This invention relates to improvements in rail seat assemblies with concrete ties and cast in support shoulders.
Heavy haul railroad track in the USA has been experienced wide gauge and rail seat abrasion due to insufficient lateral and longitudinal support from the side and the bottom of the rail. Frequent maintenance is required to keep the track in good condition.
U.S. Pat. No. 4,757,945 discloses a sleeper with a recessed rail seat and further recesses in the rail seat to accommodate the feet of a rail insulator interposed between the shoulder and the rail base.
USA patent application 2011/0047786 discloses a guide plate used in conjunction with an abrasion plate on the rail seat.
It is an object of this invention to provide a rail seat that requires less maintenance.
To this end the present invention provides a rail seat which includes
This invention is predicated on the insight that the e clip fastening rail seats have an inadequate area bearing against the longitudinal edges of the rail base. At present the contact is the width of the rail clip support shoulder. The improvement is achieved by providing a recess in the concrete tie and an abrasion plate that covers the floor of the recess and its sides parallel to the rail base. The abrasion plate includes ribs which seat in additional recesses in the tie to retard longitudinal movement. The anti-abrasion assembly preferably has four flanges which wrap around the top of concrete tie to prevent dust particles from entering and abrading the concrete rail seat. These flanges also wrap around the support shoulder for additional resistance to longitudinal movement. The new fastening components are designed to provide 8.5″ of lateral support along the side of the rail base while the traditional e clip fastener provides only 3″ of lateral support.
The clip provides the clamping force to the rail base through the heavy duty insulator.
The interlock feature between the anti-abrasion assembly and the concrete tie also minimizes relative movement between abrasion plate and concrete tie, which results in less concrete surface abrasion. The new fastening system is expected to provide longer component service life and less track maintenance.
In another aspect this invention provides a shoulder with a deep front rib which sits flush with the concrete rail seat to allow the anti-abrasion assembly and concrete tie to provide lateral full bearing to the rail. This preferred shoulder has a distance from the top of the clip tunnel to the top of the front rib which is 5 times the distance from the top of the clip tunnel to the clip heel surface.
Preferably the shoulder has a rectangular recess which interlocks with the anti-abrasion plate assembly and hold it in place before and during track installation.
A preferred embodiment of the invention will be descried with reference to the drawings in which
The rail base is clamped on top by the heavy duty insulator liner 4 and steel insert 5, the clamping force is provided by clip 2. The clip is supported by shoulder 1 which is cast in the concrete tie 8.
From the above it can be seen that the present invention provides an arrangement that reduces the need for maintenance. Testing of these ties to AREMA wear and abrasion standards show that they perform well under load. The full bearing aspects of the seat allows for reduced pressure on the components and they last much longer than conventional elastic fasteners. The rail roads can continue to use their conventional equipment to install, remove and maintain these ties without having to order specialty tools or change their standard operation procedures.
Those skilled in the art will also appreciate that this invention may be implemented in embodiments other than those described without departing from the core teaching of the invention.
Number | Date | Country | Kind |
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2015901265 | Apr 2015 | AU | national |
Filing Document | Filing Date | Country | Kind |
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PCT/US2016/026188 | 4/6/2016 | WO | 00 |