DRAIN ASSEMBLY FOR A TANK OR CONTAINMENT VESSEL

ENSEMBLE VIDANGE POUR RESERVOIR OU ENCEINTE DE CONFINEMENT

English Abstract

A drain assembly for a tank or containment vessel of the type having a flexible and removable interior liner. The drain assembly comprises a drain intake in fluid communication with a wall traversing portion. The drain intake is operatively deployable in proximity to the bottom of the tank and the wall traversing portion is operatively deployable through a wall of the tank. The wall traversing portion includes a conduit portion in fluid communication with the drain intake and with a location exterior to the tank. The conduit portion includes an interior stopper plate and a threaded portion. The drain assembly includes a hammer nut threadably receivable over the threaded portion when the conduit portion is received through the wall of the tank such that tightening the hammer nut upon the threaded portion causes the hammer nut to engage the exterior of the tank wall causing the stopper plate to compress the tank liner against the interior surface of the tank wall thereby securing the drain assembly to the tank wall and helping to prevent the unintentional leakage of the contents of the tank through the tank wall.

French Abstract

Un ensemble vidange pour réservoir ou enceinte de confinement du type ayant une chemise intérieure amovible et souple. Lensemble vidange comprend une entrée de vidange en communication fluidique avec une partie transparoi. Lentrée de vidange peut être déployée de manière fonctionnelle à proximité du fond du réservoir et la partie transparoi peut être déployée de manière fonctionnelle à travers une paroi du réservoir. La partie transparoi comprend une partie conduit en communication fluidique avec lentrée de vidange et un emplacement à lextérieur du réservoir. La partie conduit comprend une plaque de butée intérieure et une partie filetée. Lensemble vidange comprend un écrou à tête rectangulaire reçu par vissage sur la partie filetée lorsque la partie conduit est reçue à travers la paroi du réservoir de manière que le serrage de lécrou à tête rectangulaire sur la partie filetée fait en sorte que lécrou se met en prise sur lextérieur de la paroi du réservoir. La plaque de butée comprime alors la chemise du réservoir contre la surface intérieure de la paroi du réservoir, ce qui permet de fixer lensemble de vidange à la paroi du réservoir et daider à prévenir la fuite accidentelle du contenu du réservoir à travers la paroi du réservoir.

Claims

CLAIMS
We CLAIM:
1.
A drain assembly for a tank or containment vessel of the type having a
flexible and removable interior liner, the drain assembly comprising:
a drain intake in fluid communication with a wall traversing portion, said
drain intake operatively deployable in proximity to the bottom of the tank
and said wall traversing portion operatively deployable through a wall of the
tank, said wall traversing portion including a conduit portion in fluid
communication with said drain intake and with a location exterior to the tank,
said conduit portion including an interior stopper plate and a threaded
portion, said drain assembly including a hammer nut, said hammer nut
threadably receivable over said threaded portion when said conduit portion is
received through the wall of the tank wherein tightening said hammer nut
upon said threaded portion causes said hammer nut to engage the exterior of
the tank wall causing said stopper plate to compress the tank liner against
the interior surface of the tank wall thereby securing said drain assembly to
the tank wall and helping to prevent the unintentional leakage of the
contents of the tank through the tank wall; and
an interior plate, an exterior plate and a spacer, each of said plates and
said
spacer receivable about said conduit portion with said spacer positioned
between said plates and said interior plate bearing against a first end of
said
spacer and said exterior plate bearing against a second end of said spacer,
said interior and exterior plates positioned such that when said hammer nut

is tightened upon said threaded portion said hammer nut engages said
exterior plate, which engages said spacer, which engages said interior plate,
causing said stopper plate to compress the tank liner between the stopper
plate and the interior plate.
2. The drain assembly as claimed in claim 1 including a gasket positioned
between said stopper plate and the tank liner, wherein tightening said
hammer nut upon said threaded portion causes said stopper plate to
compress said gasket against the tank liner.
3. The drain assembly as claimed in claim 1 wherein said stopper plate is
continuous about the perimeter of said conduit portion and rigidly fixed
thereto.
4. The drain assembly as claimed in claim 3 wherein said conduit portion
includes a 90 degree elbow permitting said conduit portion to be received
approximately perpendicularly through the tank wall and said drain intake to
be positioned in close proximity, and with its opening approximately parallel,
to the bottom of the tank.
5. The drain assembly as claimed in claim 4 wherein said threaded portion
comprises a sleeve that is threadably received upon said conduit portion, said
sleeve including exterior threads that permit the receipt of said hammer nut
thereon.
11

6. The drain assembly as claimed in claim 1 wherein said drain intake
includes a
drain pan recessed within the bottom of the tank.
7. A drain assembly for a tank or containment vessel of the type having a
flexible and removable interior liner, the drain assembly comprising:
a drain intake in fluid communication with a wall traversing portion, said
drain intake operatively deployable in proximity to the bottom of the tank
and said wall traversing portion operatively deployable through a wall of the
tank, said wall traversing portion including a conduit portion in fluid
communication with said drain intake and with a location exterior to the tank,
said conduit portion including a stopper plate and a threaded portion, said
drain assembly including a hammer nut, said hammer nut threadably
receivable over said threaded portion when said conduit portion is received
through the wall of the tank wherein tightening said hammer nut upon said
threaded portion causes said hammer nut to engage the exterior of the tank
wall causing said stopper plate to compress the tank liner against the
interior
surface of the tank wall thereby securing said drain assembly to the tank wall
and helping to prevent the unintentional leakage of the contents of the tank
through the tank wall, wherein said stopper plate is continuous about the
perimeter of said conduit portion and rigidly fixed thereto, and wherein said
conduit portion includes a 90 degree elbow permitting said conduit portion to
be received approximately perpendicularly through the tank wall and said
drain intake to be positioned in close proximity, and with its opening
12

approximately parallel, to the bottom of the tank, and wherein said threaded
portion comprises a sleeve that is threadably received upon said conduit
portion, said sleeve including exterior threads that permit the receipt of
said
hammer nut thereon; and
an interior plate, an exterior plate and a spacer, each of said interior and
exterior plates and said spacer receivable about said conduit portion with
said spacer positioned between said interior and exterior plates and said
interior plate bearing against a first end of said spacer and said exterior
plate
bearing against a second end of said spacer, said interior and exterior plates
positioned such that when said hammer nut is tightened upon said threaded
portion said hammer nut engages said exterior plate, which engages said
spacer, which engages said interior plate, causing said stopper plate to
compress the tank liner between the stopper plate and the interior plate.
8. The drain assembly as claimed in claim 7 including a gasket positioned
between said stopper plate and the tank liner, wherein tightening said
hammer nut upon said threaded portion causes said stopper plate to
compress said gasket against the tank liner.
9. The drain assembly as claimed in claim 7 wherein said drain intake
includes a
drain pan recessed within the bottom of the tank.
13

Description

CA 02825232 2013-08-27
TITLE
Drain Assembly For A Tank or Containment Vessel
FIELD
This invention relates generally to a drain assembly for use in a tank or
containment vessel.
BACKGROUND
Portable, semi-permanent or permanent containment tanks, enclosures or vessels
are commonly used in the oil and gas industry, in the mining and mineral
processing industries, and for a wide variety of other industries and
industrial
applications. Such tanks or enclosures are often used to store liquids,
slurries or
other fluids until such time as they can be further processed or otherwise
disposed
of or collected and shipped to other locations. An example of a temporary
containment vessel is one used in association with oil and gas drilling. When
drilling an oil or gas well, drilling mud is typically pumped down the well in
order to
serve as the source of energy to turn the drill bit. Drilling mud typically
contains
toxic and/or expensive additives that cannot be released into the environment,
or
that for economic reasons need to be recovered. In such instances as the mud
leaves the casing it is directed to a tank or containment vessel, after which
it can
be recycled back into the drilling circuit or gathered and shipped for
processing,
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CA 02825232 2013-08-27
disposal or reuse. A further example of the use of such tanks in the oil and
gas
industry is to contain large volumes of fluids during fracking operations.
Since in many instances containment tanks or vessels are required on a
temporary
or semi-permanent basis, they are often formed in a manner that allows them to
be
transported to the desired location, assembled, used for the desired purpose,
disassembled, and then shipped for subsequent use in a different location. To
assist in quick assembly and disassembly, the tanks may be formed from a
series of
individual panels that create the tank's bottom and walls. After the panels
have
been erected, a liner is typically inserted in order to provide a fluid-tight
containment.
In order to drain the contents of the tank, a suction line from a pump can be
lowered over one of the tank walls. However, in cold weather applications
where
the top of the tank is covered in order to prevent freezing of the fluids,
deployment
of a suction line over a tank wall becomes somewhat more difficult. Further,
the
pumping equipment used to drain large tanks can be of considerable size and
weight, making it sometimes necessary to utilize cranes or other lifting
apparatuses
in order to lower the suction line into the tank. For that reason, others have
proposed installing a drain port within the side wall of the tank. Such ports
require
the use of a series of bolts, that extend through the tank wall and that
secure the
drain port within the wall to permit the tank to be drained when desired,
while at
the same time allowing the drain to be sealed to prevent unintentional leakage
of
the tank contents. Unfortunately, in the case of large tanks that are lined
with a
flexible liner, it has been found that the pumping of material into and out of
the
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CA 02825232 2013-08-27
tank often causes small shifts in the liner. In such cases shifting of the
liner puts
considerable stress upon the liner material at the locations where the bolts
that
extend through the tank wall to maintain the drain in place pass through the
liner
material. The stress upon a liner can cause tearing and shifting of the liner,
which
in some instances can result in a leakage of the tank contents. Further, the
assembly of the drain within the tank is laborious as it typically requires an
individual both inside and outside the tank in order to assemble the bolts.
Where
the tank is to be disassembled, removal of the drain will often require an
individual
to enter the tank, which may present health hazards depending upon the
materials
that have been stored therein.
SUMMARY
The invention therefore provides a drain assembly for a tank or containment
vessel
of the type having a flexible and removable interior liner, the drain assembly
comprising a drain intake in fluid communication with a wall traversing
portion, said
drain intake operatively deployable in proximity to the bottom of the tank and
said
wall traversing portion operatively deployable through a wall of the tank,
said wall
traversing portion including a conduit portion in fluid communication with
said drain
intake and with a location exterior to the tank, said conduit portion
including an
interior stopper plate and a threaded portion, said drain assembly including a
hammer nut, said hammer nut threadably receivable over said threaded portion
when said conduit portion is received through the wall of the tank wherein
tightening said hammer nut upon said threaded portion causes said hammer nut
to
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CA 02825232 2013-08-27
engage the exterior of the tank wall causing said stopper plate to compress
the
tank liner against the interior surface of the tank wall thereby securing said
drain
assembly to the tank wall and helping to prevent the unintentional leakage of
the
contents of the tank through the tank wall
Further aspects of the invention will become apparent from the following
description
taken together with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
For a better understanding of the present invention, and to show more clearly
how
it may be carried into effect, reference will now be made, by way of example,
to the
accompanying drawings which show exemplary embodiments of the present
invention in which:
Figure 1 is an upper side elevational view of an embodiment of a portable tank
or
containment vessel.
Figure 2 is a side elevational view through a wall and the bottom of tank or
containment vessel incorporating therein a drain assembly in accordance with
an
embodiment of the present invention.
Figure 3 is a left hand side elevational view of the drain assembly shown in
Figure
2.
Figure 4 is a partially exploded view of an embodiment of the drain assembly.
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CA 02825232 2013-08-27
DESCRIPTION
The present invention may be embodied in a number of different forms. The
specification and drawings that follow describe and disclose some of the
specific
forms of the invention.
With reference to the attached Figures there is shown in Figure 1 an
embodiment of
a portable tank or containment vessel 1 comprised generally of walls 2 and a
floor
3. In the particular embodiment shown in Figure 1 the flexible liner that
would
commonly be placed within the walls of the tank is not shown. Such tanks are
often rectangular in shape, however, they may also take any one of a very wide
variety of other geometric shapes depending upon available space and intended
use.
Figures 2 through 4 show an embodiment of a drain assembly 4 in accordance
with
the present invention. In general, the drain assembly 4 is comprised of a
drain
intake 5 that is connected to and in fluid communication with a wall
traversing
portion 6. As shown, drain intake 5 is positioned, and deployable when in use,
in
close proximity to the bottom or floor 3 of the tank with the wall traversing
portion
6 deployable through tank wall 2. The wall traversing portion 6 includes a
conduit
portion 7 that fluidly communicates between the drain intake 5 and a location
exterior to the tank walls. Typically, conduit portion 7 would be in the form
of a
heavy walled pipe that includes a 90 degree elbow 8, permitting the conduit
portion

CA 02825232 2013-08-27
to be received approximately perpendicularly to the tank wall with the drain
intake
positioned in close proximity, and with its opening approximately parallel to,
the
bottom or floor of the tank.
In accordance with an aspect of the invention, conduit portion 7 includes an
interior
stopper plate 9 and a threaded portion 10. The drain assembly further includes
a
hammer nut 11 having interior threads such that the hammer nut may be
threadably receivable over threaded portion 10. Preferably, threaded portion
10 of
conduit portion 7 is located at the end of the conduit, opposite to elbow 8
and at a
point where the end of the conduit exits the tank's wall into the exterior
environment. In one embodiment of the invention threaded portion 10 comprises
a
sleeve 12 that is itself internally threaded and received upon threads 13 of
the end
of conduit portion 7. In that instance the exterior of sleeve 12 will be
threaded to
match the interior threads of hammer nut 11, permitting the hammer nut to be
threadably received about the exterior of the sleeve.
With reference to Figure 2, stopper plate 9 is fixed to conduit portion 7 at a
location
that allows the outer end of the conduit portion to extend through the tank's
wall
when the stopper plate comes into contact with, or is in close proximity to,
the
interior surface of the wall. It is expected that in most instances the
stopper plate
will be continuous about the perimeter of the conduit and rigidly fixed
thereto. It
will thus be appreciated that with the outer end of conduit portion 7
extending
through a hole or opening in the tank wall, hammer nut 11 can be threadably
received over with the end of the conduit portion (or the end of sleeve 12
where
sleeve 12 is utilized) such that tightening the hammer nut causes the nut to
engage
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CA 02825232 2013-08-27
,
the exterior wall of the tank, thereby causing stopper plate 9 to compress the
tank
liner 14 against the interior surface of the wall. As the hammer nut is
further
tightened the drain assembly will be rigidly secured to the tank's wall and
the
compressive force applied by the stopper plate compressing the liner against
the
tank wall will help to prevent the unintentional leakage of the contents of
the tank.
To further prevent leakage, a gasket 15 may be positioned between the stopper
plate and the tank liner.
In an embodiment of the invention, the drain assembly may further include an
interior plate 16, an exterior plate 17, and a spacer 18. Each of interior
plate 16,
exterior plate 17 and spacer 18 are receivable about conduit portion 7 with
the
spacer positioned between the interior and exterior plates such that the
interior
plate bears against one end of the spacer and the exterior plate bears against
a
second or opposite end of the spacer. In some applications it may be desirable
to
weld or otherwise secure the interior and exterior plates to the opposite ends
of the
spacer.
Setting-off the distance between interior plate 16 and exterior plate 17 (i.e.
determining the size of spacer 18) will enable the two spacer plates to be
positioned about conduit portion 7 such that they lie generally co-planar with
the
interior and exterior surfaces of the tank's wall. In this manner when the
hammer
nut is tightened upon the threaded portion of the conduit, or upon sleeve 12
(where
sleeve 12 is utilized) the hammer nut will largely engage exterior plate 17.
The
force of the hammer nut will thus cause the exterior plate to engage the
spacer,
cause the spacer to engage the interior plate, and cause the stopper plate to
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CA 02825232 2013-08-27
compress the tank liner between the stopper plate and the interior plate. In
this
manner, the force supplied by the hammer nut compressing the stopper plate
against the liner will be borne by interior plate 16, exterior plate 17 and
spacer 18,
thereby minimizing the compressive force applied to the tank wall. With the
hammer nut engaging exterior plate 17, the frictional force that would
otherwise
occur between the nut and the tank wall as the nut is rotated will be borne by
plate
17. The use of interior and exterior plates 16 and 17 (which will generally be
circular in nature) also helps to distribute torsional or twisting loading of
the drain
assembly across a greater portion of wall 2.
The drain assembly may include a drain pan 19 recessed within the bottom of
the
tank immediately adjacent to drain intake 5. Further, the drain intake may
have
incorporated into it a screen, grate or other similar apparatus to avoid
drawing
large size objects or debris into the drain assembly.
It will be appreciate that the above described structure provides a fast and
simplified method to securely retain a drain assembly within the wall of a
tank or
containment vessel, of the type that utilizes a flexible and removable
interior liner.
The structure permits the drain assembly to be held securely in place without
the
use of a series of bolts that must pass through the liner material, and
thereby
removes the difficulties that are often associated with traditional drains
wherein the
liner may be ripped or torn about the bolt holes should the liner shift during
loading
or unloading the tank. In addition, the unique plate, conduit and nut
structure
described permits the drain assembly to be secured to the wall quickly and
efficiently. Where the drain assembly utilizes interior plate 16, exterior
plate 17
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CA 02825232 2013-08-27
,
and spacer 18, there is further presented the ability to accommodate the
compressive and frictional force that would otherwise be exerted upon the
walls of
the tank, that could cause damage thereto.
It is to be understood that what has been described are the preferred
embodiments of the invention. The scope of the claims should not be limited by
the preferred embodiments set forth above, but should be given the broadest
interpretation consistent with the description as a whole.
9

Representative Drawing