The present invention is a method of joining and repairing rails.
In the prior art, rails are produced in standard lengths by steel producers. The rails ultimately are required to be joined together in the field. Conventional methods of welding rails together include, for example, thermite welding, and flash-butt welding. The conventional methods result in a heat-affected zone in the joined rails. The heat-affected zone typically extends outwardly into both rails, from a weld interface or joint at which the two rails are joined by molten metal.
The material in the heat-affected zone has been adversely affected by heat from the molten metal used in the conventional welding processes. Typically, the material in the heat-affected zone is weaker, or softer, than material outside the heat-affected zone. As is well known in the art, because the heat-affected zones provide regions in which the characteristics of the material (e.g., steel) vary widely, the rails are prone to failure in or near the heat-affected zones, sometimes at the weld interface.
As can be seen in
For the foregoing reasons, there is a need for a method and a system for joining rails together that overcomes or mitigates the defects and deficiencies of the prior art.
In its broad aspect, the invention provides a method of forming a fused rail assembly in which one or more heating elements are positioned in a gap between first and second end faces of aligned first and second rails. The end faces are covered by a non-oxidizing atmosphere, and the heating elements are energized, to heat portions of the first and second rails to a predetermined hot working temperature. While one or more of the first end faces is moving transversely relative to center lines of the rails, and while the heated portions are at the predetermined hot working temperature, the first and second end faces are engaged with each other, to fuse together, forming the fused rail assembly. The transverse motion may begin before or after the first and second ends are engaged.
The invention will be better understood with reference to the attached drawings, in which:
In the attached drawings, like reference numerals designate corresponding elements throughout. Reference is first made to
In one embodiment, the method of forming the fused rail assembly 120 preferably includes providing a first rail 122 having a first rail head 123. The first rail 122 ends at a first end face 126 thereof. A second rail 128 is provided that has a second rail head 130. As can be seen in
Preferably, the first and second rails 122, 128 are positioned to locate the first and second end faces 126, 134 facing each other, and to align the first and second rail center lines 124, 132 (
It is also preferred that one or more heating elements 140 are provided. As can be seen in
A non-oxidizing or inert atmosphere is provided, to cover the first and second end faces 126, 134 while they are heated. In
Once the non-oxidizing atmosphere is in place, the heating element 140 is energized, to heat the first end face 126 and a first length portion 146 of the first rail 122 extending from the first end face 126 into the first rail 122 by induction heating to a predetermined hot working temperature, at which the first end face 126 and the first length portion 146 are plastically deformable (
Those skilled in the art would appreciate that a hot working temperature of a metal is less than a melting temperature thereof. A metal (i.e., metal or alloy) may have a range of hot working temperatures. It will be understood that the predetermined hot working temperature is an optimum hot working temperature. For instance, a relatively low hot working temperature may be considered optimum due to relatively low energy inputs.
Those skilled in the art would appreciate that the heating elements may include one or more induction coils.
Preferably, where more than one heating element 140 is utilized, all the heating elements 140 may be energized at substantially the same time, and de-energized at substantially the same time. However, as will be described, it may be advantageous to energize certain heating elements before others, to preheat the heads 123, 130.
Those skilled in the art would appreciate that, when all of the heating elements 140 are energized, all of the first and second end faces 126, 134 and the first and second length portions 146, 148 are heated, by induction heating. The first length portion 146 is a portion of the first rail 122, adjacent to the first end face 126, that is heated to the predetermined hot working temperature. The second length portion 148 is a portion of the second rail 128, adjacent to the second end face 134, that is heated to the predetermined hot working temperature.
It will be understood that the first and second length portions 146, 148 are schematically represented in
It is preferred that one or more of the first and second rails 122, 128 is subjected to transverse motion thereof in at least one direction that is at least partially transverse to the first and second rail center lines 124, 132. In
It will also be understood that the transverse directions generally indicated by arrows “A1”, “A2”, “B1”, and “B2” are exemplary only. It will be understood that the transverse motion may be in any direction relative to the center lines 124, 132, and may be at least partially nonlinear. It will be understood that the transverse motion may be repetitive, and the transverse motion may be at any suitable frequency and directions.
As soon as the first end face 126 and the first length portion 146 and the second end face 134 and the second length portion 148 are at the predetermined hot working temperature, the heating elements 140 preferably are removed from the opening 138. It will be understood that the cover 144 may also be removed once the heating elements 140 are de-energized, and the non-oxidizing atmosphere may be allowed to diffuse into the ambient atmosphere. The heating elements 140 may be de-energized after their removal.
While one or more of the first and second rails 122, 128 are subjected to the transverse motion, and while the first end face 126 and the first length portion 146 and the second end face 134 and the second length portion 148 are at the predetermined hot working temperature, the first and second end faces 126, 134 preferably are engaged with each other, to at least partially plastically deform the first and second end faces 126, 134 and the first and second length portions 146, 148. As a result, the first and second end faces 126, 134 and the first and second length portions 146, 148 are at least partially fused together to form the fused rail assembly 120, as will be described. The first end face 126, the first length portion 146, the second rail face 134, and the second length portion 148 are sometimes collectively or individually herein referred to as heated portions.
As can be seen in
It will be understood that, if preferred, the transverse motion of one or both of the first and second rails 122, 128 may alternatively commence after the first and second ends 126, 134 have been engaged with each other.
The transverse motion of one or both of the rails 122, 128 while the first and second end faces 126, 134 are engaged with each other and at the predetermined hot working temperature results in the shearing of at least part of the material that is in the heated portions, at the predetermined hot working temperature. In practice, after the removal of the heating element 140, the temperature of such material rapidly falls. Accordingly, the first and second end faces 126, 134 are promptly engaged with each other, and pushed against each other, shortly after the heating elements 140 are de-energized and removed. Further plastic deformation after the temperature of the material in the heated portions has fallen below the hot working temperature is then no longer feasible. At that point, transverse motion of one or more of the rails 122, 128 relative to the center lines 124, 132 thereof ceases.
Preferably, the fused rail assembly is cooled (or allowed to cool), to an ambient temperature.
Once the fused rail assembly 120 has been formed, the material in the heated portions thereof that had been heated to the predetermined hot working temperature and subjected to shearing has a generally uniform fine-grained microstructure. The microstructure is substantially consistent throughout the formerly heated portions of the fused rail assembly 120, i.e., the portions thereof that had been heated to the predetermined hot working temperature and subjected to shearing, and there are no heat-affected zones therein, providing a uniformly strong fused rail assembly 120 throughout.
The fused rail assembly 120 does not include a heat-affected zone, with weakened or softened regions, because the material in the heated portion is only heated to the predetermined hot working temperature, that is, such material is not heated to its melting temperature.
It has been determined that most of the energy consumed in the method of the invention, i.e., approximately 98 percent, is the electrical energy provided to the heating elements. The balance of the energy consumed is utilized in generating the transverse motion, and in engaging the first and second rails with each other.
In one embodiment, after the heating elements are de-energized and withdrawn, the heads 123, 130 preferably are only lightly engaged with each other, and upon such engagement, one or both of the rails 122, 128 are subjected to transverse motion thereof, until further transverse motion is not feasible.
It will also be understood that only minimal force is used to engage the first and second ends 126, 134. This has been found, surprisingly, to provide better results than forceful engagement. It is believed that better results are achieved with less engagement or forging force because applying the lower engagement (compression) force permits more thorough shearing of the heated portions to take place, while the first and second end faces 126, 134 are engaged.
The induction coils of the heating elements may be energized at different times, and at different rates.
As will be described, due to the cross-sectional shape of the rails 122, 128, with the rail heads 123, 130 being thicker than the web and the foot, it is preferred that the first and second end faces 126, 134 at the respective heads 123, 130 are pre-heated.
As described above, while the material in the heated portions is at the predetermined hot working temperature, and when the first and second end faces 126, 134 are pushed against each other, such material is plastically deformed. Those skilled in the art would appreciate that, once the fused rail assembly 120 has been formed, some of the material of the previously heated portions may extend outwardly, e.g., beyond the first and second rail heads 123, 130. In effect, some of the material in the heated portions may be squeezed outwardly, when the first and second end faces 126, 134 are engaged with each other. As an example, excess top and side material 150, 152 is illustrated in
It will be understood that the fused rail assembly 120 without any excess material thereon is illustrated in
Although the method of the invention does not produce a joint or weld interface, a dashed line “X” in
In
Preferably, the excess top material 150 and the excess side material 152 is to be removed so that, where the first and second end faces 126, 134 are fused together, the first and second heads 123, 130 are horizontally (or substantially horizontally) aligned (
The design profile “D” also includes a field face “FF” extending downwardly from the field corner “FC”, and a gauge face “GF” extending downwardly from the gauge corner “GC”. The design profile “D” also includes upper fishing surfaces “UF” located adjacent to the field and gauge faces “FF”, “GF”. As can be seen in
Preferably, the excess top material 150 (
It will be understood that, as can be seen in
Similarly, the field head sides 156A, 156B (
As can be seen in
From the foregoing, it can be seen that, in the process of the invention, it is preferred that the heated portions of the rails 122, 128 extend a substantially uniform distance into the first and second rails 122, 128. The first and second heads 123, 130 of the first and second rails 122, 128 (
It will be understood that, as noted above, the heating elements heat the heated portions to the predetermined hot working temperature. In the method of the invention, the heated portions are not heated to a temperature above the hot working temperature, i.e., a melting temperature. Accordingly, in order to provide generally uniformly heated heated portions, it is preferred that the heads are pre-heated, to provide heat to the head portions to a greater extent over time.
In one embodiment, the first length portion 146 preferably includes a first central region 160A that is aligned with a first central head area 162A of the first end face 126 and a first outer region 164A that is adjacent to the first central region 160A (
Those skilled in the art would appreciate that the first and second central regions 160A, 160B may be subjected to heat to a greater extent over time than the first and second outer regions 164A, 164B by utilizing any suitable devices and methods. As noted above, this is preferably achieved by pre-heating the first and second central regions 160A, 160B. For example, the heating elements 140 that are positioned proximal to the first and second central head areas 162A, 162B may be configured to provide heat to the first and second central regions 160A, 160B for a predetermined preheat time period before the heating elements 140 that are positioned for heating the first and second outer regions 164A, 164B are energized. Also, the heating elements 140 that are proximal to the first and second central head areas 162A, 162B may be configured to provide heat at a faster rate than the heating elements 140 that are positioned for heating the first and second outer regions 164A, 164B.
Another embodiment of the method of the invention is illustrated in
Preferably, the intermediate element 266 is positioned in the opening between the first and second end faces 226, 234, to define a first gap 274 between the first end face 226 and the first side 270, and to define a second gap 276 between the second end face 234 and the second side 272 (
The intermediate element defines an intermediate element center line 267 thereof (
It will also be understood that a non-oxidizing atmosphere is provided, covering the first and second end faces 226, 234 and the first and second contact surfaces 278, 280. The region covered by the non-oxidizing atmosphere is identified by reference numeral 242 in
Next, the first heating element(s) 240A preferably are energized, to heat the first end face 226 and a first length portion 246 of the first rail 222 extending from the first end face 226 into the first rail 222 to a predetermined hot working temperature, at which the first end face 226 and the first length portion 246 are plastically deformable. When the first heating element 240A is energized, the first contact surface 278 and a first intermediate element portion 282 of the intermediate element 266 extending from the first contact surface 278 into the intermediate element 266 are heated to the predetermined hot working temperature, at which the first contact surface 278 and the first intermediate element portion 282 are plastically deformable.
The second heating element(s) 240B preferably are also energized, to heat the second end face 234 and a second length portion 248 of the second rail 288 extending from the second end face 234 into the second rail 228 to the predetermined hot working temperature, at which the second end face 234 and the second length portion 248 are plastically deformable. When the second heating element 240B is energized, the second contact surface 280 and a second intermediate element portion 284 of the intermediate element 266 extending from the second contact surface 280 into the intermediate element 266 are heated to the predetermined hot working temperature, at which the second contact surface 280 and the second intermediate element portion 284 are plastically deformable.
The intermediate element 266 may be utilized to join two rails 222, 228 that are made of different material, which may be difficult to join together directly. In these circumstances, for example, the first rail 222 may preferably be heated to a first predetermined hot working temperature, and the second rail 228 may be preferably heated to a different second predetermined hot working temperature. The intermediate element 266 is compatible with the first and second predetermined hot working temperatures. The first heating elements 240A may heat the first end face 226, the first length portion 246, the first contact surface 278, and the first intermediate element portion 282 to the first predetermined hot working temperature. The second heating elements 240B may heat the second end face 234, the second length portion 248, the second contact surface 280, and the second intermediate element portion 284 to the second predetermined hot working temperature.
Various techniques may be utilized to heat the two rails 222, 228 to different temperatures. For example, the gaps 274, 276 may be different widths. Alternatively, or in addition, the heating elements 240A, 240B may be positioned differently relative to the first and second rails 222, 228. The heating elements 240A, 240B may be configured to provide different amounts of heat energy, and they may also provide heat energy over different time periods. For instance, the heating elements 240A, 240B may heat over different preheat periods.
It will be understood that all of the first and second length portions 246, 248 and the first and second intermediate element portions 282, 284 are schematically represented in
In one embodiment, one or both of the first and second rails 222, 228 preferably are subjected to transverse motion in at least one direction that is at least partially transverse to the first and second rail center lines 224, 232. As described above, the transverse motion of the rails 222, 228 may be in any direction that is transverse to the center lines thereof.
While one or both of the first and second rails 222, 228 are subjected to transverse motion, and while the first end face 226, the first length portion 246, the first contact surface 278, the first intermediate element portion 282, the second end face 234, the second length portion 248, the second contact surface 280, and the second intermediate element portion 284 are at the predetermined hot working temperature, the first and second end faces 226, 234 are engaged with the first and second contact surfaces 278, 280 respectively, to at least partially plastically deform the first end face 226, the first length portion 246, the first contact surface 278, and the first intermediate element portion 282, and to at least partially plastically deform the second end face 234, the second length portion 248, the second contact face 280, and the second intermediate element portion 284. Due to such plastic deformation, the first end face 226, the first length portion 246, the first contact surface 278, and the first intermediate element portion 282, are fused together, as will be described. In addition, and also due to such plastic deformation, the second end face 234, the second length portion 248, the second contact surface 280, and the second intermediate element portion 284 are fused together, to form a fused rail assembly 220 (
The first rail 222 preferably is moved in the direction indicated by arrow “2J” in
In one embodiment, the intermediate element 266 may be subjected to transverse motion in one or more intermediate element directions that are at least partially transverse to the intermediate element center line 267. Such transverse motion moves the intermediate element 266 relative to the first and second end faces 226, 234. Like the transverse motion of the rails 222, 228 relative to the center lines thereof, the transverse motion of the intermediate element 266 may be in any directions that are transverse to the intermediate element center line 267.
In one embodiment, the rails 222, 228 and the intermediate element 266 may all be subjected to respective transverse motions thereof while the heated portions are at the predetermined hot working temperature, and while the first and second end faces 226, 234 are engaged with the first and second contact surfaces 278, 280. The transverse motion may commence before or after such engagement.
In another embodiment, only the rails 222, 228 may be subjected to transverse motion thereof while the engagement of the first and second end faces 226, 234 with the first and second contact surfaces 278, 280 takes place. The transverse motion may commence before or after such engagement.
In yet another alternative embodiment, only the intermediate element 266 is subjected to transverse motion relative to the intermediate element center line 267 while the engagement of the first and second end faces 226, 234 with the first and second contact surfaces 278, 280 takes place. The transverse motion may commence before or after such engagement.
In one embodiment, after the fused rail assembly 220 is formed, the fused rail assembly 220 preferably is cooled or allowed to cool to an ambient temperature.
It will be understood that, once the fused rail assembly 220 has been formed, some of the material of the previously heated portions may extend outwardly, e.g., beyond the first and second rail heads 223, 230. As can be seen in
Preferably, the excess top material 250 on respective head top surfaces 254A, 254B of the first and second rail heads 223, 230 of the fused rail assembly 220 is subjected to one or more finishing processes, to remove the excess top material 250 for aligning the respective head top surfaces 254A, 254B with each other. It is also preferred that excess side material 252 on the respective field and gauge head sides 256A, 258A, 256B, 258B of the first and second rail heads 223, 230 of the fused rail assembly 220 is subjected to the finishing processes, to remove the excess side material 252 for aligning the field head sides 256A, 256B of the first and second rail heads 223, 230 with each other, and to align the gauge head sides 258A, 258B of the first and second rail heads 223, 230 with each other.
It will be understood that
It will be understood that the intermediate element 266 may be provided without a plate portion thereof. The plate portion 286 may be included in the intermediate element 266, for instance, to facilitate positioning the intermediate element relative to the first and second rails 222, 228. Also, the plate portion 286 may be used to facilitate transverse movement of the intermediate element 266. For example, one or more devices (not shown) for holding the intermediate element 266 in position, and/or for subjecting the intermediate element 266 to transverse motion, may engage the plate portion 286.
It will also be understood that the intermediate element 266 may include a plate portion that is smaller than the plate portion 286. For example, in
As can be seen in
Preferably, the plate portion 286 of the intermediate element 266 of the fused rail assembly is subjected to one or more finishing processes to provide a modified intermediate element 266′ (
As can be seen in
Those skilled in the art would appreciate that the intermediate element 266 that is shown in
In one embodiment, the first length portion 246 includes a first central region 260A that is aligned with a first central head area 262A of the first rail head 223 and a first outer region 264A that is adjacent to the first central region 260A. Preferably, the second length portion 248 includes a second central region 260A that is aligned with a second central head area 262B of the second rail head 230 and a second outer region 264B that is adjacent to the second central region 260B. It is also preferred that the first central region 260A and the second central region 260B are heated by the first heating element 240A and heated by the second heating element 240B respectively to a greater extent over time than the first and second outer regions 264A, 264B.
As noted above, it is advantageous to provide more heat to the head portions 223, 230 over time, in order to achieve a generally uniform heat distribution in the heated portions. This may be effected by preheating the head portions 223, 230.
Those skilled in the art would appreciate that the first and second central regions 260A, 260B may be subjected to greater heat over time than the first and second outer regions 264A, 264B by utilizing any suitable devices and methods. For example, the heating elements 240A, 240B that are respectively positioned proximal to the first and second central head areas 262A, 262B may be configured to provide more heat over time to the first and second central regions 260A, 260B than the heating elements 240A, 240B that are positioned for heating the first and second outer regions 264A, 264B.
An alternative method of forming the fused rail assembly 320 of the invention is illustrated in
As can be seen in
As noted above, the intermediate element may be used to join (via the intermediate element) rails of dissimilar materials.
The intermediate element 366 defines an intermediate element center line 367 thereof that preferably is aligned with respective center lines 324, 332 of the first and second rails 322, 328 when the intermediate element 366 is positioned between the first and second rails 322, 328.
One or more first heating elements 340A preferably are positioned in the first gap 374, and one or more second heating elements 340B are positioned in the second gap 376.
It will also be understood that a non-oxidizing atmosphere preferably is provided, covering the first and second end faces 326, 334 and the first and second extension faces 307, 309. The region covered by the non-oxidizing atmosphere is identified by reference numeral 342 in
Next, the first heating elements 340A are energized, to heat the first end face 326 and a first length portion 346 of the first rail 322 extending from the first end face 326 into the first rail 322 to a predetermined hot working temperature, at which the first end face 326 and the first length portion 346 are plastically deformable (
Preferably, the second heating elements 340B are also energized, to heat the second end face 334 and a second length portion 348 of the second rail 328 extending from the second end face 334 into the second rail 328 to the predetermined hot working temperature, at which the second end face 334 and the second length portion 348 are plastically deformable (
In one embodiment, the intermediate element 366 preferably is subjected to transverse motion in one or more directions that are at least partially transverse to the intermediate element center line 367.
Preferably, while the intermediate element 366 is subjected to transverse motion thereof, and also while the first end face 326, the first length portion 346, the first extension face 307, the first intermediate element portion 311, the second end face 334, the second length portion 348, the second extension face 309, and the second intermediate element portion 313 are at the predetermined hot working temperature, the first and second end faces 326, 334 are engaged with the first and second extension faces 307, 309 respectively, to at least partially plastically deform the first end face 326, the first length portion 347, the first extension face 307, the first intermediate element portion 311, and also to at least partially plastically deform the second end face 334, the second length portion 348, the second extension face 309, and the second intermediate element portion 313.
Due to such plastic deformation, the first end face 326, the first length portion 346, the first extension face 307, and the first intermediate element portion 311 are fused together. In addition, and also due to such plastic deformation, the second end face 334, the second length portion 348, the second extension face 309, and the second intermediate element portion 313 are fused together, to form the fused rail assembly 320. The first end face 326, the first length portion 346, the first extension face 307, the first intermediate element portion 311, the second rail face 334, the second length portion 348, the second extension face 309, and the second intermediate element portion 313 are sometimes collectively or individually herein referred to as heated portions.
Preferably, the first rail 322 is moved in the direction indicated by arrow “3J” in
In one embodiment, the rails 322, 328 and the intermediate element 366 may all be subjected to respective transverse motions thereof while the heated portions are at the predetermined hot working temperature, and while the first and second end faces 226, 234 are engaged with the first and second contact surfaces 278, 280. The first and second rails 322, 328 may be subjected to transverse motion thereof relative to their respective center lines 324, 332. Alternatively, the rails 322, 328 may be subjected to transverse motions relative to their respective center lines 324, 332 alone, i.e., while the intermediate element 366 is stationary. The transverse motion of any of the elements may commence before or after engagement of the rails 322, 328 with the intermediate element 366.
As can be seen in
It will be understood that the intermediate element 366 may be provided without a plate portion thereof. The plate portion 386 may be included in the intermediate element 266, for instance, to facilitate positioning the intermediate element relative to the first and second rails 322, 328. Also, the plate portion 386 may be used to facilitate transverse movement of the intermediate element 366. If the intermediate element 366 includes a plate portion 366, then the plate portion 386 is at least partially removed by utilizing finishing processes as will be described.
Once the fused rail assembly 320 has been subjected to finishing processes to provide a modified or completed fused rail assembly 320′ (
As can be seen in
The excess top material 350 preferably is removed so that the head top surfaces 354A, 354B of the heads 323, 330 are unobstructed by the material 350, and are aligned (
As can be seen in
As can be seen in
Each of the extension portions 303, 305 extends axially from the body 301 of the intermediate element 366. It is believed that, because of the depth of the extension portions 303, 305, they provide a relative even distribution of heat therein when the heating elements 340A, 340B are energized. The extension portions 303, 305 preferably serve to control heat distribution, confining heat therein.
As noted above, the heating elements 340A, 340B may be configured to transfer additional heat energy to the heads 323, 330 of the rails 322, 328, upon energization of the heating elements 340A, 340B. For more even heat distribution, preheating may be utilized with respect to the parts of the extension portions 303, 305 that correspond to the heads 323, 330.
As can be seen in
As can be seen in
As can be seen in
It will be understood that replacement elements 437A, 437B, 437C are formed to at least partially fill the respective cavities 427A, 427B, 427C, and each of the replacement elements is formed to fit into a specific cavity. Preferably, each of the replacement elements 437A, 437B, 437C includes one or more engagement surfaces 439A, 439B, 439C that is shaped for engagement with the cavity wall of the cavity that the replacement element is intended to fill. Each of the replacement elements 437A, 437B, 437C preferably also includes one or more exterior surfaces 441A, 441B, 441C respectively. As will be described, each of the exterior surfaces 441A, 441B, 441C preferably is formed to be located in a predetermined position relative to the reference surfaces 429, 431, when the replacement element 437A, 437B, 437C fills the respective cavities 427A, 427B, 427C.
Preferably, each of the replacement elements 437A, 437B, 437C is positioned to locate the engagement surfaces 439A, 439B, 439C thereof spaced apart from the surfaces of the respective cavity walls to define respective gaps 443A, 443B, 443C therebetween (
Once the non-oxidizing atmospheres are in place, the heating elements are energized. In each of the examples illustrated in
Referring to
Preferably, the replacement element 437A, 437B, 437C is moved at least partially transversely relative to the rail center line 419 and then, while the replacement element is moving transversely, and while the heated portions are at the predetermined hot working temperature, the engagement surface thereof is engaged with the cavity wall. For example, in
Due to the transverse motion of the replacement element when the engagement surface engages the cavity wall in each case, the engagement surface of each respective replacement element and the cavity wall which the engagement surface is formed to engage are fused together, to form the repaired head portion 433 (
The repaired head portion 433 preferably is cooled, or allowed to cool, to an ambient temperature.
When the engagement surface is engaged with the cavity wall, a part of the heated portions may be squeezed outwardly, to be positioned on the crown surface 429 or the side face 431. This situation is illustrated in
As can be seen in
Those skilled in the art would appreciate that the excess top material 450 and the excess side material 452 may be removed by any suitable finishing process or processes. In the event that the exterior surface 441C is otherwise not satisfactorily aligned with the relevant reference surface therefor, suitable finishing processes may be applied to correct any misalignment.
It will be understood that the sequence in which certain steps of the embodiments of the method of the invention are performed may be varied without materially affecting the results produced by such embodiments.
It will also be appreciated by those skilled in the art that the invention can take many forms, and that such forms are within the scope of the invention as claimed. The scope of the claims should not be limited by the preferred embodiments set forth in the examples, but should be given the broadest interpretation consistent with the description as a whole.
This application claims the benefit of U.S. Provisional Patent Application No. 63/155,360, filed on Mar. 2, 2021, the entirety of which provisional application is hereby incorporated herein by reference.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/CA2022/050286 | 3/1/2022 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 63155360 | Mar 2021 | US |