A laser heating disc shear system and process for strip steel

Abstract

This invention relates to the field of metallurgical technology and discloses a laser-heated disc shear system and process method suitable for strip steel. The process method includes the following steps: Step 1, strip steel conveying and width detection; Step 2, laser heating; Step 3, disc shearing; Step 4, finished product coiling. This process method for laser-heated disc shears for strip steel uses laser to precisely and locally heat the edges of the strip steel. By heating the strip steel edges to 40-60℃, especially optimized to 60℃, the shearing strength of the strip steel in this area can be effectively reduced, thereby significantly reducing the shearing force. Calculations show that compared to room temperature shearing, the shearing force is reduced by approximately 23.3% when heated to 60℃. This allows the disc shear to more easily and smoothly complete the shearing of thin strip steel of about 0.2mm, fundamentally solving the edge quality defects such as burrs, shearing cracks, and flash that are easily generated by traditional cold shearing, and improving the smoothness and perpendicularity of the sheared section.

Description

Technical Field

[0001] This invention relates to the field of metallurgical technology, specifically to a laser-heated disc shearing system and process for strip steel, belonging to the field of green manufacturing of ultra-high grade oriented silicon steel. Background Technology

[0002] In strip steel processing in the metallurgical field, disc shearing is a common finishing process used to trim or slit strip steel. Traditional shearing processes mainly use cold shearing, which involves directly shearing the strip steel without heating. However, for thin strip steel (e.g., about 0.2mm), cold shearing has significant technical bottlenecks: the shearing force required is large, which can easily lead to quality defects such as burrs, shearing cracks, and flash on the strip steel edges. It also accelerates the wear of the shear blades, requiring frequent machine stops to replace the blades, which seriously affects production efficiency and product quality, and increases production costs. To reduce shearing force, the industry has also tried to use the method of preheating the entire strip for hot shearing. However, this method has high energy consumption and a large heating range, which can easily lead to uncontrollable changes in the properties of the strip (such as mechanical properties and metallographic structure). It also cannot achieve precise and local temperature control at the shearing position (i.e. the edge of the strip), making it difficult to maintain the stability of the strip matrix properties while ensuring the shearing quality. In addition, the width of the strip may fluctuate on a continuous production line. Existing heating and shearing devices usually cannot automatically follow and respond quickly to this fluctuation, resulting in deviation of the heating position or inconsistent shearing width, which affects the dimensional accuracy of the final product. Therefore, there is an urgent need for an innovative process and system that can achieve precise, efficient, and high-quality shearing of thin strip steel, especially strip steel with a thickness of about 0.2 mm. This process should be able to effectively reduce shearing resistance, solve edge quality defects, reduce shear blade wear, and adapt to changes in strip width to achieve automated and precise edge processing. Summary of the Invention

[0003] The purpose of this invention is to provide a laser-heated disc shearing system and process method for strip steel, in order to solve the problems mentioned in the background art, such as the easy generation of burrs, shearing cracks, large shearing force, and rapid wear of shear blades in traditional cold shearing of thin strip steel, as well as the high energy consumption, inaccurate heating, and inability to automatically adapt to changes in strip width of conventional hot shearing.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a process method for laser-heated disc shears for strip steel, the steps of which are as follows: Step 1, Strip Conveying and Width Detection: The strip to be sheared is smoothly conveyed to the laser heating area. The width of the strip is detected in real time by an automatic following device, and the laser heating position is adjusted according to the width change to ensure that the laser is accurately aligned with the edge of the strip. Step 2, Laser Heating: A laser is used to heat the edge of the strip steel. The heating width is 50-80mm, and the heating temperature is controlled at 40-60℃. A linear gradient mode is adopted so that the temperature gradually decreases from the edge of the strip steel to the inside at a gradient of 5-10℃ / mm, so as to achieve precise and gradual heating of the edge of the strip steel. Step 3, Disc shearing: The laser-heated strip immediately enters the disc shearing area, where the heated strip edges are sheared by the disc shear. The shearing speed is synchronized with the strip conveying speed, and the waste generated by shearing falls into the waste trough below. Step 4: Finished product winding: The sheared strip steel is wound up as the finished product.

[0005] Preferably, the laser is a 4000W fiber laser device, used to achieve precise temperature control of the strip edge; The heating temperature should be preferably controlled between 50-60℃, with the lowest shear force occurring when heated to 60℃. The highest heating temperature T(0) at the edge of the strip and the temperature T(x) at any position x within the heating area satisfy a functional relationship: , where T(0) takes values ​​ranging from 50 to 60℃; k is the temperature gradient coefficient, with a value range of 5-10℃ / mm; x is the distance measured from the edge of the strip, and its value ranges from 0 to 8 mm.

[0006] Preferably, the thickness of the strip is controlled between 0.18 and 0.22 mm; The automatic following device can adjust the laser heating position in real time according to the change in strip width, with a following error of no more than ±0.1mm, ensuring that the laser heating range is always located 1-2mm away from the edge of the strip.

[0007] Preferably, the process method reduces the shear force of the strip by laser heating, and the formula for calculating the shear force P is: ; Where K is the shear coefficient. For strip thickness, For cutting length, The shear strength of the strip at temperature T; strip shear strength With heating temperature The relationship within the 40-60℃ range is as follows: ; in room temperature The shear strength of the strip below This is the temperature coefficient of shear strength.

[0008] A laser-heated disc shearing system for strip steel, the system comprising: A laser is used to generate a high-energy laser beam to heat the edges of the strip during transport. An automatic following device, electrically connected to the laser, is used to automatically adjust the heating position and range of the laser according to the detected strip width, so that the laser beam always accurately acts on the edge of the strip. The automatic following device consists of a linear module and a slide table. A disc shear is installed on one side of the laser heating area of ​​the laser and is used to cut the edge of the strip steel after it has been heated by the laser. The disc shear is installed on a slide table on one side of two automatic following devices facing each other. A waste trough, located below the disc shear, is used to collect waste generated during shearing. Preferably, the system also includes a water chiller for cooling the laser head, with the cooling water temperature controlled at 20-25°C. The automatic following device is linked with the strip width detection sensor, responds to changes in strip width and adjusts the laser heating position to adapt to strips of different widths.

[0009] Preferably, the blade gap of the disc shear is adjusted to 0.02-0.03mm, and the rotation speed is adapted to the strip running speed of 1-3m / min; The system also includes a strip conveying and winding device, as well as a temperature sensor for real-time monitoring of the heating temperature of the strip edge.

[0010] Compared with the prior art, the beneficial effects of the present invention are: the process method applicable to laser-heated disc shears for strip steel is as follows: 1. Laser is used to precisely and locally heat the edge of the strip steel. By heating the edge of the strip steel to 40-60℃, especially when optimized to 60℃, the shear strength of the strip steel in this area can be effectively reduced, thereby significantly reducing the shear force. Calculations show that compared with room temperature shearing, the shear force is reduced by about 23.3% when heated to 60℃. This allows the disc shear to more easily and smoothly complete the shearing of thin strip steel of about 0.2mm, fundamentally solving the edge quality defects such as burrs, shear cracks, and flash that are easily generated by traditional cold shearing, and improving the smoothness and perpendicularity of the sheared section. 2. Unlike traditional overall preheating methods, this invention uses laser heating, which has concentrated energy and strong controllability. By controlling the heating width (50-80mm) and using a linearly gradual temperature field (decreasing from the edge to the inside at a gradient of 5-10℃ / mm), the heat energy can be precisely applied to a very small area of ​​the edge that needs to be sheared. This avoids problems such as decreased mechanical properties and changes in metallographic structure of the main body of the strip due to heating. While ensuring the shearing effect, it maintains the original properties of the strip substrate to the greatest extent. 3. Due to the significant reduction in shearing force, the impact and wear on the blades of the disc shear during operation are greatly reduced, thereby significantly extending the service life of the blades and reducing downtime and spare parts consumption caused by frequent blade replacement. This directly improves equipment utilization and reduces production and maintenance costs. 4. The integrated automatic following device can detect changes in strip width in real time and drive the laser heating head and the disc shear to adjust synchronously, ensuring that the heating and shearing positions always accurately track the edge of the strip (following error ≤ ±0.1mm). This feature perfectly solves the problem of shearing deviation and inconsistent width caused by fluctuations in the incoming material width, realizing fully automatic and high-precision continuous production, and ensuring the dimensional accuracy and consistency of the finished strip. 5. This invention derives and verifies the temperature gradient function ( The formula for calculating shear force establishes a clear mathematical model for the process effect and core parameters (such as heating temperature T and gradient coefficient k). This enables process control to move from empirical to scientific, facilitating precise parameter setting, process monitoring, and quality prediction, and providing a solid theoretical basis for process standardization and further optimization. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the overall three-dimensional structure of the present invention; Figure 2 This is a three-dimensional structural diagram of the overall working state of the present invention; Figure 3 This is a side view of the structure of the present invention; Figure 4 This is a front view schematic diagram of the laser structure of the present invention.

[0012] In the diagram: 1. Automatic following device; 2. Disc shear; 3. Laser; 4. Waste hopper. Detailed Implementation

[0013] 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.

[0014] Please see Figures 1-4 The present invention provides a technical solution: a process method for laser-heated disc shears for strip steel.

[0015] Example 1: Precision heating and shearing process of 0.2mm strip steel based on a 4000W laser: This embodiment specifically demonstrates how to use the system and process of the present invention to perform high-quality edge shearing on cold-rolled strip steel with a standard thickness of 0.2 mm. The system configuration is as follows: Figure 1 It mainly includes: an automatic following device 1, a disc shear 2, a 4000W fiber laser 3, a waste trough 4, and supporting water chillers and temperature sensors.

[0016] The specific process steps are as follows: Step 1: System Preparation and Parameter Preset Equipment debugging: Turn on the 4000W laser 3, preheat for 10-15 minutes, adjust the laser power to the rated 4000W, calibrate the laser emission angle, and ensure that the laser beam can be accurately focused on the edge of the strip, with a positioning deviation in the width direction not exceeding ±2mm.

[0017] Start the matching water chiller, check that the cooling circuit is unobstructed, and set and stabilize the cooling water temperature at 20-25℃ to ensure that the laser head temperature is controlled below 30℃ and to ensure its continuous and stable operation.

[0018] Debug the automatic following device 1, input the standard width parameters of the strip into the control system, and simulate the change of the strip width within ±50mm. After debugging, ensure that the response speed of the device can make the laser heating position follow the edge of the strip in real time, with a following error of no more than ±0.1mm.

[0019] Adjust the blade gap of the disc shear 2 to 0.02-0.03mm (0.025mm in this example) and set its speed to match the subsequent strip running speed of 1-3m / min (initially set to 2m / min in this example).

[0020] Step 2: Strip Conveying and Dynamic Following The strip steel with a thickness of 0.2mm (controlled within the range of 0.18-0.22mm) is smoothly conveyed to the laser heating area to ensure no deviation or shaking. The automatic following device 1 detects the actual width of the strip steel in real time at a frequency of once every 0.5 seconds. Once a change in width is detected, the device immediately drives the laser 3 and the disc shear 2 to move laterally as a whole, so that the laser focus and the shearing center line are always precisely aligned with the preset position 1-2mm (1.5mm in this example) from the edge of the strip steel.

[0021] Step 3: Precise Gradual Laser Heating Laser 3 heats the edge of the moving strip, with the heating range strictly controlled within a width of 50-80mm (in this example, the effective heating area is focused on approximately 60mm). The core process parameters are as follows: Temperature control: The highest heating temperature T(0) of the strip edge (at coordinate x=0) is controlled at 60℃ through real-time monitoring by temperature sensor.

[0022] Gradual heating mode: Linear gradual heating is adopted, from the edge of the strip (x=0) to the inside of the strip (x-increasing direction), the temperature gradually decreases with a set gradient. The temperature distribution in this embodiment follows a clear functional relationship: T(x) = T(0) - k × x; in: T(0) = 60℃; k (temperature gradient coefficient) = 8℃ / mm (value for 0.2mm thick strip steel); x: Distance from the edge of the strip (mm), 0≤x≤8mm (covering the main heating area); Example calculation: At x=1mm, the temperature T(1)=60-8×1=52℃, and at x=7.5mm, the temperature T(7.5)=60-8×7.5=0℃. This shows that within a width of about 7.5mm, the temperature gradually changes from 60℃ to close to room temperature, perfectly realizing the requirement that "the temperature rises in a stepwise manner from the edge of the strip to the disc shear head", and the temperature in the core shearing influence zone falls within the optimal range of 50-60℃.

[0023] Step 4: High-efficiency cutting with disc shears After being precisely heated by laser, the material at the edge of the strip is softened and immediately enters the second station of the disc shear for shearing. The shearing speed is strictly synchronized with the conveying speed of the strip at 2m / min.

[0024] Proof of shear force reduction: The effectiveness of this process is verified based on the provided mechanical calculation model.

[0025] Shear force formula: ; The shear coefficient K is set to 1.2 (suitable for disc shears and thin strip steel). The strip thickness is t=0.2mm.

[0026] Shear length (Suppose a two-sided shear scenario analysis).

[0027] τ(T): Shear strength of strip steel at temperature T (MPa).

[0028] Shear strength versus temperature (within the range of 40-60℃): ; τ (shear strength at room temperature 25℃) = 300 MPa; λ (temperature coefficient of shear strength) = 2 MPa / ℃; T (room temperature) = 25℃; Calculation comparison: Shearing at room temperature (25°C): ; Shear force P(25) = ; Heating to 40℃ and then cutting: ; Shear force P(40) = ; Heating to 60℃ and then shearing: ; Shear force P(60) = ; Conclusion: Calculations show that the shear force is 28.8 N at room temperature, 25.92 N at 40℃, and 22.08 N at 60℃. The shear force gradually decreases with increasing heating temperature, and the shear force at 60℃ is 23.3% lower than at room temperature and 14.8% lower than at 40℃. This demonstrates that the shear force is lowest and the shearing difficulty is lowest at 60℃, making it the easiest time to achieve shearing of the strip edges by the disc shear. This aligns with the mechanical law that increasing temperature leads to softening of metal materials and reduced shear strength. This system can solve the problems of shearing stability and strip width consistency after heating, which is significant not only for mechanical and production efficiency but also for fundamentally reducing carbon emissions.

[0029] Step 5: Finished product winding and post-processing The high-quality strip steel after shearing is then wound into finished steel coils by a subsequent coiling device, which can then proceed to subsequent processes according to the production plan.

[0030] Example 2: Demonstration of Adaptive Adjustment of Process Parameters This embodiment aims to illustrate how to adjust parameters according to subtle changes while keeping the core process framework unchanged, thereby demonstrating the robustness of the system.

[0031] Assume the strip running speed is adjusted from 2m / min to 1m / min.

[0032] Adjustment measures: Since the strip stays in the heating zone for a longer time, in order to prevent the edge temperature from exceeding the upper limit of 60°C under the same power, the laser power can be appropriately reduced from 4000W (for example, reduced to 3800W) through the control system to ensure that T(0) remains stable at 60°C and the core parameters such as temperature gradient coefficient k and heating width remain unchanged.

[0033] Results: After adjustment, the shearing quality remained consistent with that of Example 1, which proves that the process method has good speed adaptability through closed-loop temperature monitoring.

[0034] Quality control and results summary: During the production process, the heating temperature of the strip edge is checked every minute to ensure that it is within the range of 40-60℃ with a deviation of no more than ±3℃. The edges of the strip after shearing are sampled and inspected for each batch to confirm that there are no burrs or shear cracks and that the edge perpendicularity deviation is less than ±0.1mm.

[0035] The most direct effect of using this invention is: Quality improvement: Solved the problems of burrs and cracks during shearing of 0.2mm thin strip steel.

[0036] Efficiency and cost optimization: The shearing force was reduced by nearly 1 / 4, which significantly reduced shear blade wear, extended the blade change cycle, and improved equipment operating rate.

[0037] Automation and Precision: The automatic following device ensures that the entire process adapts to the fluctuations in strip width, achieving precise edge processing at the ±0.1mm level.

[0038] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A process suitable for laser heating of a strip steel for a disc shear, characterized in that: The process steps are as follows: Step 1, strip steel conveying and width detection: The strip steel to be sheared with a thickness controlled between 0.18-0.22mm is smoothly conveyed to the laser heating area. The width of the strip steel is detected in real time by an automatic following device (1), and the laser heating position is adjusted according to the width change. The following error does not exceed ±0.1mm, ensuring that the laser heating range is always located 1-2mm away from the edge of the strip steel. Step 2, laser heating: The edge of the strip is heated by a laser (3) with a heating width of 50-80mm and a heating temperature of 40-60℃. A linear gradient mode is adopted so that the temperature gradually decreases from the edge of the strip to the inside at a gradient of 5-10℃ / mm, so as to achieve precise gradient heating of the edge of the strip. The highest heating temperature T(0) at the edge of the strip and the temperature T(x) at any position x in the heating area satisfy the functional relationship: T(x) = T(0) - k×x, where T(0) takes values ​​in the range of 50-60℃; k is the temperature gradient coefficient, with a value range of 5-10℃ / mm; x is the distance measured from the edge of the strip, and its value ranges from 0 to x and from 8 mm. Step 3, disc shear (2) shearing: The strip steel heated by laser immediately enters the disc shear (2) area, and the disc shear (2) shears the edge of the heated strip steel. The shearing speed is synchronized with the strip steel conveying speed, and the waste generated by shearing falls into the waste trough (4) below. Step 4: Finished product winding: The sheared strip steel is wound up as the finished product; The process method reduces the shear force of the strip steel by laser heating, and the formula for calculating the shear force is: P = K × t × L × τ (T); Where P is the shear force, K is the shear coefficient, t is the strip thickness, L is the shear length, and τ(T) is the shear strength of the strip at temperature T. The relationship between the shear strength τ(T) of the strip steel and the heating temperature T in the range of 40-60℃ is: τ(T) = τ0 - λ × (T - T2); Where τ0 is the shear strength of the strip at room temperature T2, and λ is the temperature coefficient of shear strength.

2. A process for laser heating of a strip steel for a disc shear as claimed in claim 1, wherein: The laser (3) is a 4000W fiber laser device used to achieve precise temperature control of the strip edge; The heating temperature should be preferably controlled between 50-60℃, with the shear force being lowest when heated to 60℃.

3. A laser heating disc shear system for strip steel suitable for carrying out the process method according to any one of claims 1-2, characterized in that: The system includes: Laser (3) is used to generate a high-energy laser beam to heat the edge of the strip during transport; An automatic following device (1) is electrically connected to the laser (3) and is used to automatically adjust the heating position and range of the laser (3) according to the detected strip width, so that the laser beam always accurately acts at a position 1-2mm away from the edge of the strip, and the following error does not exceed ±0.1mm. The automatic following device (1) consists of a linear module and a slide table. The disc shear (2) is set on one side of the laser heating area of ​​the laser (3) and is used to cut the edge of the strip steel after laser heating. The disc shear (2) is installed on the slide table on the opposite side of the two automatic following devices (1). Waste trough (4) is located below the disc shear (2) and is used to receive waste generated during shearing.

4. A laser heating disc shear system for strip steel as defined in claim 3 wherein: The system also includes a water chiller that is compatible with the laser (3) for cooling the laser head of the laser (3), and the cooling water temperature is controlled at 20-25℃. The automatic following device (1) is linked with the strip width detection sensor, responds to changes in strip width and adjusts the laser heating position to adapt to strips of different widths.

5. A laser heating disc shear system for strip steel as defined in claim 3 wherein: The blade gap of the disc shear (2) is adjusted to 0.02-0.03mm, and the rotation speed is adapted to the strip running speed of 1-3m / min; The system also includes a strip conveying and winding device, as well as a temperature sensor for real-time monitoring of the heating temperature of the strip edge.

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