Adjustable Skirt Volume for Railroad Freight Car Lading
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Flow through railroad freight cars face challenges in optimizing their internal volume to match the density of the cargo without exceeding the permissible gross rail load, as higher density lading can fill the car beyond safe limits, necessitating a solution to adjust the volumetric capacity effectively.
Innovation Solution
The design incorporates a containment shell with a variable-length, partially removable depending skirt that adjusts the internal volume by changing the skirt's length or replacing it with a different one, allowing for precise adjustment of the volumetric fill capacity based on the lading density, and includes features like a protective epoxy coating and inert materials to prevent contamination.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of stationary object
If the internal volume of the railroad car is increased to match higher density lading, then the volumetric capacity is improved, but the car may exceed the permissible gross rail load
Solution Approach 1:
The patent applies the dynamics principle by making the depending skirt removable and replaceable with skirts of different lengths. This allows the internal volume of the containment shell to be dynamically adjusted based on the density of the lading being transported. When transporting higher density materials, a shorter skirt is installed to reduce volume and prevent exceeding gross rail load limits. When transporting lower density materials, a longer skirt or full-length skirt is used to maximize volumetric capacity. This dynamic adjustment resolves the contradiction between maximizing volume and maintaining weight limits.
2Weight of moving object
If the depending skirt length is increased to reduce internal volume, then the gross rail load is controlled, but the volumetric capacity for lower density lading is reduced
Solution Approach 1:
The depending skirt is designed as a removable component that can be replaced with different length variants. This dynamic configuration allows the railroad car to optimize its internal volume for each specific lading type. For low-density materials like grain or pellets, a longer skirt provides maximum volumetric capacity. For high-density materials like ore or aggregate, a shorter skirt reduces volume to stay within gross rail load limits. This resolves the contradiction by making volume adjustable rather than fixed.
Solution Approach 2:
The patent changes the physical parameter of the depending skirt length to adjust the internal volume of the containment shell. By available different skirt lengths (e.g., full-length, partial-length, or removable), the system can change its volumetric capacity parameter to match the density characteristics of different lading types. This parameter change approach allows the same railroad car body to safely transport various materials with different densities without exceeding weight limits or leaving unused capacity.
3Adaptability or versatility
If the depending skirt is made removable and replaceable, then the adaptability to different lading densities is improved, but the device complexity increases
Solution Approach 1:
The depending skirt is segmented as a separate, removable component from the containment shell structure. This segmentation allows the skirt to be independently installed or removed without affecting the main car body or other components. The simple modular design—where the skirt is essentially a standalone cylindrical or conical section that fits into the inlet opening—minimizes the complexity of the replacement process. Workers can remove and install different length skirts using basic tools, making the adaptability feature practical despite the added component.
4Productivity
If the nominal capacity of the railroad car is maintained at high levels, then the productivity is improved, but the risk of exceeding permissible gross rail load increases
Solution Approach 1:
The patent changes the effective capacity parameter of the railroad car by adjusting the depending skirt length. The nominal capacity of the car body remains high, but the actual usable volume is controlled by the skirt configuration. For example, a car with a 4500+ cubic foot body can effectively reduce its capacity to match specific lading densities by installing appropriate skirt lengths. This ensures that the car can consistently operate at or near its maximum safe payload without exceeding gross rail load limits, thereby maintaining both high productivity and reliability.
Data Source
AI summary
A flow through railroad freight car may include a body having a containment structure. The body may be mounted upon railcar trucks for rolling motion along railroad car tracks. The containment structure may include one or more hoppers, each of which may have inflow and outflow ports, by which means lading may be introduced into the car, or discharged from it. The inflows may include an upper intake, which may be a series of hatches and hatch coamings. The hatch coamings may stand outwardly from the containment structure, and may also having internally extending skirts. In one instance, the skirts may be of a first length corresponding to a first fill level, or volume, for use with lading of a first density. The length of the skirt may be adjusted at a later time to correspond to a second fill level, or volume, for use with lading of a second density.