The present invention is related in general to railway cars having one or more straight sides and particularly to railway cars with straight sides formed in part by side sheets and side posts.
Railway cars are useful for transporting large amounts of cargo. Although in some applications it is desirable to manufacture large railway cars, the Association of American Railroads (AAR) has placed constraints on the size of railway cars for safety purposes. For example, cross-sectional widths and heights of railway cars are generally limited by applicable AAR clearance limitations, which specify a maximum width and a maximum height of a railway car at the center of the railway car and also specify maximum heights and widths at other locations along the length of the railway car. Because of applicable AAR clearance limitations, designers often increase the cargo carrying capacity of a railway car by increasing the length of the railway car. Unfortunately, as the length of a railway car increases, the width allowed by applicable AAR clearance limitations decrease to take into account the travel of the railway car around a curve. While traveling around a curve, a portion of a railway car may extend outside a clearance plane specified by AAR limitations, which is not acceptable. Therefore, stricter width clearance limitations are applied to longer railway cars to avoid a long railway car making contact with a structure adjacent the railroad.
Thus, AAR clearance limitations also generally limit the width-to-length ratio at which a railway car may be constructed and therefore further restrict cargo carrying capability of a railway car. The amount of cargo a railway car may carry directly impacts profitability of a railway carrier and is therefore important. Thus, maximizing the amount of cargo a railway car can carry while staying within AAR clearance limitations is desirable.
In accordance with a particular embodiment, a railway car includes a railway car underframe having a first longitudinal side sill and a second longitudinal side sill with at least one sidewall assembly disposed along the first longitudinal side sill of the railway car underframe. The sidewall assembly is formed in part from a side sheet, an interior vertical support post, and an exterior vertical support post. A first end of the interior vertical support post and a first end of the exterior vertical support post are each respectively disposed adjacent to the first longitudinal side sill of the railway car underframe. The exterior vertical support post is coupled to an exterior surface of the side sheet. The interior vertical support post is coupled to an interior surface of the side sheet.
In accordance with a particular embodiment, a railway car includes a railway car underframe having a first longitudinal side sill and a second longitudinal side sill with a first sidewall assembly disposed along the first longitudinal side sill of the railway car underframe and a second sidewall assembly disposed along the second longitudinal side sill of the railway car underframe. Each of the first and second sidewall assemblies include first and second side sheets, a plurality of interior vertical support posts proximate a center of the railway car, and a plurality of exterior vertical support posts positioned between the plurality of interior vertical support posts and an end of the railway car. Each exterior vertical support post is coupled to an exterior surface of a side sheet of the first and second side sheets, and each interior vertical support post is coupled to an interior surface of a side sheet of the first and second side sheets.
In accordance with a particular embodiment, a method of forming a railway car includes coupling first and second sidewall assemblies to a railway car underframe. Each of the first and second sidewall assemblies include first and second side sheets, a plurality of interior vertical support posts proximate a center of the railway car, and a plurality of exterior vertical support posts positioned between the plurality of interior vertical support posts and an end of the railway car. Each exterior vertical support post is coupled to an exterior surface of a side sheet of the first and second side sheets, and each interior vertical support post is coupled to an interior surface of a side sheet of the first and second side sheets.
Technical advantages of particular embodiments include a railway car with exterior and interior support posts positioned to give the railway car an hourglass formation. This increases cargo carrying capacity and length while the railway car remains within applicable AAR clearance limitations. Also, a railway car may be made shorter than corresponding conventional railway cars, while having the same or greater cargo carrying capacity. Moreover, the exterior and interior configuration of the support posts disclosed herein provide a solid structure for the railcar despite adding discontinuities which, in the past, have been discouraged and avoided.
Further technical advantages of particular embodiments include vertical support posts disposed on the interior of the railway car to reduce or eliminate cavities where lading might become lodged. Such interior vertical support posts may have a modified hat-shaped cross section that includes legs that gently slope away from a center portion of the post.
Other technical advantages will be readily apparent to one of ordinary skill in the art from the following figures, descriptions, and claims. Moreover, while some specific advantages have been enumerated above, various embodiments may include all, some, or none of the enumerated advantages.
A more complete understanding of embodiments of the invention will be apparent from the detailed description taken in conjunction with the accompanying drawings in which:
Preferred embodiments of the disclosure and some advantages are best understood by reference to
The terms “side post,” “side post” “support post,” and “support post” may be used in this application to describe any post operable to support side sheets of a sidewall or sidewall assembly associated with a railway car. Corner posts, typically located at respective joints between side walls and end walls, may sometimes be included in the definition of “side post,” “side post,” “support post,” and “support post” for purposes of describing and claiming various features of the present invention.
For purposes of illustration, the present disclosure may be described with respect to railway cars such as gondola cars and/or hopper cars. Examples of such railway cars are shown and described in U.S. Pat. No. 5,209,166, entitled “Railway Hopper Car Bolster Assembly”; U.S. Pat. No. 4,633,787 entitled “Light Weight Gondola Type Railway Car”; U.S. Pat. No. 3,844,229, entitled “Railway Hopper Car End Structure Assembly”; and U.S. Pat. No. 3,785,754, entitled “Rapid Discharge Hopper Car”. Although the present disclosure may be generally described with respect to covered railway cars, a sidewall or sidewall assembly incorporating teachings of the present disclosure may be used with a wide variety of railway cars such as open top hopper cars and gondola cars.
For some applications railway car 20 includes a railway car underframe indicated generally at 30 with car body 40 mounted thereon. For some applications, railway car underframe 30 and car body 40 may be manufactured from steel alloys. However, various components of both railway car underframe 30 and car body 40 may be satisfactorily formed from various steel alloys, aluminum alloys, fiber reinforced plastic materials, cermets, and composites of these materials as desired. As discussed later in more detail, fabricating a railway car with sidewalls or sidewall assemblies having side posts and side sheets formed in accordance with teachings of the present disclosure may increase load carrying capacity and still allow a railway car to fit within the AAR clearance dimensions.
Railway car underframe 30 may be attached to and mounted on first railway truck assembly 31 adjacent to first end 21 of railway car 20. Railway car underframe 30 may also be attached to and mounted on second railway truck assembly 32 adjacent to second end 22 of railway car 20. Railway car underframe 30 may include a pair of body bolsters (not expressly shown) satisfactory for engagement with respective railway truck assemblies 31 and 32. Various types of commercially available railway car underframes and railway truck assemblies may be satisfactorily used with the present invention.
Car body 40 may include a pair of sidewall assemblies 50 which extend generally parallel with each other along opposite sides of railway car underframe 30. Sidewall assemblies 50 may also be defined in part by respective exterior surfaces 56 and interior surfaces 58. For some applications, sidewall assemblies 50 may be formed from a plurality of generally rectangular side sheets 70 which may be attached to each other using various types of mechanical fasteners and/or welding techniques.
The arrangement of side sheets 70 may be modified depending upon the desired configuration of the resulting sidewall assembly. Side sheets 70 cooperate with each other to form exterior surface 56 and interior surface 58 of associated sidewall assembly 50. Portions of each sidewall 50 and associated side sheets 70 proximate first end 21 and second end 22 of railway car 20 may have generally tapered portions 51 and 53. Side sheets 70 cooperate with each other to form exterior surface 56 and interior surface 58 of associated sidewall 50.
For some applications, railway car underframe 30 may have a generally rectangular configuration defined in part by a pair of side sills 34. Portions of side sill 34 are shown in
As shown in
Various types of mechanical fasteners such as nuts and bolts, drive bolts, blind rivets, and other fasteners may be satisfactorily used with the present invention. Examples of such fasteners are available from Huck International, Inc. located at 6 Thomas, Irvine, Calif. 92718-2585. Power tools satisfactory for installing such fasteners are also available from Huck International and other vendors. For some applications various welding techniques may be used to satisfactorily attach respective top chords 60 with a respective upper portion of each sidewall. Also, a combination of welding techniques and mechanical fasteners may also be satisfactorily used.
For some applications, car body 40 may include a plurality of cross braces and/or diagonal braces (not expressly shown) disposed between interior surfaces 58 of sidewall assemblies 50. Various types of brackets (not expressly shown) may be used to attach the cross braces and diagonal braces with associated portions of side posts 80i and 80e.
Railway car 20 may include a plurality of support posts or side posts 80i and 80e which are spaced longitudinally from each other along sidewall assembly 50. Side posts 80 may be on the outside of side sheet 70, and side posts 80i may be on the inside of side sheet 70. A particular embodiment may include a total of twenty-two side posts 80e and 80i. It may include two sections of eight exterior side posts 80e separated by a section of six interior side posts 80i. For each sidewall assembly 50, one exterior side post 80i may be located over a centerline of first truck assembly 31 and another over centerline of second truck assembly 32. A section including exterior side posts 80e may extend approximately thirteen feet along sidewall assembly 50. In addition, partitions of railway car 20 may also provide structural support. As such, the spacing of side posts 80i and 80e may vary depending on the locations of the partitions and the need for vertical support for railway car 20.
For some applications side posts 80e and 80i may be formed from aluminum or steel alloy materials. Side posts 80i and 80e may have different configurations and dimensions. In some embodiments the spacing between outside side posts 80e may change along the car. For example, the distance between two adjacent outside posts 80e may decrease as one moves towards the outside posts 80e closest to the center of the railcar. In addition, in some embodiments some outside posts 80e closer to the center of the railcar may be shallower, or have a smaller depth, than outside posts 80e that are further away from the center of the railcar.
For some applications side sheets 70 may be formed from the same aluminum alloy material as side posts 80i and 80e. For other applications, side sheets 70 may be formed from steel alloys or other suitable materials.
Side posts 80i may have modified hat-shaped cross sections formed in part by web 82i with respective legs 83i and 84i extending therefrom. Side posts 80i may be an aluminum extrusion. Legs 83i and 84i may gently slope from web 82i to flanges 85i and 86i respectively. The slope of legs 83i and 84i may form an obtuse angle with flanges 85i and 86i respectively. Such configuration of side posts 80i, and particularly legs 83i and 84i, may eliminate cavities where lading might become lodged. Thus, railway car 20 may completely unload its payload. Lading that may be completely unloaded with the benefit of such configuration of interior side posts 80i may be a corn byproduct of ethanol production transported in railway car 20.
Various techniques such as mechanical fasteners and/or welding may be satisfactorily used to attach side posts 80i and 80e with adjacent portions of associated side sheets 70. Side posts 80i and 80e may be riveted, bolted, glued, or bonded to side sheets 70. Side post 80e may have a greater moment of inertia than side post 80i. Thus, the configuration of side post 80e may be more efficient than the configuration of side post 80i. However, the configuration of side post 80i may be more aerodynamic than the configuration of side post 80e.
Railway car 20 may include a plurality of hoppers defined in part by one or more transfer ridges 42 which extend laterally across the floor of car body 40. Transfer ridges 42 and associated slope sheets 44 cooperate with each other to direct coal or similar lading toward associated discharge door assemblies 38. Each discharge door assembly 38 may include openings (not expressly shown) with a respective door or gate (not expressly shown) attached thereto. Discharge door assemblies 38 allow discharge of bulk lading such as coal by gravity from respective hopper portions of car body 40.
Discharge door assemblies 38 may be disposed adjacent to respective slope sheets 44. Slope sheets 44 may be inclined at an angle with respect to railway car underframe 30. For some applications, partitions (not expressly shown) may be provided within car body 40 to separate discharge door assemblies 38 and associated hopper portions from each other. For some applications, discharge door assemblies 38 may be automatically opened while railway car 20 is in motion to reduce unloading time. Such railway cars may sometimes be referred to as rapid discharge cars. For some applications, railway car 20 may also be modified to accommodate unloading by using rotary dumping equipment and techniques.
Side sill 34 may have a generally L-shaped cross section and may run substantially along the length of railway car 20 to provide structural support for side assembly including side posts 80e and 80i. Side sill 34 may have an exterior portion 33 and an interior portion 35. Top chord 60 may be attached along the upper edge of side wall 70. Top chord 60 may include an elongated hollow beam or tube extending substantially along the full length of respective side wall assembly 50.
The clearance limitations for widths of railway cars over a certain length require a smaller width near the center of railway car 20 then at its ends. Thus, a configuration utilizing vertical side posts located on the interior of railway car 20 may maximize cargo-carrying space. The increased cargo-carrying capability may arise from the ability to provide a larger railway car 20 having length 96 that is longer than conventional railway cars. Railway car 20 may be longer than convention railway cars because width 92 near the center of railway car 20 is reduced to meet AAR limitations. If width 92 were increased such that width 92 equaled width 94, AAR limitations would require a shorter length, which would reduce cargo carrying capability.
The maximum width of a standard rail car may be 10′8″. However, if the railway car is made longer, then it must have a width of less than 10′8″ near the center of the railway car. This requirement is governed by AAR limitations in order to ensure that a longer railway car is able to travel around a curve without overhanging a portion of the rail car near the center on the inside of the curve. The standard AAR curve from which the limitations are derived may be a 13° arc and an associated radius of 441.68 feet. In a straight sided rail car, the AAR limitations may be met by making the side sill concave near the center. However, railway cars must be capable of withstanding considerable buff and draft forces during normal operation of the rail car. Incorporating a concave sill and vertical support posts that may not be properly aligned due to the concave nature of the center of the railway car may reduce the railcar's ability to withstand these considerable forces.
In addition, as discussed above, the spacing between outside side posts 80e may change along the car. For example, the distance between two adjacent outside posts 80e may decrease as one moves towards the outside posts 80e closest to the center of the railcar. This is evident in
In addition, as discussed above in some embodiments some outside posts 80e closer to the center of the railcar may be shallower, or have a smaller depth, than outside posts 80e that are further away from the center of the railcar. This too is evident in the embodiment shown in
As discussed, the use of interior side posts 80i near the center of the railcar and exterior side posts 80e away from the center give the railcar a preferred hourglass shape with a width smaller at the center of the railcar and increasing away from the center. In addition, the increasing depth of exterior side posts 80e as one moves away from the center further facilitates the hourglass configuration having an increasing width away from the center of the railcar.
Incorporating the teachings of the present disclosure, a railway car that meets applicable AAR limitations may be constructed with all vertical posts being properly aligned and capable of withstanding buff and draft forces experienced by the rail car during normal operation. According to one embodiment, railway car 20 may be a covered hopper car with approximately 7,000 cubic feet of capacity and RDL type gates for rapidly unloading its payload. It may be approximately seventy feet long by ten feet high. However, a variety of other suitable dimensions may be incorporated in accordance with the teachings of an embodiment of the present disclosure.
In contrast, a railway car using conventional construction techniques for a flat sided railway car with vertical posts may be approximately three inches narrower on each side of the car to be within applicable AAR clearance limitations for a constant width railway car which is approximately seventy feet long. Using the teachings of an embodiment of the present disclosure, including interior vertical posts, a seventy foot long railway car may allow recapture of two of the three inches lost using conventional techniques. Thus, each side of the railway car may recapture two inches of cargo carrying capacity along its entire length. These additional four inches may equate to approximately 230 cubic feet of additional capacity.
In general, as a railcar becomes longer as measured between its truck centers, its center width must become narrower. A railcar having a length of approximately 75 feet may require a center width approximately two feet narrower than the center width of a railcar having a length of approximately 42 feet. In some cases, such widths may be approximately 8 feet, 8 inches and 10 feet, 10 inches, respectively. As the length and amount of railcar that becomes narrower increases, the longer the car must become.
In addition to providing increased cargo carrying capacity due to the ability to provide a larger railway car having length 96 that is longer than conventional railway cars while remaining within applicable AAR clearance limitations, other advantages may be provided. For example, for a given required cargo capacity, a car may be constructed according to the teachings of an embodiment of the invention to have a length 96 that is shorter than a conventional length associated with railway cars having similar cargo capacity. A shorter car is generally more maneuverable and lighter than longer cars, and therefore, the ability to provide substantially the same cargo carrying capability with a shorter car is also advantageous. A shorter car may be constructed while maintaining substantially the same cargo carrying capacity because the teachings of the present invention allow increased width required by a shorter car to provide such capacity to fall within applicable AAR limitations.
Although the present invention has been described with reference to particular embodiments, it should be understood that various other changes, substitutions, and alterations may be made hereto without departing from the spirit and scope of the present invention. For example, the position and spacing of vertical side posts along the length of the railway car may be modified to fit a particular length or configuration of an associated railway car or manufacturing or other operational needs.
Numerous other changes, substitutions, variations, alterations, and modifications may be ascertained by those skilled in the art and it is intended that the present invention encompass all such changes, substitutions, variations, alterations, and modifications as falling within the spirit and scope of the appended claims.
This application claims priority to PCT Application No. PCT/US2009/037137 filed Mar. 13, 2009 which claims priority to U.S. Provisional Application No. 61/036,312 entitled “Increased Capacity Railcar and Method,” filed Mar. 13, 2008. The contents of this application is incorporated herein in its entirety by this reference.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/US09/37137 | 3/13/2009 | WO | 00 | 9/10/2010 |
Number | Date | Country | |
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61036312 | Mar 2008 | US |