BACKGROUND AND SUMMARY OF THE INVENTION
[0001] The present invention is a container for the transportation of bulk liquid materials.
More particularly, the present invention is a 55 gallon drum having an inner, disposable
liner which is heat sealed at an aperture in its upper end to a bung which in turn
may be secured to a fill opening in the top wall of the drum. When filled with a bulk
liquid material, the liner conforms in shape to the shape of the inner surfaces of
the tank and, upon being emptied, the liner collapses and is easily removed from the
drum through the fill opening.
[0002] The most desirable and convenient method of transporting various liquid materials
is in bulk quantities. While numerous containers may be used for such transportation,
the 55 gallon drum has gained widespread acceptance by commercial suppliers and industrial
consumers. A variety of materials, including such substances as solvents and grease,
are transported in these 55 gallon drums. Regardless of the material being transported,
if the drum is to be subsequently used for transporting a differing substance, the
inside of the drum must be cleaned prior to the subsequent use.
[0003] U.S. Patent No. 4,044,912, issued August 30, 1977, assigned to the Assignee of the
present application, discloses a container including a rigid outer tank having a collapsible
bag liner for retaining viscous substances such as grease. A vane shaped spacer is
disposed within the bag to provide a skeletal structure about which the bag can collapse
as the viscous substances are removed. The skeletal structure thereby ensures a more
complete evacuation of the viscous material contained in the tank.
[0004] It is an object of the present invention to provide a drum which may be used to transport
a bulk liquid material without having to be cleaned prior to such use.
[0005] It is also an object of the present invention to provide a drum having a disposable
liner for the transportation of bulk liquid materials.
[0006] It is another object of the present invention to provide a drum having a liner which
is secured to a bung which is in turn mounted in an opening formed in the top wall
of the drum.
[0007] It is an additional object of the the present invention to provide a drum which allows
for easy removal of the liner through an opening formed in the top wall of the drum.
[0008] The present invention provides for a 55 gallon drum which may be formed of a plastic
or metal and has two openings formed in its top wall. A plastic liner is disposed
within the drum and has formed therein two apertures which are substantially aligned
with the openings. At one aperture, a portion of the liner extending therearound is
heat sealed to an outer bung which is then threaded into the appropriate opening.
The body of the outer bung extends through the opening and has a threaded central
opening which provides access to the interior of the liner. As the liner is filled
with the materials to be transported, it conforms in shape to the shape of the inside
surface of the drum. An inner bung is then positioned in the threaded opening of the
outer bung to seal the drum. As the container is emptied, the liner collapses and
is readily removed from the drum through one of the openings formed in the top wall.
[0009] Thus, the present invention facilitates the removal of the transported materials,
the disposal of residue after discharge and the elimination of cleaning prior to reuse.
In that the liner may be disposed of through burial, incineration or recycling, no
large quantities of water are needed for cleaning purposes.
[0010] Additional benefits and advantages of the present invention will become apparent
to those skilled in the art to which this invention relates from the subsequent description
of the preferred embodiments and the appended claims, taken in conjunction with the
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Figure 1 is a plan view of a bulk liquid material transportation container incorporating
the principles of the present invention.
[0012] Figure 2 is a sectional view taken substantially along line 2-2 in Figure 1 illustrating
the position of the liner within the drum when filled with a bulk liquid material.
[0013] Figure 3 is an enlarged sectional view of a portion of Figure 2 detailing one embodiment
the liner and bung construction of the present invention.
[0014] Figure 4 is an enlarged sectional view of a portion of Figure 2 illustrating a second
embodiment of the liner and bung construction of the present invention.
DETAILED DESCRIPTION OF THE DRAWINGS
[0015] Now with reference to the drawing, Figure 1 illustrates a plan view of a container
10 embodying the principles of the present invention. An outer drum 12, in the shape
of a standard 55 gallon drum, is formed of metal, plastic or other material and includes
a base 14, upright side walls 16 and a top wall 18 which combine to define a central
cavity 19. Formed in the top wall 18 and rising thereabove are two ports or openings
20 and 22. In the event of an object falling on top of the container 10 or the container
10 being toppled onto its side, the top wall is further provided with a rim 24 designed
to prevent damage to the openings 20 and 22.
[0016] Disposed within the central cavity 19 of the drum 12 is a liner 26. The liner 26
is constructed of a thin plastic material having a thickness approximately three times
that of a common household garbage bag. Two apertures 28 and 30 are formed in the
top of the liner 26 and are substantially aligned with the openings 20 and 22 of the
drum 12.
[0017] While the container 10 is illustrated as having two openings 20 and 22, the present
invention could also be constructed with a single opening. However, a 55 gallon drum
provided with two openings is standard within the industry and permits all of the
normal operations required of the drum 12. The larger 20 of the two openings 20 and
22 is generally used for filling and emptying the container 10 while the smaller of
the openings 22 is typically used as a vent opening.
[0018] When the liner 26 of the present invention is to be incorporated into a drum 12 having
two openings 20 and 22, a portion 27 of the liner 26 defining one of the two apertures
28 and 30 is fixably secured to an outer bung 32. The outer bung 32 may be formed
of rigid plastic or similar material. In that the outer bung 32 is also formed of
plastic, this securement can be achieved by heat sealing or welding the liner 26 to
the outer bung 32.
[0019] Two embodiments of a bung structure constructed in accordance with the principles
of the present invention are disclosed. While both embodiments are simultaneously
shown in Figure 2, only one of the openings 20 or 22 will incorporate an embodiment
at a given time. The present invention may be incorporated into either of the two
openings 20 or 22, however, for the sake of clarity, only one opening 20 will be discussed
in the following description. Where appropriate, corresponding features of the embodiments
will be given like designations in Figures 3 and 4.
[0020] As seen in Figure 3, in the bung structure 31 of the first embodiment, the portion
27 of the liner 26 forming the larger aperture 28 is heat sealed to a lower portion
34 of the outer bung 32. The outer bung 32 includes a cylindrical body 40 which extends
downward through the opening 20 thereby constricting the opening 20. However, outer
bung 32 does not fully constrict the opening 20 in that a threaded portion 41 of the
cylindrical body 40 defines an access opening 39 to the interior of the liner 26.
Integrally formed with the cylindrical body 40 is an outwardly extending flange 36
which engages an upper portion 38 of the opening 20. The resting engagement of the
flange 36 with the upper surface 38 of the opening 20 thus supports and prevents the
outer bung 32 and attached liner 26 from passing through the opening 20 and into the
cavity 19 of the drum 12.
[0021] The liner 26 is installed in the drum 12 by inserting it through the opening 20.
When the liner 26 is fully inserted, the flange 36 of the outer bung 32 will engage
the upper surface 38 of the opening 20 and support the liner 26 hanging therebelow
in the central cavity 19. To align the second aperture 30 with the remaining opening
22, the liner 26, along with the outer bung 32, is rotated. The second aperture 30
may be secured to the drum 12 by various methods. One possible method is to draw the
portion defining the aperture 30 up through the second opening 22 and securing it
therearound by means of a threaded engagement with a cap or conventional bung.
[0022] For safe operation of the drum 12, the outer bung 32 of the first embodiment is secured
to the opening 20 formed in the top wall 18. In so doing, the present embodiment provides
an interiorly threaded closure cap 42 which engages the exterior threads of the opening
20. Upon full engagement, the flange 36 of the outer bung 32 is securely retained
between the upper surface 38 of the opening 20 and the cap 42.
[0023] The closure cap 42 is also provided with an central opening 44. The opening 44 permits
the contents of the container 10 to be accessed while the outer bung 32 is retained
securely in position. To seal the opening 20 for transportation of the drum 12, an
inner bung 46 is provided which engages the threaded portion 41 of the cylindrical
body 40.
[0024] As described above, when two openings 20 and 22 are incorporated into the top wall
18, filling of the container 10 is easily achieved by providing two points from which
the liner 26 may hang. The side walls 16 or top wall 18 of the drum 12 may be further
provided with vent openings (not shown) to allow air contained between the drum 12
and the liner 26 to evacuate during filling and expansion of the liner 26. To further
assist in the filing of the liner 26, the cap securing the second aperture 30 in position
may be provided with a vent opening which permits the evacuation of air from the liner
26 itself.
[0025] As previously mentioned, the container 10 can be constructed without a second opening
22. When constructed in this manner, the liner 26 may be provided with a tab (not
shown) designed to fit into a corresponding tab opening (not shown) and thereby secure
the liner 26 during filling of the container 10.
[0026] When being transported, both bung openings 20 and 22 of the container 10 may be completely
sealed or provided with a vent opening 48. One such vent opening 48 is illustrated
on the inner bung 46 of Figure 3 and another is further described below in the description
of the second embodiment.
[0027] The embodiment shown in Figure 4 illustrates a bung structure 50 where the cap, flange
and cylindrical body are integrally formed to produce an outer bung or bulkhead 52.
In the second embodiment, the portion 27 of the liner 26 forming the aperture 28 is
heat sealed to the outer surface of an inner cylindrical body 54 having an access
opening 55 with internal threads 56. The cylindrical body 54 is integrally formed
with an overhang structure 58 having internal threads 60. Prior to the engagement
of the threads 60 with those of the opening 20, the liner 26 must be oriented so that,
upon full engagement of the overhang structure 58 and the opening 20, the second aperture
30 will be in alignment with the second opening 22. Again, if it is desired that a
single opening be incorporated into the container 10, the liner 26 may be provided
with a tab (not shown) for securing the liner 26 during filling.
[0028] To enable sealing of the container 10, an inner bung 62 is provided which engages
the inner cylindrical body 54 and restricts the access opening 55. To provide for
venting, the inner bung 62 may be further provided with an interiorly threaded opening
64 capable of acceptance of a threaded vent means 66 to further restrict the opening
20. The vent means 66 is opened by rotating a vent plug 68 some amount until the container
10 vents through the engagement of the threaded opening 64 and the vent plug 68.
[0029] After delivery of the container 10 to an industrial consumer, the materials contained
therein may be extracted by removing the inner bung 46 (or 62) and engaging a suction
pump (not shown) with the outer bung 32 (or 52). Once the contents have been consumed
and the liner 26 is empty, the second aperture 30 may be released from the second
opening 22 and the outer bung 32 (or 52) disengaged from the first opening 20. The
liner 26 may then be removed through the first opening 20 and disposed of properly.
The insertion of a new liner 26 immediately enables the container 10 for reuse.
[0030] With a removable liner 26, the necessity of cleaning the interior of the drum 12
has been eliminated. By removing the liner 26 through an opening 20 in the top wall
18, the detailed procedure of removing the top wall 18 or lid of the drum 10 is also
eliminated. Additionally, the present invention also prevents a plastic drum 12 from
becoming permeated with the transported liquid materials or cleaning materials. The
final result is a drum 12 which experiences no down time for cleaning purposes.
1. A container for retaining bulk liquid materials comprising:
an outer tank having walls defining an enclosed cavity of a predetermined shape
and having at least one fill opening; and
a collapsible inner liner positioned within said cavity and being of a shape substantially
conforming to said predetermined shape, said liner further having a portion defining
an aperture and a first bung fixably secured thereto, said aperture and said first
bung being in alignment with said fill opening, said first bung being removably engaged
with said outer tank at said fill opening and having a central opening so as to partially
constrict said fill opening, a second bung having a body of a size corresponding to
said central opening and being removably engaged with said first bung at said central
opening therein to at least partially seal said container.
2. A container for retaining bulk liquid materials as set forth in Claim 1 wherein said
liner is thin walled and substantially fully collapsible enabling removal through
said fill opening upon disengagement of said first bung.
3. A container for retaining bulk liquid materials as set forth in Claim 1 wherein said
fill opening is further defined by a threaded cylindrical extension having an upper
surface.
4. A container for retaining bulk liquid materials as set forth in Claim 3 wherein said
first bung includes a body extending through said cylindrical extension and an integrally
formed flange in engagement with said upper surface, a closure cap having a portion
extending over said flange and being in engagement with said threads thereby securing
said First bung and defining an opening in substantially coaxial alignment with said
central opening.
5. A container for retaining bulk liquid materials as set forth in Claim 3 wherein said
first bung includes a body extending through said cylindrical extension and being
integrally formed with a fastening portion in engagement with said threads of said
extension.
6. A container for retaining bulk liquid materials as set forth in Claim 1 wherein said
second bung includes a vent means.