FIELD OF INVENTION
The present invention relates generally to tie-supported railroad tracks and more particularly to anti-mud pumping railroad ties, pre-plated railroad ties and related methods.
BACKGROUND
In the operation of railroads, in wet climatic conditions, such as those encountered in the southeastern region of the United States, a phenomenon known as mud-pumping occurs. Because train loads are imposed on railroad ties periodically or sequentially by the spaced wheels of the locomotive and railroad cars of each train, as the train moves along the track there is periodic up and down movement of the railroad ties which support two rails upon ballast. This up and down motion of the ties on and in the ballast, is sometimes called pumping.
When the ballast is dry, ballast abrasion of the railroad ties forming the track caused by pumping is inconsequential. However, when the ballast is wet, the pumping action tends to segregate the particles in the ballast or aggregate, bringing the fine particles to the top of the ballast.
In this state, with the water in the ballast acting as a lubricant, the fine particles in the ballast act like sandpaper, as the ties move up and down in the manner mentioned above. This is called mud-pumping. As a result, the ties are damaged, greatly shortening the useful life of the ties so eroded and requiring premature tie replacement. Often the useful life of such tie is shortened by more than fifty percent.
In the past, the solution to mud-pumping has been to simply replace the damaged ties at frequent intervals, making operation of the railroad more costly.
BRIEF SUMMARY AND OBJECTS OF THE INVENTION
In brief summary, the present invention overcomes or substantially alleviates problems of the past related to railroad tie erosion due to mud-pumping. More specifically, the present invention is directed to novel anti-mud pumping railroad ties, anti-mud pumping pre-plated railroad ties and related methods.
With the foregoing in mind, it is a primary object of the present invention to overcome or substantially alleviate problems of the past related to railroad tie erosion due to mud-pumping.
Another paramount object is the provision of anti-mud pumping railroad ties, anti-mud pumping pre-plated railroad ties and related methods.
These and other objects and features of the present invention will be apparent from the detailed description taken with reference to accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective, broken way to illustrate an anti-mud pumping coated railroad tie in accordance with the principles of the present invention, where the tie per se is formed of concrete;
FIG. 1 is a perspective broken way to illustrate an anti-mud pumping coated railroad tie in accordance with the principles of the present invention, where the tie is a wooden tie;
FIG. 3 illustrates a further anti-mud pumping coated railroad tie in accordance with the principles of the present invention, the tie being formed of concrete and the protective covering encapsulating all surfaces except the top surface of the tie;
FIG. 4 illustrates an anti-mud pumping coated tie in accordance with the principles of the present invention, where the tie is made of wood and an abrasion-resistant covering is disposed across the top and part way up each vertical surface of the tie;
FIG. 5 illustrates, in cross section, a further anti-mud pumping coated railroad tie in accordance with the principles of the present invention, where the tie is formed of concrete and the abrasion-resistant covering on all exposed surfaces except the top surface comprises a wear-resistant composite material;
FIG. 6 is a fragmentary cross section illustrating an anti-mud pumping coated railroad tie in accordance with the present invention, where the coating comprises protective layers which are bonded to exposed surfaces of the wooden tie;
FIG. 7 is a cross section similar to FIG. 3, further including re-enforcement bridging between the protective covering and the concrete tie per se;
FIG. 8 is a fragmentary cross section of a further anti-mud pumping protected railroad tie in accordance with the principles of the present invention illustrating a different form of re-enforcement bridging between the concrete tie and the protective covering;
FIG. 9 is a perspective view, shown partially in cross section, illustrating a protective coating at the bottom of a wooden tie;
FIG. 10 is a perspective illustration of one method by which a railroad tie may be coated with an anti-mud pumping layer;
FIG. 11 is a perspective representation of another manner by which a railroad tie per se may receive an anti-mud pumping covering through emersion in a bath of liquid synthetic resinous material;
FIG. 12 is a diagrammatic representation of a displacement process by which a railroad tie may receive an anti-mud pumping covering;
FIG. 13 is a flow chart illustrating one way in which railroad ties may receive an anti-mud pumping coating;
FIG. 14 is an enlarged fragmentary cross section illustrating a pre-plated railroad tie having an anti-mud pumping coating at the bottom thereof;
FIG. 15 is a fragmentary cross section showing a pre-plated tie protected by an anti-mud pumping layer at the bottom and partially up each vertical surface of the railroad tie; and
FIG. 16 is a fragmentary cross section illustrating a pre-plated railroad tie having an anti-mud pumping layer on all exposed surfaces.
DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS
Reference is now made to the drawings wherein like numerals are used to designate like parts throughout. The present invention relates to the field of anti-mud pumping of railroad ties and applies to railroad ties comprised of any suitable material including concrete ties 20, wooden railroad ties 22, railroad ties 24 formed of synthetic resinous material and any other type.
With specific reference to FIGS. 1-9, the anti-mud pumping protective covering 40 may entirely encapsulate the ties 20, 22, 24 with a layer of abrasion-resistant material. See FIGS. 1 and 2. In the alternative, the anti-abrasion covering or layer may contiguously engage the bottom surface 28 of the tie, as well as the vertical edges 30, 32 and 34. See FIGS. 3, 7 and 8.
In other forms, the anti-mud pumping, abrasion-resistant covering or layer 40 may contiguously cover the entire bottom surface 28 and only part of the vertical surfaces 30, 32 and 34 of the tie. See FIG. 4.
The present anti-mud pumping invention may also comprise an abrasion-resistant layer 40 which primarily covers only the bottom surface 28 of the associated railroad tie, as shown in FIG. 9. FIG. 9 does illustrate that the bottom corners of the tie are also protected by the layer at sites 36.
The covering 40 may comprise non-reinforced wear-resistant synthetic resinous material, reinforced wear-resistant synthetic resinous material, composite material, graphite or any other suitable material which will significantly increase the useful life of a railroad tie subjected to the mud-pumping phenomenon mentioned above. FIGS. 1-4 depict the abrasion-resistant covering 40 as being comprised of synthetic resinous material as does FIG. 9.
FIG. 5 illustrates a covering 42 of composite or graphite material, formed into a concave rectangular configuration slightly larger than the dimensions of the railroad tie 20, wherein the composite or graphite covering 42 is secured to bottom and vertical surfaces 28, 30, 32, and 34 by a bonding agent 44.
FIG. 6 illustrates utilization of preformed, predimensioned separate protective layers 42 and 48 secured to plastic railroad tie 24 in the assembled condition using a suitable bonding agent 44.
FIGS. 7 and 8 illustrate utilization of two forms of re-enforcement 50 and 52, respectively, to ensure the covering 40 will not separate from the tie during the mud-pumping phenomenon mentioned above.
Reference is now made to FIGS. 10-13, which depict various ways that a wooden, concrete, plastic, or other railroad tie can be equipped with an anti-mud pumping covering. It is to be understood that the covering may be of any suitable type, including the types described in conjunction with FIGS. 1-9. FIG. 10 illustrates application of an anti-mud pumping layer to a conventional tie 20, 22, 24 utilizing a spraying technique from which liquid effluent covering material is emitted under pressure from nozzle 60 and sets and cures as a solid on the surfaces of the tie. It is to be understood that the anti-mud pumping coating may be of any desired thickness and covers at least the bottom surface 28 of the railroad tie and, if desired, the vertical sides 30, 32, and 34, in whole or in part, or the vertical sides 30, 32, and 34 and the top 33. The liquid 62 emitted from spray nozzle 60 becomes contiguous with and adheres to each tie surface to which it is applied, prior to taking a set and curing. For some applications, a single coat of spray 62 may be adequate, while, for others, the spray 62 may have to be applied two or more times to produce the desired thickness of protection for the anti-mud pumping covering.
FIG. 11 illustrates an emersion tank approach to equipping a railroad tie 20, 22, 24 by which anti-mud pumping coverings mentioned in conjunction with FIGS. 1-9 may be obtained. Essentially, a container 64 is provided in which a suitable liquid coating material 66, with or without a reinforcement material, is disposed. Liquid may solidify at room temperature or at a higher temperature. The railroad tie is lowered a sufficient distance into the liquid 66 to cover the desired amount of the tie. The amount of dwell-time in the liquid 66 is to be determined by those skilled in the art. Further, the tie may be lowered into the liquid 66 for a given dwell-time repeatedly until the appropriate coating thickness for the anti-mud pumping layer is achieved.
An alternative way of totally or partially providing a railroad tie 20, 22, 24 with an anti-mud pumping coating across a desired exposed area of the tie, is illustrated in FIG. 12. The tie is suspended from a cable 68 forming a part of a crane or the like, and is displaced both horizontally and vertically by the crane so that the tie is wholly or partially immersed in the bath 66 of liquid material from which the anti-mud pumping coating is obtained. In FIG. 12, the liquid coating material 66 is contained within an elongated container 70, providing the appropriate amount of dwell-time.
Reference is now made to FIG. 13 which illustrates, in flow chart form, a procedure available in accordance with the present invention which may be used in whole or in part at an installation site where anti-mud pumping ties are being used to replace ties damaged by mud-pumping or at a manufacturing site remote from a railroad track comprising ties damaged by mud-pumping.
The protocol of FIG. 13, identified generally by the numeral 72, accommodates washing or cleaning of ties, which are used and/or soiled, at station 74. Ties so washed or cleaned are allowed to dry, depicted as drying station 76. This drying station may be either drying at ambient temperature or at an elevated temperature, as determined by those skilled in the art. Establishment of an anti-mud pumping coating as explained in conjunction with FIGS. 1-9 above utilizing any of the methods of FIGS. 10-12, or any other method, is illustrated as taking place at coating station 78. Typically when coatings in accordance with the present invention, particularly reinforced or non-reinforced synthetic resinous coatings are involved, a certain interval of time is required for setting and curing to take place, illustrated in FIG. 13 at station 80. Curing may take place at station 80 in any effective manner, such as at ambient temperature, at an elevated temperature and/or utilization of curing compounds. Once the suitably coated railroad ties have been cured, and are ready for use, they may be placed in inventory at 80, shipped to a remote installation site where railroad repairs are being made to cure mud-pumping problems as shown at 82 or, where the protocol of FIG. 13 is being practiced, used immediately at that location as depicted at 84 in FIG. 13.
The present invention, in some embodiments, accommodate pre-plating of railroad ties, the ties comprised of any suitable material, so that available pre-plated ties further comprising an anti-pumping coating in accordance with the present invention are fabricated for immediate use by simply removing a tie damaged by mud-pumping, together with its two affixed railroad plates from spaced railroad rails and replacing the removed tie with a pre-plated tie in accordance with the present invention. More specifically, in reference to FIG. 14, tie 22 of FIG. 9 is illustrated as being pre-plated by the installation of two tie plates generally designated 90, using any suitable fastener, railroad spike 92 being illustrated for exemplary purposes in FIG. 14. While only one plate 90 is illustrated in FIG. 14, it is to be understood that such a plate is interposed beneath each of two railroad rails 94 shown in phantom lines in FIG. 14 resting upon tie plate surface 96. Each railroad rail 94 is held in the indicated position by mechanisms which are conventional and not illustrated in FIG. 14.
Similarly, the other anti-mud pumping embodiments of the present invention may be pre-plated as well. FIG. 15 illustrates the tie 22 of FIG. 4 in pre-plated form, while FIG. 16 illustrates tie 22 of FIG. 2 in pre-plated form.
The invention may be embodied in other specific forms without departing from the spirit of the central characteristics thereof. The present embodiments therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.
Patent Application
20070012794
