Post-processing equipment for rolled strip

Abstract

The invention discloses post-processing equipment for a rolled strip, relates to the technical field of strip rolling post-processing, and aims to solve the problems of waved edge warping and overall warping caused by non-uniform residual stress distribution of edge and central areas after a metal strip is rolled in the prior art. Comprising a gradient annealing device and an edge stress grading regulation and control device, the gradient annealing device at least comprises a plurality of heating roller groups; the plurality of heating roller groups are arranged at equal intervals along the moving direction of the strip, each heating roller group comprises two heating rollers, the two heating rollers respectively heat the upper surface and the lower surface of the rolled strip, each heating roller at least comprises a magnetic induction coil, and the coil density of the magnetic induction coil is gradually reduced from the edge part to the middle part; the edge stress grading regulation and control device at least comprises a plurality of edge pressing roller sets arranged in the strip moving direction. The included angle between each edge pressing roller set and the width direction of the strip is gradually reduced in the moving direction of the strip. The method is used for realizing precise regulation and control of the residual stress.

Description

Technical Field

[0001] The present invention relates to the technical field of post - processing of strip rolling, and particularly relates to a post - processing device for rolled strips. Background Art

[0002] During the rolling process of metal strips, due to factors such as elastic deformation of rolls, uneven material flow, and temperature distribution differences, non - uniform residual stress distributions are easily formed in the edge and central regions of the strip, resulting in defects such as edge wavy warping and overall warping of the rolled strip. Such defects not only affect the surface flatness and dimensional accuracy of the strip, but also reduce the qualified rate of subsequent deep processing, becoming a problem restricting the production of high - precision metal strips.

[0003] Existing technologies mostly use annealing processes to regulate the residual stress of rolled strips. Traditional annealing uses an overall uniform heating method. Although it can partially eliminate the residual stress, it cannot specifically release the stress difference between the edge and central regions, resulting in the edge wave problem being difficult to completely solve. And traditional mechanical straightening technology applies external forces to the strip through a roller straightening machine to force it to be flattened. It can only temporarily correct the geometric shape of the strip and does not eliminate the internal residual stress, making the warping likely to recur in subsequent processing. Summary of the Invention

[0004] The purpose of the present invention is to provide a post - processing device for rolled strips, which is used to solve the problems of edge wavy warping and overall warping caused by uneven residual stress distribution between the edge and central regions after metal strip rolling in the prior art, and to achieve precise regulation of residual stress.

[0005] To achieve the above purpose, the present invention provides the following technical solutions: In a first aspect, the present invention provides a post - processing device for rolled strips, including: a gradient annealing device and an edge stress hierarchical regulation device; the outlet end of the gradient annealing device is connected to the inlet end of the edge stress hierarchical regulation device; The gradient annealing device at least includes a plurality of heating roller groups; the plurality of heating roller groups are arranged at equal intervals along the moving direction of the strip. Each heating roller group includes two heating rollers, and the two heating rollers respectively heat the upper surface and the lower surface of the rolled strip; each heating roller at least includes a magnetic induction coil, and the coil density of the magnetic induction coil decreases from the edge to the middle. The edge stress hierarchical regulation device at least includes a plurality of edge - pressing roller groups arranged along the moving direction of the strip; each edge - pressing roller group includes four edge - pressing roller wheels; the angle between each edge - pressing roller group and the width direction of the strip gradually decreases along the moving direction of the strip.

[0006] Optionally, each heating roller further includes a support roller core, an inner roller sleeve, an outer roller sleeve, and two end caps; The supporting roller core is located at the center of the roller body of the heating roller; the material of the supporting roller core is ceramic insulating material; The inner roller sleeve is sleeved on the outside of the supporting roller core, and the outer roller sleeve is sleeved on the outside of the inner roller sleeve, and a heating roller cavity is formed between the inner roller sleeve and the outer roller sleeve; The magnetic induction coil is wound around the outer surface of the inner roller sleeve, and high-frequency alternating current is passed through both ends of the magnetic induction coil; The two end covers are respectively fixed to the two ends of the roller body of the heating roller.

[0007] Optionally, the gradient annealing device further includes: a plurality of temperature acquisition devices; each of the temperature acquisition devices is connected to one of the heating rollers; the temperature acquisition device includes a sensor base and at least three temperature sensors fixed on the sensor base; the at least three temperature sensors are evenly distributed along the axial direction of the heating roller.

[0008] Optionally, the gradient annealing device further comprises an upper box, a lower box and a tension roller group; The upper box body and the lower box body are connected to form a closed cavity; The tension roller group is arranged at the entrance of the closed cavity.

[0009] Optionally, the tension roller group includes a first tension roller, a second tension roller and a third tension roller; The first tension roller and the second tension roller are at the same level; the third tension roller is located below the first tension roller and the second tension roller.

[0010] Optionally, the gradient annealing device further comprises a heat dissipation device; the heat dissipation device is arranged above the plurality of heating rollers; The heat dissipation device includes a heat dissipation box, multiple cooling motors and multiple fans; the heat dissipation box is provided with grid-shaped heat dissipation holes; A plurality of cooling motors are arranged on the heat dissipation box; The plurality of fans are installed inside the heat dissipation box; Each of the cooling motors is connected to one of the fans.

[0011] Optionally, the gradient annealing device further includes a protective gas tank and at least one nozzle, the protective gas tank and the at least one nozzle are both arranged on the upper box body, and the at least one nozzle is connected to the protective gas tank.

[0012] Optionally, the edge stress grading control device further comprises a main box, an upper pressing plate, a lower pressing plate and two telescopic connecting rod mechanisms; The main box is a U-shaped frame consisting of a bottom plate and two side plates; The upper pressing plate and the lower pressing plate are both arranged between the two side plates, and an inlet and an outlet for the strip are arranged on each side plate; Each telescopic link mechanism includes a plurality of telescopic link pairs, a guide plate, a ball screw seat, a ball screw, and a driving motor; Both the upper pressing plate and the lower pressing plate are connected to each telescopic link pair, and each telescopic link pair is also connected to the guide plate; The guide plate is also connected to the first end of the ball screw seat, the second end of the ball screw seat is connected to the first end of the ball screw, and the second end of the ball screw is connected to the driving motor.

[0013] Optionally, each edge pressing roller includes: a flange seat, a rod shaft, a roller, and a set screw; the roller is fixed to the upper pressing plate or the lower pressing plate through the flange seat; the flange seat is sleeved outside the rod shaft; threaded holes are provided at the upper end of the flange seat and the rod shaft, and the rod shaft is locked by assembling the set screw to fix the angle of the edge pressing roller.

[0014] Optionally, the edge stress grading and regulating device further includes a plurality of first heat preservation boxes arranged on the upper pressing plate and a plurality of second heat preservation boxes arranged on the lower pressing plate; one first heat preservation box and one second heat preservation box are arranged between two adjacent edge pressing roller groups.

[0015] The beneficial effects of the present invention are as follows: Compared with the prior art, the present invention provides a post-processing device for a rolled strip. In the embodiment of the present invention, the magnetic induction coil of the heating roller in the gradient annealing device is used to achieve non-uniform and gradient heating, and the edge pressing rollers with graded angles in the edge stress grading and regulating device are used to apply graded stress to the rolled strip, constructing a composite regulation mechanism of coordinated heat release and force, accurately targeting the residual stress difference between the edge and the center of the strip, overcoming both the uniformity defect of traditional annealing and the stress residue problem of mechanical straightening, reducing warping defects from the root cause, and improving the flatness and processing stability of the strip. Description of the Drawings

[0016] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings: Figure 1 is a schematic diagram of the overall structure of a post-processing device for a rolled strip provided by an embodiment of the present invention; Figure 2 is a schematic diagram of the overall structure of a strip processing device provided by an embodiment of the present invention; Figure 3Schematic structural diagram of the gradient annealing device provided by an embodiment of the present invention; Figure 4 Schematic structural diagram of the heating roller provided by an embodiment of the present invention; Figure 5 Schematic cross-sectional structural diagram of the heating roller provided by an embodiment of the present invention; Figure 6 Schematic structural diagram of the edge stress grading and control device provided by an embodiment of the present invention; Figure 7 Schematic diagram showing the angles between multiple pressing roller groups and the moving direction of the strip provided by an embodiment of the present invention; Figure 8 Schematic structural diagram of the temperature acquisition device provided by an embodiment of the present invention; Figure 9 Schematic structural diagram of the heat dissipation device provided by an embodiment of the present invention; Figure 10 Schematic cross-sectional structural diagram of the pressing roller provided by an embodiment of the present invention; Figure 11 Schematic structural diagram of the pressing roller provided by an embodiment of the present invention; Reference numerals: 1 - gradient annealing device; 2 - edge stress grading and control device; 11 - heating roller; 111 - magnetic induction coil; 112 - support roller core; 113 - inner roller sleeve; 114 - outer roller sleeve; 115 - end cover; 116 - heating roller cavity; 12 - temperature acquisition device; 121 - sensor base; 122 - temperature sensor; 13 - upper box body; 14 - lower box body; 15 - tension roller group; 151 - first tension roller; 152 - second tension roller; 153 - third tension roller; 16 - heat dissipation device; 161 - heat dissipation box body; 162 - cooling motor; 163 - fan; 17 - protective gas tank; 18 - nozzle; 21 - pressing roller group; 211 - first pressing roller; 212 - second pressing roller; 213 - third pressing roller; 214 - fourth pressing roller; 215 - flange seat; 216 - rod shaft; 217 - roller; 218 - set screw; 219 - threaded hole; 22 - main box body; 221 - bottom plate; 222 - first side plate; 223 - second side plate; 23 - upper pressing plate; 24 - lower pressing plate; 241 - second insulation box; 25 - telescopic connecting rod pair; 251 - first connecting rod; 252 - second connecting rod; 26 - guide plate; 27 - ball screw seat; 28 - ball screw; 29 - driving motor. Detailed implementation manners

[0017] For the convenience of clearly describing the technical solutions of the embodiments of the present invention, in the embodiments of the present invention, terms such as "first" and "second" are used to distinguish identical or similar items with basically the same functions and effects. For example, the first threshold and the second threshold are only used to distinguish different thresholds, and do not limit their sequence. Those skilled in the art can understand that terms such as "first" and "second" do not limit the quantity and execution order, and terms such as "first" and "second" do not necessarily limit being different.

[0018] It should be noted that in the present invention, words such as "exemplary" or "for example" are used to indicate examples, illustrations or explanations. Any embodiment or design solution described as "exemplary" or "for example" in the present invention should not be construed as being more preferred or having more advantages than other embodiments or design solutions. Rather, the use of words such as "exemplary" or "for example" is intended to present relevant concepts in a specific manner.

[0019] In the present invention, "at least one" means one or more, and "a plurality" means two or more. "And / or" describes the association relationship of associated objects and indicates that three relationships may exist.

[0020] As Figure 1 shown, the embodiments of the present invention provide a post-processing device for a rolled strip, which may include: a gradient annealing device 1 and an edge stress grading and regulating device 2, and the outlet end of the gradient annealing device 1 is connected to the inlet end of the edge stress grading and regulating device 2; see Figure 2 , it can be understood that the post-processing device for the rolled strip in this embodiment is connected to a rolling device and is used for post-processing the rolled strip; the rolling device rolls the inlet strip, and the rolled strip enters the post-processing device for further processing and outputs the outlet strip; The gradient annealing device 1 includes a plurality of heating roll groups; the plurality of heating roll groups are arranged at equal intervals along the moving direction of the strip, see Figure 3 , each heating roll group includes two heating rolls 11, and the two heating rolls respectively heat the upper surface and the lower surface of the rolled strip, so that both the upper and lower surfaces of the rolled strip can be uniformly annealed; see Figure 4 and Figure 5 , each heating roll 11 includes at least a magnetic induction coil 111, and the coil density of the magnetic induction coil 111 decreases from the edge to the middle, that is, the coil density of the magnetic induction coil 111 decreases from any one of the two edges where the two ends of the heating roll are located to the middle, and the coil density is symmetrically distributed along the axial center of the heating roll; See Figure 6, the edge stress grading and control device 2 at least includes a plurality of edge pressing roller groups 21 arranged along the moving direction of the strip; each edge pressing roller group 21 includes four edge pressing rollers, or rather, each edge pressing roller group includes a first edge pressing roller 211, a second edge pressing roller 212, a third edge pressing roller 213, and a fourth edge pressing roller 214; the first edge pressing roller 211 and the second edge pressing roller 212 are symmetrically arranged along the center line in the width direction of the strip, and the third edge pressing roller 213 and the fourth edge pressing roller 214 are symmetrically arranged along the center line in the width direction of the strip; the first edge pressing roller 211 and the third edge pressing roller 213 are symmetrically arranged vertically in the thickness direction of the strip; the second edge pressing roller 212 and the fourth edge pressing roller 214 are symmetrically arranged vertically in the thickness direction of the strip; See Figure 7 , the angle between each edge pressing roller group and the width direction of the strip gradually decreases along the moving direction of the strip. It can be understood that, along the width direction of the strip, the four angles between the axial directions of the four edge pressing rollers in each edge pressing roller group and the width direction of the strip are the same. For example Figure 7 in, the angles between the axial directions of the edge pressing rollers in the first ( Figure 7 the first stage in) edge pressing roller group and the width direction of the strip are all 15 0 , the second ( Figure 7 the second stage in) edge pressing roller group, the angles between the axial directions of the edge pressing rollers and the width direction of the strip are all 10 0 , the third ( Figure 7 the third stage in) edge pressing roller group, the angles between the axial directions of the edge pressing rollers and the width direction of the strip are all 5 0 , the fourth ( Figure 7 the fourth stage in) edge pressing roller group, the angles between the outer normal directions of the edge pressing rollers and the moving direction of the strip are all 0 0 .

[0021] It can be understood that in the field of strip processing, the width direction is a commonly used term, referring to the transverse dimension perpendicular to the moving direction of the strip (i.e., the length direction); for example: when the strip is conveyed, its advancing direction is the length direction (i.e., the moving direction of the strip), the horizontal direction perpendicular to the advancing direction is the width direction, and the direction perpendicular to the strip plane is the thickness direction. The center line in the width direction refers to an imaginary straight line that bisects the width of the strip in the width direction of the strip. This imaginary straight line is parallel to the length direction and is equidistant from the left and right edges of the strip.

[0022] It can be said that the angle between each edge pressing roller group and the width direction of the strip refers to the acute angle between the axial direction of any one edge pressing roller in each edge pressing roller group and the width direction of the strip. Or, it can also be said that the angle between each edge pressing roller group and the moving direction of the strip refers to the acute angle between the outer normal of any one edge pressing roller in each edge pressing roller group and the moving direction of the strip. The angle sizes in these two cases are the same.

[0023] After rolling, the edge of the strip is a free surface, and the transverse stress relaxes. , but due to the temperature difference between the edge and the middle of the strip, residual tensile stress is generated. .

[0024] During the process of the strip passing through the edge pressing roller (such as the first edge pressing roller 211), the axial rotation of the first edge pressing roller 211 will provide a stress to the strip along the moving direction of the roller. , and this stress can be divided into the rolling direction stress. and the transverse stress. , Pointing to the inside direction of the strip, it can effectively balance part of the residual tensile stress. The formula is as follows: (1) In formula (1), is to regulate the transverse residual stress at the front edge; is the regulation amount of the transverse stress at the edge; is the actual transverse residual stress after regulation.

[0025] By grading and regulating the edge pressing roller groups at multiple different angles along the moving direction of the strip, the residual tensile stress at the edge is gradually reduced. By reasonably controlling the transverse compressive stress, the edge stress distribution is optimized; it should be noted that the regulation amount of the transverse compressive stress needs to be reasonably controlled according to the actual situation to prevent the residual tensile stress from turning into residual compressive stress and affecting the surface quality of the strip.

[0026] The beneficial effects of this implementation are analyzed as follows: First, there is a gradient annealing device in the post-processing equipment of the strip after rolling, which has the following advantages: 1) Two heating roller groups are arranged symmetrically up and down. The two symmetric heating roller groups up and down ensure the overall heating uniformity of the strip after rolling, avoiding the "one-size-fits-all" problem of traditional annealing. At the same time, the uneven stress distribution is eliminated through local temperature differences; 2) The magnetic induction coil density of each heating roller decreases from the edge to the middle, that is, the magnetic induction coil density is high at the edge and low in the middle → the heating power at the edge is higher → the temperature of the strip edge is higher than the central area → using the temperature gradient to make the thermal expansion of the edge material more significant, and specifically releasing the residual stress at the edge (because the edge usually bears greater tensile stress during rolling); Generally speaking, compared with traditional overall annealing, the stress difference between the edge and the center can be more accurately regulated, and defects such as edge waves can be reduced.

[0027] Second, an edge stress grading and regulating device is provided in the post-processing equipment for the rolled strip. Two sets of edge pressing roller groups are symmetrically distributed along the center line of the strip width. For the multiple edge pressing rollers in each roller group, the angle between their axial direction and the strip width direction gradually decreases in the strip moving direction, which has the following advantages: 1) Graded mechanical stress application: The gradually decreasing angle → the compressive stress of the rollers on the strip edge gradually decreases along the moving direction → simulating a progressive stress release process; 2) Coordination of edge plastic deformation: By applying different degrees of compressive stress to the edge through multiple sets of rollers, controllable plastic deformation is generated in the edge material to offset the tensile stress accumulated during rolling, while avoiding material damage caused by excessive pressure from a single roller; 3) Synergistic correction of stress and geometry: Combining with the temperature field after gradient annealing, the mechanical compressive stress further promotes the release of edge residual stress, realizing the dual regulation of "thermal-mechanical coupling". Generally speaking, compared with traditional mechanical straightening, it not only corrects the geometric shape, but also eliminates internal residual stress by applying graded stress, reducing the risk of defect recurrence.

[0028] Third, the gradient annealing device combined with the edge stress grading and regulating device realizes the thermal-mechanical coupling regulation process. First is the gradient annealing pretreatment: releasing the concentrated stress at the edge through the temperature gradient, reducing the material hardness and stress level; then is the graded mechanical straightening: on the basis of thermal annealing, using the angle gradient of the edge pressing rollers to further coordinate the stress states of the edge and the center, realizing the precise matching of residual stress. The combination of the gradient annealing device and the edge stress grading and regulating device has the following advantages: 1) Traditional methods only rely on thermal regulation or force regulation alone. The present invention designs a thermal-mechanical synergistic regulation method to solve the non-uniform stress problem from the two dimensions of "stress release" and "stress reconstruction"; 2) The two-dimensional gradient design (temperature gradient and angle gradient) makes the regulation process more conform to the stress distribution characteristics of the strip, improving the pertinence and effectiveness of governing the deficiencies of the existing technology.

[0029] All in all, the embodiment of the present invention constructs a composite regulation mechanism of "thermal release + force coordination" through the non-uniform and gradient heating of gradient annealing and the graded stress application of the edge pressing rollers, precisely aiming at the residual stress difference between the strip edge and the center. It not only overcomes the uniformity defect of traditional annealing, but also makes up for the stress residue problem of mechanical straightening, reducing warping defects at the source and improving the flatness and processing stability of the strip.

[0030] Optionally, as Figure 4 shown and Figure 5 shown, each heating roller 11 further includes a support roller core 112, an inner roller sleeve 113, an outer roller sleeve 114 and two end caps 115; The support roller core 112 is located at the center of the roller body of the heating roller 11; The support roller core 112 is made of insulating materials such as ceramics; The inner roll sleeve 113 is sleeved outside the support roll core 112, and the outer roll sleeve 114 is sleeved outside the inner roll sleeve 113. A heating roll cavity 116 is formed between the inner roll sleeve 113 and the outer roll sleeve 114; The magnetic induction coil 111 is wound around the outer surface of the inner roll sleeve 113, and high-frequency alternating current is applied to both ends of the magnetic induction coil 111; Two end covers 115 are respectively fixed to both ends of the roll body of the heating roll 11.

[0031] Furthermore, the materials of both the inner roll sleeve 113 and the outer roll sleeve 114 are metal materials; the metal surface of the inner roll sleeve 113 provides a support carrier for the magnetic induction coil; a heat-conducting medium can be filled in the heating roll cavity 116 between the inner roll sleeve 113 and the outer roll sleeve 114 to optimize the heat conduction efficiency. The heat-conducting medium can fill the coil gap through convection or heat conduction, diffuse the locally concentrated heat to the entire roll sleeve surface, reduce the "hot spot" phenomenon, and ensure a more uniform temperature distribution along the axis of the outer roll sleeve. The heat-conducting medium (such as insulating oil) has both insulation and heat dissipation properties, can prevent the coil from aging or short-circuiting due to high temperature, and at the same time carry away the Joule heat generated by the resistance of the coil itself, avoiding overheating and damage of the coil (long-term high temperature of the coil is likely to cause the failure of the insulating layer of the enameled wire). After filling the heat-conducting medium, the magnetic induction coil is fixed in the cavity between the inner roll sleeve and the outer roll sleeve, reducing the relative movement between the coil and the roll sleeve during high-speed rotation and reducing the risk of wear.

[0032] Optionally, the heat-conducting medium in the heating roll cavity 116 can be heat-conducting oil or high-thermal-conductivity insulating silicone grease. Compared with air, these two heat-conducting media can greatly reduce the thermal resistance, quickly conduct the heat of the inner roll sleeve to the outer roll sleeve, and improve the overall thermal response speed.

[0033] High-frequency alternating current is applied to both ends of the magnetic induction coil 111, and the inner metal roll sleeve is heated by the Joule heat effect generated by the eddy current flowing through the conductor. The heating effect is more significant where the coil is wound more densely, realizing a decreasing temperature from the edge to the middle of the roll surface, and compensating for the residual stress concentration caused by the rapid temperature drop at the edge of the rolled strip after rolling.

[0034] In this embodiment, the heating roller generates heat through the electromagnetic induction effect, and realizes the differential heating of the strip edge and the central region by combining the density gradient distribution of the magnetic induction coils. The specific principle is as follows: First, adopt the electromagnetic induction heating mechanism: the magnetic induction coil is energized with high-frequency alternating current → an alternating electromagnetic field is generated → eddy currents are induced inside the inner roller sleeve and the outer roller sleeve (metal material) → the eddy currents generate heat to raise the temperature of the roller body → the strip surface is heated through heat conduction. Second, achieve gradient heating: the density of the magnetic induction coils decreases from the edge to the middle of the heating roller (more turns at the edge and fewer turns in the middle). In the edge region with a high coil density, the intensity of the alternating electromagnetic field is higher → the induced eddy current is stronger → the heat generation is greater. In the middle with a low coil density of the coil → the heat generation is less, and a gradient distribution with a high temperature at the edge and a low temperature in the middle is formed on the surface of the heating roller. When contacting the (rolled) strip, the strip edge absorbs more heat, and the heat in the central region is relatively less, thus realizing non-uniform heating. Third, the upper and lower symmetric heating roller groups work together: the upper and lower heating roller groups apply gradient heat synchronously → temperature gradients are formed in the corresponding regions on the upper and lower surfaces of the strip → avoiding thermal deformation caused by unilateral heating, and at the same time enhancing the symmetry and uniformity of the edge stress release to compensate for the residual stress concentration caused by the rapid temperature drop at the strip edge after rolling. It can be further understood by combining the following specific formula (2): (2) Wherein, is the Poisson's ratio of the strip material; is the coefficient of thermal expansion; is the elastic modulus of the strip material; is the thermal stress term (temperature difference between the edge and the middle); is the stress in the rolling direction; is the transverse stress; is the stress in the thickness direction. The strip edge is a free surface, and the transverse stress relaxes , but due to the temperature difference between the strip edge temperature and the middle temperature, residual tensile stress may be generated. The greater the temperature difference, the more likely it is to cause residual stress concentration at the edge. By compensating for the temperature drop at the strip edge through the magnetic induction coils with different coil densities in the heating roller and promoting the release of edge residual stress, the phenomena such as edge waves and warping of the strip after rolling can be effectively improved.

[0035] The heating roll in this embodiment has the following structural features: 1) A multi-layer nested roll body design (support roll core + inner roll sleeve + outer roll sleeve). Among them, the support roll core provides mechanical strength support to prevent the roll body from deforming due to heating expansion or external forces; the inner roll sleeve and the outer roll sleeve form an independent heating cavity, isolating the magnetic induction coil in the cavity to prevent the coil from directly contacting the strip and causing short circuits or wear, and at the same time evenly conducting heat through the metal roll sleeve; the end cover seal is used to fix the roll body structure, prevent dust and impurities from entering the cavity and affecting the coil performance, and improve the reliability of the equipment. 2) An external layout of the magnetic induction coil (wound around the outer surface of the inner roll sleeve): The coil is not embedded inside the roll body. During maintenance, the outer roll sleeve can be directly disassembled and replaced, reducing maintenance costs; by adjusting the ratio of the number of turns of the coil at the edge to the middle, the temperature gradient amplitude can be flexibly changed to adapt to the stress regulation requirements of different specifications of strips. 3) The eddy current excited by the high-frequency current is concentrated on the surface layer of the roll sleeve (skin effect), with a fast heating response speed, and the heat generation amount can be real-time controlled by adjusting the current frequency or intensity to achieve dynamic temperature adjustment. 4) The support roll core is made of non-metallic materials such as ceramics, which plays a supporting role and prevents potential safety hazards caused by current flowing through the box body during energization.

[0036] The traditional heating roll is a resistance heating roll with uniform heating. Compared with the traditional heating roll, the heating roll and its heating method in this embodiment are as follows: 1) The traditional annealing is uniformly heated and cannot solve the stress concentration at the edge. In this embodiment, the magnetic induction coil density gradient design, more heat generation at the edge and less heat generation in the middle, form a temperature gradient, and specifically heat the edge to release stress. 2) The structure of the traditional heating equipment is complex and difficult to maintain. In this embodiment, a multi-layer nested modular design (support roll core + inner / outer roll sleeve + end cover), the components are detachable, and the coil maintenance does not require the entire roll body to be replaced. 3) The heating temperature control accuracy of the traditional heating roll is low. In this embodiment, the coil is driven by high-frequency alternating current, the temperature distribution is adjustable, and the temperature gradient can be quantitatively controlled with high control accuracy; 4) The heating efficiency of the traditional heating roll is low and the energy consumption is high. In this embodiment, electromagnetic induction heating directly acts on the metal roll sleeve → the heat conversion efficiency exceeds 90% (about 60 - 70% for traditional resistance heating).

[0037] As can be seen from the above content, the heating roll structure in this embodiment combines gradient heating design with a modular mechanical structure, systematically solving the deficiencies of the traditional annealing process in terms of stress regulation accuracy, equipment maintainability, and energy consumption efficiency, and improving the accuracy of post-processing of metal strips.

[0038] Optionally, referring to Figure 8 , the gradient annealing device further includes: a plurality of temperature acquisition devices 12; each temperature acquisition device 12 is connected to a heating roll 11; the temperature acquisition device 12 includes a sensor base 121 and at least three temperature sensors 122 fixed on the sensor base 121; for example, three temperature sensors 122 are evenly distributed.

[0039] For exampleFigure 8 As shown, each heating roller 11 is connected to three temperature sensors 122, and the three temperature sensors 122 are evenly distributed along the axial direction of the heating roller. The temperature sensors 122 at both ends are used to collect the temperatures at both ends of the heating roller 11, and the temperature sensor 122 in the middle is used to collect the temperature at the middle part of the heating roller. It should be noted that when arranging the temperature sensors 122, they generally do not directly contact the roller surface of the heating roller. Since the temperature of the roller surface is high, it is easy to directly burn out the sensor by exceeding the threshold. The distance between the head of the sensor and the roller surface is approximately 1 mm, and the approximate temperature is measured.

[0040] Traditional annealing devices usually only configure 1-2 temperature sensors. In most cases, it is single-point monitoring (for example, only 1 sensor is set in the middle of the heating roller or at a fixed position near the heat source). In a few scenarios, 1 sensor may be set at each end (2 in total), but the distribution density is low and lacks regularity. Such a sensor setting method has limited monitoring range, low control accuracy, and weak fault tolerance. In this embodiment, three evenly distributed temperature sensors are adopted, which have the following advantages: First, 1 temperature sensor is set at each of the two ends and the middle of the heating roller to form a basic monitoring network of 'two ends + midpoint', which can directly capture the following key information: 1) Axial temperature gradient: By comparing the data of the sensors at both ends and the middle, it can be judged whether there are abnormalities such as overheating in the middle, overcooling at both ends, or one end being too high / low of the heating roller (such as the edge effect that is difficult to detect by traditional devices); 2) Symmetry verification: If the difference in data between the two end sensors exceeds the threshold, it can quickly identify problems such as faults in the heating elements on the left and right sides of the heating roller or uneven heat dissipation (such deviations cannot be located by the traditional single-point scheme). For example, assuming the length of the heating roller is 1 meter, the monitoring error of the traditional single-point monitoring may reach ±5°C (only measuring the midpoint, and the actual temperatures at both ends are unknown), while the three-point uniform distribution can control the overall temperature monitoring error within ±2°C, and can directly quantify the gradient value (such as 'left end 200°C → midpoint 220°C → right end 210°C', the gradient is low on the left, high in the middle, and right is biased towards the middle). Second, the three sensors form a minimum redundant network. When any 1 fails, the remaining 2 data can still support the operation of the system (such as estimating the midpoint temperature only using the data at both ends, or judging the gradient trend only using the data of the midpoint and one end), avoiding the risk of shutdown caused by traditional single-point failures. Third, the three sensors can divide the heating roller into three control regions of 'left - middle - right'. The system independently adjusts the heating power at the corresponding position according to the real-time data of each region, avoiding the lag of the traditional 'one-size-fits-all' global approach. For example, when the left-end sensor detects that the temperature is 20°C lower than the set value, the system only increases the power of the left-end heating element, while the middle and right ends maintain the original parameters, and the response time is shortened by more than 50% compared with the traditional scheme (without waiting for the temperature to conduct to the midpoint before adjustment). Fourth, by comparing the differences in the data of the three sensors (such as the temperature difference between the two ends should be <5°C under normal conditions, if it suddenly expands to 15°C), it can directly point to faults in the heating elements, heat conduction obstacles (such as scaling), or poor sensor contact in the corresponding region, and the maintenance efficiency is increased by more than 70% (the traditional scheme needs to check section by section). Fifth, gradient annealing requires a specific temperature gradient to be formed on the surface of the material (such as the temperature increasing along the running direction). The three sensors can directly verify whether the designed gradient is achieved (such as left end 200°C → midpoint 250°C → right end 300°C, error ±3°C), while the traditional single-point scheme cannot provide gradient data and can only rely on experience for adjustment.

[0041] Optionally, referring to Figure 2 , the gradient annealing device 1 further includes an upper box body 13, a lower box body 14, and a tension roller group 15; After the upper box body 13 and the lower box body 14 are connected, a closed cavity is formed; The tension roller group 15 is arranged at the entrance of the closed cavity; the tension roller group 15 is used to tension the rolled strip entering the gradient annealing device.

[0042] In this embodiment, the tension roller group is arranged at the entrance of the closed cavity to tension the rolled strip entering the gradient annealing device. The reason is as follows: When the rolled strip enters the heating roller without tension, it may become loose, sag or locally stack due to its own weight or uneven roller body friction. For example, the strip in the wrinkled area does not contact the heating roller sufficiently, resulting in abnormal local temperature (such as insufficient heating or overheating), and regional differences in the material properties (such as hardness and flatness) after annealing; The rolled strip without tension control is prone to lateral deviation (such as running off), which may deviate from the effective action range of the heating roller, resulting in the annealing process being unable to completely cover the strip surface, and even causing equipment scratching, tearing and other failures.

[0043] The advantage of setting the tension roller group in this embodiment is that it can provide a constant tension force for the rolled strip. One is to ensure that the strip maintains a straight movement trajectory and avoid deviation, wrinkling or stacking; the second is to make the strip closely fit the heating roller to ensure the heat conduction efficiency and the uniformity of temperature distribution; the third is to cooperate with the speed control system to achieve precise matching of the annealing time and temperature gradient. The design of the tension roller group in this embodiment is aimed at the quality fluctuation problem caused by out-of-control tension in the traditional annealing device, and lays a foundation for the subsequent gradient annealing process through the pre-tensioning mechanism, especially suitable for high-end materials with high requirements for flatness and performance uniformity.

[0044] Furthermore, referring to Figure 3 , the tension roller group 15 may include a first tension roller 151, a second tension roller 152 and a third tension roller 153; the first tension roller 151 and the second tension roller 152 are horizontally at the same height; the third tension roller 153 is vertically located below the first tension roller 151 and the second tension roller 152, and the third tension roller 153 is horizontally located between the first tension roller 151 and the second tension roller 152. The three tension rollers act together to tension the strip and adjust the entrance height of the strip, which is convenient for subsequent edge stress control.

[0045] Specifically, the advantages of setting three tension rollers are as follows: 1) The first tension roller and the second tension roller are horizontally at the same height, which can provide uniform initial tension in the transverse direction of the strip, ensuring that the strip is evenly stressed in the width direction and avoiding situations such as deviation and wrinkles. The third tension roller is located below and cooperates with the former two to apply tension to the strip in the vertical direction. Acting together in two-dimensional directions, the overall tension of the strip is more stable. For example, when processing a wider metal strip, uniform stress in the transverse direction can prevent the edges of the strip from wrinkling, and the tension in the vertical direction can prevent the strip from sagging; 2) This layout forms a specific strip running path, which can effectively guide the strip to smoothly enter subsequent components such as heating rollers. The strip shuttles between the three tension rollers, and its running trajectory is restricted, reducing the possibility of strip shaking and deviation, ensuring that the strip accurately enters the annealing area, and improving the consistency of annealing quality. For example, on a continuous annealing production line, a stable running trajectory can ensure that the strip is evenly heated throughout the annealing process; 3) By adjusting parameters such as the spacing and rotation speed between the three tension rollers, the tension on the strip can be flexibly adjusted. For example, when processing strips of different thicknesses and materials, the settings of the tension rollers can be changed accordingly to meet the tension requirements of different strips; for thinner and easily deformable foil materials, the tension can be appropriately reduced; for thicker and more rigid strips, the tension can be increased. This adjustability enhances the adaptability of the equipment to different strips; 4) This layout of the three tension rollers is relatively compact, occupying less equipment space, which is conducive to the overall miniaturization design of the equipment, and at the same time has good structural stability. During operation, the cooperating layout can effectively disperse the acting force generated by the strip tension, reduce the stress burden on individual components, and extend the service life of the equipment.

[0046] Optionally, referring to Figure 3 , the gradient annealing device 1 further includes a heat dissipation device 16; the heat dissipation device 16 is arranged above the plurality of heating rollers 11; referring to Figure 9 , the heat dissipation device 16 includes a heat dissipation box body 161, a plurality of cooling motors 162 and a plurality of fans 163; the heat dissipation box body 161 is provided with grid-shaped heat dissipation holes; the plurality of cooling motors 162 are arranged on the heat dissipation box body 161; the plurality of fans 163 are all installed inside the heat dissipation box body 161; each cooling motor 162 is connected to a fan 163 or directly connected.

[0047] The temperature sensor sends the detected temperature information to the controller in the post-processing equipment of the strip after rolling. When the temperature information indicates that the temperatures at both ends of the heating roller exceed the set threshold, the controller controls the fan to discharge the heat on the roller surface through the heat dissipation holes, reducing the roller surface temperature. The controller can be set at a certain part of the upper box body 13.

[0048] Optionally, referring to Figure 3, the gradient annealing device 1 further includes a protective gas tank 17 and at least one nozzle 18. The protective gas tank 17 and the at least one nozzle 18 are both arranged on the upper box body 13, and the at least one nozzle 18 is connected to the protective gas tank 17. The protective gas tank 17 passes the protective gas into the closed cavity formed by the upper box body 13 and the lower box body 14 through the nozzle 18. The protective gas is an inert gas such as argon to prevent the strip from being oxidized during the annealing process.

[0049] Optionally, referring to Figure 6 , in addition to including a plurality of edge pressing roller groups 21, the edge stress grading and control device 2 further includes: a main box body 22, an upper pressing plate 23, a lower pressing plate 24, and two telescopic link mechanisms; it should be noted that for each edge pressing roller group 21, the first edge pressing roller 211 and the second edge pressing roller 212 are both arranged on the upper pressing plate 23, and the third edge pressing roller 213 and the fourth edge pressing roller 214 are both arranged on the lower pressing plate 24; The main box body 22 is a U-shaped frame composed of a bottom plate 221 and two side plates. The two side plates are respectively the first side plate 222 and the second side plate 223 arranged in sequence along the moving direction of the strip as shown in Figure 6 ; there are entrances and exits for the strip passing through on each side plate. For example, the first side plate 222 is provided with a strip entrance, and the second side plate 223 is provided with a strip exit. The strip entrance and the strip exit are horizontally at the same height; The upper pressing plate 23 and the lower pressing plate 24 are both arranged between the two side plates, and the upper pressing plate 23 and the lower pressing plate 24 are both parallel to the bottom plate 221; The two telescopic link mechanisms are symmetrically distributed along the center line in the width direction of the strip, and each telescopic link mechanism is connected to the upper pressing plate 23 and the lower pressing plate 24 to drive the upper pressing plate 23 and the lower pressing plate 24 to extrude the rolled strip; Each telescopic link mechanism includes a plurality of telescopic link pairs 25, a guide plate 26, a ball screw seat 27, a ball screw 28, and a driving motor 29; the number of the plurality of telescopic link pairs is the same as the number of the plurality of edge pressing roller groups; The upper pressing plate 23 and the lower pressing plate 24 are both connected to each telescopic link pair 25, and each telescopic link pair 25 is also connected to the guide plate 26; specifically, each telescopic link pair 25 includes a first link 251 and a second link 252. The first end of the first link 251 is connected to the upper pressing plate 23, the second end of the first link 251 is connected to the guide plate 26, the first end of the second link 252 is connected to the lower pressing plate 24, the second end of the second link 252 is connected to the guide plate 26, and the first link 251 and the second link 252 are symmetrically distributed up and down in the thickness direction of the strip; The guide plate 26 is also connected to the first end of the ball screw seat 27. The second end of the ball screw seat 27 is connected to the first end of the ball screw 28. The second end of the ball screw 28 is connected to the drive motor 29. The drive motor 29 drives the guide plate 26 to move horizontally through the ball screw 28, thereby driving the upper and lower pressure plates to clamp the strip.

[0050] See Figure 10 and Figure 11 , each edge pressing roller includes: a flange seat 215, a rod shaft 216, a roller 217 and a set screw 218. The roller 217 is fixed to the upper pressure plate or the lower pressure plate through the flange seat 215. The flange seat 215 is sleeved outside the rod shaft 216. Threaded holes 219 are provided at the upper end of the flange seat 215 and the rod shaft 216. The rod shaft 216 is locked by assembling the set screw 218 into the threaded hole 219 to fix the angle of the edge pressing roller.

[0051] Optionally, see Figure 6 , the edge stress grading and regulating device 2 may further include a plurality of first heat preservation boxes provided on the upper pressure plate and a plurality of second heat preservation boxes 241 provided on the lower pressure plate. A first heat preservation box and a second heat preservation box 241 are provided between adjacent two edge pressing roller groups. The first heat preservation box and the second heat preservation box are uniformly heated by built-in electric heating wires to keep the strip warm, preventing the temperature of the strip from dropping rapidly after gradient annealing and affecting the regulation of the edge residual stress.

[0052] The post-processing equipment for the rolled strip provided by the embodiment of the present invention, the rolled strip sequentially passes through the gradient annealing device and the edge stress grading and regulating device. The gradient annealing device consists of an upper box body and a lower box body to form a closed cavity. The incoming strip is tensioned by a tension roller group and passes through a plurality of heating rollers arranged symmetrically up and down along the axis. The electric heating rollers perform annealing on the strip through the temperature gradient difference formed by the magnetic induction coils to compensate for the temperature drop at the edge of the strip, so as to initially cover the concentration of the edge residual stress of the rolled strip. A protective gas is injected into the cavity through a spray head to prevent the strip from being oxidized at high temperature. The surface temperature of the roller is monitored in real time through a temperature sensor. If it exceeds the set threshold, the controller in the gradient annealing device starts the cooling fan to reduce the surface temperature of the roller.

[0053] The edge stress grading and regulation module at least includes an insulation box, an upper pressure plate, and a lower pressure plate. A plurality of pairs of telescopic connecting rods are symmetrically arranged on both sides of the upper and lower pressure plates. A pressing belt is driven by a driving motor. Pressing roller wheels are symmetrically arranged laterally inside the upper and lower pressure plates. The angles of the pressing roller wheels are arranged in a grading manner from 15 degrees to 0 degrees. During the movement of the strip, a transverse compressive stress is applied to the edge, so that the residual stress is released step by step. During the stress regulation process, the annealing temperature is maintained by the insulation box to relieve the edge wave and warping phenomena caused by the residual tensile stress at the strip edge. The device of the present invention improves the defects such as edge wave and edge warping caused by residual stress concentration in the rolled strip in the continuous production process through the collaborative design of strip gradient annealing and edge stress grading regulation, and improves the surface quality and forming stability of the strip after rolling.

[0054] Although the present invention has been described in connection with various embodiments, it will be understood by those skilled in the art that other variations of the disclosed embodiments can be understood and achieved by viewing the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other components or steps, and the singular "a" or "an" does not exclude a plurality. A single processor or other unit may implement several functions recited in the claims. Certain measures are recited in mutually different dependent claims, but this does not mean that these measures cannot be combined to produce a good effect.

[0055] Although the present invention has been described in connection with specific features and their embodiments, it is obvious that various modifications and combinations can be made without departing from the spirit and scope of the present invention. Accordingly, the present specification and the drawings are merely an exemplary illustration of the present invention defined by the appended claims, and are considered to cover any and all modifications, variations, combinations, or equivalents within the scope of the present invention. Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention is also intended to include these changes and modifications.

Claims

1. A post-processing device for rolled strip, characterized in that, Comprising: A gradient annealing device and an edge stress grading and regulating device; the outlet end of the gradient annealing device is connected to the inlet end of the edge stress grading and regulating device; The gradient annealing device at least includes a plurality of heating roll groups; the plurality of heating roll groups are arranged at equal intervals along the moving direction of the strip; each heating roll group includes two heating rolls, and the two heating rolls respectively heat the upper surface and the lower surface of the rolled strip; each heating roll at least includes a magnetic induction coil, and the coil density of the magnetic induction coil decreases from the edge to the middle; The edge stress grading and regulating device at least includes a plurality of edge pressing roller groups arranged along the moving direction of the strip; each edge pressing roller group includes four edge pressing roller wheels; the angle between each edge pressing roller group and the width direction of the strip gradually decreases along the moving direction of the strip.

2. The post-processing equipment for the rolled strip according to claim 1, characterized in that, Each heating roll further includes a support roll core, an inner roll sleeve, an outer roll sleeve and two end caps; The support roll core is located at the center of the roll body of the heating roll; the material of the support roll core is a ceramic insulating material; The inner roll sleeve is sleeved outside the support roll core, the outer roll sleeve is sleeved outside the inner roll sleeve, and a heating roll cavity is formed between the inner roll sleeve and the outer roll sleeve; The magnetic induction coil is wound around the outer surface of the inner roll sleeve, and high-frequency alternating current is introduced into both ends of the magnetic induction coil; The two end caps are respectively fixed at both ends of the roll body of the heating roll.

3. The post-processing equipment for the rolled strip according to claim 1, characterized in that, The gradient annealing device further includes: a plurality of temperature acquisition devices; each temperature acquisition device is connected to one heating roll; the temperature acquisition device includes a sensor base and at least three temperature sensors fixed on the sensor base; the at least three temperature sensors are evenly distributed along the axial direction of the heating roll.

4. The post-processing equipment for the rolled strip according to claim 1, characterized in that, The gradient annealing device further includes an upper box body, a lower box body and a tension roll group; The upper box body and the lower box body are connected to form a closed cavity; The tension roll group is arranged at the entrance of the closed cavity.

5. The post-processing equipment for the rolled strip according to claim 4, characterized in that, The tension roll group includes a first tension roll, a second tension roll and a third tension roll; The first tension roll and the second tension roll are horizontally at the same height; the third tension roll is located below the first tension roll and the second tension roll.

6. The post-processing equipment for the rolled strip according to claim 1, characterized in that, The gradient annealing device further includes a heat dissipation device; the heat dissipation device is arranged above the plurality of heating rolls; The heat dissipation device includes a heat dissipation box body, a plurality of cooling motors and a plurality of fans; the heat dissipation box body is provided with grid-shaped heat dissipation holes; The plurality of cooling motors are arranged on the heat dissipation box body; The plurality of fans are all installed inside the heat dissipation box body; Each cooling motor is connected to one fan.

7. The post-processing equipment for the rolled strip according to claim 4, characterized in that, The gradient annealing device further includes a protective gas tank and at least one nozzle, the protective gas tank and at least one nozzle are both arranged on the upper box body, and at least one nozzle is connected to the protective gas tank.

8. The post-processing equipment for the rolled strip according to claim 1, characterized in that, The edge stress grading and regulating device further includes a main box body, an upper pressing plate, a lower pressing plate and two telescopic link mechanisms; The main box body is a U-shaped frame composed of a bottom plate and two side plates; The upper pressing plate and the lower pressing plate are both arranged between the two side plates, and each side plate is provided with an entrance and an exit for the strip to pass through; Each of the telescopic link mechanisms includes a plurality of telescopic link pairs, a guide plate, a ball screw seat, a ball screw, and a driving motor; The upper pressing plate and the lower pressing plate are both connected to each telescopic link pair, and each telescopic link pair is also connected to the guide plate; The guide plate is also connected to the first end of the ball screw seat, the second end of the ball screw seat is connected to the first end of the ball screw, and the second end of the ball screw is connected to the driving motor.

9. The post-processing equipment for the rolled strip according to claim 8, characterized in that, Each of the edge pressing rollers includes: a flange seat, a rod shaft, a roller, and a set screw; the roller is fixed to the upper pressing plate or the lower pressing plate through the flange seat; the flange seat is sleeved outside the rod shaft; threaded holes are provided at the upper end of the flange seat and the rod shaft, and the rod shaft is locked by assembling the set screw to fix the angle of the edge pressing roller.

10. The post-processing equipment for the rolled strip according to claim 9, characterized in that, The edge stress grading and regulating device further includes a plurality of first heat preservation boxes provided on the upper pressing plate and a plurality of second heat preservation boxes provided on the lower pressing plate; one first heat preservation box and one second heat preservation box are provided between adjacent two of the edge pressing roller groups.

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