THREADED REBAR HOOP AND METHOD OF FORMING AND USE THEREOF
Threaded rebar with substantially continuous threads formed using a rolling process, wherein a majority of the circumference of the threaded rebar is covered by discontinuous threads, and wherein no additional steps are required to remove longitudinal ribs in the threaded rebar. The threaded rebar may be used to form threaded rebar hoops that utilize one or more threaded rebar sections and one or more couplings to mechanically couple the ends of the various threaded rebar sections. In such threaded rebar hoops, the external threads are able to engage a coupling, which has internal threads that engage the external threads on the threaded rebar. The mechanically coupled threaded rebar hoops are an improvement over the welded rebar hoops because the mechanically coupled threaded rebar hoops are easier and cheaper to manufacture, ship, and/or install on site, and/or may provide improved strength and/or manufacturability when compared to welded rebar hoops.
The present Application for a Patent claims priority to Provisional Application No. 62/377,348, entitled “Threaded Rebar Hoop and Method of Forming and Use Thereof,” filed Aug. 19, 2016, and assigned to the assignee hereof and hereby expressly incorporated by reference herein.
FIELDThe present invention is related to the field of threaded rebar, and more particularly threaded rebar hoops and methods of manufacturing and using the threaded rebar hoops.
BACKGROUNDReinforcing metal bars (hereinafter “rebar”) are bars, often made of steel, having protruding ribs, which are typically used to reinforce concrete structures. The protruding ribs can take a number of shapes or geometries, including diamond shaped, X-shaped, V-shaped, and the like. During the construction of bridges, buildings, and similar structures the rebar is often placed in a concrete form and concrete is poured around the rebar. The ribs in the rebar help to anchor the rebar within the concrete and add strength to the structures in which the rebar is used. In some applications of rebar, such as in columns (for example, columns for bridges, foundations for buildings, or the like), the rebar is formed into a hoop and welded to other rebar structures. In this regard, the rebar hoops may be tied to or affixed to longitudinally extending rebar (e.g., vertically or generally vertically rebar extending transverse to the rebar hoops) in order to form the columns.
In typical rebar manufacturing, heated bar stock is fed through rolls to form the cylindrical shaped rebar and protruding ribs. In some applications the ribs on the rebar can be manufactured and processed after forming the rebar in the rolls to create threads that extend around the periphery of the rebar. In one example, rebar may be formed, and after forming the rolled ribs may be machined, grinded, or otherwise removed in order to create the threaded ribs. Alternatively, threaded rebar can also be formed by rolling billets using three or more rollers (e.g., non-standard equipment), which does not require subsequent machining. In some embodiments threads (e.g., machined threaded, not ribbed threads formed from rolling) may actually be machined into standard rolled rebar. However, all of these methods of forming threaded rebar result in increased processing steps and/or non-standard equipment that increases the costs of forming threaded rebar products.
Standard rebar and threaded rebar can be manufactured by cold rolling or hot rolling metal billets. In both processes a billet is fed between two cylindrical rolls that form the billet into the rebar. The cylindrical rolls have grooves with notches (e.g., knurls) formed therein to receive a bar and form the core rebar shape and protruding ribs as the bar passes through the rolls. In some rebar manufacturing processes flat dies can replace the cylindrical rolls. The flat dies also have grooves with notches formed therein, and are spaced apart to receive a bar that is rotated between them in order to create threads or ribs along the length of the rebar or a portion thereof.
When threaded rebar is manufactured using cold rolling, the bar is passed through the rolls at temperatures below the recrystallization temperature of the metal, which increases the strength of the metal, improves the surface finish, and results in tighter tolerances on the rebar core and threaded ribs. However, cold rolling also causes work hardening of the metal, which results in the metal becoming brittle, and hence, more susceptible to cracking at the base of the formed threaded ribs. These cold rolling problems are exacerbated when threaded rebar is used with a coupling, and in these applications the cold rolled threaded rebar is susceptible to premature thread failure. In a hot rolling process the bar is passed through the rolls at temperatures above the recrystallization temperature of the metal, which prevents work hardening. Threaded rebar made from hot rolling results in threaded rebar having uniform tensile strength and elongation characteristics, as well as ribs that are less likely to crack because they are an integral part of the bar and not work hardened. Furthermore, hot rolling allows for the use of steels with higher tensile strength, and hot rolling processes do not require additional bar peeling or swaging of the threaded rebar. However, potential problems with threaded rebar manufactured through hot rolling include the formation of ribs that are coarse and that are unable to be used in applications requiring tight thread tolerances.
There are a number of problems associated with manufacturing threaded rebar using cylindrical rolls in a hot rolling process. Cylindrical rolls are used to form square, cylindrical, or other shaped bars into circular rebar with transverse threads formed into opposite sides of the circular rebar. The transverse threads formed are discontinuous and in some cases not aligned if the cylindrical rolls are not properly synchronized. Moreover, in these processes, two longitudinal ribs are formed along the length of the threaded rebar, which is a result of the excess metal from inconsistencies in the shape of the bar as well as the gap between the cylindrical rolls used to form the threaded rebar. The gap between the rolls is necessary so that the rolls do not rub against each other during the rolling process, since such rubbing may result in frictional heat that could damage the rolling system. The longitudinal ribs that result from processing prevent the threaded rebar from being freely rotatable within a nut or other mating internally threaded coupling. In order to manufacture threaded rebar without longitudinal ribs, additional steps are necessary that machine or shear off the longitudinal ribs. In some processes only the longitudinal ribs are machined off, however, in other processes the entire face of the bar with the longitudinal rib is machined into a flat surface. In still other processes the longitudinal ribs are sheared off using saw-tooth rotary dies, which are spaced apart to shear off sections of the longitudinal ribs located between the transverse ribs on the threaded rebar. In other processes the longitudinal ribs are ground off using a smooth groove rotary die that grinds down the longitudinal ribs. All of these methods present significant drawbacks, including additional processing steps, additional processing time, and additional processing equipment, all of which increase the cost of manufacturing the threaded rebar.
Alternatively, machined threads result in tight tolerances; however, machined threads are weaker than cold rolled threads. Moreover, manufacturing threaded rebar by machining the threads significantly increases the manufacturing costs associated with the threaded rebar, as it requires multiple processing steps, as well as being time consuming and resulting in higher handling expenses.
Therefore, there is a need to improve upon the formation of threaded rebar and the products made therefrom.
BRIEF SUMMARYEmbodiments of the present invention address the above needs and/or achieve other advantages by providing systems and methods that are used to create threaded rebar with substantially continuous threads using a rolling process, wherein a majority of the circumference of the threaded rebar is covered by the discontinuous threads; and wherein no additional steps are required to remove longitudinal ribs in the threaded rebar. Moreover, the threaded rebar may be used to form threaded rebar hoops that utilize one or more threaded rebar sections and one or more couplings to mechanically couple the ends of the various threaded rebar sections. In such threaded rebar, the external threads are able to engage a coupling (e.g., a nut, collar, or other apparatus), which has internal threads that engage the external threads on the threaded rebar. The mechanically coupled threaded rebar hoops are an improvement over the welded rebar hoops because the mechanically coupled threaded rebar hoops are easier and cheaper to manufacture, ship, and/or install on site, and/or may provide improved strength and/or manufacturability when compared to welded rebar hoops or other types of hoops.
Embodiments of the invention comprise a threaded rebar hoop. The threaded rebar hoop comprises a threaded rebar having a first end and a second end, wherein the threaded rebar is formed from a rolling process, wherein the threaded rebar is bent into a hoop shape, and wherein the threaded rebar is void of longitudinal ribs along at least the first end and the second end of the threaded rebar, and a coupling operatively coupling the first end and the second end of the threaded rebar to form the threaded rebar hoop.
In further accord with embodiments of the invention, the threaded rebar hoop comprises a stop operatively coupled to the coupling, the first end of the threaded rebar, or the second end of the threaded rebar.
In other embodiments of the invention, the coupling comprises a stop aperture, wherein the stop is operatively coupled to the stop aperture to reduce or prevent rotation of the coupling on the first end or the second end of the threaded rebar.
In still other embodiments of the invention, the coupling comprises an alignment feature, wherein the alignment feature is configured for aligning the first end and the second end within the coupling using the alignment feature.
In yet other embodiments of the invention, a first coupling end on the first end of the threaded rebar hoop is at least approximately the same length at the second coupling end on the second end of the threaded rebar hoop.
In further accord with embodiments of the invention, the first end or the second end has at least a straight portion on which the coupling is operatively coupled.
In other embodiments of the invention, the threaded rebar is formed without longitudinal ribs directly from the hot rolling process.
In still other embodiments of the invention, the hot rolling process comprises providing a lead pass bar comprising a body extending along a longitudinal axis, wherein at least one portion of the body has a cross-section defining a plane that intersects the longitudinal axis, wherein a first part of the plane has a first width, a second part of the plane has a second width, and a third part of the plane has a third width, wherein the first width is less than the second width and the third width, wherein the first part of the plane is located adjacent to the longitudinal axis, and the second part of the plane and third part of the plane are located distal from the longitudinal axis on opposite ends of the first part of the plane, wherein the lead pass bar has a X-axis through the first part of the plane, the second part of the plane and the third part of the plane, and a Y-axis through only the first part of the plane, and wherein the lead pass bar is formed in a first orientation along the longitudinal axis of the lead pass bar in one or more lead pass bar roll sets in which the X-axis is substantially parallel to and the Y-axis is substantially perpendicular to lead pass rolls of the one or more lead pass bar roll sets. The hot rolling processing further comprises forming the threaded rebar having substantially continuous threads from the lead pass bar by hot rolling the lead pass bar in one or more threaded rebar roll sets, wherein forming the threaded rebar comprises forming the threaded rebar from the lead pass bar in a second orientation along the longitudinal axis that is different from the first orientation in which the X axis is substantially perpendicular to and the Y-axis is substantially parallel to threaded rolls of the one or more threaded rebar roll sets, and wherein the threaded rebar is formed without having to remove longitudinal ribs along at least a portion of the body.
In yet other embodiments of the invention, the threaded rebar hoop is formed in a shape of a circular hoop, a square hoop, a rectangular hoop, an oval hoop, or a triangular hoop.
In further accord with embodiments of the invention, the threaded rebar is formed from two or more threaded rebar sections having at least one bend and two or more couplings, each of the two or more sections having the first end and the second end, wherein the first end of each section is operatively coupled the second end of each adjacent section through the coupling from the two or more couplings.
In other embodiments of the invention, the rebar has substantially continuous threads.
Another embodiment of the invention comprises a method of forming a threaded rebar hoop. The method comprises forming a threaded rebar from a rolling process, bending the threaded rebar, wherein the threaded rebar has a first end and a second end, and threading a coupling onto the first end of the threaded rebar hoop. The method further includes drawing the second end of the threaded rebar hoop adjacent to the first end of the threaded rebar hoop, and threading the coupling on the second end of the threaded rebar hoop.
In further accord with embodiments of the invention, the method comprises operatively coupling a stop to the coupling, the first end of the threaded rebar, or the second end of the threaded rebar.
In other embodiments of the invention, the coupling comprises a stop aperture, and wherein the method further comprises operatively coupling the stop within the stop aperture to reduce or prevent rotation of the coupling on the first end or the second end of the threaded rebar.
In still other embodiments of the invention, the rebar hoop comprises an alignment feature, wherein the method further comprising aligning the first end and the second end within the coupling using the alignment feature.
In yet other embodiments of the invention, threading the coupling on the second end of the threaded rebar hoop comprises threading the coupling until a first coupling end on the first end of the threaded rebar hoop is at least approximately the same length at the second coupling end on the second end of the threaded rebar hoop.
In further accord with embodiments of the invention, the threaded rebar is formed without longitudinal ribs directly from the hot rolling process.
In other embodiments of the invention, the threaded rebar is formed from two or more threaded rebar sections having at least one bend and two or more couplings, each of the two or more sections having the first end and the second end, wherein the first end of each section is operatively coupled the second end of each adjacent section through the coupling from the two or more couplings.
In still other embodiments of the invention, the rebar has substantially continuous threads.
In yet other embodiments of the invention, forming the threaded rebar comprises providing a lead pass bar comprising a body extending along a longitudinal axis, wherein at least one portion of the body has a cross-section defining a plane that intersects the longitudinal axis, wherein a first part of the plane has a first width, a second part of the plane has a second width, and a third part of the plane has a third width, wherein the first width is less than the second width and the third width, wherein the first part of the plane is located adjacent to the longitudinal axis, and the second part of the plane and third part of the plane are located distal from the longitudinal axis on opposite ends of the first part of the plane, wherein the lead pass bar has a X-axis through the first part of the plane, the second part of the plane and the third part of the plane, and a Y-axis through only the first part of the plane, and wherein the lead pass bar is formed in a first orientation along the longitudinal axis of the lead pass bar in one or more lead pass bar roll sets in which the X-axis is substantially parallel to and the Y-axis is substantially perpendicular to lead pass rolls of the one or more lead pass bar roll sets. Forming the threaded rebar further comprises forming the threaded rebar having substantially continuous threads from the lead pass bar by hot rolling the lead pass bar in one or more threaded rebar roll sets, wherein forming the threaded rebar comprises forming the threaded rebar from the lead pass bar in a second orientation along the longitudinal axis that is different from the first orientation in which the X axis is substantially perpendicular to and the Y-axis is substantially parallel to threaded rolls of the one or more threaded rebar roll sets, and wherein the threaded rebar is formed without having to remove longitudinal ribs along at least a portion of the body.
The features, functions, and advantages that have been discussed may be achieved independently in various embodiments of the present invention or may be combined in yet other embodiments, further details of which can be seen with reference to the following description and drawings.
Having thus described embodiments of the invention in general terms, reference will now be made to the accompanying drawings, wherein:
Embodiments of the present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all, embodiments of the invention are shown. Indeed, the invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like numbers refer to like elements throughout.
It should be understood that as illustrated in
It should be further understood that the shape of the threaded rebar hoops 1 in
It should be understood that the threaded rebar hoops 1 illustrated herein, specifically the circular threaded rebar hoops 1, may have a portion at the ends 5, 7 that is straight (e.g., not bent with a radius of curvature). Depending on the size of the threaded rebar hoops 1, the size of the couplings 10 (e.g., the length of the couplings 10), and the distance of travel of the couplings 10 along the threaded rebar sections 3 during assembly, the threaded rebar hoop ends 5, 7 may not be required to have a portion that is straight. In these cases the coupling 10 is sized for tolerances that would allow it to be coupled to slightly bent ends 5, 7 of the threaded rebar hoop 1. However, it is likely that at least a portion of the ends 5, 7 will not be bent so as to allow the couplings 10 to operatively couple the ends 5, 7 between one or more sections 3 of the threaded rebar hoop 1 together.
Block 104 of
Block 112 of
The stop 50 may be utilized to not only reduce or prevent movement of the coupling 10 during installation on site, but also during transportation, during which the vibrations from the transport could potentially cause the coupling 10 to rotate off (e.g., back-off, or the like) the first end 5 and/or second end 7 of the threaded rebar section 3. In some embodiments, the stop 50 is a self-drilling, self-threading and/or self-tapping fastener (e.g., screw, or the like), such that the fastener may form threads within the stop aperture 42 during assembly, in order to reduce or prevent the stop 50 from backing out of the stop aperture 42.
Block 114 of
It should be further understood that performing a welded connection between ends of rebar may be a difficult process to repeat, and thus, the strength of welded rebar hoops are dependent on the strength of the welds. As such, welded rebar hoops may require destructive testing by engineers, construction entities, or regulators before they can be utilized within a project. In some cases, 20 percent (or more or less depending on regulations) of the welded hoops may be required to undergo destructive testing in order to satisfy safety requirements for construction products, and thus, the threaded rebar undergoing destructive testing is useless for the construction product, which adds additional costs to the project. The threaded rebar hoops 1 of the present invention may provide improved strength and/or improved repeatability of the strength of the hoop at the coupling location, such that the destructive testing of the threaded rebar hoop 1 is not required, or at least the amount of testing may be reduced. As such, the improved strength and/or improved repeatability of the strength at the coupling location reduces the costs associated with the construction project.
It should be understood that the threaded rebar hoop 1 of the present invention may have improved strength of 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 35, 40, 45, 50, 70, 90, 100, 125, 150, 175, 200, 300, 400, 500, 600, 700, 800, 900, 1000, or more percent (or any range of percent improvement that falls within, overlaps, or is outside of these values) when compared to welded hoops.
It should be understood that typical rebar cage column construction may include operatively coupling longitudinal bars to the welded rebar hoops. The welded rebar hoops may be tied or welded to the outside and/or inside of longitudinal bars (e.g., vertical bars in the columns) of the rebar cage. The rebar cage columns may be formed on the ground and hoisted into place. For example, the hoops may be placed in frames and the longitudinal bars may be attached thereto. In some embodiments the rebar cages are formed in facilities and transported on site to be hoisted into place. In other embodiments the rebar hoops may be added to the structure as it is being built in the installed position. It should be understood that if the rebar hoops are not properly secured to the longitudinal bars the strength of the rebar cage could be greatly reduced before it is encapsulated in concrete, and thus portions of the rebar cage could fail and/or deform (e.g., which could cause structural problems if not identified before the concreate is added).
As previously discussed the threaded rebar hoops 1 of the present disclosure not only result in improved strength, but the rebar hoops may allow for improved installation processes that reduce costs. As such, the rebar hoops 1 may be used in the same way as welded rebar hoops (e.g., cages built at the factory or built on site, and hoisted into place), or the rebar hoops 1 of the present invention may partially or completely replace the welded rebar hoops 1. The rebar hoops 1 of the present disclosure may also be particularly useful when installing the rebar cages in place. For example, as the longitudinal rebar 502, 602 is being installed in the columns, the rebar hoops 1 may be placed around the longitudinal rebar 502, 602 at the desired locations. Moreover, regardless of the number of sections 3 used in the threaded rebar hoop 1 (e.g., one, two, three, or the like) the present invention may allow for adjusting the size of the hoops by making the ends of the sections 3 closer together and/or farther apart as the multiple sections are being assembled (e.g., in the rebar cage in the installed position, as a pre-assembly on site or at a manufacturing facility). In some cases, when installing the rebar hoops 1 on the outside of the longitudinal bars of a rebar cage column the ends of the rebar hoops 1 may be pulled together to provide a tighter fit around the longitudinal bars. Alternatively, when installing the rebar hoops 1 within the longitudinal rebar of the rebar cage, the ends of the sections 3 may be spaced apart (e.g., moved away from each other) when the one or more couplings 10 are used to provide a tighter fit within the rebar cage.
With respect to threaded rebar hoops having two or more sections 3 and two or more couplings 10, utilizing multiple sections 3 and assembling the rebar cages on site reduces shipping costs because the sections 3 may be bundled and shipped in smaller spaces and/or packages. The improved shipping costs may be especially true for large support columns for buildings and bridges, which may require oversized rebar hoops that may be difficult to transport to the construction site due to the limits of road clearances, and/or may be required to be assembled in the installed position because the pre-assembled columns may be not be able to be lifted into place. As such, in this way the threaded rebar sections 3 may be transported to the site in the bundles and assembled using couplings 10, and thereafter tied and/or welded to longitudinal bars.
While
Moreover, not only may the couplings 10 described herein be utilized with the rebar hoops 1 of the rebar cages, but the couplings 10 may also be utilized to operatively couple the longitudinal bars of the rebar cages together and/or to operatively couple other portions of the rebar cages together, where one end of a first threaded rebar meets another end of a threaded rebar. As such, the couplings 10 and/or the rebar hoops 1 described herein may be utilized in combination with other rebar cage elements to create a rebar cage system that is cheaper to manufacture (e.g., through the threaded rebar forming process described below), cheaper to ship (e.g., components may be more easily bundled and shipped), stronger (e.g., the couplings 10 provide a more reliable strength determination over the plurality of rebar hoops), cheaper and faster to assemble (e.g., less destructive testing is needed, can be more quickly installed, and because it is stronger less rebar hoops 1 are need because they can be spaced farther apart), and/or more flexible installation (e.g., the rebar hoops 1 can be assembled as the structure is being built instead of pre-assembled).
With respect to forming the threaded rebar sections 3 described herein, the threaded rebar sections 3 may be formed by first rolling (e.g., cold rolling or hot rolling) a billet 200 into a lead pass bar 220, rotating the lead pass bar 220 to a different orientation, and rolling the lead pass bar 220 into the threaded rebar 240, as illustrated in
In the present invention, the threaded rebar sections 3 can be produced using conventional rebar processing equipment and without the additional steps and tooling that are used for removal of the longitudinal ribs 262. Therefore, it is generally not necessary to use more than two rolls or more than two dies at a time to create the substantially continuous threaded rebar 240, or to use little to no additional machining, grinding, or shearing operations to remove a portion of the longitudinal ribs 262. The present invention results in threaded rebar 240 that can be used to create the threaded rebar sections 3 for the threaded rebar hoops 1 described herein utilizing standard rebar manufacturing tooling and equipment in less time and for less cost than conventional threaded rebar products made utilizing more complex manufacturing processes and equipment.
It should be understood that after the cross-sectional area of the billet 200 is reduced to the proper size, the hot roll lead pass rolls 300 shapes the billet 200 into a lead pass bar 220 with the proper cross-sectional area for producing a threaded rebar product without longitudinal ribs. The type of cross-sectional area of the lead pass bar 200 will impact the surface quality and circular cross-section of the final threaded rebar 240. If a lead pass bar 220 with the proper cross-sectional area is not used, excess material can build up between the gaps in the rolls and create longitudinal ribs 262 in the threaded rebar 240, as illustrated by the rebar product 260 in
In order to create threaded rebar 240 with little to no longitudinal ribs 262, a bar with a reduced width (see B of
It should be understood that typical threaded rebar 260 that includes longitudinal ribs 262, as illustrated in
The dimensions and shape of the cross-sectional area of the lead pass bar 220 play a role in producing threaded rebar 240 with little to no longitudinal ribs 262.
As previously discussed the shape of the lead pass bar 220 illustrated in
In the embodiment illustrated in
In order to create the hourglass lead pass bar 220, the rectangular billet 200 is fed through a lead pass roll system 300 that has opposing rolls, as illustrated in
The rectangular billet 200 as illustrated in
A threaded pass roll system 350, which has two opposing rolls, is used in order to manufacture the threaded rebar 240, as illustrated in
As illustrated in
Another feature of the threaded rebar 240 produced using this lead pass bar 220 is that there are little to no longitudinal ribs 262 that run along the surface of the threaded rebar 240 in the longitudinal direction, or at least along a partial length of the threaded rebar 240. As illustrated in
Along with the dimensions of the lead pass bar 220, the gap distance (see G), may also play an important role in preventing longitudinal ribs from forming along the length of the threaded rebar 240. The shape of the lead pass bar 220, as well as the gap distance, helps to prevent the metal from filling the gaps 370 between the first threaded roll 352 and the second threaded roll 354, thus preventing longitudinal ribs 262 from forming in the present invention. If the gap is too small, material may fill the gap and form longitudinal ribs 262, or alternatively, if the gap is too large the threaded rebar 240 may not form the proper cylindrically shaped core or threads.
As illustrated by
Different types of threaded rebar 240 can be produced by simply changing the dimensions of the grooves 310, 360 and knurls 362 in the lead pass rolls 302, 304 and threaded pass rolls 352, 354, as well as the gaps between the rolls. These changes can be made to create customized lead pass bars 220 that result in customized threaded rebar 240 with little to no longitudinal ribs 262 based on the individual requirements of each customer, through an interchangeable and cost effective process utilizing standard rebar forming tooling and equipment.
In some embodiments as previously discussed above, instead of changing the orientation of the lead pass bar in order to roll the lead pass bar through the threaded pass roll set to form the threaded rebar, the threaded pass roll set may be oriented 90 degrees with respect to the lead pass bar roll set. Alternatively, three or more rollers may be utilized instead of two rollers to form the threaded rebar product. In still other embodiments, threads may be machined into the rebar.
It should be understood that “operatively coupled,” when used herein, means that the components may be formed integrally with each other, or may be formed separately and coupled together. Furthermore, “operatively coupled” means that the components may be formed directly to each other, or to each other with one or more components located between the components that are operatively coupled together. Furthermore, “operatively coupled” may mean that the components are detachable from each other, or that they are permanently coupled together.
Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation. In addition, where possible, any terms expressed in the singular form herein are meant to also include the plural form and/or vice versa, unless explicitly stated otherwise. Accordingly, the terms “a” and/or “an” shall mean “one or more.”
Specific embodiments of the invention are described herein. Many modifications and other embodiments of the invention set forth herein will come to mind to one skilled in the art to which the invention pertains, having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the invention is not to be limited to the specific embodiments disclosed and that modifications and other embodiments and combinations of embodiments are intended to be included within the scope of the appended claims. As such, it will be understood that, where possible, any of the advantages, features, functions, devices, and/or operational aspects of any of the embodiments of the present invention described and/or contemplated herein may be included in any of the other embodiments of the present invention described and/or contemplated herein, and/or vice versa.
Claims
1. A threaded rebar hoop, the threaded rebar hoop comprising:
- a threaded rebar having a first end and a second end, wherein the threaded rebar is formed from a rolling process, wherein the threaded rebar is bent into a hoop shape, and wherein the threaded rebar is void of longitudinal ribs along at least the first end and the second end of the threaded rebar; and
- a coupling operatively coupling the first end and the second end of the threaded rebar to form the threaded rebar hoop.
2. The threaded rebar hoop of claim 1, further comprising:
- a stop operatively coupled to the coupling, the first end of the threaded rebar, or the second end of the threaded rebar.
3. The threaded rebar hoop of claim 2, wherein the coupling comprises a stop aperture, wherein the stop is operatively coupled to the stop aperture to reduce or prevent rotation of the coupling on the first end or the second end of the threaded rebar.
4. The threaded rebar hoop of claim 1, wherein the coupling comprises an alignment feature, wherein the alignment feature is configured for aligning the first end and the second end within the coupling using the alignment feature.
5. The method of claim 3, wherein a first coupling end on the first end of the threaded rebar hoop is at least approximately the same length at the second coupling end on the second end of the threaded rebar hoop.
6. The threaded rebar hoop of claim 1, wherein the first end or the second end has at least a straight portion on which the coupling is operatively coupled.
7. The threaded rebar hoop of claim 1, wherein the threaded rebar is formed without longitudinal ribs directly from the hot rolling process.
8. The threaded rebar hoop of claim 7, wherein the hot rolling process comprises:
- providing a lead pass bar comprising a body extending along a longitudinal axis, wherein at least one portion of the body has a cross-section defining a plane that intersects the longitudinal axis, wherein a first part of the plane has a first width, a second part of the plane has a second width, and a third part of the plane has a third width, wherein the first width is less than the second width and the third width, wherein the first part of the plane is located adjacent to the longitudinal axis, and the second part of the plane and third part of the plane are located distal from the longitudinal axis on opposite ends of the first part of the plane, wherein the lead pass bar has a X-axis through the first part of the plane, the second part of the plane and the third part of the plane, and a Y-axis through only the first part of the plane, and wherein the lead pass bar is formed in a first orientation along the longitudinal axis of the lead pass bar in one or more lead pass bar roll sets in which the X-axis is substantially parallel to and the Y-axis is substantially perpendicular to lead pass rolls of the one or more lead pass bar roll sets; and
- forming the threaded rebar having substantially continuous threads from the lead pass bar by hot rolling the lead pass bar in one or more threaded rebar roll sets, wherein forming the threaded rebar comprises forming the threaded rebar from the lead pass bar in a second orientation along the longitudinal axis that is different from the first orientation in which the X axis is substantially perpendicular to and the Y-axis is substantially parallel to threaded rolls of the one or more threaded rebar roll sets, and wherein the threaded rebar is formed without having to remove longitudinal ribs along at least a portion of the body.
9. The threaded rebar hoop of claim 1, wherein the threaded rebar hoop is formed in a shape of a circular hoop, a square hoop, a rectangular hoop, an oval hoop, or a triangular hoop.
10. The threaded rebar hoop of claim 1, wherein the threaded rebar is formed from two or more threaded rebar sections having at least one bend and two or more couplings, each of the two or more sections having the first end and the second end, wherein the first end of each section is operatively coupled the second end of each adjacent section through the coupling from the two or more couplings.
11. The threaded rebar hoop of claim 1, wherein the rebar has substantially continuous threads.
12. A method of forming a threaded rebar hoop, the method comprising:
- forming a threaded rebar from a rolling process;
- bending the threaded rebar, wherein the threaded rebar has a first end and a second end;
- threading a coupling onto the first end of the threaded rebar hoop;
- drawing the second end of the threaded rebar hoop adjacent to the first end of the threaded rebar hoop; and
- threading the coupling on the second end of the threaded rebar hoop.
13. The method of claim 12, further comprising:
- operatively coupling a stop to the coupling, the first end of the threaded rebar, or the second end of the threaded rebar.
14. The method of claim 12, wherein the coupling comprises a stop aperture, wherein the method further comprising:
- operatively coupling the stop within the stop aperture to reduce or prevent rotation of the coupling on the first end or the second end of the threaded rebar.
15. The method of claim 12, wherein the rebar hoop comprises an alignment feature, wherein the method further comprising:
- aligning the first end and the second end within the coupling using the alignment feature.
16. The method of claim 12, wherein threading the coupling on the second end of the threaded rebar hoop comprises threading the coupling until a first coupling end on the first end of the threaded rebar hoop is at least approximately the same length at the second coupling end on the second end of the threaded rebar hoop.
17. The method of claim 12, wherein the threaded rebar is formed without longitudinal ribs directly from the hot rolling process.
18. The method of claim 12, wherein the threaded rebar is formed from two or more threaded rebar sections having at least one bend and two or more couplings, each of the two or more sections having the first end and the second end, wherein the first end of each section is operatively coupled the second end of each adjacent section through the coupling from the two or more couplings.
19. The method of claim 12, wherein the rebar has substantially continuous threads.
20. The method of claim 12, wherein forming the threaded rebar comprises:
- providing a lead pass bar comprising a body extending along a longitudinal axis, wherein at least one portion of the body has a cross-section defining a plane that intersects the longitudinal axis, wherein a first part of the plane has a first width, a second part of the plane has a second width, and a third part of the plane has a third width, wherein the first width is less than the second width and the third width, wherein the first part of the plane is located adjacent to the longitudinal axis, and the second part of the plane and third part of the plane are located distal from the longitudinal axis on opposite ends of the first part of the plane, wherein the lead pass bar has a X-axis through the first part of the plane, the second part of the plane and the third part of the plane, and a Y-axis through only the first part of the plane, and wherein the lead pass bar is formed in a first orientation along the longitudinal axis of the lead pass bar in one or more lead pass bar roll sets in which the X-axis is substantially parallel to and the Y-axis is substantially perpendicular to lead pass rolls of the one or more lead pass bar roll sets; and
- forming the threaded rebar having substantially continuous threads from the lead pass bar by hot rolling the lead pass bar in one or more threaded rebar roll sets, wherein forming the threaded rebar comprises forming the threaded rebar from the lead pass bar in a second orientation along the longitudinal axis that is different from the first orientation in which the X axis is substantially perpendicular to and the Y-axis is substantially parallel to threaded rolls of the one or more threaded rebar roll sets, and wherein the threaded rebar is formed without having to remove longitudinal ribs along at least a portion of the body.
Type: Application
Filed: Aug 16, 2017
Publication Date: Feb 22, 2018
Inventors: Francis W. Griggs (Indian Springs, AL), Tim Andrew Patterson (Blytheville, AR), Delbert A. Benzenhafer, JR. (Lighthouse Point, FL)
Application Number: 15/678,754