Railroads have long been a staple mode of transportation for goods and persons. Railroads consist of a pair of rails laid on a plurality of support beams known as railway ties. Railway ties (also referred to as a railway “sleeper”) lie on/in a ballast supported by the ground. Each rail is secured to the railway tie via one or more rail fastening system. Railway fastening systems include a baseplate is secured to the railway tie, and the rail is affixed to the baseplate via one or more railway fasteners. Various types of fastening systems are known in the art, such as rail spike/baseplate above the tie combinations, baseplates with multi-gauge tracks, track joints and chairs including fishplate spanning ties, Pandrol “e-Clip” fastening components, Pandrol “fastclip” fastener systems, tension clamp fastening, bolt clamped fastening, steel spring keyed rail in chair systems, etc.
Railway ties may take a variety of shapes and forms, including standard crossties, Y-shaped ties, twin ties, wide ties, bi-block ties, frame ties, and ladder track. Railway ties have been made from wood, steel, concrete, stone block, rubber, and various plastics.
The present embodiments include a composite railway tie that provides distinct advantages over prior railway tie systems. The railway tie includes at least one insert located at the rail fastening interface. The present embodiments acknowledge disadvantages of prior art railway ties in that non-composite materials such as wood, steel, concrete and stone are too heavy and suffer from weather degradation, water rot, and insect rot. Moreover, the present embodiments, particularly the insert allows for flexibility in manufacturing, while at the same time providing support required to support the rails, as well as the spike pull-out force requirements according to the American Railway Engineering and Maintenance-of-Way Association (AREMA) standard.
Railway tie 100 includes an outer shell 102 having a length, width, and height characteristic as indicated by axes L, W, H, respectively. The length, width, and height vary based on application of use of the railway tie 100. For example, AREMA standards specify ties of cross section dimensions 7″×9″, with lengths varying from 108″ for standard applications up to 240″ for specialty switches and junction applications. Further, “half height” tie products designed for tunnel applications can also be designed with cross section dimensions 3.625″×9.375″, again with lengths varying from 108″ for standard applications up to 240″ for specialty switches and junction applications. In the figures, the length is greater than the width and height, and the width is greater than the height. However, other dimensions of length, width, and height may be used without departing from the scope hereof and depending on the application.
The inside of outer shell 102 is hollow such that an inner surface 202 of outer shell 102 creates a hollow shell void 204. At least one fastener insert 206 is located in the shell void 204. Two fastener inserts 206(1) and 206(2) are shown for example purposes only. There may be more or fewer fastener inserts 206 without departing from the scope hereof. For example, the fastener inserts 206 may comprise a plurality of fastener inserts spaced such that a first of the plurality of inserts (or a first set of the plurality of inserts) align with a first rail of a railway and a second of the plurality of inserts (or a second set of the plurality of inserts) aligns with a second railway of the railway when the railway tie is installed under the first and second rails. A load bearing insert 208 is shown located between first fastener insert 206(1) and 206(2). Load bearing insert 208 serves to provide support from the loads applied to the railway tie 100 when in use. As shown in
Insert 206 includes an insert void 506 (shown in
Although only one conduit component 504 is shown, it should be appreciated that there may be more conduit components within a single insert 206, or multiple inserts within the same outer shell, to align an individual fastener hole of a baseplate with a given conduit (see e.g.,
As shown in
As shown in
The hollow shell 102 may be coated with a UV-resistant material. In embodiments, the coating is a urethane-based UV coating. This UV protective layer may be applied via chemical or adhesive bonding to the surface of the part, painting, powder coating, nano ceramic coating, or any other suitable coating method. The UV protective layer may also consist of a physical sleeve or protective barrier around the surface of the part.
In at least some embodiments, the hollow shell 102 is made of a first material, the insert-shell component 502 is made of a second material, and the conduit component 504 is made of a third material. In one particular embodiment, the first and second material are the same, and the third material is different from the first and second material. For example, the first and second material may be plastic, pultruded plastic, fiberglass, and/or pultruded fiberglass, and the third material may be metal, such as but not limited to steel. This combination of materials provides a particular advantage of reducing weight by using plastic and/or fiberglass (pultruded or not), having reduced thickness thereof via the load-support provided by the fastener inserts 206 and optionally load-bearing insert 208, as well as achieving the fastener pull-out requirements such as those defined in the AREMA standard as discussed below.
First side 402 has a first thickness 410TS1 defined between first-side inner surface 402Si and first-side outer surface 402So. Second side 404 has a second thickness 412TS2 defined between second-side inner surface 404Si and second-side outer surface 404So. Third side 406 has a third thickness 414TS3 defined between third-side inner surface 406Si and third-side outer surface 406So. Fourth side 408 has a fourth thickness 416TS4 defined between fourth-side inner surface 408Si and fourth-side outer surface 408So. First thickness 410TS1, second thickness 412TS2, third thickness 414TS3, and fourth thickness 416TS4 may have the same or differing thicknesses. For example, in
The outer shell 102 is defined by dimensions of an outer height 418Hs,o, an inner height 420Hv,i, an outer width 422Ws,o, an inner width 424Wv,i, The outer height 418Hs,o is defined between first outer surface 402So and second outer surface 404So. The inner height 420Hv,i, is defined between first inner surface 402Si and second inner surface 404Si. The outer width 422Ws,o is defined between third outer surface 406So and fourth outer surface 408So. The inner width 424Wv,i is defined between third inner surface 406Si and fourth inner surface 408Si. Thus, it should be appreciated that the inner surfaces 402Si, 404Si, 406Si, and 408Si define the shell void 202, and the shell void 202 has dimensions the same as inner height 420Hv, and inner width inner height 422Wv,i.
The fastener insert 206 is defined by dimensions of an insert height 426HI, an outer width 428WI,o, and an inner width 430WI,i. Similar dimensions may apply to the load-bearing insert 208. The conduit component 504 is defined by dimensions of a conduit height 432HC, an outer width 434WC,o, and an inner width 434WC,i. In embodiments, the insert 206 spans from first side 402 to the second side of the outer shell 102. Specifically, the insert 206 may span from the first-side inner surface 402Si to the second-side inner surface 404Si. Accordingly, the insert height 426HI and the inner height 4420Hv of the shell void 202 may be substantially the same (e.g., a clearance less than 0.5 mm, less than 0.75 mm, less than 1 mm, or less than 2 mm). In one specific embodiment, the clearance is 0.76 mm. This provides the advantage of reinforcing the outer shell 102 against force applied to one or both of the first side 402 and the second side 404. Similarly, the insert height 426HI, the conduit height 432HC and the inner height 420Hv of the shell void 202 may be substantially the same (e.g., a clearance less than 0.5 mm, less than 0.75 mm, less than 1 mm, or less than 2 mm). In one specific embodiment, the clearance is 0.76 mm.
As shown in
In embodiments, the first outer-shell hole 438 and the second outer-shell hole 440 are filled with one or more plugs 444. Plugs 444 may be an integral component of outer shell 102, that is a “knockout” plug. The knockout plug may be a separate component that is snap-fit within the first outer-shell hole 438 and the second outer-shell hole 440. In another embodiment, the knockout plug may be characterized by a groove cut, etched, or otherwise formed in the outer shell 102 at the location of the (i.e., the plug may be a weakened portion of the outer shell 102 via removing a portion of the first outer-shell hole 438 and the second outer-shell hole 440 that allows the material of the outer shell 102 to be removed when installing the rail baseplate and/or fastener.
A baseplate 602 is positioned above the inserts 604 such that a baseplate aperture 610(1), 610(2) align with corresponding shell holes 612(1), 612(2). Shell holes 612(1) and 612(2) are an application of shell holes 438, 440 discussed above, and therefore all discussion of shell holes 438, 440 discussed above applies to shell holes 612 as well. Although only two baseplate apertures 610 and two shell holes 612 are shown, there may be more or fewer without departing from the scope hereof.
Rail 612 is secured in a groove of baseplate 608 defined by protrusions 614 extending upward from the flange of baseplate 608, where the baseplate apertures 610 are defined in the flange. A clamp component 616 is secured in place via rail fasteners 618(1), 618(2) to secure the rail to the baseplate 608, and thus to rail tie 602. In embodiments, the fastener 618 directly secures the rail 612 to the baseplate 608.
Two fastener inserts 604 are shown for a single baseplate in
Referring to
In block 702, an outer shell of the railway tie is formed. In one example of block 702, outer shell 102 is formed. If outer shell 102 is a pultruded product, then outer shell 102 may be formed by pultruding the material and cutting at a desired length. Where outer shell 102 includes one or more shell holes such as shell holes 438, 440 discussed above, block 702 may include forming the shell holes. Where the shell holes 438 include a plug, such as plug 444 discussed above, block 702 may include creating or inserting plug into the formed shell holes.
In block 704, at least one fastener insert is formed and inserted into the outer shell formed in block 702. In one example of block 704, the fastener insert 206 is formed including an insert-shell component 502, and a conduit component 504. The conduit component may be located in an insert-shell void 506. The insert shell void 506 may be filled with an insert material, or otherwise the same material as the insert-shell component 502. After forming the fastener insert 206, it is located within the void of outer shell 102 formed in block 702 and aligned where the rail is to be installed (e.g., the conduit is aligned with the shell hole in the outer shell 102). In embodiments, inserting the insert includes a first insert and a second insert, the first insert spaced from the second insert according to a standard rail spacing distance of a railway.
In block 706, at least one load bearing insert is formed and inserted into the outer shell formed in block 702. In one example of block 706, the load bearing insert 208 is formed including an insert-shell component 502 and optionally an insert material. The conduit component may be located in an insert-shell void 506. The insert shell void 506 may be filled with an insert material, or otherwise the same material as the insert-shell component 502.
In block 708, the void is filled with a void material after insertion of the inserts in blocks 704, 706. In one example of block 708, the void 202 is filled with void material 306 to secure the inserts in place within void 202. In an embodiment, the insert-shell material 206 and the void material 306 are both provided at the same time, after the insert shell component 502 and conduit component 504 is positioned with respect to the railway tie. In such embodiments, any of the inserts discussed herein (e.g., fastener inserts 206 and/or load bearing inserts 208) may have one or more notches on the top and/or bottom ends thereof, or with one or more holes going through the sides of the insert shell component 502 such that expandable foam injected into the void can also enter into the insert void when the insert is already located in the railway tie. In block 710, an endcap is placed on each end of the outer shell to seal the outer shell. In one example of block 710, the endcap 104 is secured on each end of outer shell 102.
In block 712, the rail tie 100 is coated with a UV resistant material. Block 712 may be performed during any of the previous blocks, or post-generation of the outer shell with insert therein.
The above-described systems and methods provide significant advantages over prior rail tie systems, including prior composite rail tie systems. The inclusion of the insert, whether fastener insert allows for significant flexibility in the type of rail tie fastening system by allowing for simple adaptation based on location of the fastener insert. Moreover, the location of the fastener insert, and optional load-bearing insert, allows for the thickness of the outer shell to be reduced resulting in less weight/material required for the railway tie. The void material, and optional end caps, allow for improved water/insect protection by not providing a place for water/insect/rodent intrusion.
Another major advantage provided by the present embodiments is the ability to accommodate the spike pull-out force requirements of the AREMA standard as well as the total beam deflection requirements required by AREMA (e.g., AMERICAN RAILWAY ENGINEERING AND MAINTENANCE-OF-WAY ASSOCIATION (AREMA), Manual for Railway Engineering, Chapter 30, Section 2.3 Test 2 (deflection criteria found in Table 30-5-1)). Table 1, below shows test results for Total Beam Deflection, in inches, as well as permanent deformation of outer shell holes in three samples. The materials for the outer shell included fiber reinforced polymer filled with a fiber reinforced polymer insert, where each of the outer shell and insert were filled with expanding closed cell foam. The size of the outer shell conformed to the above-discussed “half height” tie products (e.g., with cross section dimensions 3.625″×9.375″). The deflection values below were recorded during and after the sample was subjected to 50,000 lbs. of load. The compression area plate included a 3.75 inch by 14 inch by 1 inch pressure applied to a foam-filled outer shell embodying rail tie 100 discussed above.
Table 2, below, establishes that the rail spike-pull out force required by AREMA standard is met via railway tie 100 discussed above. To implement the test to generate table 2, rail spikes were driven into predrilled holes (e.g., shell holes discussed above) in an outer shell with a bushing therein, and additionally with foam-filled insert having a steel conduit therein such as the inserts 206 discussed above. The materials for the outer shell included fiber reinforced polymer filled with a fiber reinforced polymer insert, where each of the outer shell and insert were filled with expanding closed cell foam. The size of the outer shell conformed to the above-discussed “half height” tie products (e.g., with cross section dimensions 3.625″×9.375″). As shown in Table 2, the first test included an “as-is” predrilled railway tie with a reinforcing bushing of foam-filled insert. This did not meet the required pull-out forces for the AREMA standard (e.g., 1900 lbs.). However, after iterating the hole size and adding the conduit component, sufficient pull-out force threshold was met thereby meeting the AREMA standard. It is expected that alternate insert materials, or homogeneous inserts would be able to achieve sufficient pull out force.
The above-test results establish that the railway tie 100 (and that used in system 600), as manufactured using method 700, meet the requirements of the AREMA standard. This, in combination with the weight reduction and weather and insect/rodent prevention.
The above-described embodiments may be combined in numerous ways as understood by those of skill in the art. The following list of combination of features is not exhaustive, and any of the above-described features may be combined with any of the below embodiments and aspects.
(A1) In a first embodiment of a first aspect, railway tie, comprises an outer shell having an inner surface defining a shell void in the outer shell.
(A2) In the above embodiment described in (A1), a void material may fill the shell void.
(A3) In either above embodiment described in (A1) or (A2), an insert may be located in the shell void that spans from a first side of the outer shell to a second side of the outer shell and reinforces the outer shell against force applied to one or both of the first side and the second side.
(A4) In any above embodiment described in (A1)-(A3), the insert includes an insert-shell component.
(A5) In any above embodiment described in (A1)-(A4), the insert includes a conduit component located in the insert-shell component, the conduit component sized and shaped to receive a railway fastener.
(A6) In any above embodiment described in (A5), the conduit component includes a flange on each end thereof.
(A7) In any above embodiment described in (A3)-(A6), the insert-shell component is a pultruded beam cutaway.
(A8) In any above embodiment described in (A4)-(A7), the insert-shell component includes an insert void, the insert void being filled with an insert material.
(A9) In any above embodiment described in (A8), the insert material is foam.
(A10) In any above embodiment described in (A5)-(A9), the conduit component defines a pre-formed insert hole sized and shaped to receive the railway fastener.
(A11) In any above embodiment described in (A10), the outer shell defines a first outer shell hole on the first side; wherein when the insert is mounted in the shell void, the pre-formed insert hole and the first outer shell hole are aligned.
(A12) In any above embodiment described in (A10)-(A11), further comprising the railway fastener located in the pre-formed insert hole and the first outer shell hole.
(A13) In any above embodiment described in (A1)-(A12), the conduit component comprises a plurality of conduit components, each positioned according to a respective location of a baseplate aperture of a plurality of baseplate apertures defined by a baseplate that is used to secure a rail to the railway tie.
(A14) In any above embodiment described in (A1)-(A13), the conduit component is a different material than the insert-shell component.
(A15) In any above embodiment described in (A1)-(A14), the conduit component is a steel material.
(A16) In any above embodiment described in (A1)-(A15), the fastener insert comprises a plurality of fastener inserts spaced such that a first of the plurality of inserts align with a first rail of a railway and a second of the plurality of inserts aligns with a second railway of the railway when the railway tie is installed under the first and second rails.
(A17) In any above embodiment described in (A1)-(A16), the insert comprises a plurality of inserts spaced such that each conduit of one of the insert is positioned according to a respective location of baseplate aperture of a plurality of baseplate apertures defined by a baseplate that is used to secure a rail to the railway tie.
(A18) In any above embodiment described in (A1)-(A17), the outer shell comprises fiberglass.
(A19) In any above embodiment described in (A1)-(A18), further comprising an endcap at each end of the railway tie.
(A20) In any above embodiment described in (A1)-(A19), the insert and outer shell characterized to provide a spike pull-out force threshold greater than 1900 pounds, measured according to AMERICAN RAILWAY ENGINEERING AND MAINTENANCE-OF-WAY ASSOCIATION (AREMA) standard.
(A21) In any above embodiment described in (A1)-(A20), the outer shell being coated with a UV resistant coating.
(B1) In a first embodiment of a second aspect, a method for manufacturing a railway tie includes forming an outer shell having an inner surface defining a shell void in the outer shell.
(B2) In the above embodiment described in (B1), the method further includes inserting a fastener insert that spans from a first side of the outer shell to a second side of the outer shell and reinforces the outer shell against force applied to one or both of the first side and the second side.
(B3) In either above embodiment described in (B1) or (B2), the method further includes after inserting the insert, filling the void with an insert material.
(B4) In any above embodiment described in (B1)-(B3), the method further comprises securing an endcap on each end of the outer shell.
(B5) In any above embodiment described in (B1)-(B4), the method further comprises forming a first outer shell hole; and wherein the inserting the insert includes aligning an insert hole defined by the insert with the first outer shell hole.
(B6) In any above embodiment described in (B1)-(B5), the inserting the insert includes a first insert and a second insert, the first insert spaced from the second insert according to a standard rail spacing distance of a railway.
Changes may be made in the above methods and systems without departing from the scope hereof. It should thus be noted that the matter contained in the above description or shown in the accompanying drawings should be interpreted as illustrative and not in a limiting sense. The following claims are intended to cover all generic and specific features described herein, as well as all statements of the scope of the present method and system, which, as a matter of language, might be said to fall therebetween.
This application benefits from and claims priority to U.S. Provisional patent application Ser. No. 63/264,827, filed Dec. 2, 2021, the entire disclosure of which is incorporated by reference herein in its entirety as if fully set forth.
Number | Date | Country | |
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63264827 | Dec 2021 | US |