Cold bending type steel bending equipment and process control method

Abstract

The application discloses a cold-bending type steel bending equipment and a process control method in the technical field of cold-bending type steel bending technology, and relates to a bending device which comprises a bending fixed roller and two bending movable rollers, wherein the bending movable rollers are synchronously moved relative to the bending fixed roller, a constraint device is applied to the end of a bending piece during a bending process, and different inner-arc-section bending rollers with different roller shapes are adopted when the steel is in a bending round cross section, a rectangular cross section or a U-shaped cross section, so that the rebound after bending is reduced, the bending curvature can meet the design requirements, and the end opening trend is reduced; the additional constraint device is applied to the end of the steel, so that the removal of the opening phenomenon is further ensured, the clamp is removed after the bending is completed, and the end shape is slightly opened or normal; and through the adjustment of the diameter, distribution position and movement track of the bending roller, the length of the unbending section at the head and tail of the bending piece is significantly reduced, the shape and size precision of the bending piece is improved, and the utilization rate of the raw material is improved.

Description

Technical Field

[0001] This invention relates to the field of longitudinal bending forming technology for irregular cross-section steel, specifically to a cold-bending steel bending equipment and process control method. Background Technology

[0002] With the rapid development of my country's economy and the rapid advancement of national infrastructure construction, the consumption of steel in the construction industry has increased rapidly. Cold-formed steel is a commonly used building material with huge market demand. However, under existing bending conditions, the production process of cold-formed steel suffers from problems such as large end openings, low dimensional accuracy, and large unbent sections at the beginning and end. Based on this, this invention designs a cold-formed steel bending equipment and process control method to solve the above problems. Summary of the Invention

[0003] The purpose of this invention is to provide a cold-bending steel bending equipment and process control method to solve the problems mentioned in the background art.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a cold-bending steel bending device, comprising a bending fixed roller and two bending moving rollers, wherein the bending moving rollers move synchronously relative to the bending fixed rollers, and a constraint device is applied to the end of the bent part during the bending process. For bending steel with circular, rectangular, and U-shaped cross sections, bending rollers with different inner arc segment shapes are adopted. A control model is constructed between the diameter of the bending moving rollers, the distance between the moving and fixed rollers, and the bending radius, which avoids the end of the bent part from opening up, large-scale springback after bending, and improves the length of the unbent section at the beginning and end of the bent part, thereby improving the overall bending accuracy and the utilization rate of raw materials.

[0005] Preferably, the inner arc bending roller adopts an arc-shaped roller surface; when bending rectangular cross-section steel, the inner arc bending roller adopts a square groove roller surface; when bending U-shaped cross-section steel, the inner arc bending roller adopts an "E" shaped roller surface.

[0006] Preferably, a constraint device is applied to the end of the rolled piece, such as... Figure 1 As shown, by applying a constraint device to the end of the rolled piece, the plastic deformation at the end of the rolled piece during bending deformation is controlled, thereby basically eliminating the end opening of the bent piece.

[0007] Preferably, the inner arc segment bending roller with irregular roller surface, such as Figure 2 As shown, the deformation constraint on the legs of the rolled piece is strengthened, which strictly restrains the high-axis swing of the legs in the middle section of the steel section during the bending process. Significant bending compression plastic deformation occurs in the inner arc section in the circumferential direction, reducing the rebound after bending. This ensures that the bending curvature meets the design requirements and reduces the tendency of the end to open up.

[0008] Preferably, the control of the bending roller's diameter, position, and movement trajectory is as follows: Figure 3 As shown, the working diameter of the bending roller is 108-216mm, and the number of rollers is set to 3. The positions of the two rollers are equidistant and adjustable on both sides of the center line of the bending fixed roller, and the adjustable center distance d of the bending moving roller is also shown. 12 =168~276mm, the movement trajectory of the two rollers is to maintain a fixed center distance and gradually approach the bending roller along the center line parallel to the bending roller, which increases the effective deformation range of the bending equipment, greatly reduces the length of the unbent section at the head and tail of the rolled piece, and improves the material utilization rate.

[0009] A cold-formed steel bending process, wherein the rotational angular velocities of the bending moving rollers 1 and 2 and the bending fixed roller 3 are related as shown in equation (1):

[0010]

[0011] In the formula, ω 12 The angular velocities of moving rollers 1 and 2 are expressed in rad·min. -1 ω3 is the angular velocity of the fixed roller, in rad·min. -1 ;D 12 D1 represents the diameter of moving rollers 1 and 2, in mm; D2 represents the diameter of fixed roller 3, in mm; R represents the bending radius, in mm; and a represents the horizontal bending width of the bent part, in mm.

[0012] Preferably, the radius R of the bending member is related to the distance d between the moving and fixed rollers and the diameter D of the moving roller. 12 Elastic modulus E, yield strength R p0.2 The mathematical model of the relationship between them is shown in equation (2):

[0013]

[0014] In the formula, the unit of elastic modulus E is GPa, and the yield strength R is... p0.2 The unit is MPa.

[0015] Preferably, the limiting bending radius R min The mathematical model is shown in equation (3):

[0016] R min = -0.0006D 12 3 +0.3618D 12 2 -72.344D 12 +5382.7 (3)

[0017] Compared with the prior art, the beneficial effects of the present invention are:

[0018] 1. By using an inner arc bending roller with a special-shaped roller surface, the high-axis swing of the leg of the middle section of the steel section is strictly constrained during the bending process, and significant bending compression plastic deformation occurs in the circumferential inner arc section, reducing the rebound after bending. This ensures that the bending curvature meets the design requirements and reduces the tendency of the end to open up.

[0019] 2. By applying an external constraint device to the end of the steel section, the opening phenomenon is further ensured to be eliminated. After bending is completed, the clamp is removed and the end shape is slightly open or normal.

[0020] 3. By adjusting the diameter, distribution position, and motion trajectory of the bending rollers, the length of the unbent sections at the beginning and end of the bent parts is significantly reduced, improving the shape and dimensional accuracy of the bent parts and increasing the utilization rate of raw materials.

[0021] Of course, any product implementing this invention does not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0022] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This invention relates to a rolling mill end constraint device.

[0024] Figure 2 The present invention relates to a square groove-shaped roller bending roller.

[0025] Figure 3 This invention relates to an "E"-shaped roller bending roller.

[0026] Figure 4 This invention relates to an arc-shaped roller bending roller.

[0027] Figure 5 This is the arrangement of the bending rollers in this invention.

[0028] Figure 6 This is a cross-sectional view of the steel profile of the present invention.

[0029] Figure 7 This is a schematic diagram of the bending process of the present invention. Detailed Implementation

[0030] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] Please see Figures 1 to 7 This invention provides a technical solution for cold-formed steel bending equipment and process control method: It includes a bending stationary roller and two bending moving rollers, a bending device in which the bending moving rollers move synchronously relative to the bending stationary roller, and a constraint device applied to the end of the bent part during the bending process. For bending steel with circular, rectangular, or U-shaped cross-sections, different inner arc-shaped bending rollers are used. A control model is constructed between the diameter of the bending moving roller, the distance between the moving and stationary rollers, and the bending radius, avoiding end opening of the bent part, significant springback after bending, and improving the length of the unbent section at the beginning and end of the bent part, thereby improving the overall bending accuracy and raw material utilization. The inner arc-shaped bending roller uses an arc-shaped roller surface; when bending rectangular cross-section steel, the inner arc-shaped bending roller uses a square groove roller surface; when bending U-shaped cross-section steel, the inner arc-shaped bending roller uses an "E"-shaped roller surface. A constraint device is applied to the end of the rolled part, the constraint device being as follows... Figure 1 As shown, by applying a constraint device to the end of the rolled piece, the plastic deformation at the end of the rolled piece during bending deformation is controlled, thereby basically eliminating the end opening of the bent piece.

[0032] An inner arc-shaped bending roller with an irregularly shaped roller surface, such as... Figure 2 As shown, the deformation constraint on the legs of the rolled piece is strengthened, which strictly restrains the high-axis sway of the legs in the middle section of the steel section during the bending process. Significant bending compression plastic deformation occurs in the circumferential inner arc segment, reducing the rebound after bending. This ensures that the bending curvature meets design requirements while reducing the tendency for the ends to open, controlling the diameter, position, and trajectory of the bending rolls, as shown. Figure 3 As shown, the working diameter of the bending roller is 108–216 mm, and the number of rollers is set to 3. The positions of the two rollers are equidistant and adjustable on both sides of the center line of the bending stationary roller, and the adjustable center distance d of the bending moving roller is also shown. 12 =168~276mm, the two rollers move along a fixed center distance and gradually approach the bending fixed roller along the center line parallel to the bending fixed roller, which increases the effective deformation range of the bending equipment, greatly reduces the length of the unbent section at the head and tail of the rolled piece, and improves the material utilization rate. The rotational angular velocity relationship between the bending moving rollers 1 and 2 and the bending fixed roller 3 is shown in equation (1):

[0033]

[0034] The radius R of the bent part and the distance d between the moving and stationary rollers, and the diameter D of the moving roller. 12Elastic modulus E, yield strength R p0.2 The mathematical model of the relationship between them is shown in equation (2):

[0035]

[0036] The mathematical model for the limiting bending radius is shown in equation (3):

[0037] R min = -0.0006D 12 3 +0.3618D 12 2 -72.344D 12 +5382.7 (3)

[0038] In the formula, the unit of elastic modulus E is GPa, and the yield strength R is... p0.2 The unit is MPa.

[0039] One specific application of this embodiment is: using U-shaped cross-section steel as raw material, with shape and dimensions as follows... Figure 6 As shown, the U-shaped section steel is bent and deformed using the three-roll bending equipment and process of this invention. The bending process is as follows: Figure 7 As shown, a restraint device (such as...) is applied to the ends of the steel section during the bending process. Figure 1 The rolls are arranged as follows: Figure 5 As shown, the number of bending work rollers is set to 3, where the bending moving roller that contacts the inner arc segment of the bent part is as follows: Figure 3 As shown, the diameter of the bending fixed roller 3 is 216mm, and the diameters of the bending moving rollers 1 and 2 are adjusted to 108mm. The positions of the moving rollers are equidistant and adjustable on both sides of the center line of the bending fixed roller. The adjustable center distance d of the bending moving rollers is... 12 =168mm. The two rollers move along a fixed center distance, gradually approaching the bending roller 3 parallel to the center line of the bending roller. When the distance between the moving and fixed rollers is maintained at d=207.48mm, bending production begins. After one-time forming, the product is inspected. The inspection results show that the shape and size of the bent part meet the product quality standards. By using the inner arc section bending roller with irregular roller surface, the high-axis swing of the leg of the middle section of the steel is strictly constrained during the bending process. Significant bending compression plastic deformation occurs in the circumferential inner arc section, reducing the rebound after bending. This ensures that the bending curvature meets the design requirements and reduces the tendency of the end to open. By applying an external constraint device to the end of the steel, the opening phenomenon is further ensured to be eliminated. After bending is completed, the clamp is removed, and the end shape is slightly open or normal. By adjusting the diameter, distribution position and movement trajectory of the bending rollers, the length of the unbent section at the head and tail of the bent part is significantly reduced, improving the shape and size accuracy of the bent part and improving the utilization rate of raw materials.

[0040] The product models provided by this invention are only for use based on the structural features of the product according to this technical solution. The products will be adjusted and modified after purchase to better match and conform to the technical solution of this invention. It is an optimal application of this technical solution. The product models can be replaced and modified according to the required technical parameters. This is well known to those skilled in the art. Therefore, those skilled in the art can clearly obtain the corresponding usage effect through the technical solution provided by this invention.

[0041] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0042] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A cold-bending steel bending device, characterized in that, The bending device includes a fixed bending roller and two moving bending rollers, wherein the moving bending rollers move synchronously relative to the fixed bending roller. During the bending process, a constraint device is applied to the end of the bent part. When bending steel with circular, rectangular, or U-shaped cross sections, bending rollers with different inner arc sections with different roller surface shapes are adopted. A control model is constructed between the diameter of the moving bending roller, the distance between the moving rollers, the distance between the moving and fixed rollers, and the bending radius. The two bending rollers are referred to as the first bending roller and the second bending roller, respectively. The relationship between the rotational angular velocities of the first bending moving roller, the second bending moving roller, and the bending stationary roller is shown in equation (1): (1) In the formula, ω 12 The angular velocities of the first and second bending rollers are expressed in rad·min⁻¹. ω 3 represents the angular velocity of the bending fixed roller, in rad·min⁻¹; D 12 The diameters of the first and second bending rollers are in mm. D 3 represents the diameter of the bending roller, in mm; R The bending radius is in mm. a The horizontal bending width of the bent component is expressed in mm. Bending radius R Spacing between moving and stationary rollers d Diameter of moving roller D 12 Elastic modulus E Yield limit R p0.2 The mathematical model of the relationship between them is shown in equation (2): (2) In the formula, the elastic modulus E The unit is GPa, yield strength. R p0.2 The unit is MPa; Limiting bending radius R min The mathematical model is shown in equation (3): (3)。 2. The cold-bending steel bending equipment according to claim 1, characterized in that, When bending circular cross-section steel, the inner arc bending roller uses an arc-shaped roller surface; when bending rectangular cross-section steel, the inner arc bending roller uses a square groove roller surface; when bending U-shaped cross-section steel, the inner arc bending roller uses an "E" shaped roller surface.

3. The cold-bending steel bending equipment according to claim 1, characterized in that, By applying a constraint device to the end of the rolled piece, the plastic deformation at the end of the rolled piece during bending deformation is controlled, thereby basically eliminating the end opening of the bent piece.

4. The cold-bending steel bending equipment according to claim 1, characterized in that, The inner arc section bending roll with irregular roller surface strengthens the deformation constraint on the legs of the rolled piece, so that the high-axis swing of the legs in the middle section of the steel section is strictly constrained during the bending process, and obvious bending compression plastic deformation occurs in the circumferential inner arc section, reducing the rebound after bending.

5. A cold-bending steel bending device according to claim 1, characterized in that, The parameters controlling the diameter, position, and movement trajectory of the bending rollers are set as follows: the working diameter of the bending rollers is 108~216 mm, the number of rollers is set to 3, the positions of the two rollers are equidistant and adjustable on both sides of the center line of the fixed bending roller, and the center distance of the moving bending roller is adjustable. d 12 =168~276 mm, the two rollers move along a fixed center distance and gradually approach the curved fixed roller along a line parallel to the center line of the curved fixed roller.

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