Note: Descriptions are shown in the official language in which they were submitted.
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SHIPPING CONTAINER AND METHOD OF CONSTRUCTION THEREOF
[0001] This application claims priority to U.S. Provisional Patent Application
No. 63/076,061
filed September 9, 2020, entitled "SHIPPING CONTAINER AND METHOD OF
CONSTRUCTION TIIEREOF," which is hereby incorporated by reference herein.
[0002] The present invention relates to reusable intermodal shipping
containers.
BACKGROUND OF THE INVENTION
[0003] Containers are used to transport materials. The containers may be
transported by trucks
on the highway, by trains on the railway and or by nautical vessels, for
example. They may be
individual or stacked on top of one another.
[0004] The basic design of intermodal containers has changed very little over
the past 25 years.
In fact, the performance of some current containers may have actually been
compromised to
achieve some of the (customer requested) design targets to such a point that
they very likely no
longer meet the required loading/stacking/handling requirements as mandated by
AAR M-930
(or similar/equivalent governing industry standards).
[0005] U.S. Publication No. 20070051719, U.S. Publication No. 20140069912 and
U.S.
Publication No. 20140144922, all teach commercial storage and transport
containers having a
roof, side wall, floor, and one or more support structures. However, many
problems still exist
with containers.
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[0006] The inventive design of the present invention greatly improves the
strength of the
container and also eliminates "chronic" issues that have not been addressed or
resolved over the
past 25 years. Additionally, some of the inventive attributes will also likely
increase the
anticipated service life of the container.
SUMMARY OF THE INVENTION
[0007] The present invention provides a reusable intermodal shipping container
for use on
highway, railway, and nautical transportation to contain, store, and protect
cargo during
transport. For highway use, it is coupled with a dedicated chassis that is
pulled by a tractor
(semi). For rail use, it is either set into the cavity within a well rail car,
set on a flatbed car, or it
is stacked on top of, and connected, to another intermodal container already
in these locations.
They can also sit on a chassis that is sitting on a flatbed car. In general,
the design permits all
intermodal containers to be stacked on top of and connected to other
intermodal containers.
[0008] The present invention provides a reusable intermodal shipping
container, containing
enhanced design features permitting greater interior cargo volume while having
a reduced overall
tare weight (container mass) and delivering superior performance and an
anticipated increase to
expected service life.
[0009] The present invention provides an intermodal shipping container
including one or more
intermediate gable posts (also known as staking or intermediate posts) and/ or
intermediate gable
headers adapted to increase an internal width and strength of the container,
wherein the gable
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posts and/ or the gable headers include twin channels having at least two
internal flanges welded
to a gable post plate and/ or gable header plate.
[0010] The present invention also provides an intermodal shipping container
including one or
more upper castings having an integral top rail ledge, also referred to as a
seat, wherein a top rail
of a side wall hangs on the integral top rail ledge.
[0011] The present invention also provides an intermodal shipping container
including "C"
shaped channel beam main frame cross members.
[0012] The present invention also provides an intermodal shipping container
including front and
rear bolsters including an integral seating and fastening surface and slots,
the integral seating and
fastening surface adapted to fasten and support flooring and the slots used
for welding, wherein
the bolster is flush with a top surface of flooring.
[0013] The present invention also provides an intermodal shipping container
including one or
more nested rear corner posts subassemblies, the one or more nested rear
corner posts having a
notch and protrusion connection, wherein a protrusion in a lower rear casting
engages with a
corresponding notch in the rear corner post.
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[0014] The present invention also provides an intermodal shipping container
including a one-
piece continuous top plate including an integral lip connecting the top plate
and a roof. The top
plate integral roof filler piece forms an integrated welding location for the
roof panels.
[0015] The present invention also provides a shipping container having a front
top plate with an
integral front roof filler piece which forms an integrated welding location
for the roof panels.
[0016] The present invention also provides rear headers with integral internal
gussets that further
enhance the strength of the header assemblies
[0017] The present invention also provides an intermodal shipping container
including one or
more rear lower castings, wherein the one or more rear lower castings are an
integral interlocking
interface, wherein a door sill abuts the rear lower casting and a rear corner
post, the one or more
rear lower castings having an observation hole to externally view a chassis
twist lock. The rear
lower casting profile increases the length of the weld interface and therefore
the strength
[0018] The present invention also provides a method of fabricating an
intermodal shipping
container, the method including preparing a sub assembly by welding a top rail
onto a side wall
panel, introducing the side wall sub assembly to intermediate gables from
above, and lowering
the wall sub assembly until the wall assembly is entirely supported by the
intermediate gables
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BRIEF DESCRIPTION OF THE DRAWINGS
[0019] Figure 1 shows a 53' Intermodal Shipping Container of the present
invention;
[0020] FIGS. 2A and 2B show a conventional gable post design;
[0021] FIGS. 2C, 2D, 2E and 2F show exemplary embodiments for a twin channel
gable design;
[0022] FIGS. 3A and 3B show a top rail ledge/seat of an interlocking feature
of the present
invention in the upper casting;
[0023] FIGS. 4A and 4B show main cross members of the present invention;
[0024] FIG. 5A shows a conventional rear header contact plate;
[0025] FIGS. 5B, 5C and 5D show the rear header contact plate of the present
invention;
[0026] FIG. 6 shows a rear header door assembly/weldment of the present
invention;
[0027] FIGS. 7A and 7B show an exemplary embodiment of the rear header and
bolster (or door
header and door sill) with integral gussets;
[0028] FIG.8A shows a conventional front header contact plate;
[0029] FIGS. 8B and 8C show a front header contact plate of the present
invention;
[0030] FIGS. 9A and 9B show a rear lower casting of the present invention;
[0031] FIG. 10A shows a conventional intermediate bolster;
[0032] FIG. 10B shows an intermediate bolster of the present invention;
[0033] FIGS. 11A and 11B show a rear corner post of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0034] The following terminology can be defined interchangeably: 40' gable (or
just "gable"),
intermediate stacking post, and stacking frame; Gable header, gable upper (or
top) channel and
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plate assembly, intermediate header and intermediate frame upper (or top)
member; Rear
intermediate bolster, rear 40' gable (or rear intermediate stacking
post/frame), lower (or
bottom) channel and plate assembly, and lower (or bottom) cross member; Upper
casting and
upper handling fitting; Lower rear casting, lower 53' rear casting, and lower
rear corner casting.
The same terminology is also applicable to all size shipping containers
including 60', for
example.
[0035] There are four bolsters in the floor of a container. The front bolster
is the lower structural
member of the front facing wall which engages with the front bolster of the
associated chassis.
The two, intermediate bolsters connect the lower, intermediate 40' castings,
respectively and
form the lower portions of the structural "ring" of the intermediate stacking
frames. Therefore,
there is both a front and rear intermediate bolster. And finally, the rear
bolster (sometimes
referred to as a "door sill") which rests directly upon the rear bolster of
the associated chassis.
[0036] Although described as highway and railway cargo carrying shipping
containers
throughout the specification, the present invention is not limited to such
use. Various aspects for
this invention can be used in other applications and/or industries.
[0037] FIG. 1 shows a shipping container of the present invention having roof
6, front wall/door
4 and side walls 8.
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[0038] FIGS. 2A and 2B show an existing gable post design including twin
external channels 23
and upper casting 21. Weld 27 is applied using industry best welding practices
on both sides of
channels 23, for example a groove weld. Weld 25 is also used and runs at the
top of touching
channels 23. Extensions 29 provide additional surface for wall panel welds.
[0039] FIGS. 2C, 2D, 2E and 2F show twin channel gable posts and gable header
designs of the
present invention. Twin channel designs may include channels that are
standard, mirrored,
symmetrical or other differing shapes. Twin channels 24 permit two additional
internal flanges,
which serve as internal gussets, to provide a significant increase to the
resistance to
bending/buckling when the container has additional containers stacked on top
of it in rail, yard,
or nautical applications. Twin abutted flanges of channels 24 significantly
increase the section
modulus. Twin abutted flanges are suitably welded (e.g., plug welded) to gable
post plate 22
through slots 26 creating a twin "boxed" design that is strong and stiff Twin
abutted flanges of
channels 24 significantly increase load paths L for stress transmission from
upper casting 20 to
the lower casting. Similarly, the lower 40' intermediate casting (not shown)
also has a
corresponding interlocking member, such as a protrusion that allows for
completely
interchangeable placement of the twin channels and easier production and
material handling.
The design of the present invention allows the interior width of the container
to be increased,
increasing the cargo carrying capacity of the container, while still meeting
the loading
requirements mandated by the AAR M-930 (or similar/equivalent governing
standards). The
design can also be used on containers having conventional interior widths
(less than 100-
1/2-).The twin channel design and abutted flanges is also extended to the
gable header plates 28
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as well which increases the strength of the top of the container permitting
the use of thinner and
lighter roof panels, such as 1.1mm, for example, further reducing tare weight
of the container
while still meeting the strength requirements mandated by the AAR M-930 (or
similar/
equivalent governing standards).
[0040] Current container interior widths are generally limited to 99". In a
conventional, high
cube 53-foot container, this limits interior volumetric payload capacity to
approximately 3950
cubic feet. The present invention can be used with any length container,
including in particular
60' lengths. In the 53' embodiment described herein, a container with an
internal width of 100-
1/2" is enabled. This will permit an increase of volumetric payload capacity
to approximately
4013 cubic feet (approximately a 1.5% increase) in a 53' length embodiment,
and more in larger
containers. To facilitate this width increase, an enhancement to the 40' gable
posts are used with
a twin channel design to provide the 100-1/2" wide container with equivalent
strength to the
conventional 99" wide container design. This makes this container more
efficient to operate.
[0041] In one exemplary embodiment of the present invention, the maximum
exterior width of
the container is 2600mm (102-3/8"). To achieve a 100-1/2" inside width, the
entire gable post
assembly depth can only be 15/16- each. Ultra-high strength steel, combined
with optimized
design and precisely controlled manufacturing geometry and welding techniques,
creates a
design that meets the stacking and loading requirements mandated by the AAR M-
930 (or
similar/equivalent governing standards).
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[0042] In another exemplary embodiment of the invention, a single "twin"
profile gable post
design is shown in FIGS. 2E and 2F. The same design profile also applies to
gable headers. The
single twin channel designs may include profiles have differing shapes then
shown that achieve
the same or superior strength. The profile may be symmetrical or asymmetrical.
Single twin
channels 204 are welded to gable post plate 22 with welds 27, such as fillet
welds, on both
exterior sides of twin channels 204. Twin channel gable post has integral
interior flanges located
where the two sloped pieces of single twin channels 204 meet at weld 25.
Single post channels
204 have a rolled or brake press profile and can be the same width W as two-
piece twin channels
24 of the present invention. The single twin channel design of the present
invention reduces the
susceptibility to crevice corrosion, requires fewer components for handling,
requires fewer
welding parameters, and fits in existing manufacturing tooling. FIG. 2F shows
another
exemplary embodiment of a single "twin" channel gable post design which is
also applicable to
gable headers. Single twin channels 224 are welded to gable post plate 22 with
plug welds 207
(or other suitable welds) on both sides. Slots 26 in post plate 22 allow plug
weld 208 (or other
suitable weld) from the inside. Twin channel gable post has integral interior
flanges located
where the two sloped pieces of single twin channels 224 meet at weld 208.
Extensions for wall
panel welding are moved to the channel portion of weldment and are integrated
to single twin
channels 224. This maintains a flat interior profile. The embodiment shown in
2F has additional
advantages over the embodiment shown in FIG. 2E. It provides one side welding
207 on the
interior of single twin channel 224 and plate 22, better alignment of post
gable plates 22 as it is
self-centering, and provides better control of wall panel lateral placement
allowing the interior
width to be easier to maintain.
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[0043] FIGS. 3A and 3B show an exemplary embodiment of integral top rail ledge
(or seat) 33
in upper casting 30. Upper casting 30 has an interlocking member or protrusion
35 that is
integral to casting 30. It protrudes from casting 30 and engages with a
corresponding
interlocking member 38, or notch, in channels 32 of gable post 37(or header
39) to increase
engagement with twin channel gable post 37 or gable headers 39. This allows
for a greater weld
length and enhances the strength of this critical connection. Bottom face of
ledge (or seat) 33
allows top rail 34 of the walls to "sit" on and be located by an integral
feature (with cast
components). Ledge 33 is cast into upper casting 30 and requires no additional
manufacturing
processes to benefit from upper casting 30, whereas in the prior art, the top
rails abut the upper
casting. Ledge 33 creates a seat for top rail 34 to rest against. Top rail 34
wall assembly hangs
from upper casting 30. When loaded, top rail 34 (rectangular tubing shown as
one embodiment)
is subjected to shear forces as opposed to the weld joints connecting the top
rails to the upper
castings in the prior art. This provides a stronger connection. Vertical face
of cast-in ledge 33
helps control side wall sub-assemblies' lateral location during manufacturing
helping to maintain
interior width.
[0044] In addition to conventional manufacturing, the present invention also
provides a more
efficient manufacturing process. During fabrication, top rail 34 is welded
onto side wall panels
36. This sub assembly is then incorporated into the container assembly during
subsequent
assembly steps. Side wall sub-assemblies 36 can be introduced to the
intermediate gables from
above and lowered in place until side wall sub-assemblies 36 are entirely
supported by the
intermediate gable 37. This makes fabrication easier and more efficient.
Vertical face of cast in
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ledge 33 helps control side wall sub-assemblies' lateral location during
manufacturing helping to
maintain interior width. Alternatively, top rail 34 can be welded in place
(creating a
exoskeleton) and then side wall panels 36 would be welded in place.
[0045] FIGS 4A and 4B show an exemplary embodiment of main frame cross member
sections
46 under floor 40. Cross members 46, which are not a conventional C beam, but
are a shape
having a C section, are an improvement over the conventional "I" beam
configuration. Cross
members 46 have the same sectional depth and width as conventional "I" beam
construction and
provide a stronger frame having the same overall mass. Cross members 46 have
an increased
resistance to bending and torsion over conventional "I" beam construction.
Another advantage
to the channels of the present invention over the conventional "I" beams, is
the web can be
oriented to face the front of the container (the open section facing the rear
of the container). This
eliminates the air trap created when using an "I" beam section. Eliminating
this air trap reduces
the drag created during transport and improves fuel consumption from smoother
airflow under
the container. The newly oriented web further eliminates both the acoustical
contribution of this
air trap and the dirt/mud trap that can hold moisture contributing to and/or
accelerating corrosion
of key structural elements of the container. Additionally, the web dimension
of the C shaped
cross members 46, is one continuous length as opposed to those in the "I- beam
that are
interrupted mid span by the web itself. This allows for one continuous weld
bead to fully weld
the C shaped channel to the respective lower main rail, ensuring a better weld
with fewer start
and stops and minimizing potential variability in the welded connection. This
also ensures better
weld penetration and does not subject the structural members to extra heat
created with
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additional weld joints, safeguarding the metallurgical properties of the
steel. Due to the side
located web, the "C" channel also allows for a wider, uninterrupted flange in
which to locate
floor screws. This greatly enhances installation of the floor and prevents
holes from being drilled
into the web, in comparison to a conventional "I" beam structure which
requires holes being
drilled into the web and compromises its structural integrity.
[0046] FIG. 5A shows the prior art rear contact plate 52. Contact plate 52
consists of multiple
separate pieces attached to roof 56 and door header 51. FIGS. 5B, 5C, 5E and
5D show
continuous one-piece rear contact plate or door header top plate 50. Door
header top plate 50
includes an integral rear roof filler piece, integral lip 54, that provides a
connection point for rear
roof 56. Lip 54 provides a stronger roof system. Overhang 58 shields upper
door rod keepers,
reducing the propensity for damage of the container during use and handling.
Door header top
plate 50 eliminates the piece count of conventional contact plate 52 and
unnecessary weld joints.
Door header top plate 50 also eliminates chronic leak points and several catch
points reducing
the propensity of damage to the container during use and handling. Door header
top plate 50
with overhang 58, as shown in FIGS. 5C and 5D, eliminates all four contact
plates and
associated filler pieces, numerous welding operations, and numerous potential
leak points of the
prior art and permits a stronger flange on which to allow the front/rear roof
assemblies to rest
during fabrication.
[0047] FIG. 6 shows an alternate view of door header top plate 60 with
integral rear roof filler
piece, integral lip 64. Integral lip roof filler piece 64 is close in the area
in the roof where the
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structural elements of the front and rear gables meet the front and rear roof
assemblies,
respectively. The current practice is to weld a horizontal plate onto the top
member of the
front/rear gables that extends towards the inside of the container. All four
exterior corners of the
container require a contact plate to be present. This is conventionally
achieved by welding a
suitable steel piece in each corner along with multiple little filler pieces
that close in openings
created by the mating geometry. The present invention provides a rear lower
edge 66 of the door
header top plate 60 having a radiused profile to facilitate door gasket 68.
The roof panel sits on
integral lip 64. Door Gasket 68 on door 62 resolves the chronic problem of
door gasket wear
which results in water ingress into the container reducing the propensity for
damage during use
and increasing the service life of door gasket 68. The same door header top
plate with integral
roof filler can also be used on the front roof, front top plate, as seen in
FIGS. 8A, 8B and 8C.
[0048] In another embodiment of the present invention, FIGS. 7A and 7B show
exemplary
embodiments of a rear header, door header 70 in FIG. 7A and door sill (or rear
bolster) 74 in
FIG. 7B. Headers 70, 74, can also have integral internal gussets 72, 76, that
further enhance the
strength of these assemblies. Internal gussets 72, 76, can be aligned with the
door lock rod
keepers, enhancing their support and security of the container when locked. In
addition, there is
an added advantage to the integral internal gussets 72, 76 in the rear bolster
(door sill) 74. They
can also be aligned with the track width of conventional forklift wheels to
help resist impact
loading that the rear bolster (door sill) is typically and repeatedly
subjected to. Over time, this
can result in the rear bolster (door sill) becoming "crushed." A damaged rear
bolster (door sill)
constitutes a compromised structural integrity of the rear gable and the
container as a whole
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system. A damaged rear bolster may not sit properly on a chassis and may
impair the effective
sealing of the door gasket.
[0049] FIG. 8A shows the prior art front contact plate design 81. Contact
plate design 81
consists of multiple separate pieces attached to roof 86. FIGS. 8B and 8C show
an exemplary
embodiment of the continuous one-piece front contact plate, front top plate
80. Front top plate
80 eliminates the piece count of conventional contact plate 81 and unnecessary
weld joints and
potential chronic leak points. Front top plate 80 also eliminates several
catch points reducing the
propensity of damage to the container during use and handling. Front top plate
80 has an integral
front roof filler piece, integral lip 84, that provides a connection point for
front roof 86. Integral
lip 84 provides a stronger roof system.
[0050] FIGS. 9A and 9B show an exemplary embodiment of a rear lower casting
profile 91.
Most conventional container designs have the door sill abut rear corner posts
with the rear lower
casting welded below. This creates a stress concentration point at this welded
connection that can
(and tends to) crack over time. Rear lower casting 91 prevents the stress
concentration point
damage by moving the stress concentration point from a welded joint to the
casting itself which
is now integral to the connection. An integral interlocking casting 91 is the
interface between
door sill 90 and rear corner post 92. Casting 91 has integral interlocking
members, protrusion,
94, that interlock with corresponding interlocking members, notches 96, on
members such as rear
post 92 and/or door sill 90. Door sill 90 connects and sits in casting 91.
Rear post 92 connects
with and sits on casting 91. Casting 91 eliminates the chronic weld fatigue
point. Casting 91
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allows for a longer weld length joining the rear lower casting 91 to rear
corner post 92. Casting
91 has a lateral observation hole 93 to view the chassis twist lock from the
side of the container.
This increases safety to ensure the chassis twist lock has been properly
engaged when the
container is in transport.
[0051] Most containers have wooden floors (some containers have aluminum or
other flooring
material) 102 that are fastened to structural frame elements to permanently
retain the floor. FIG.
10A shows the conventional design of front or rear intermediate bolster 101.
It is a channel and
plate design 103 with angle irons 105. Floorboards 102 are fastened to angle
irons 105. FIG.
10B shows an exemplary embodiment of a front or rear intermediate bolster 100
with integral
floor supports 104 of the present invention. The intermediate bolsters form a
"ring" with the
intermediate gables and headers. Intermediate bolster 100 is flush with the
top surface of
flooring 102. Intermediate bolster 100 provides a seating and fastening
surface 104 for floor 102
to attach. Flooring 102 is fastened to structural frame elements to
permanently retain the floor.
Floors may be made of any suitable material such as wood, plastic or aluminum.
Intermediate
bolster 100 reduces the piece count and eliminates the need to weld additional
metal pieces, such
as the weld beads required by angle irons 105. Added heat from additional weld
beads
negatively impacts material properties and strength of intermediate bolsters.
Intermediate bolster
100 reduces the weld joints and therefore safeguards the metallurgical
properties of the steel.
Intermediate bolster 100 can also have integral internal gussets, similar to
the rear headers, for
enhanced strength. Slots 106 in Intermediate bolster 100 allow for plug (or
suitable) weld beads
Gussets are welded to the "hat- portion of bolster 100. During manufacturing,
the gussets are
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welded in place inside channel 108 of bolster 100. The "hat" portion of
bolster 100 is then
welded to channel. Gussets in conjunction with slots 106 contribute greatly to
the strength of
bolster 100 once all is welded together as a sub-assembly. Gussets can be
aligned with track
width of conventional forklifts to prevent "crushing" of intermediate bolster
100.
[0052] Conventional containers have a channel and pressed plate rear corner
post. This
arrangement results in an inherent gap or void in the region between the rear
corner post and the
rear lower side rail, creating a dirt/mud trap that can hold moisture
contributing to and/or
accelerating corrosion of key structural elements of the container.
Additionally, there is no way
to smoothly transition the rear lower siderail to the inner edge of the rear
corner post plate. In
the prior art, the gap/ void created can lead to a hang up point for cargo
during loading/unloading
and cause damage to the containers or the cargo. FIGS. 11A and 11B show an
exemplary
embodiment of the nested rear corner post design 111 of the present invention.
Rear corner post
111 differs from a conventional rear corner post because it has interlocking
members such as
notch 114 and protrusion arrangement The lower rear casting protrusion 116
engages with
notch 114 located in read corner post 111. Notch 114 is located in rear corner
post 111 and
protrusion 116 is an integral feature of the lower rear casting 118. The
shapes of the notch and
the protrusion correspond with one another. The corresponding shapes of the
interlocking
members may be a symmetrical sloping shape, such as a trapezoid. The
"trapezoidal" shape, as
shown, allows the steel member to be self-centered when introduced to the
casting (or vice versa)
and minimizes stress concentrations caused by 90 degree angles of square
shaped. The present
invention eliminates gaps/ voids of the prior art. In doing so, nested rear
corner post 111 creates
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a strong door opening and eliminates problems created by voids. Rear lower
side rail 115 is
welded to door gable 111. With the nested design of the present invention,
flange 117 is
specifically provided for this weld joint. Flange 117 is also welded to the
inner portion 113 of the
rear corner (door) post sub-assembly. This allows for an additional weld bead
to be applied to
this critical corner of the container.
[0053] Currently, all intermodal containers are governed by a maximum of
67,200 lbs for the
combined mass of the container and the cargo it can be loaded with and safely
moved. When the
tare weight of the container is reduced, it permits an increase in permissible
cargo carrying
capacity which is a competitive advantage to customers. Subsequently, the
increase in internal
volumetric payload capacity enabled by, for example, 100-1/2" internal width
also allows for
advantages, as most cargo limitations are typically volumetric in nature, not
mass.
[0054] Ultra-high strength steel (100ksi yield) preferably should be used in
key locations to
enable the design. Additionally, the upper castings preferably should be cast
steel having a grade
of ASTM A-27 GRADE 70-40 [485-275] (UNS J02501) or SCW480 or equivalent to be
serviceable.
[0055] Although the present invention has been described in conjunction with
specific
embodiments, those of ordinary skill in the art will appreciate the
modifications and variations
that can be made without departing from the scope and the spirit of the
present invention.
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