Patent Application
20170217450
The present application claims the benefit of U.S. Provisional Patent Application Ser. No. 62/297,944 filed Jan. 28, 2016 entitled “Coil Railcar with Floating Floor.”
The present invention relates to coil railcars with features accommodating thermal expansion.
Freight railroad cars are critical to the economic well-being and global competitiveness of any industrialized country. For example, freight railroad cars move an estimated 42 percent of the United State's freight (measured in ton-miles) more than any other mode of transportation. Essentially all goods are shipped by rail—everything from lumber to vegetables, coal to orange juice, grain to automobiles, and chemicals to scrap iron. Freight carrying railcars connect businesses with each other across most countries and connect business within such countries with outside markets.
Rail provides major advantages in energy efficiency over other modes. On average, railroads are three times more fuel efficient than road transportation, e.g., trucks. Railroads are environmentally friendly as the U.S. Environmental Protection Agency (EPA) estimates that for every ton-mile, a typical automotive truck emits roughly three times more nitrogen oxides and particulates than a locomotive. Other studies suggest trucks emit six to 12 times more pollutants per ton-mile than do railroads, depending on the pollutant measured. Railroads have a clear advantage in terms of greenhouse gas emissions. According to the Environmental Protection Agency (EPA), railroads account for just 9 percent of total transportation-related NOx emissions and 4 percent of transportation-related particulate emissions, even though they account for 42 percent of the nation's intercity freight ton-miles.
Further, freight railroads significantly alleviate highway congestion. A single intermodal train takes up to 280 trucks (equivalent to more than 1,100 cars) off associated highways; a train carrying other types of freight takes up to 500 trucks off the associated highways. It has been noted that overcrowded highways act as an “inefficiency tax” on our economy, seriously constraining economic growth. Freight railroads help relieve this restriction by reducing gridlock, enhancing mobility, and reducing the pressure to build costly new highways.
Finally, railroads have major safety advantages over other modes. For example, railroads are the safest way to transport hazardous materials. In the United States, railroads and trucks carry roughly equal hazmat ton-mileage, but trucks have nearly 16 times more hazmat releases than railroads. Thus there is a need to continue to improve and revitalize the freight car industry.
Focusing on improving the manufacturing process and car design and assembly can decrease associated costs and assembly time. It has been reported by the Highland Group that the implementation of lean manufacturing techniques and just in time inventory procedures to a railcar fabrication center was able to increase production at the facility of about 50%. This increase in efficiency can be further enhanced or supplemented with improved product design that attempt to maximize efficiency without altering railcar capacity or operation.
Coil cars are a specialized type of railcars, or rolling stock designed primarily for the transport of coils (i.e., rolls) of sheet metal, most commonly steel coils. For an overview of all freight car developments within the United States and associated industry trends see United States International Trade Commission 2011 report on Rolling Stock: Locomotives and Rail Cars (see http://www.usitc.gov/pubicatons/332/ITS-08.pdf). Coil cars are often are considered a subtype of the gondola car, though coil cars bear little resemblance to a typical gondola. A gondola is generally an open-top type of rolling stock that is typically used for carrying loose bulk materials, while coil cars carry items such as plates or coils, or bulky items such as prefabricated pieces of rail track.
Prior to the development, and wide adoption, of coil cars, coils of sheet steel were carried on end or in cradles in open or covered gondolas. Load shifting, damage, and awkward loading and unloading were all problems with this type of loading, and since so much sheet steel is transported, a specialized car was designed for this use.
The body of a coil car consists of at least one trough, or a series of troughs, and may be lined with wood or other material to cushion the carried coils. The coils are set on their sides and supported by the sides forming the trough, and stops may be applied to keep the coils from shifting. Often the trough or pair of troughs are positioned longitudinal relative to the railcar as shown, for example, in U.S. Pat. Nos. 4,451,188 and 6,543,368, which are incorporated herein by reference.
The longitudinal placement of the troughs in a coil car can mean that the coils can be shifted in the trough due to the acceleration and deceleration and impact forces exerted due to the car motion along the track. Thus, in some instances, the coils are carried with their axes transverse to the direction of travel of the car. Representative examples of this construction include U.S. Pat. No. 1,850,597; U.S. Pat. No. 3,291,073 showing a coil skid design; U.S. Pat. No. 3,693,554 discloses a rail flat car with a plurality of transverse bulkheads; and U.S. Pat. No. 3,715,993 in which the cylindrical objects are cable reels. These patents are also incorporated herein by reference. Transverse coil cars typically have a number of parallel troughs, rather than one or two long trough(s). Each trough is generally V-shaped, and the coil sits in the transverse trough with the outer circumference of the coil tangent to the V at two points such that it cannot roll. The V-shaped troughs are generally lined, such as with wood decking to act as cushioning, thereby discouraging damage to the coils during loading or travel.
Applicant's U.S. Pat. No. 9,387,864 discloses a transverse trough coil car with improved trough construction, and is incorporated herein by reference (see also Publication number 2015-0083020 which is incorporated herein by reference).
U.S. Pat. No. 2,810,602 discloses a trailer vehicle body which includes transverse laden supports and is also of general interest to the present invention.
One difficulty with the illustrated construction of
There remains a need in the industry to provide car designers with modular assemblies allowing new car designs to be easily implemented saving both design and manufacturing time and money.
The present invention is directed to a transverse trough coil car which includes a plurality of transverse troughs along the car body. The car includes a pair of trucks, a center sill supported on the trucks and extending substantially the longitudinal length of the car, a pair of side walls extending the longitudinal length of the car on opposed sides of the car and coupled to the center sill, each side wall including a side sill, top chord and side plate extending between the top chord and the side sill, and a plurality of trough forming assemblies, with each trough forming assembly including at least one floating floor sheet.
Floating with regard to the floor sheets of the present invention mean that the floor sheet is coupled to the associated structure in a manner so as to accommodate thermal expansion in a length and width direction of the floor sheet.
These and other advantages of the present invention will be described in connection with that attached figures in which like reference numeral represent like elements throughout.
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 an apparatus according to the preferred embodiment of the present invention and in which:
A truck 14 (also known as bogies), in railroading, references the railroad car wheel assembly usually having two or more axels and which typically rotate freely beneath the cars in order to allow the cars to navigate turns.
The center sill 22 is generally a box shaped in cross-section and may be considered the main structural member of the railcar. The center sill 22 runs from one end coupling 24 (also known as couplers) of the car to the other. The center sill 22 is the primary load path of the car both for longitudinal buff and draft loads from coupler to coupler, and for carrying the vertical load bending moment between the trucks. See examples in U.S. Pat. Nos. 7,861,659; 6,119,345; 5,860,366; 4,565,135; 4,493,266 and 4,194,451 which are incorporated herein by reference.
The transverse trough coil railcar body 20 includes a pair of side walls 26 extending the longitudinal length of the car body 20 on opposed sides of the car, each side wall 26 including a side sill 28, top chord 30, and side plates extending between the top chord 30 and the side sill 28. Side stakes 34 may be provided to further support the side plates.
The side plates may be formed of a number of distinct plate members as needed. The construction of the side walls 26 is generally known in the art as is the end construction and intermediate cross supports (not shown) coupling the side sills 28 of the side walls 26 to the center sill 22. The top chords 30 and side sills 28 may be open or closed structural members and may be formed as composite members as known in the art.
A significant aspect of the present invention is the inclusion of a plurality of trough forming assemblies 40, including the end trough forming assemblies 40′, each including floating floor sheets 42 in accordance with one aspect of the present invention. The trough forming assembly 40 is shown in detail individually in
The trough forming assembly 40 may be considered modular trough forming assemblies 40, analogous to that described in U.S. Pat. No. 9,387,864, allowing for reducing the fabrication costs, inventory costs and assembly time for each distinct car design. The modular trough forming assemblies 40 can be used to form essentially any desired number transverse troughs appropriate for the car. Increasing or decreasing the lateral distance between adjacent trough forming assemblies 40 creates larger or smaller pockets there between without requiring specialized components or requiring customized parts. A pair of adjacent trough forming assemblies 40 (or a trough forming assembly 40 and an end trough forming assembly 40′) forms a pocket or trough.
Each trough forming assembly 40, shown in
The floating floor sheets 42 are coupled to trough forming assembly 40 in a manner to allow for thermal expansion in the length and width direction of the floor sheet 42 as noted above, floating with regard to the floor sheets 42 of the present invention define that the floor sheet 42 is coupled to the associated structure in a manner so as to accommodate thermal expansion in a length and width direction of the floor sheet 42. The floor sheets 42 may be effectively formed from ASTM A-572 Grade 60 for most coil car applications. For example the floor sheet 42 may be supported on the base member 52 via a series of angles or stops 66 welded to the sheet 42 in a manner (between plates 60 and supports 56) to allow expansion of the sheet 42 as needed. Expansion room under the ridge member 54 allows for expansion in this direction, and the ridge member 54 retaining the floor sheet. The outermost frame members 56 engage with floor sheet clips 62 that are welded to the floor sheet 42 to support and retain the floating floor sheets 42 in a manner allowing side to side expansion. In other words the clips 62 secure the floor sheets 42 but allow expansion side to side (as does the resting stops 66). The floor sheets 42 are thus floating on the trough forming assembly 40
One end trough forming assembly 40′ is shown in detail individually in
The design of the trough forming assemblies 40, in particular, and the bolting of the frame to the sidewall 26 to a lesser extent, allows for a distinct car to be easily converted in use to alternative trough configurations to accommodate other designated uses without substantial retrofitting of the car design.
The transverse trough coil car body 20 according to the present invention may further include floating trough floor pans extending between adjacent trough forming assemblies to complete the trough sections.
The troughs may include other coil engaging structure (not shown) such as wood supports to protect the coils and car cover structures over the car body, which also protect the coils.
A key feature of the present invention is the provision of a plurality of trough forming assemblies 40 and 40′, with each trough forming assembly 40 and 40′ including at least one floating floor sheet 42. Again, floating with regard to the floor sheets 42 of the present invention defines that the floor sheet 42 is coupled to the associated structure in a manner so as to accommodate thermal expansion in a length and width direction of the floor sheet 42. This design allows for the floor sheets 42 of the railcar to expand and contract as needed due to the thermal input associated with the loading and unloading of hot coils. By allowing the floor sheets 42 to free float as described the floor sheet thickness may be optimized and ⅜″ plate may be effectively used. The design reduced stress concentrations due to thermal expansion and contraction and the premature fatigue that can occur with repeated cyclic loading of this type. These stresses can be evidenced in car as a whole and the present design is believed to increase the longevity of the trough and the car as a whole.
A preferred embodiment has been described in detail and a number of alternatives have been considered. As changes in or additions to the above described embodiments may be made without departing from the nature, spirit or scope of the invention, the invention is not to be limited by or to those details, but only by the appended claims and equivalents thereto.
| Number | Date | Country | |
|---|---|---|---|
| 62287944 | Jan 2016 | US |
