This disclosure generally relates to railcars, and more particularly to intermodal well cars.
Railcars, such as well cars, include side sheet assemblies that, in some railcars, support the load of freight carried within the railcar. An intermodal well car is a type of railcar designed to transport intermodal containers (shipping containers). An intermodal container is a standardized (length, width, etc.) container for transporting freight using multiple modes of transportation (e.g., rail, ship, truck, etc.). The well of the intermodal well car creates a floor lower than a traditional flatcar. The recessed well facilitates stacking of two intermodal containers (a double-stack) without exceeding height limitations for safe passage under bridges, through tunnels, and other structures.
Well cars, including intermodal well cars, conventionally are constructed using side sheet assemblies that transfer a load from a top chord of the well car to the side sill near the bottom of the well car. Transporting shipping containers may require side sheet assemblies that are capable of transferring large loads based on the weight of the shipping containers. For example, each container may weight up to 52,900 pounds or 67,200 pounds for twenty-foot and forty-foot International Standards Organization (ISO) containers, respectively. To accommodate the load of this freight carried in the well cars, these side sheet assemblies conventionally require a complex construction including multiple layers of sheet metal organized in different overlapping positions to create different thicknesses of the side sheet assembly and additional support structures, such as channels, to stiffen sections of the side sheet assembly that would be subject to higher loads. This complex construction is both resource intensive, requiring several processes to create a single side sheet assembly, and introduces an unnecessary number of construction failure points at the points of welding the plurality of side sheets and support structures together during assembly.
A more complete and thorough understanding of the particular embodiments and advantages thereof may be acquired by referring to the following description taken in conjunction with the accompanying drawings, in which like reference numbers indicate like features, and wherein:
According to an embodiment, a railcar frame includes a first side sheet assembly. The first side sheet assembly includes a first side sheet, a first top chord, and a first side sill. The first side sheet includes one or more truss structures formed within the first side sheet by removing a plurality of portions of the first side sheet according to a pattern. The first side sheet has a length along a first axis and a width along a second axis perpendicular to the first axis. The first top chord is welded to a top portion of the first side sheet along the first axis. The first side sill is welded to a bottom portion of the first side sheet along the first axis opposite the first top chord.
In particular embodiments, the railcar frame further includes a second side sheet assembly. The second side sheet assembly includes a second side sheet, a second top chord, and a second side sill. The second side sheet includes one or more truss structures formed within the second side sheet by removing a plurality of portions of the second side sheet according to the pattern. The second side sheet has a length along the first axis and a width along the second axis perpendicular to the first axis. The second top chord is welded to a top portion of the first side sheet along the first axis. The second side sill is welded to a bottom portion of the first side sheet along the first axis opposite the second top chord. The first side sheet assembly and the second side sheet assembly are coupled together.
According to another embodiment, a method includes providing a first side sheet having a length along a first axis and a width along a second axis perpendicular to the first axis. The method further includes forming one or more truss structures within the first side sheet by removing a plurality of portion of the first side sheet according to a pattern. The method further includes welding the first side sheet to a top chord and a side sill to form a first side sheet assembly of a frame for a railcar.
In particular embodiments, the method further includes providing a second side sheet having a length along a first axis and a width along a second axis perpendicular to the first axis. The method further includes forming one or more truss structures within the second side sheet by removing a plurality of portions of a sheet of metal according to the pattern. The method further includes welding the second side sheet to a second top chord and a second side sill to form a second side sheet assembly of the frame of the railcar. The method further includes coupling the first side sheet assembly and the second side sheet assembly together.
Certain embodiments described herein may have one or more technical advantages. For example, certain embodiments provide a side sheet assembly that include fewer components to assemble, thereby lowering the complexity of construction. As another example, the reduction in the number of components may reduce the number of weld terminations, thereby reducing the points of potential weld and/or fatigue failure. As yet a further example, certain embodiments provide a side sheet assembly that are reduced in weight compared to conventional side assemblies, which allows an increased freight capacity. As yet another example, the simplified geometry and construction of the side sheet assembly according to certain embodiments allows an easier process to coat and paint the surface of the railcar, increasing the coverage of protective coatings on the railcar.
Certain embodiments described herein may have one, none, or more than one of the above-described advantages or other advantages as recognized by a person having ordinary skill in the art.
Conventional side sheet assemblies for railcars, such as well cars, conventionally require a complex construction including a plurality of side sheets that are welded together in different overlapping positions to create a single side sheet assembly suitable to handle the load of the shipping containers. Additionally, typical well car side sheet assemblies also include support structures, such as channels, fastened to the side sheets to provide extra load support at particular locations on the side sheet assembly. The assembly of the side sheet assembly typically requires fastening these various components, e.g., by welding side sheets and support structures together, which creates multiple potential failure points. Having more potential failure points may increase the failure rate of the side sheet assembly, thereby reducing the effective lifespan of the assembly or decreasing the time between reassembly or maintenance. Furthermore, the complex assembly requires multiple processes to create the side sheet assemblies, thereby increasing the possibility of non-uniform construction and/or wasted resources.
Accordingly, this disclosure contemplates side sheet assemblies that are simpler to construct and provide similar or better support for railcars. While the example of a well car may be used throughout the disclosure to describe certain embodiments, certain embodiments of side sheet assemblies discussed herein may be used with any suitable type of railcar transporting freight.
Particular embodiments and their respective advantages are best understood by reference to
Support structures 22, such as channels, may be added to further support the construction of well 14 by coupling support structures 22 with side sheets 20 and between top chords 16 and side sills 18. For example, a support structure 22 may be provided near the midpoint along the length of well 14 and at the ends of the side of well 14 to support the increased load usually present near those locations. In some embodiments, support structures 22 may be a series of posts, stiffeners, or channels that are fastened to sides sheets 20 to support load bearing of well 14.
In certain embodiments, well car 10 includes or is an articulated railcar. An articulated railcar includes multiple wells 14 (e.g., two to five wells 14). Each of multiple wells 14 may be configured to hold one or two containers 15. Each well 14 or well structure may be connected to another well 14 via a truck, such as truck 12. In some embodiments, each well 14 includes a plurality of side sheets 20 connected together to form the sides of well 14 between their respective side sills 18 and top chords 16. Accordingly, each well 14 of an articulated railcar may be construed in a similar manner described above and have an increased container capacity.
In certain embodiments, the distribution of weight on well 14 may be uneven or localized more heavily in certain locations on portions of well. For example, in some embodiments, weight is distributed across the length of well 14, but the load is highest at the ends of well 14 and in the middle of well 14. In certain embodiments, the construction of well 14 may reflect the load distribution based on the construction the side of well 14 including how side sheets 20 and support structures 22 may are positioned and oriented together in the construction of the side sheet assembly. For example, additional overlap or stronger side sheets 20 may be coupled together proximate the ends of well 14 and/or near the middle of well 14. As another example, additional or stronger support structures 22 may be located near the higher load points. In this manner, the load of containers 15 may be accommodated in well 14 of well car 10.
These components and construction techniques may increase the reliability of well 14 in supporting the weight of the containers 15 but also introduces additional complexity and cost in assembling well 14. For example, the methods used to assemble side sheets 20 may introduce additional welding points or connections between constituent parts of well 14, which may increase the number of failure points. As another example, having variable thickness of side sheets 20 to accommodate the localized load points may require different processes in providing different side sheets and coupling side sheets 20 together. Further, the addition of support structures 22 may also introduce additional complexity, requiring additional welding and more difficult welding to couple support structures 22 and side sheets 20 with top chords 16 and side sills 18.
Accordingly, what is desired is an improved assembly and method of assembly for the sides of wells in well cars. This disclosure contemplates an improved side sheet assembly that is simpler to construct and provides similar or better support for railcars by utilizing a metal side sheet from which material is removed to form integral trusses. Such assemblies may provide advantages by reducing the complexity of construction while maintaining load strength. Embodiments of the improved designs will be described using
Truss plate 40 may include one or more sheets of metal. For example, in certain embodiments, truss plate 40 includes multiple sheets of metal fastened together to create a uniform thickness metal plate of a specified length. As another example, truss plate 40 may be constructed from a single metal plate, such as a single sheet of metal. In certain embodiments, truss plate 40 is constructed from a monolithic side sheet. The thickness of truss plate 40 may configured based on the desired load characteristics and weight considerations in the construction of well car 10. As described in further detail below, truss plate 40 may be used in constructing well 14 while simplifying its construction while maintaining structural support for the container load.
Truss plate 40 may be constructed by cutting or punching out (or otherwise removing) portions from a single metal sheet, in accordance with certain embodiments. For example, truss plate 40 may include one or more removed portions 42. Removed portions 42 may have any suitable shape, including triangular shapes. For example, orienting removed portions 42 with a triangular shape in an alternating pattern may form one or more trust structures 44 in truss plate 40. Truss structures 44 may provide the structural stability to truss plate 40 while still removing weight of the metal sheet at removed portions 42. In this manner, truss plate 40 may include one or more truss structures 44 that are integrated into a monolithic structure, thereby eliminating the need to separately fasten trusses, which requires additional processing and introduces potential fastening failure points.
In other embodiments, removed portions 42 may be non-uniform or have one or more different shapes, including non-triangular shapes. For example, in certain embodiments the shapes and or sizes of removed portions 42 may vary across truss plate 40. For example, the size and shape of removed portions 42 may differ based on the location or proximity to different locations along the length of side sheet assembly 30. As a result, the size and shape of truss structures 44 may differ along the length of side sheet assembly. For example, the size and/or shape of removed portions 42 may differ based on proximity to one or more ends of the side sheet assembly 30. In particular, removed portions 42 are smaller or are less dense near the ends of the side sheet assembly 30, as shown in
Although
In certain embodiments, truss plate 40, including the distribution and orientation of removed portions 42 and truss structure 44 may be based on the expected load distribution on side sheet assembly 30. For example, as described above in relation to well car 10, the load carried by well car 10 may be localized near the ends and near the middle of the sides of well 14. Instead of overlaying multiple sheets or thicker or additional sheets near those increased load points, truss plate 40 may include stronger zones where there is more material, e.g., less removed portions 42 and more or thicker truss structures 44 proximate those areas. For example, in locations where a higher load is expected, truss plate 40 may include less removed material. As show in the illustrated example in
If constructed from a single sheet of metal, truss plate 40 may not require any welding or other fastening prior to its assembly with top chord 36 and side sill 38, according to certain embodiments. For example, if truss plate 40 is constructed out of a monolithic sheet of metal, the only processes necessary to construct truss plate 40 are the removal of removed portions 42. This may include grinding or punching out removed portions 42, which does not introduce welding points that run the risk of failing. Accordingly, the construction of truss plate 40 is greatly simplified compared to conventional side sheet assemblies described above. For example, truss plate 40 would not require the need to weld or otherwise fasten multiple sheets together and avoids the problems associated in traditional side sheet assemblies that require multiple sheets to be overlaid and welded in different configurations to support the load of well car 10. In this manner, side sheet assembly 30 may reduce the number of weld terminations, thereby reducing the number of potential weld or fatigue failure points.
The construction of truss plate 40 by removing removed portions 42 does not limit the use of additional support structures to further enhance the load characteristics of side sheet assembly 30. For example, in certain embodiments, truss plate 40 may be reinforced by one or more support structures 46, such as support structures 22 used in in conventional well cars. In some embodiments, less support structures 46 are used than in conventional well cars. For example, truss plate may only include a single support structure 46 at the middle of side sheet assembly 30. Alternatively, truss plate 40 may include no additional support structures other than the connections with top chord 36 and side sill 38. For example, as discuss above, the relative strength of portions of truss plate 40 may be controlled by the size, shape, and location of removed portions from truss plate 40. Accordingly, no or less support structures 46 may be needed, because the strength of truss plate 40 may be optimized to have the requisite increased strength at those locations based on the distribution of removed portions 42 without external structures. Accordingly, the number of weld terminations required to join truss plate 40 may be reduced.
Additionally, the reduction or removal of support structures 46 may simplify the geometry and construction of the side sheet assembly, according to certain embodiments. For example, truss plate 40 may have one or more a flat surface, which may allow an easier process to coat and paint the surface of side assembly 30 by increasing the coverage of protective coatings. If certain locations are not coated, those locations may form rust or other degradation spots that may spread and negatively affect the structure of side sheet assembly 30 and well car 10. In particular, if no support structures need to be added, the coating surface of truss plate 40 may remain flat, which makes paint and other protective coatings easier to apply and to ensure uniform and complete of coverage.
At step 520, one or more truss structures are formed within the first side sheet. In particular, a plurality of portions of the first side sheet may be removed according to a pattern to form the one or more truss structures. For example, an alternating pattern of triangular shapes removed from the first side sheet may cause the formation of alternating truss structures within the first side sheet. Forming the truss structures within the first side sheet reduces the amount weld terminations and processing required by conventional techniques that require fastening separate components to form trusses.
The pattern used to remove portions of the first side sheet may be any suitable pattern resulting in a structurally sound first side sheet. For example, the pattern may be based on the desired load capacity of the side sheet and frame of the railcar. In particular, the pattern may call for the removal of the maximum amount of material from the first side sheet without reducing the load capacity below a predetermined threshold. As another example, the pattern may have a non-uniform density of removed portions of the side sheet. The density provided by the pattern may be based on an anticipated load distribution, thereby accounting for an increased load by increasing the truss strength at high-load points by increasing the thickness of the trusses near those high-load points. Any suitable method of removing the portions from the first side sheet are contemplated herein, including cutting, grinding, or punching out the portions of the first side sheet.
Once the truss structures have been fully formed within the first side sheet, at step 530, the first side sheet is welded to a top chord and a side sill to form a first side of a frame for a railcar. The top chord may run across the length of the first side sheet across a top of the first side sheet and the side sill along the length of the first side sheet across a bottom of the first sheet on the opposite side. In this manner, an improved side sheet assembly, e.g., side sheet assembly 30 with truss plate 40 together with top chord 36 and side sill 38, may be constructed. The side sheet assembly may be integrated as part of the frame of a well car or any other suitable railcar.
Modifications, additions, or omissions may be made to method 500 depicted in
As a result, particular embodiments of the present disclosure may provide numerous technical advantages. For example, certain embodiments provide a side sheet assembly that include fewer components to assemble, thereby lowering the complexity of construction. As another example, the reduction in the number of components may reduce the number of weld terminations, thereby reducing the points of potential weld and/or fatigue failure. As yet a further example, certain embodiments provide a side sheet assembly that are reduced in weight compared to conventional side assemblies, which allows an increased freight capacity. As yet another example, the simplified geometry and construction of the side sheet assembly according to certain embodiments allows an easier process to coat and paint the surface of the railcar, increasing the coverage of protective coatings on the railcar.
Although several embodiments have been provided in the present disclosure, it should be understood that the disclosed systems and methods might be embodied in many other specific forms without departing from the spirit or scope of the present disclosure. The present examples are to be considered as illustrative and not restrictive, and the intention is not to be limited to the details given herein. For example, the various elements or components may be combined or integrated in another system or certain features may be omitted, or not implemented.
In addition, techniques, systems, subsystems, and methods described and illustrated in the various embodiments as discrete or separate may be combined or integrated with other systems, modules, techniques, or methods without departing from the spirit or scope of the present disclosure. Other items shown or discussed as coupled or directly coupled or communicating with each other may be indirectly coupled or communicating through some interface, device, or intermediate component whether electrically, mechanically, or otherwise. Other examples of changes, substitutions, and alterations are ascertainable by one skilled in the art and could be made without departing from the spirit and scope disclosed herein.
This application claims the benefit of Provisional Application Ser. No. 62/628,342, filed on Feb. 9, 2018 and entitled “TRUSS PLATE SIDE SHEET ASSEMBLY,” the contents of which are incorporated by reference herein in their entirety.
Number | Date | Country | |
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62628342 | Feb 2018 | US |