Patent Application
20150014426
The present invention relates to a method and apparatus for protecting concrete rail beds of the type found in rail yards where rail locomotives are matched with rail cars to form trains. A rail yard, or railroad yard, is a complex series of railroad tracks for storing, sorting, or loading/unloading railroad cars and/or locomotives. Railroad yards have many tracks in parallel for keeping rolling stock stored off the mainline, so that they do not obstruct the flow of traffic. Railroad cars are moved around by specially designed yard switchers, a type of locomotive. Cars in a railroad yard may be sorted by numerous categories, including railroad company, loaded or unloaded, destination, car type, or whether they need repairs. In many cases rails in rail yards are not attached to laterally-extending sleepers, or ties, as is the case with rails that carry locomotives and attached cars between destinations. Rather, large concrete beds are formed onto which the rails are attached. A typical attachment method is to place a steel spacer plate at intervals along the bed onto which the rail is positioned and held in place with keeper wedges on both sides of the spacer plate. The spacer plate is bolted to the concrete bed with anchor wedges. Spacer plates are typically 6 to 10 inches long, a quarter to one-half inch thick and spaced approximately 3-5 feet apart. The rail is therefore spaced above the concrete bed by the thickness of the spacer plate. This has the further effect of concentrating the weight of the rails and of the locomotives and rolling stock onto relatively short segments of the concrete bed.
The concrete beds allow greater control of rail elevation, layout and similar factors not usually present on mainlines. The concrete beds also permit control of drainage of water, fuel and lubricants. These liquids are typically captured and disposed of in a manner required by regulation to prevent soil contamination and to minimize waste.
However, the manner in which rails are presently mounted on these concrete beds subjects these concrete beds to severe stresses. Whereas on mainline tracks the rails are under load for relatively short, intermittent periods of time, in rail yards extremely heavy locomotives and loaded cars may sit for hours or days in the same location. Locomotives with idling engines create vibrations that pass directly through the rails and into the concrete beds at the positions below the spacer plates. This causes crushing and eventual disintegration of the concrete. In cold climates water can enter the cracks and fissures caused by this disintegration and freeze, causing further damage as the expanding water opens the cracks and fissures further. Eventually, the concrete is subjected to greater vibration as the spacer plate wallows in an area of disintegrated concrete.
It has long been recognized in the prior art that on mainline railway tracks cushioning of the rails on sleepers has the desirable effect of damping the intervals of compression as the steel wheels of locomotives and rolling stock passes at speed along the rails. However, it has not been recognized that cushioning of rails in railway yards, where locomotives and rolling stock are generally stationary or moving very slowly would also be beneficial.
Therefore, it is an object of the invention to provide an apparatus for cushioning rails on a continuous concrete railway bed such as found in rail yards.
It is a further object of the invention to provide a method of preventing crushing and disintegration of continuous concrete railroad beds resulting from long term vibration and weight application.
These and other objects and advantages of the invention are achieved by providing an apparatus for protecting a continuous concrete rail bed, comprising a resilient, compressible cushion for being placed directly upon the continuous concrete rail bed and a spacer plate for being positioned onto the cushion. The cushion and spacer plate are sized and shaped to extend laterally outward in opposing directions beyond the width of the opposing flanges of a rail positioned on the spacer plate to define first and second attachment areas on opposite sides of the rail. First and second locks are provided for being positioned on a top surface of the spacer plate at the first and second attachment areas and engaging the opposing flanges of the rail for locking the rail in position on the spacer plate. First and second anchors are provided for anchoring the cushion, spacer plate and lock to the concrete bed at the respective first and second attachment areas of the spacer plate.
According to one embodiment of the invention, the first and second locks each comprise a keeper wedge having an inwardly extending shoulder for residing against a top surface of the flange of the rail.
According to another embodiment of the invention, the cushion, spacer plate and lock each include aligned through bores for receiving an anchor wedge mounted in and extending upwardly from the concrete bed.
According to another embodiment of the invention, the cushion comprises a sheet of styrene-butadiene rubber (SBR)/synthetic fabric belting material.
According to another embodiment of the invention, the cushion comprises a sheet of recycled rubber tire underlayment material.
According to another embodiment of the invention, the cushion comprises a sheet of compressed non-asbestos sheet material that includes aramid fiber.
According to another embodiment of the invention, the cushion comprises a sprayed-on polyurea applied to the bottom of the spacer plate.
According to another embodiment of the invention, the cushion and the spacer plates have approximately the same width and length dimensions.
According to another embodiment of the invention, an apparatus is provided for protecting a continuous concrete rail bed, comprising a resilient, compressible cushion for being placed directly upon the continuous concrete rail bed and a spacer plate for being positioned onto the cushion. The cushion and spacer plate have approximately the same width and length dimensions and are sized and shaped to extend laterally outward in opposing directions beyond the width of the opposing flanges of a rail positioned on the spacer plate to define first and second attachment areas on opposite sides of the rail. First and second locks are provided for being positioned on a top surface of the spacer plate at the first and second attachment areas and engaging the opposing flanges of the rail for locking the rail in position on the spacer plate. The first and second locks each comprise a keeper wedge having an inwardly extending shoulder for residing against a top surface of the flange of the rail. First and second anchor wedges are embedded in the concrete bed and extend upwardly through aligned bores in the cushion, spacer plate and locks for anchoring the cushion, spacer plate and lock to the concrete bed at the respective first and second attachment areas of the spacer plate.
According to another embodiment of the invention, a method of protecting a continuous concrete rail bed is provided, and includes the steps of determining an appropriate spacing along the length of a continuous concrete rail bed for placing a plurality of apparati for protecting the concrete rail bed. The method also provides a resilient, compressible cushion for being placed directly upon the continuous concrete rail bed with a spacer plate positioned onto the cushion. The cushion and spacer plate are sized and shaped to extend laterally outward in opposing directions beyond the width of the opposing flanges of a rail positioned on the spacer plate to define first and second attachment areas on opposite sides of the rail. First and second locks are provided for being positioned on a top surface of the spacer plate at the first and second attachment areas and engaging the opposing flanges of the rail for locking the rail in position on the spacer plate, and first and second anchors are provided for anchoring the cushion, spacer plate and lock to the concrete bed at the respective first and second attachment areas of the spacer plate. The first and second anchors are embedded in the concrete rail bed on opposite sides of a space to be occupied by a length of rail, and a cushion is positioned onto the concrete rail bed. A spacer plate is positioned onto the top of the cushion and a lock is placed onto the top of the spacer plate. The lock, spacer plate and cushion are anchored to the concrete rail bed with the first and second anchors, and the rail is positioned onto the top of the spacer plate between the first and second anchors. The rail is locked to the spacer plate with the locks. The method is repeated at the appropriate spacing along the length of the concrete rail bed.
According to another embodiment of the invention, the step of positioning a cushion onto the concrete rail bed comprises the step of positioning a material selected from the group consisting of a sheet of styrene-butadiene rubber (SBR)/synthetic fabric belting material, a sheet of recycled rubber tire underlayment material, a sheet of compressed non-asbestos sheet material that includes aramid fiber and a sprayed-on polyurea applied to the bottom of the spacer plate.
According to another embodiment of the invention, the first and second locks comprise first and second keeper wedges, each having an inwardly-extending shoulder for being positioned over respective flanges of the rail.
According to another embodiment of the invention, the method includes steps of forming aligned through bores in the cushion, spacer plate and lock for receiving an anchor wedge mounted in and extending upwardly from the concrete bed.
The present invention is best understood when the following detailed description of the invention is read with reference to the accompanying drawings, in which:
Referring now specifically to the drawings,
Referring now to
As shown in
Similar cushions 32 and spacer plates 34 are positioned at intervals along the path of the railway and a rail “R” is positioned onto the spacer plates 34 with a section of the each cushion 32 and spacer plate 34 exposed on opposite sides of the rail “R”. See
Styrene-butadiene rubber (SBR)/synthetic fabric belting material, 2 Ply 220 Black 3/16× 1/16″ (total thickness ¼″) such as manufactured by Beltservice Corporation.
Recycled rubber tire underlayment material, such as manufactured by Ecore International, ¼″ (specified as 6 mm) thick. This porous product is most suitable for warm climates where freezing of water in the porosities of the material is not a concern.
Compressed non-asbestos sheet material, such as manufactured by Texcel Rubber, ⅛″ thick, Part No. SEAL-G-4. This material is fabricated of aramid fiber, inorganic fiber and a nitrile binder.
Sprayed-on polyurea applied to the bottom of the spacer plate 34 at a thickness of 1/16″.
These materials absorb vibration and continuous compression caused by locomotives and rolling stock, particularly vibration caused by stationary, idling locomotives. The material of Example 1 is considered the preferable material based on cost, ease of application and wear longevity.
A method and apparatus for protecting concrete rail beds according to the invention have been described with reference to specific embodiments and examples. Various details of the invention may be changed without departing from the scope of the invention. Furthermore, the foregoing description of the preferred embodiments of the invention and best mode for practicing the invention are provided for the purpose of illustration only and not for the purpose of limitation, the invention being defined by the claims.
