The disclosure relates to an applicator for delivery of a friction control composition to a railhead and a method of using the same to control friction between the railhead and train wheels.
The emission of high noise levels and extensive wear of steel wheels and steel rails is a common problem in rail systems, including freight, passenger and mass transit trains. Such problems are directly attributed to the frictional forces generated between the wheel and the railhead during operation of the system. In addition to noise problems and extensive wear of the wheels and rails, negative friction between the two sliding steel surfaces cause slip-stick oscillations. This, in turn, results in inefficient as well as sub-optimum performance.
In order to control friction, it has long been the practice to apply grease or friction control compositions onto the rail, including onto the railhead as well as the sides of the rail. Most notably, such compositions have been applied at curves, inclines, turnouts, switches, etc. Friction control compositions can either reduce or increase the friction when necessary to improve train performance and reduce wear on both the railhead and the train wheels.
In order to increase friction between the train wheel and the rail, the friction control composition is typically placed on the railhead. Applicators used to place friction control compositions onto railheads are called top of rail (TOR) applicators. In normal practice, TOR applicators are periodically spaced along the length of the rail track. The spacing of TOR applicators is typically dependent on the ability of the friction control composition to carried down the rail. Unfortunately, when compared to applicators placed on the side of the rail, TOR applicators, in direct contact with the train wheel, are more likely to be damaged or destroyed by train wheels.
TOR applicators have been developed over the years to address this issue. However, such applicators have proved to be inadequate for a number of reasons. For example, in some prior art applicators, the friction control composition typically does not reach the center of the railhead. As a result, the friction control composition is not effectively carried down the rail. In other cases, substantial amounts of the friction control composition are wasted because the friction control composition ends up leaking down the sides of the rail and off the railhead. In other instances, while prior art TOR applicators place the friction control composition on the railhead, the applicator itself is damaged or destroyed by impact when hit by train wheels. Thus, such TOR applicators of the prior art become inoperable from impact damage.
TOR applicators that effectively place the friction control composition onto the railhead such that the friction control composition is efficiently carried down the track are desired. In addition, such TOR applicators need to be relatively safe from being damaged or destroyed from the impact of train wheels.
It should be understood that the above-described discussion is provided for illustrative purposes only and is not intended to limit the scope or subject matter of the appended claims or those of any related patent application or patent. Thus, none of the appended claims or claims of any related application or patent should be limited by the above discussion or construed to address, include or exclude each or any of the above-cited features or disadvantages merely because of the mention thereof herein.
In an embodiment of the disclosure, an applicator is provided for delivering a friction control composition to a railhead. The applicator is composed of a housing, a bar positioned in the housing and an exit orifice on the upper portion of the bar for delivering the friction control composition to the crown of the railhead.
In another embodiment of the disclosure, an applicator is provided for delivering a friction control composition to a railhead. The applicator is composed of a housing, an elastomeric bar positioned in the housing, an entry port for pumping the friction control composition into a passageway, and an exit port for pumping the friction control composition onto the railhead.
In another embodiment of the disclosure, an applicator is provided for delivering a friction control composition to a railhead. The applicator is composed of a housing, a bar positioned in the housing, an entry port located on the lower portion of the slope for feeding the friction control composition into a passageway and an exit orifice on the upper portion of the bar for delivering the friction control composition to the crown of the railhead from the passageway. The upper portion of the bar slopes away from the friction control composition exit orifice. In an embodiment, the upper portion of the bar slopes away from the friction control composition exit at an angle between from about 5 to about 15 degrees. The applicator assembly may also contain a platform for the bottom surface of the housing, a clamp for coupling the applicator onto the railhead via the platform and a leveler.
In another embodiment of the disclosure, an applicator assembly is provided for delivering a friction control composition to a railhead. The applicator assembly comprises an applicator composed of a housing, a bar positioned in the housing and an exit orifice on the upper portion of the bar for delivering the friction control composition to the crown of the railhead. The applicator assembly may also contain a platform for the bottom surface of the housing, a clamp for coupling the applicator onto the railhead via the platform and a leveler.
In another embodiment of the disclosure, an applicator assembly is provided for delivering a friction control composition to a railhead; the applicator assembly comprising a housing, an elastomeric bar positioned in the housing, an entry port for pumping the friction control composition into a passageway and an exit port for pumping the friction control composition onto the railhead. The applicator assembly further contains a platform onto which the bottom surface of the housing is seated, a leveler attached to the platform and a clamp coupled to the platform for affixing the applicator assembly onto the railhead.
In another embodiment of the disclosure, an applicator assembly is provided for delivering a friction control composition to a railhead. The applicator assembly comprises an applicator composed of a housing, a bar positioned in the housing, an entry port located on the lower portion of the slope for feeding the friction control composition into a passageway and an exit orifice on the upper portion of the bar for delivering the friction control composition to the crown of the railhead from the passageway. The applicator assembly may also contain a platform for the bottom surface of the housing, a clamp for coupling the applicator onto the railhead via the platform and a leveler.
In another embodiment, a method of delivering a friction control composition onto the crown of a railhead using an applicator assembly is provided. The applicator assembly is composed of an applicator and a clamp. The applicator is composed of a housing, a bar positioned in the housing and a friction control composition exit orifice on the upper portion of the bar. The upper portion of the bar slopes away from the friction control composition exit orifice. In an embodiment, the upper portion of the bar slopes away from the friction control composition exit at an angle between from about 5 to about 15 degrees. The clamp couples the platform onto a railhead of a rail. In the method, the friction control composition is pumped through the exit orifice onto the crown of the railhead.
In another embodiment of the disclosure, a method of delivering a friction control composition onto the crown of a railhead using an applicator assembly is provided. The applicator assembly is composed of an applicator and a clamp. The applicator is composed of a housing, a bar positioned in the housing and a friction control composition exit orifice on the upper portion of the bar. The bar of the applicator has an entry port for the friction control composition. In addition, the applicator has a passageway from the friction control composition entry port to the friction control composition exit orifice for transporting the friction control composition. The upper portion of the bar slopes away from the friction control composition exit orifice. In an embodiment, the upper portion of the bar slopes away from the friction control composition exit at an angle between from about 5 to about 15 degrees. The clamp couples the platform onto a railhead of a rail. In the method, the friction control composition is pumped through the exit orifice onto the crown of the railhead. In the method, the friction control composition is pumped through the exit orifice onto the crown of the railhead.
Accordingly, the present disclosure includes features and advantages which are believed to enable it to most effectively place friction control compositions onto rails.
The following figures are part of the present specification, included to demonstrate certain aspects of various embodiments of this disclosure and referenced in the detailed description herein:
Characteristics and advantages of the present disclosure and additional features and benefits will be readily apparent to those skilled in the art upon consideration of the following detailed description of exemplary embodiments of the present disclosure and referring to the accompanying figures. It should be understood that the description herein and appended drawings, being of example embodiments, are not intended to limit the claims of this patent or any patent or patent application claiming priority hereto. On the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the claims. Changes may be made to the particular embodiments and details disclosed herein without departing from such spirit and scope.
In showing and describing preferred embodiments in the appended figures, common or similar elements are referenced with like or identical reference numerals or are apparent from the figures and/or the description herein. The figures are not necessarily to scale and certain features and certain views of the figures may be shown exaggerated in scale or in schematic in the interest of clarity and conciseness.
As used herein and throughout various portions (and headings) of this patent application, the terms “disclosure”, “present disclosure” and variations thereof are not intended to mean every possible embodiment encompassed by this disclosure or any particular claim(s). Thus, the subject matter of each such reference should not be considered as necessary for, or part of, every embodiment hereof or of any particular claim(s) merely because of such reference.
The term “coupled” and the like, and variations thereof, as used herein and in the appended claims are intended to mean either an indirect or direct connection or engagement. Thus, if a first device couples to a second device, that connection may be through a direct connection, or through an indirect connection via other devices and connections.
Certain terms are used herein and in the appended claims to refer to particular components. As one skilled in the art will appreciate, different persons may refer to a component by different names. This document does not intend to distinguish between components that differ in name but not function.
Also, the terms “including” and “comprising” are used herein and in the appended claims in an open-ended fashion, and thus should be interpreted to mean “including, but not limited to . . . .” Further, reference herein and in the appended claims to components and aspects in a singular tense does not necessarily limit the present disclosure or appended claims to only one such component or aspect, but should be interpreted generally to mean one or more, as may be suitable and desirable in each particular instance.
Preferred embodiments of the present disclosure thus offer advantages over the prior art and are well adapted to carry out one or more of the objects of this disclosure. However, the present disclosure does not require each of the components and acts described above and are in no way limited to the above-described embodiments or methods of operation. Any one or more of the above components, features and processes may be employed in any suitable configuration without inclusion of other such components, features and processes. Moreover, the present disclosure includes additional features, capabilities, functions, methods, uses and applications that have not been specifically addressed herein but are, or will become, apparent from the description herein, the appended drawings and claims.
The top of rail applicator (TOR) disclosed herein may be used to deliver a friction control composition (or a lubricant) to a railhead, most notably the crown of the railhead. The TOR applicator, when affixed to a railhead, is less likely to be damaged by a train wheel. As such, the friction control composition is more efficiently carried down the top of the railhead.
As illustrated, TOR applicator assembly 100 includes a TOR applicator. The TOR applicator contains bar 102. Bar 102 may be seated in bar housing 104. Bar housing 104 may be characterized as having a front wall 104A (which faces, when attached to the rail, the field side of the rail), a side wall 104B, a back wall 104C and a bottom wall 104D. As illustrated in
Since bar 102 sits inside of housing 104 and may be releasably attached, it can easily be replaced. Thus, when bar 102 is damaged, destroyed or otherwise rendered less efficient due to wear and tear, it may be removed and replaced with a fresh bar. Bar 102 may be releasably attached to bar housing 104 with mechanical fasteners or self-tapping screws.
As shown in
In an alternative embodiment, the bar may be integrally formed with the housing.
In some instances, front wall 104A and side wall 104B of bar housing 104 (as illustrated in
In a preferred embodiment, shown in
In a preferred embodiment, front wall 104A and side wall 104B may be sloped such that the top surface of the front wall and side wall is sloped away from exit orifice 114, typically between 0.5 inches and 1.25 inches below the exit orifice.
Thus, in an embodiment, such as shown in
As illustrated in
As shown in
A conventional pump, valves and hoses are used for supplying the friction control composition to port 112, through passageway 110 and onto railhead through exit orifice 114.
In
In an alternative embodiment, the TOR applicator may not have a housing such that entry port 111 feeds into a unitary element having an exit orifice.
Bar 102 may further include sealant 116, as illustrated in
In an embodiment, sealing member 116 may be a gasket. Suitable gaskets include Teflon ropes, such as those available commercially from McMaster Carr as product Part #8824K11 Flange Mount PTFE Rope Seal. In addition, sealing member 116 may be composed of an elastomer or a rubber.
At times it may be desirable to move the TOR applicator away from railhead 108 during maintenance such as during rail grinding where the railhead 108 is reverted back to its original profile. Rail grinding requires that objects in the path of the grinder (including the TOR applicator) be moved.
Movement of the TOR applicator away from railhead 108 and towards the field may be accomplished by the use of pivot points 118. As illustrated in
The surface of platform 120 may further have slots 134 for receiving leveling bolts 136. Leveling bolts 136 in
To assure that bar 102 is correctly positioned vis-à-vis railhead 108, leveling bolts 120 on rail foot 20 may be turned and move TOR applicator and thus bar 102 up and down.
TOR applicator may further have one or more shock absorbers 130 to assist in minimizing damage to bar 102. As illustrated in
In at least one embodiment, bar 102 is elastomeric. In a preferred embodiment, the elastomeric bar exhibits a hardness of between 50 Shore A and 75 Shore A. Elastomeric bar 102 is preferably composed of polyurethane, such as a polyurethane commercially available from H&H Urethane and can molded or shaped by methods well known in the art (e.g. injection molding, machining etc).
In certain embodiments of the disclosure, the parts of applicator 50 that are not intended to flex (i.e. bar 102 and shock absorbers 130 are intended to flex) are made of rigid, strong materials that are intended to last much longer than bar 102. Some examples include certain metals such as 1060 Carbon Steel, and 4130 Molybdenum Steels. These parts can be formed by well-known processes found in the prior art such as machining, stamping and molding.
In at least one embodiment of the disclosure, the friction control composition changes the friction, or coefficient of friction, between the steel surfaces from negative to positive and thereby reduces or eliminates the lateral, longitudinal and/or spin creeps with a corresponding reduction or elimination of lateral forces and wheel-rail wear while increasing stability of the train.
The friction control composition may be placed on crown 106 of railhead 108 through orifice exit 114.
The friction control composition is sufficiently viscous to be pumped to be pushed up to the top of the rail from exit orifice on the applicator bar. In some instance, the friction control composition may have a viscosity of at least 2,000 cP @ 25° C., measured on a Model 35 Fann viscometer having a R1B1 rotor and bob assembly rotating at 300 rpm. The problem with a friction modifier with a viscosity of at least 2,000 cP, is that it may require a larger tubular passage through the applicator bar and also a more powerful pump to push the more viscous friction modifier.
Because exit orifice 110 is intended in some embodiments to be at least ⅛th of an inch below railhead 108, it is important that the friction modifier be thixotropic so that it can be “pushed” up hill onto the top of railhead 10. This assures that a significant amount of the friction modifier ends up on the top surface of the rail and is subsequently carried down the track.
In one embodiment of the disclosure, the friction modifier comprises a thixotropic material that flows easily through an orifice in the applicator bar because of shear thinning. However, as a thixotropic material it then becomes more viscous when it is static on the top or the side of the rail. While the thixotropic friction modifier is being pumped through the pump, hoses and applicator bar, shear thinning lowers the viscosity and allows the friction modifier to flow more easily through the tubular passage and out of the applicator.
In at least one other embodiment, the top of rail applicator of the present disclosure is intended to be used only with friction modifying compositions that are thixotropic and thus able to be pushed upward onto the railhead even though the exit orifice is below the level of the railhead by an amount of at least ⅛th of an inch. The thixotropic nature of the friction modifier assures that when the composition leaves the exit orifice at the top surface of the applicator bar from a position below the top of the rail surface it will “climb” up (i.e. be pushed up) the railhead such that a significant amount of the friction modifier ends up on the top surface of the rail and is subsequently carried down the track.
This lower viscosity during pumping allows for a smaller pump and/or a smaller tubular passage. When the thixotropic friction modifier exits the applicator bar it immediately begins to thicken (i.e. become more viscous). This increased viscosity allows for three desirable effects. First the viscous “glob” of friction modifier is thick enough to be pushed up the side of the railhead and toward the center of the top of the railhead because of the backpressure from the pump. Second, the friction modifier in this more viscous state is less likely to run off the side of the rail onto the ground. Third, as the friction modifier material is “sheared” by the train wheel it becomes less viscous again and is more easily carried down the track to allow more distant spacing of applicators. Such materials enable a more consistent distribution of friction modifier down the rail of the track.
In at least one embodiment, the friction modifier composition has the following composition in weight percent (w/w %):
Optionally, the composition may also contain one or more of:
The water insoluble hydrocarbon may be an isoparaffins, vegetable oil, bio-based triglyceride, a fatty oil or a mixture thereof.
In another embodiment, the friction control composition of the friction control composition comprises:
(a) from 15 to 29 w/w % water
(b) from 4 to 13 w/w % rheology additive
(c) from 11 to 28 w/w % water insoluble hydrocarbon (e.g. isoparaffins, vegetable oils, bio-based triglycerides or fatty oils).
(d) from 22 to 40 w/w % freezing point depressant
(e) from 9 to 24 w/w % liquid or solid friction modifier
(f) from 1 to 6 w/w % liquid or solid lubricant.
As noted above, the composition may also optionally contain one or more of:
(g) from 1 to 3 w/w % surfactant or wetting agent
(h) from 0.1 to 0.5 w/w % corrosion inhibitor, and/or
(i) from 0.05 to 0.2 w/w % biocide/fungicide agent
It has been found that adding a water insoluble hydrocarbon to the composition (e.g. an isoparaffin such as SOTROL 220) helps depress the freezing point and also helps stabilize or even improve the rheology of the formulation. This is especially true when the water insoluble hydrocarbon is compared with other freezing point depressants such as glycerin. Other water insoluble hydrocarbons that have environmental advantages over isoparaffins are vegetable oils, bio-based triglycerides and fatty oils such as canola oil. The oils do not have the same freezing point advantages as isoparaffins but they are environmentally friendly.
The addition of the water insoluble hydrocarbon (either isoparaffins or oils) in the partially water based friction control composition is counterintuitive because one would have guessed that it would not mix well with the water and would in all likelihood separate. However, we believe that the clay has receptor sites that allow the water insoluble hydrocarbon to bind onto the clay and keep the final product homogenous. The result is a composition that may contain lower amounts of water and in the case of isoparaffins lower amounts of soluble polyalcohol freezing point depressants such as glycerine. As pointed out above, water based friction control compositions have problem with maintenance and typical freezing point depressants can cause negative rheology effects on the composition.
An example of a thixotropic friction modifier material usable in the current is “TOR Armor” from Whitmores of Rock Wall, Tex. Thixotropic materials allow for pumps, hoses and applicators with optimum sizes. In at least one embodiment, the replaceable applicator bar is made of a polyurethane insert. This assures that the bar flexes if it is hit by a train wheel to help prevent damage. However, the bar is also tough enough to keep its rough profile even after such an impact.
This application claims the benefit of U.S. patent application Ser. No. 62/124,240 filed on Dec. 12, 2014 and further is a continuation-in-part application of U.S. patent application Ser. No. 14/655,903, filed on Jun. 26, 2015, a national stage entry of PCT/US14/10188 which in turn claims the benefit of U.S. Patent Application Ser. No. 61/963,448, filed on Dec. 4, 2013; U.S. Patent Application Ser. No. 61/962,265 filed on Nov. 4, 2013; U.S. Patent Application Ser. No. 61/958,789, filed on Aug. 6, 2013; U.S. Patent Application Ser. No. 61/850,923 filed on Feb. 26, 2013; U.S. Patent Application Ser. No. 61/850,690, filed on Feb. 21, 2013; and U.S. Patent Application Ser. No. 61/848,596, filed on Jan. 7, 2013, all of which are herein incorporated by reference.
Number | Date | Country | |
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62124240 | Dec 2014 | US | |
61963448 | Dec 2013 | US | |
61962265 | Nov 2013 | US | |
61958789 | Aug 2013 | US | |
61850923 | Feb 2013 | US | |
61850690 | Feb 2013 | US | |
61848596 | Jan 2013 | US |
Number | Date | Country | |
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Parent | 14655903 | Jun 2015 | US |
Child | 14967264 | US |