially into a pair of bladder
halves 12-A and 12-s. Bladder halves 12-A and 12-B would be
separated by hand and the entire bladder structure 12 pulled over
the suspect fitting such as, choke jacket 28 and thereafter
sealed using pipe clamps 30 as aforementioned. Slits 40 and ~6
could be sealed by using glue or like suitable means. A rubber
cement or rubber glue could be used to seal slits 46 and 40, if
desirable.
The entire bladder structure 12 could be totally split
into two separate halves which are not connected at all if
desirable. In such an instance, each half would be mounted to
the pipe suspect fitting and thereafter, glued along the slits
40 and 46 with the sealable connection to fittlng 28 being
completed using pipe clamps 30.
In Figures 4 and 5, there is seen a conduit 10
which is integrally attached to bladder 12. Each conduit line
10 is schematically illustrated in Figure 2 and 3 and provides
-- 10 --
a conduit which instrumentation gas (Figure 2) or a collected
lea~ (Figure 3) could pass to perform the desired indication
and shut off function.
It will be understood by one skilled in the art
that the bladder structure 12 thus, taught by the present
invention is totally portable and could easily be attached
- to any existing piping system while the ~iping system is in
operation. Thus, the present invention provides a leak detection
and shut off apparatus which would easily be added to existing
gas wells, oil wells, or like piping systems where fittings are
suspect and where leaks might occur with the result being
possibly a loss of life or like catas-trophe.
In Figure 5, conduit 10 could connect to a section of
conventional tubing 50 with the connection being perfected in a
sealable fashion using clamps 30 and a bolted 48 connection.
;The apparatus of the present invention is totally
portable and capable of operating without the intervention of
a human operator, and can thus avert the possibility of any
hazards caused by leakage, whioh can eventually lead to
explosion, fire, or like -threats to property, life, and the
environment.
The present invention would allow a flow line control
valve to be shut off, and stop the flow of gas from a gas well
and thus avert the escape of gas through any minute leak which
might occur in a suspect fitting which leak over a period of
time in a remote area could grow with the continued escape of
natural gas or like volatile fluid posing a hazard to both
individuals and the environment. Such an early leak detec-tion
and valve closure system would save the unnecessary and wasteful
loss of much fuel before the lea~ is detected, even in the
case where a disaster does not occur~
Using the alternative embodiment, line 13 leaving
bladder 12 (see Figure 3) provides an instrumentation line
which would operate any pressure or volume change responsive
alarm, pressure guage or like indicator. Thus, as a leak in a
suspect fittin~ cccurred, the fluid would be trapped in bladder
12 and either pressure or volume or both would be transmitted
to line 13 for operation of the desired indicator - the leak
being detected.
Figure 6 best illustrates an additional embodiment
of the apparatus of the present invention generally designated
by Number 110. In Figure 6, there can be seen a typical pipe-
line 111 which is comprised of a plurality of piping joints
llla through llld adjoined at their end portion by attachments
such as bolting or welding to a conventional type cross-fitting
112. This embodiment of the leak detection apparatus of the
invention designated by the Numeral 110 is comprised in Figure 6
of a first casing half ~3 and a second casing half 114. Each
casing half 113 and 114 would provide a generally curved casing
wall 115 having a thickness as needed to accommodate pressures
within as will be discussed more fully hereinafter. The casing
halves 113 and 114 further provided with flanges 116 as is
illustrated in Figure 6. Opening 118 is provided in each flange
116, which openings will accommodate bolt 120 and nut 121 as
shown in Figure 6, thereby completing a seal.
In Figure 6 it can be further seen a sealing disc 130
which occupies an opening 124 when halves 113 and 114 are
assembled. Sealing disc 130 is of a pliable material, such as
rubber, for sealing between pipe 111 and opening 124 when
valve 113 and 114 are bolted together. In the preferred embodi-
ment sealing disc 130 is adapted with slit 125 so that it may befitted around the length of the pipe 111, and fitted in place.
A rubber base adhesive sealant can be applied between the exterior
circumference 127 of aisc 130 to more effectively seal the joints.
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Disc 130 also provides for annular shoulder 129 which acts as
a peripheral sealing connecting surface when the apparatus 110
- is assembled would insert into groove 111 of apparatus 110,
further establishing the seal therebetween. A regulator 140,
such as a typical regulator valve, will be discussed more fully
- hereinafter, is adapted to apparatus 110 at point 112. m e
regulator 140 will sense the presence of a leak ~rom thé fitting
housed within leak detection apparatus 110 and use the leak to
perform a desired instrumentation function, such as shutting off
the valve.
~ he encapsulating casing halves 113 and 114 a~ shown
can be sealably attached to about any itting such as a cross-
joint, for example, which is suspect or subject to leakage as
often the case where pipelines carrying corrosive or mechanically
abrasive material makiny turns through fittings or otherwise
i creating turbulance within the fitting that can cause a leak.
It is, however, with the rigid encapsulating leak
detection apparatus 110 to trap leaks from the suspect fitting
; within the assembly casing halves 113 and 114~
A suitable regulator or control valve 140 can be
attached to apparatus 110 in a sealable fashion at point 112.
After the sealable attachment of casing halves 113 and 114 with
the suspect fitting is accomplished, leaks occurring from the
fitting can then be collected within the rigid casing 110 and
there accumulation producing an increase in pressure and increase
in volume which could then activate the regulator or control
valve 1~0. It should be understood by one skilled in the art
that the present invention can be used in a plurality of fittings
as are known in the pipeline and the oil and gas art. For
30 example, the present invention can be used with L-bolts, T's~
valves, crosses and like fittings. The present invention provides
a leak detection apparatus which provides a rigid bladder
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casing 110 which can be reasonably fixed about any fitting
within a conventional pipe system, which fittings it is
subject to be damaged by mechanical or chemical erosion and
subsequent leakaye.
`; In the preferred embodiment of the apparatus of the
present invention 110, ring disc 130 would be inserted into
the space between pipeline sections llla through llld and
openings 124 to form a sealable connection between pipeline
- sections llla -through llld and rigid bladder casing 11OA
The detailed construction of bladder casing in its
bladder halves 113 and 114 is best seen by viewing Figure 6.
As before mentioned~ rigid bladder casing 110 is comprised of
a pair of casing halves 113 and 114. Each casing half 113
and 114 is comprised of a eurved bladder casing wall 115
having in the preferred embodiment ~our sets of arcuate side
ribs 117 which form openings 124 when casing halves 113 and
114 are assembled eorresponding upper and lower side ribs 117
registering and abutting to forrn the desired circular openings
124.
Each casing half 113 and 114 is further comprised of
a plurality of sealing flanges 116 which are generally
rectangular and flat, and provide a means for assembling casing
halves 113 and 114 together in a sealable fashion about a
suspect fitting where corrosion and leakage may appear. Each
flange 116 provides an inner sealing surface 128 as can be seen
in Figure 6. Further provlded on each sealing flange or openings
-- 118 through which connectors such as bolts 120 can be passed so
that a sealed bolted connection, for example, can be provided
using bolts 1~0 and nuts 121. It should be understood that other
suitable means of clamping, adhesion materials, welding ? gluing
or the like could be used to complete a sealab:Le connection of
casing halves 113 and 114 together. In Figure 6 in the preferred
ernbodiment, a bolt 120 ~ld nut 121 is shown as a connection ~or
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i7
allowing removal of the entire leak detection apparatus 110
as desired with minimal time and labor involved.
