Wild-type coil reinforcing bar and method for producing coil reinforcing bar

Abstract

The present invention provides, in one embodiment, a coil reinforcing bar in which a reinforcing bar is wound comprising longitudinal ribs formed in a longitudinal direction and transverse ribs formed at regular intervals along the longitudinal direction in a direction intersecting the longitudinal direction, wherein when a direction in which the coil reinforcing bar is wound is a first direction, a radial direction of the coil reinforcing bar is a second direction, and a height direction is a third direction, at least five reinforcing bars overlap from the outermost position in the second direction toward the third direction, and a rotation period (T, unit: mm) in which the longitudinal ribs make one rotation from the center of the reinforcing bar along the first direction, and a coil radius (R, unit: mm) satisfy the below relation. T > 1.2 × 2 × R × π

Description

Wild-type coiled rebar and coiled rebar production method

[0001] The present invention relates to a wild-type coiled reinforcing bar with wound reinforcing bars and a method for producing coiled reinforcing bars.

[0002] Reinforcing steel refers to steel rods used to reinforce the tensile strength of concrete structures that have nodes and ribs and have high adhesion to concrete, and may also be called deformed steel. Coiled steel refers to a coil product used to manufacture steel components embedded in concrete for reinforcement in the field of steel construction materials, and means a coil in which the above-mentioned reinforcing steel is wound.

[0003] Figure 1 shows a schematic diagram of reinforcing steel, and Figure 2 shows a schematic diagram of coiled steel.

[0004] The reinforcing bar (1) includes a longitudinal rib (2) extending in the longitudinal direction, which is the length direction of the reinforcing bar, and a transverse rib (3) extending in a direction intersecting the longitudinal rib (2). The transverse rib (3) is also called a node and is formed at regular intervals along the longitudinal direction.

[0005] The coiled reinforcing bar (10) is a reinforcing bar (1) that is wound up, and as shown in FIG. 2, the coiled reinforcing bar (10) is wound up by aligning it sequentially in the height direction, and this is called a compact type coiled reinforcing bar (10).

[0006] In the case of such coiled reinforcing bars (10), since reinforcing bars (1) are aligned and wound, equipment for winding while aligning is required, which has the limitation that production costs increase.

[0007] The present invention aims to solve the above problems by providing coiled reinforcing bars and reinforcing bars in which ribs are formed and wound, which are produced at a relatively low cost while having improved processability.

[0008] The problems of the present invention are not limited to those described above. A person skilled in the art to which the present invention pertains will have no difficulty understanding additional problems of the present invention from the overall contents of this specification.

[0009] To achieve the above objectives, the present invention provides the following wild-type coiled reinforcing bar and a method for producing coiled reinforcing bar.

[0010] In one embodiment, the present invention provides a coiled reinforcing bar having reinforcing bars wound thereon, wherein the reinforcing bars include longitudinal ribs formed in the longitudinal direction and transverse ribs formed at regular intervals along the longitudinal direction in a direction intersecting the longitudinal direction, wherein when the direction in which the coiled reinforcing bar is wound is the first direction, the radius direction of the coiled reinforcing bar is the second direction, and the height direction is the third direction, at least five reinforcing bars are overlapped from the outermost edge of the second direction to the third direction, and along the first direction, the rotation period (T, unit: mm) of the longitudinal rib rotating once from the center of the reinforcing bar and the radius of curvature (R, unit: mm) of the reinforcing bar satisfy the following relationship.

[0011] T > 1.2 × 2 × R × π

[0012] In one embodiment, the longitudinal rib in the reinforcing bar has an inclined angle (α) with respect to the length direction of the reinforcing bar, the position in the third direction according to the turn of the coil is non-uniform, and T may be smaller than 100,000 mm.

[0013] In one embodiment, the transverse rib may be orthogonal to the longitudinal rib or inclined to the longitudinal rib.

[0014] In one embodiment, the radius of the coil reinforcing bar may be 500 mm or more.

[0015] The present invention provides a method for producing coiled reinforcing bars, comprising: a heating step of heating a material in one embodiment; a forming step of rolling the heated material to form a wire rod, and forming the wire rod into a reinforcing bar by forming longitudinal ribs formed in the longitudinal direction and transverse ribs formed at regular intervals along the longitudinal direction in a direction intersecting the longitudinal direction; a winding step of winding the reinforcing bar with a laying head; a stacking step of stacking the wound reinforcing bar; and a twist correction step, after the forming step, of twisting the reinforcing bar in the opposite direction to the twisting that occurs in the winding step.

[0016] In one embodiment, the torsion correction step can be performed such that the rotation period (T, unit: mm) of the longitudinal rib rotating once from the center of the reinforcing bar in the coil reinforcing bar after the integration step and the coil radius (R, unit: mm) satisfy the following relationship.

[0017] T > 1.2 × 2 × R × π

[0018] The present invention can provide a wild-type coiled reinforcing bar in which ribs are formed through the above configuration, which is produced at a relatively low cost while having improved processability, and a method for producing the same.

[0019] The present invention can provide a coiled reinforcing bar that has less twisting in a coiled reinforcing bar that is wound without being aligned in the height direction, thereby reducing shape defects during field work.

[0020] Figure 1 is a schematic diagram of reinforcing steel.

[0021] Figure 2 is a schematic diagram of a coiled reinforcing bar.

[0022] Figure 3 is a schematic diagram of a wild-type coiled rebar.

[0023] Figure 4 is a schematic diagram of reinforcing steel unwound from a wild-type coiled reinforcing bar.

[0024] Figure 5 is a cross-sectional view of the reinforcing bar of Figure 4 at position II', and Figure 6 is a cross-sectional view of the reinforcing bar of Figure 4 at position II-II'.

[0025] Figure 7 is a perspective view of a part formed from the reinforcing steel of Figure 4.

[0026] FIG. 8 is a flowchart of a method for producing coiled reinforcing bars according to an embodiment of the present invention.

[0027] FIG. 9 is a perspective view of a coiled reinforcing bar according to an embodiment of the present invention.

[0028] FIG. 10 is a schematic diagram of a reinforcing bar unwound from a coiled reinforcing bar according to an embodiment of the present invention.

[0029] Figure 11 is a side view of the reinforcing bar of Figure 10.

[0030] Preferred embodiments of the present invention will be described below with reference to the attached drawings. However, embodiments of the present invention may be modified in various other forms, and the scope of the present invention is not limited to the embodiments described below.

[0031] In addition, embodiments of the present invention are provided to more fully explain the present invention to those with average knowledge in the relevant technical field.

[0032] In drawings, the shapes and sizes of elements may be exaggerated for clearer explanation.

[0033] In describing the embodiments of the present invention, if it is determined that a detailed description of known technology related to the present invention may unnecessarily obscure the essence of the present invention, such detailed description will be omitted. Furthermore, the terms described below are defined considering their functions in the present invention, and these may vary depending on the intentions or conventions of the user or operator. Therefore, such definitions should be based on the content throughout this specification. The terms used in the detailed description are merely for describing the embodiments of the present invention and should not be limited in any way. Unless explicitly stated otherwise, expressions in the singular form include the meaning of the plural form.

[0034] In this description, expressions such as “include” or “equipped” are intended to refer to certain characteristics, numbers, steps, actions, elements, parts or combinations thereof, and should not be interpreted to exclude the existence or possibility of one or more other characteristics, numbers, steps, actions, elements, parts or combinations thereof other than those described.

[0035] In this specification, terms such as 'top', 'upper', 'upper surface', 'lower', 'lower surface', 'lower surface', and 'side surface' are based on the drawings and may actually vary depending on the direction in which the elements or components are arranged.

[0036] Additionally, throughout the specification, when it is said that one part is 'connected' to another part, this includes not only cases where they are 'directly connected,' but also cases where they are 'indirectly connected' with other elements in between.

[0037] The present invention will be described in detail below through each embodiment or example of the invention. It should be noted that each embodiment or example described in this specification is not limited to a single embodiment or example, but may also be combined with other embodiments or examples. Accordingly, the citation of claims in the patent claims is merely an example of an embodiment, and the technical concept of the present invention should not be interpreted as being limited only to a combination with the cited claims; rather, combinations with various claims are also included within the scope of the technical concept of the present invention.

[0038] Figure 3 shows a wild-type coiled rebar, Figure 4 shows a schematic diagram of a reinforcing bar unwound from a wild-type coiled rebar, Figure 5 shows a cross-sectional view of the reinforcing bar of Figure 4 at position II', and Figure 6 shows a cross-sectional view of the reinforcing bar of Figure 4 at position II-II'.

[0039] Wild-type coiled reinforcing bars (10) are not wound while performing alignment as in FIG. 2, but rather the reinforcing bars (1) are continuously wound while passing through a laying head and rotating, and then accumulated to form a coil, so that the radius of curvature of the reinforcing bars (1) is produced uniformly. The reinforcing bars (1) are not sequentially aligned in the height direction. When viewed from the side, the wild-type coiled reinforcing bars (10) have five or more reinforcing bars (1) distributed among the reinforcing bars (1) arranged in the height direction that are offset by more than 50 mm in the radial direction based on the radius of curvature of the reinforcing bars (1) visible. That is, it means a coil formed by irregularly accumulating reinforcing bars (1) having the same radius of curvature.

[0040] Due to the rotation of the laying head, which is the conventional wire winding method, twisting occurs in the longitudinal ribs (2, see FIG. 1) of the reinforcing bar (1). The laying head winds while rotating, and the coil is wound one full turn per rotation.

[0041] For reference, since the laying head is disclosed in Korean Patent Publication No. 2010-0005844, a description of its structure will be omitted in this invention.

[0042] As shown in FIGS. 4 to 6, the longitudinal rib (2) formed in the longitudinal direction of the reinforcing bar (1) passes through the laying head and undergoes twisting that rotates around the center (C) of the reinforcing bar (1) along the longitudinal direction.

[0043] Due to the rotation of the laying head, that is, due to winding, the ribs (2, 3) of the reinforcing bar (1) are twisted in the longitudinal direction as shown in FIG. 4. This twisting period is the radius of curvature of the reinforcing bar formed by the laying head × 2 × π, that is, the length of one full rotation of the coiled reinforcing bar (10). For example, if the radius of curvature of the reinforcing bar is 0.5 m, the ribs (2, 3) rotate 360 ​​degrees as shown in FIG. 5 and 6 with a reinforcing bar length period of approximately 3.14 m.

[0044] Figure 7 shows a perspective view of a part formed from the reinforcing bar of Figure 4. The part (1') is formed by bending the reinforcing bar (1), and the part (1') of Figure 7 is formed by bending a straight reinforcing bar (1) at two places at 90° each to form a bent portion (5).

[0045] As shown in Fig. 7, when bending and forming with a reinforcing bar (1) that has twisted, a shape defect occurs where the bar is lifted from a plane due to the twisting during bending and forming. If such a defect occurs, it may result in errors in assembly at the construction site or make assembly itself impossible.

[0046] The present invention relates to a coiled rebar that can be produced through continuous winding of a laying head without causing shape defects during forming, a method for producing coiled rebar, and a reinforcing rebar unwound from the coiled rebar.

[0047] Based on the observation that defects in wild-type coiled reinforcing bars are caused by twisting during the winding process and not by other factors, such as cross-sectional shape or strength, the present invention performs torsion correction on the reinforcing bar in the direction opposite to the direction in which torsion occurs at any point from after the rib forming of the reinforcing bar is completed until before accumulation, thereby providing a coiled reinforcing bar with sufficiently relieved torsion and a reinforcing bar unwound from such a coiled reinforcing bar.

[0048] Figure 8 shows a flowchart of a method for producing coiled rebar, Figure 9 shows a perspective view of coiled rebar, and Figures 10 and 11 show a schematic diagram and a side view of a reinforcing bar with the coiled rebar unwound.

[0049] A method for producing coiled reinforcing bars according to one embodiment of the present invention comprises: a heating step (S110) of heating a material; a forming step (S120) of forming the heated material into a wire rod by rolling it, and forming the wire rod into a reinforcing bar by forming longitudinal ribs formed in the longitudinal direction and transverse ribs formed at regular intervals along the longitudinal direction in a direction intersecting the longitudinal direction; a first cooling step (S130) of cooling the formed reinforcing bar through a water cooling box; a winding step (S140) of winding the cooled reinforcing bar with a laying head; a second cooling step (S160) of air cooling the wound reinforcing bar while moving it; a stacking step (S170) of stacking the second-cooled reinforcing bar; and a twist correction step (S150) of correcting the twist of the reinforcing bar in the opposite direction of the twist occurring in the winding step after the forming step (S120).

[0050] The heating step (S110) is a step of heating a billet, and the material is not limited to a billet and various types of materials may be applied. The forming step (S120) is a step of forming the heated material into a wire rod through a rolling roll, and forming longitudinal and transverse ribs on the wire rod through a forming roll to form a reinforcing bar.

[0051] The first cooling step (S130) is a step of first cooling the high-temperature reinforcing steel by passing it through a water cooling box. In the first cooling step (S130), the material is made to have desired properties through heat treatment.

[0052] In the winding step (S140), the reinforcing bar that has been cooled once is wound through a laying head. The reinforcing bar wound in the winding step (S140) has the same shape as the shape of the wire rod being wound. In the winding step (S140), due to the rotation of the laying head, the ribs of the reinforcing bar are twisted around the longitudinal direction as shown in FIG. 4. This twisting period is radius of curvature × 2 × π, that is, the length of one full rotation of the coiled reinforcing bar (10).

[0053] After the winding step (S140) is completed, the wound wire is air-cooled while moving along a table, which is called the second cooling step (S160). After passing through the second cooling step (S160), it is collected by an accumulator, cut to have the required number of turns, and packaged to produce wild-type coiled rebar.

[0054] In the present invention, a twist correction step (S150) is performed to apply twist to the reinforcing bar after the forming step (S120) and before the accumulation step (S170). The twist correction step (S150) applies twist to the reinforcing bar either before or after the winding step (S140) in a direction opposite to the direction in which the twist is formed in the reinforcing bar, thereby mitigating the twist that occurs or is generated in the winding step (S140). The twist correction step applies reverse twist by rotating the reinforcing bar around the center (C; see FIG. 5) of the reinforcing bar. For example, reverse twist can be applied by passing the reinforcing bar through a mold or forming roll having a predetermined shape.

[0055] The period of twisting in the reinforcing bar can be extended due to the twist correction step (S150). In the twist correction step (S150), reverse twisting is applied so that the period (T) in the coiled reinforcing bar after assembly has a relationship with the coil winding radius R in the winding step (S140) as in Equation 1). As the period (T) increases, the twisting in the reinforcing bar decreases when the coiled reinforcing bar is unwound, so errors can be prevented when forming a part with the unwound reinforcing bar.

[0056] Equation 1) T > 1.2 × 2 × R × π

[0057] In this embodiment, the twist correction step (S150) is depicted as being performed after the winding step (S140), but it is not limited thereto, and as previously mentioned, it may be performed at any location after the forming step (S120) and before the integration step (S170).

[0058] The coiled reinforcing bar produced by the above-described production method is explained with reference to FIGS. 9 to 11. The coiled reinforcing bar (200) is formed by winding a reinforcing bar (100) that includes longitudinal ribs (110) formed in the longitudinal direction and transverse ribs (120) formed at regular intervals along the longitudinal direction in a direction intersecting the longitudinal direction. The direction in which the coiled reinforcing bar (200) is wound is designated as the first direction (D1), the radius direction of the coiled reinforcing bar (200) as the second direction (D2), and the height direction as the third direction (D3). In the present invention, the coiled reinforcing bar (200) is of the wild type, and when viewed from the second direction (D2), based on the radius of curvature of the reinforcing bar (100) visible, five or more reinforcing bars (100) are distributed among the reinforcing bars (100) arranged in the height direction that are offset by 50 mm or more in the second direction.

[0059] In the coil reinforcing bar (200), the reinforcing bar (100) has a period (T, unit: mm) which is the length of the reinforcing bar (100) that rotates once along the circumferential direction of the reinforcing bar (100) along the first direction (D1), but in this embodiment, the period (T) satisfies the relationship of Equation 1) previously mentioned, where the radius of curvature (R, unit: mm) of the reinforcing bar (100) in the coil reinforcing bar (200) is the radius of curvature.

[0060] Equation 1) T > 1.2 × 2 × R × π

[0061] In the production process of the coil reinforcing bar (200), the reinforcing bar (100) is wound with a radius of curvature (R) by a laying head, so the reinforcing bar (100) within the coil reinforcing bar (200) has a constant radius of curvature (R).

[0062] Meanwhile, the above period (T) may be smaller than 100,000 mm. In the present invention, it is possible to consider making the period (T) infinite, that is, completely eliminating torsion, but it may be easier to apply torsion correction through a simple structure rather than applying an additional laying head, and in this case, it is easier to alleviate torsion rather than completely eliminate it.

[0063] In one embodiment, the reinforcing bar (100) of the coil reinforcing bar (200) is shown as a bamboo type in which the transverse rib (120) is orthogonal to the longitudinal rib (110), but the present invention is not limited to a bamboo type and may be applied to a fishbone type in which the transverse rib (120) is inclined to the longitudinal rib (110), and may also be applied to other types of reinforcing bars.

[0064] If a separate torsion correction process is not performed during the process of unwinding the reinforcing bar (100) from the coiled reinforcing bar (200), the reinforcing bar (100) is straightened while maintaining the torsion, as shown in FIGS. 10 and 11. Looking at the reinforcing bar (100), the torsion is that the longitudinal rib (110) has an angle (α) inclined with respect to the length direction of the reinforcing bar (100), and as mentioned above, the period (T) in the coiled reinforcing bar (200) is equal to the length of the longitudinal rib (110) turning around the outer surface of the reinforcing bar (100) and returning to its original position. Therefore, the angle (α) inclined by the longitudinal rib (110) in the reinforcing bar (100) can satisfy the relationship of Equation 2) below. Here, r represents the radius (r, mm) of the reinforcing bar (100).

[0065] Equation 2 )2 × r × π / 100,000 < tan α < 2 × r × π / 4,000

[0066] When the radius (R) of the coil reinforcing bar (100) is 500 mm or more, the period (T) may be in the range of 4,000 to 100,000 mm, and the angle (α) may satisfy the relationship described above.

[0067] Although the present invention has been described above with reference to embodiments, it is understood that the invention is not limited thereto and can be implemented with various modifications.

[0068] [Explanation of the symbol]

[0069] 1, 100: Reinforcing steel

[0070] 10, 200: Coiled rebar

[0071] 2, 110: Longitudinal rib

[0072] 3, 120: Transverse rib

Claims

1. A wild-type coiled reinforcing bar having reinforcing bars wound thereon, comprising longitudinal ribs formed in the longitudinal direction and transverse ribs formed at regular intervals along the longitudinal direction in a direction intersecting the longitudinal direction, When the winding direction of the coiled rebar is the first direction, the radius direction of the coiled rebar is the second direction, and the height direction is the third direction, at least five reinforcing rebars overlap from the outermost point in the second direction to the third direction, and A wild-type coiled reinforcing bar in which, along the first direction, the rotation period (T, unit: mm) of the longitudinal rib rotating once from the center of the reinforcing bar and the coil radius (R, unit: mm) satisfy the following relationship. T > 1.2 × 2 × R × π 2. In Paragraph 1, In the above reinforcing bar, the longitudinal rib has an angle of inclination (α) inclined with respect to the length direction of the reinforcing bar, and The position in the second direction according to the turn of the coil is non-uniform, and The above-mentioned rotation period is a wild-type coiled rebar smaller than 100,000 mm.

3. In Paragraph 2, The above transverse rib is a wild-type coiled reinforcing bar orthogonal to the above longitudinal rib.

4. In Paragraph 2, The above transverse rib is a wild-type coiled reinforcing bar inclined with respect to the above longitudinal rib.

5. In Paragraph 3 or 4, Wild type coiled rebar with a radius of 500 mm or more.

6. In Paragraph 3 or 4, A wild-type coiled reinforcing bar having five or more reinforcing bars that are offset by 50 mm or more in the second direction, based on a reinforcing bar that shows a length greater than the radius of curvature of the reinforcing bar when viewed from the second direction.

7. Heating step for heating the material; A forming step of rolling the heated material to form a wire rod, and forming the wire rod into a reinforcing bar by forming longitudinal ribs formed in the length direction and transverse ribs formed at regular intervals along the length direction in a direction intersecting the length direction; A winding step of winding the reinforcing bar using a laying head; An accumulation step for accumulating wound reinforcing bars; and A method for producing coiled reinforcing bars, comprising: a twist correction step for correcting the twist of the reinforcing bar in the opposite direction of the twist occurring in the winding step after the forming step.

8. In Paragraph 7, A method for producing coiled rebar, wherein in the above-mentioned torsion correction step, the rotation period (T, unit: mm) of the longitudinal rib rotating once from the center of the reinforcing bar in the coiled rebar after the above-mentioned integration step and the coil radius (R, unit: mm) satisfy the following relationship. T > 1.2 × 2 × R × π

Images