Technological process configuration method and system for roughing mill unit of hot continuous rolling production line

Abstract

The invention provides a technological process configuration method and system for a roughing mill unit of a hot continuous rolling production line, and relates to the technical field of hot continuous rolling, the technological process configuration method and system are applied to the roughing mill unit, the roughing mill unit comprises a horizontal rolling mill and a vertical rolling mill, and the technological process configuration method comprises the steps that the total broadsiding amount and target broadsiding data of a slab to be rolled are obtained, the method comprises the following steps: acquiring a total broadsiding amount of a vertical rolling mill, comparing the total broadsiding amount with target broadsiding data, when the total broadsiding amount is greater than the target broadsiding data, obtaining a total width reduction amount of the vertical rolling mill according to the total broadsiding amount, and executing a process parameter configuration process of the vertical rolling mill to obtain a temporary rolling reduction of each rolling pass of the vertical rolling mill. By means of the process, the rolling reduction of the vertical rolling mill can be accurately calculated and distributed, the width change of the plate blank can be more accurately controlled, the size precision of a final product is ensured, and therefore the rejection rate caused by the unqualified size is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of hot rolling, and in particular to a process flow configuration method and system for a roughing mill group of a hot rolling production line. Background Art

[0002] In the process flow of the roughing mill of a hot rolling production line, the relevant technology mainly obtains the total width expansion and target width expansion data of the slab to be rolled first, and then compares them. If the total width expansion exceeds the target width expansion data, the total width reduction of the vertical roller mill is roughly estimated. However, the subsequent process parameter configuration process is relatively rough, and the reduction amount of each rolling pass of the vertical roller mill is usually set simply based on experience or a fixed pattern, lacking a precise adjustment and optimization mechanism.

[0003] This traditional process has many shortcomings: on the one hand, it is impossible to flexibly adjust the reduction amount of each pass of the vertical roller mill according to the specific working conditions, resulting in unsatisfactory width reduction effect and difficulty in meeting high-precision width control requirements; on the other hand, due to unreasonable distribution of reduction amount, it is easy for the reduction amount of local passes to be too large or too small, which not only affects the rolling quality, but also may increase the risk of equipment failure, reduce production efficiency, and make it difficult for the entire rolling process to reach the optimal state. Summary of the Invention

[0004] The problem solved by the present invention is one or more of the above-mentioned related technical problems.

[0005] In order to solve the above problems, the present invention provides a process flow configuration method and system for a roughing mill group of a hot rolling production line.

[0006] In a first aspect, the present invention provides a process flow configuration method for a roughing mill group of a hot rolling production line, which is applied to the roughing mill group, wherein the roughing mill group includes an edger mill, and the process flow configuration method for the roughing mill group of the hot rolling production line includes: Obtaining the total width expansion and target width expansion data of the slab to be rolled, and comparing the total width expansion with the target width expansion data, When the total width expansion is greater than the target width expansion data, the total width reduction of the vertical rolling mill is obtained according to the total width expansion, and the process parameter configuration process of the vertical rolling mill is executed to obtain the temporary reduction of each rolling pass of the vertical rolling mill; The process parameter configuration process of the vertical roller mill includes: The initial reduction of each rolling pass of the vertical rolling mill is obtained according to the total width reduction and each preset pass distribution ratio. The comparison result is obtained by comparing the initial reduction of each rolling pass of the vertical roller mill with a preset threshold value. Adjusting the initial reduction of each rolling pass of the vertical rolling mill according to the comparison result to obtain a temporary reduction of each rolling pass of the vertical rolling mill; The final reduction amount of each rolling pass of the vertical rolling mill is determined according to each of the temporary reduction amounts.

[0007] Optionally, adjusting the initial reduction of each rolling pass of the vertical roller mill according to the comparison result to obtain the temporary reduction of each rolling pass of the vertical roller mill includes: When the initial reduction of each rolling pass of the vertical rolling mill is greater than the preset threshold, Using the preset threshold as the first reduction of each rolling pass of the vertical rolling mill, and executing a countermeasure process; The countermeasure process includes: Determine the rolling force, rolling torque and motor power corresponding to the rolling pass according to each of the first reductions; The rolling force, the rolling torque and the motor power are judged respectively according to corresponding preset limit values to obtain a judgment result, and a temporary reduction amount of the vertical roller mill corresponding to the rolling pass is determined according to the judgment result.

[0008] Optionally, determining the temporary reduction of the vertical rolling mill corresponding to the rolling pass according to the judgment result includes: If at least one of the rolling force, the rolling torque and the motor power exceeds the corresponding preset limit, a calculation is performed based on the corresponding preset limit to obtain a temporary reduction of the edger mill corresponding to the rolling pass; When the rolling force, the rolling torque and the motor power are all less than or equal to the corresponding preset limit values, the preset threshold value is used as the temporary reduction amount of the vertical rolling mill corresponding to the rolling pass.

[0009] Optionally, adjusting the initial reduction of each rolling pass of the vertical rolling mill according to the comparison result to obtain the temporary reduction of each rolling pass of the vertical rolling mill further comprises: When the initial reduction of each target rolling pass is greater than the preset threshold, and the initial reduction of the non-target rolling pass is less than or equal to the preset threshold, the preset threshold is used as the first reduction of each target rolling pass, and the countermeasure process is performed to obtain a temporary reduction of each target rolling pass; Determining difference data based on the temporary reductions of all the target rolling passes and the initial reductions of the corresponding target rolling passes; Dividing the difference data according to the corresponding pass allocation rate, and updating the initial reduction of the corresponding non-target rolling pass according to the divided data to obtain the target reduction of the non-target rolling pass; When the target reduction of the non-target rolling pass is less than or equal to the preset threshold, the target reduction is used as the first reduction of the non-target rolling pass, and the countermeasure process is performed to obtain a temporary reduction of the non-target rolling pass; Determining a width expansion amount corresponding to the rolling pass according to the temporary reduction amount of the non-target rolling pass; updating the total width reduction according to all the width expansion amounts, and repeating the steps after comparing the updated total width reduction with the target width expansion data until a stop condition is met, thereby obtaining a temporary reduction for the non-target rolling pass; The target rolling pass is any of the rolling passes; the width expansion amount is the width expansion of the rolling pass after the dog bone is generated by the vertical roller mill and then the horizontal rolling mill is used to press it down.

[0010] Optionally, obtaining the total width expansion and target width expansion data of the slab to be rolled includes: Acquire the size data of the slab to be rolled and the parameter configuration data of the horizontal rolling mill, wherein the size data includes the initial size data and the width of the intermediate slab; Determining the total width expansion of the slab to be rolled according to the initial size data and the parameter configuration data; Target width data is obtained according to the intermediate billet width and the initial size data.

[0011] Optionally, updating the total width reduction amount according to all the width expansion amounts includes: Determining the outlet width of the final rolling pass according to all the width expansion amounts, and obtaining a target width expansion amount according to the outlet width of the final rolling pass and the intermediate billet width; The current total width reduction amount is updated according to the target width expansion amount.

[0012] Optionally, the stop condition includes that the target width expansion satisfies a width control index and a preset number of cycles.

[0013] Optionally, the process of obtaining the preset threshold includes: Determining the maximum reduction corresponding to each rolling pass according to the current thickness of the slab to be rolled in each rolling pass of the vertical rolling mill; Obtaining the maximum reduction of the vertical rolling mill; The corresponding preset threshold is determined according to the maximum reduction of each rolling pass and the maximum reduction of the vertical rolling mill.

[0014] In a second aspect, the present invention provides a process flow configuration system for a roughing mill group of a hot rolling production line, comprising a memory and a processor; the memory is used to store a computer program; the processor is used to implement the process flow configuration method for the roughing mill group of a hot rolling production line as described in the first aspect when executing the computer program. In a third aspect, the present invention provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the process flow configuration method of the roughing mill group of the hot rolling production line as described in the first aspect is implemented.

[0015] The beneficial effects of the process flow configuration method and system of the roughing mill group of a hot rolling production line of the present invention are: First, the total width expansion and target width expansion data for the slab to be rolled are obtained. The total width expansion is the total change in the slab's width during the rolling process, calculated or measured, after rolling in the horizontal mill alone, with the vertical mill inactive. It reflects the cumulative increase in slab width over all rolling passes. The target width expansion is the target width that the slab should achieve after rolling, as specified in the process requirements. This is determined based on the final product's dimensional requirements and process design. If the total width expansion exceeds the target width expansion, the horizontal mill alone cannot meet the process requirements, and additional width reduction operations in the vertical mill are required.

[0016] Then calculate the total width reduction of the vertical roller mill, which is obtained by subtracting the target width expansion data from the total width expansion. It represents the total width reduction required by the vertical roller mill in all rolling passes.

[0017] Finally, the vertical mill process parameter configuration process is executed: the initial reduction for each rolling pass of the vertical mill is calculated based on the total width reduction and the preset pass allocation ratio. The pass allocation ratio is pre-set according to the process design and is used to rationally distribute the total width reduction to each pass. The initial reduction of each pass is compared with preset thresholds (such as equipment capacity limitations and process safety limits) to determine whether it exceeds the allowable range. If the initial reduction of a particular pass exceeds the preset threshold, the reduction of that pass is adjusted to within the threshold. This adjusted reduction is called the temporary reduction.

[0018] Based on the adjusted temporary reduction, the reduction for each pass is finally determined to ensure that the entire rolling process meets the process requirements and equipment capabilities.

[0019] Therefore, the present invention accurately calculates and distributes the reduction of the vertical roller mill through the above process, enabling more precise control of slab width variation, ensuring the dimensional accuracy of the final product and reducing scrap rates due to dimensional non-conformity. Furthermore, the reduction calculation takes into account the equipment's preset threshold, preventing overload. This not only extends the equipment's service life but also improves its operating efficiency and reduces downtime caused by equipment failures.

[0020] This method allows for flexible adjustment of the reduction distribution based on different slab characteristics and process requirements, and can adapt to a variety of production scenarios. For example, for slabs of different materials, thicknesses, and widths, the specific process requirements can be met by adjusting the pass distribution rate and reduction. After the reduction is properly distributed, the adjustment time and rework times during the rolling process caused by unreasonable reduction are reduced, which helps to shorten the production cycle and improve overall production efficiency. At the same time, due to the improved product quality, increased production efficiency, and reduced equipment failure and scrap rates, this method can effectively reduce production costs, which is of great significance to improving the economic benefits of the enterprise.

[0021] In summary, this process configuration method, through scientific and rational calculation and adjustment, ensures that the vertical mill's reduction distribution during roughing meets both process requirements and equipment capabilities. This method not only improves rolling accuracy and production efficiency, but also optimizes equipment utilization and reduces production costs, resulting in significant economic benefits and process optimization. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is one of the flow diagrams of a method for configuring a process flow of a roughing mill group in a hot rolling production line according to an embodiment of the present invention; Figure 2 This is a second flow chart of a method for configuring a process flow of a roughing mill group in a hot rolling production line according to an embodiment of the present invention; Figure 3 This is a schematic diagram of a layout of a roughing mill group according to an embodiment of the present invention; Figure 4 This is a second schematic diagram of an arrangement of a roughing mill group according to an embodiment of the present invention; Figure 5 This is a third schematic diagram of an arrangement of a roughing mill group according to an embodiment of the present invention; Figure 6 This is a third flow chart of a method for configuring a process flow of a roughing mill group of a hot rolling production line according to an embodiment of the present invention; Figure 7 For the embodiment of the present invention Figure 3 The calculation results of the layout type of the roughing mill are set according to the specification of reducing the width of the neutral roller mill by 100mm. DETAILED DESCRIPTION

[0023] To make the above-mentioned objects, features, and advantages of the present invention more clearly understood, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings. Although certain embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be construed as being limited to the embodiments described herein. Instead, these embodiments are provided to provide a more thorough and complete understanding of the present invention. It should be understood that the drawings and embodiments of the present invention are for illustrative purposes only and are not intended to limit the scope of protection of the present invention.

[0024] It should be understood that the various steps described in the method embodiments of the present invention may be performed in different orders and / or in parallel. In addition, the method embodiments may include additional steps and / or omit the steps shown. The scope of the present invention is not limited in this respect.

[0025] The term "including" and its variations used in this document are open inclusions, that is, "including but not limited to"; the term "based on" means "based at least in part on"; the term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one other embodiment"; the term "some embodiments" means "at least some embodiments"; the term "optionally" means "optional embodiments". The relevant definitions of other terms will be given in the following description. It should be noted that the concepts of "first", "second", etc. mentioned in the present invention are only used to distinguish different devices, modules or units, and are not used to limit the order or interdependence of the functions performed by these devices, modules or units.

[0026] It should be noted that the modifications of "one" and "multiple" mentioned in the present invention are illustrative rather than restrictive. Those skilled in the art should understand that unless otherwise clearly indicated in the context, it should be understood as "one or more".

[0027] The names of the messages or information exchanged between multiple devices in the embodiments of the present invention are only used for illustrative purposes and are not used to limit the scope of these messages or information.

[0028] In the roughing area of a hot rolling line, existing processes typically deploy an attached vertical roller mill in front of each roughing mill, with the vertical roller mill performing only the odd-numbered passes within the unit. This traditional configuration results in limited width reduction capability, typically exceeding 50mm. When a larger width reduction is required, the line must rely on an additional width-fixing press, increasing equipment investment and production costs. Furthermore, the production process is complex and lacks flexibility, making it difficult to adapt to changing production needs.

[0029] In response to the problems existing in the above-mentioned related technologies, an embodiment of the present invention provides a process flow configuration method and system for a roughing mill group of a hot rolling production line.

[0030] like Figure 1 and Figure 2 As shown, an embodiment of the present invention provides a process flow configuration method for a roughing mill group of a hot rolling production line, which is applied to the roughing mill group. The roughing mill group includes a vertical rolling mill. The process flow configuration method for the roughing mill group of the hot rolling production line includes: Step S100 : obtaining total width expansion and target width expansion data of a slab to be rolled, and comparing the total width expansion with the target width expansion data.

[0031] Specifically, the layout before and after the roughing area of a hot rolling line typically includes a heating furnace, a high-pressure water descaling machine, a roughing mill, a heat shield, and a shearing machine. The roughing mill typically consists of one or two roughing mills, each with an attached vertical roller mill. The vertical roller mill is primarily used to eliminate the widening of the slab before roughing and after it is rolled into the intermediate bar in the roughing mill.

[0032] When the width of the intermediate billet of the hot rolling production line is smaller than the width of the slab, a width reduction rolling process is required. Since a vertical roller mill is configured in front of the roughing mill, the rolling passes of the vertical roller mill are odd-numbered passes of this unit. Due to the restrictions on the reduction amount and the number of passes, the width reduction of the slab is limited, usually less than 50mm. Therefore, when the rolling line requires a larger width reduction, a fixed-width press is required.

[0033] Therefore, in this embodiment, an attached vertical roller mill is arranged before and after each roughing mill in the roughing area of the hot rolling production line. Each rolling process from the slab (to be rolled slab) to the intermediate bar passes through the vertical roller mill and the roughing mill in succession, which can not only eliminate the width expansion in the roughing stage, but also achieve width reduction of more than 100mm. Figure 3-5 The following are schematic diagrams of the layout of the roughing mill group.

[0034] Figure 3 The diagram shows a roughing mill layout consisting of a roughing mill R1. Vertical roll mills E1 and E2 are located before and after roughing mill R1, respectively, in an attached layout. This design enables roughing mill R1 to perform rolling in three, five, seven, or nine passes. In each pass, depending on the rolling direction, the workpiece passes through vertical roll mill E1 or E2 for initial width control before entering roughing mill R1 for thickness rolling.

[0035] Figure 4Another roughing mill layout is presented, consisting of two roughing mills, R1 and R2. Roughing mill R1 is preceded by vertical roll mill E1, while vertical roll mills E2 and E3 are located in front and behind roughing mill R2, respectively. The vertical roll mills and roughing mills are also attached to each other. In this layout, roughing mill R1 is primarily responsible for rolling passes 1 and 3, while roughing mill R2 handles passes 3, 5, and 7. When roughing mill R1 is rolling, regardless of whether the pass is odd or even, the product must first pass through the corresponding vertical roll mill (E1 or E2) according to the rolling direction before entering roughing mill R1. Similarly, when roughing mill R2 is rolling, the product must first pass through the corresponding vertical roll mill (E3 or E4) according to the rolling direction before entering roughing mill R2.

[0036] Figure 5 The roughing mill arrangement described is similar to Figure 4 The roughing mill is similar to the conventional mill, consisting of two roughing mills, R1 and R2. Roughing mill R1 is preceded by vertical roll mill E1, while vertical roll mills E2 and E3 are placed before and after roughing mill R2. The vertical roll mills and roughing mills are attached to each other. The difference is that roughing mill R1 processes the 1st and 3rd passes. During the rolling process, for odd-numbered passes, the product first passes through vertical roll mill E1 before entering roughing mill R1; for even-numbered passes, the product passes directly through roughing mill R1. Roughing mill R2 is responsible for rolling passes 3, 5, and 7. Regardless of the pass, the product must first pass through the corresponding vertical roll mill (E2 or E3) according to the rolling direction before entering roughing mill R2 for rolling.

[0037] It should be noted that the total number of rolling passes of the roughing mill is set according to specific actual conditions.

[0038] Step S100 is the key starting point for configuring the roughing mill process flow for the entire hot rolling line. First, the total width expansion of the slab to be rolled is determined using specialized simulation software or statistical models based on extensive historical production data. This total width expansion is the expected total change in the slab's width after rolling in the horizontal mill, without the vertical mill involved. It reflects the cumulative increase in slab width over all rolling passes in the horizontal mill. Simultaneously, target width expansion data is obtained from the production plan or product specifications. This target is determined based on the dimensional accuracy requirements of the final product and the width constraints of subsequent production processes.

[0039] Accurately comparing the total spread to the target spread requires numerical calculations, such as simple subtraction to determine the difference, or more complex deviation analysis algorithms to assess the degree of excess. Manual comparisons can be performed using specialized comparison tools or tables to visually display the differences.

[0040] By comparing the total width expansion with the target width expansion data, it is possible to accurately determine whether the slab's width changes during rolling meet expectations. If the total width expansion exceeds the target, timely adjustments can be made to avoid product quality issues such as dimensional tolerances and poor shape caused by excessive width, thereby improving product qualification rates and quality stability.

[0041] The comparison results provide a clear direction and basis for subsequent process parameter adjustments. When adjusting process parameters for width reduction in the vertical mill, the comparison results can be used to rationally determine the total width reduction for the vertical mill, allowing for a more scientific allocation of reductions for each pass. This optimizes the entire rolling process, making each pass more coordinated and efficient, while reducing unnecessary process steps and wasted resources.

[0042] Step S200: When the total width expansion is greater than the target width expansion data, the total width reduction of the vertical rolling mill is obtained according to the total width expansion, and the process parameter configuration process of the vertical rolling mill is executed to obtain the temporary reduction of each rolling pass of the vertical rolling mill.

[0043] The process parameter configuration process of the vertical roller mill includes: The initial reduction of each rolling pass of the vertical rolling mill is obtained according to the total width reduction and each preset pass distribution ratio. The comparison result is obtained by comparing the initial reduction of each rolling pass of the vertical roller mill with the preset threshold value. The initial reduction of each rolling pass of the vertical rolling mill is adjusted according to the comparison result to obtain a temporary reduction of each rolling pass of the vertical rolling mill.

[0044] Specifically, when the total width expansion exceeds the target width, indicating that the target width cannot be achieved with the horizontal mill alone, the vertical mill process parameter configuration process must be initiated. Based on the excess width, the vertical mill's total width reduction is calculated, providing a basis for allocating reductions in subsequent rolling passes.

[0045] The initial reduction for each rolling pass in the vertical mill is calculated based on the total width reduction and the preset distribution ratio for each pass. The pass distribution ratio is determined by comprehensively considering factors such as rolling process requirements, equipment performance, and material properties of the rolled product to ensure that the total width reduction is reasonably distributed among the passes, laying the foundation for the rolling process.

[0046] The initial reduction of each pass is compared with a preset threshold. This threshold is set based on equipment capacity limitations, process safety requirements, and rolling quality standards to prevent equipment overload, ensure a safe and stable rolling process, and guarantee the dimensional accuracy and surface quality of the rolled product.

[0047] Based on the comparison results, the reductions for passes exceeding the threshold are adjusted. Following specific rules and algorithms, the reductions are redistributed to ensure that each pass meets process and equipment requirements. This adjusted reduction serves as a provisional reduction, providing a reference for determining the final reduction.

[0048] By scientifically configuring process parameters and rationally allocating reductions for each pass, precise control of the rolling process is achieved. This ensures that each pass of the vertical roller mill meets process requirements, improves rolling accuracy and product quality, reduces dimensional deviations and surface defects, and enhances the company's market competitiveness.

[0049] Taking into account factors such as the total width reduction, pass distribution rate and equipment capacity limitations, the distribution of reduction in each pass is optimized to ensure that all stages of the rolling process are closely connected, coordinated and unified, ensuring that the rolling process is efficient and stable and improving production efficiency.

[0050] Taking full account of equipment performance and safety limitations, the pressure reduction is adjusted according to preset thresholds to avoid equipment overload. This reduces equipment failure rates, extends service life, reduces maintenance costs and downtime, and improves production efficiency and enterprise economic benefits.

[0051] This process flow can be flexibly adjusted to suit the characteristics and process requirements of different slabs. Whether slabs of varying materials and thicknesses, or products with varying widths, by optimizing the pass distribution ratio and reduction, products that meet the requirements can be efficiently and stably produced, improving the company's market adaptability and competitiveness.

[0052] Step S300: determining the final reduction of each rolling pass of the vertical rolling mill according to each temporary reduction.

[0053] Specifically, the final reduction for each rolling pass of the vertical mill is determined by comprehensively considering factors such as temporary reduction, process requirements, equipment performance, and rolling process stability. Following rolling process principles, the appropriate reduction for each pass is ensured, forming a complete rolling process parameter system to guide the stable and efficient operation of the vertical mill.

[0054] In this embodiment, the process flow configuration method of the rough rolling mill group of the hot rolling production line first obtains the total width expansion and target width expansion data of the slab to be rolled. The total width expansion is the total change in the width direction of the slab during the rolling process obtained by calculation or measurement after the vertical roller mill is not working and only rolled by the horizontal rolling mill. It reflects the cumulative increase in the width of the slab in all rolling passes. Target width expansion data: This is the target width value that the slab should reach after rolling, as set in the process requirements. It is determined based on the size requirements of the final product and the process design. If the total width expansion is greater than the target width expansion data, it means that the width expansion of the horizontal rolling mill alone cannot meet the process requirements, and the vertical roller mill is required to perform additional width reduction operations.

[0055] Then calculate the total width reduction of the vertical roller mill, which is obtained by subtracting the target width expansion data from the total width expansion. It represents the total width reduction required by the vertical roller mill in all rolling passes.

[0056] Finally, the vertical mill process parameter configuration process is executed: the initial reduction for each rolling pass of the vertical mill is calculated based on the total width reduction and the preset pass allocation ratio. The pass allocation ratio is pre-set according to the process design and is used to rationally distribute the total width reduction to each pass. The initial reduction of each pass is compared with preset thresholds (such as equipment capacity limitations and process safety limits) to determine whether it exceeds the allowable range. If the initial reduction of a particular pass exceeds the preset threshold, the reduction of that pass is adjusted to within the threshold. This adjusted reduction is called the temporary reduction.

[0057] Based on the adjusted temporary reduction, the reduction for each pass is finally determined to ensure that the entire rolling process meets the process requirements and equipment capabilities.

[0058] Therefore, the present invention accurately calculates and distributes the reduction of the vertical roller mill through the above process, enabling more precise control of slab width variation, ensuring the dimensional accuracy of the final product and reducing scrap rates due to dimensional non-conformity. Furthermore, the reduction calculation takes into account the equipment's preset threshold, preventing overload. This not only extends the equipment's service life but also improves its operating efficiency and reduces downtime caused by equipment failures.

[0059] This method allows for flexible adjustment of the reduction distribution based on different slab characteristics and process requirements, and can adapt to a variety of production scenarios. For example, for slabs of different materials, thicknesses, and widths, the specific process requirements can be met by adjusting the pass distribution rate and reduction. After the reduction is properly distributed, the adjustment time and rework times during the rolling process caused by unreasonable reduction are reduced, which helps to shorten the production cycle and improve overall production efficiency. At the same time, due to the improved product quality, increased production efficiency, and reduced equipment failure and scrap rates, this method can effectively reduce production costs, which is of great significance to improving the economic benefits of the enterprise.

[0060] In summary, this process configuration method, through scientific and rational calculation and adjustment, ensures that the vertical mill's reduction distribution during roughing meets both process requirements and equipment capabilities. This method not only improves rolling accuracy and production efficiency, but also optimizes equipment utilization and reduces production costs, resulting in significant economic benefits and process optimization.

[0061] Optionally, adjusting the initial reduction of each rolling pass of the vertical roller mill according to the comparison result to obtain the temporary reduction of each rolling pass of the vertical roller mill includes: When the initial reduction of each rolling pass of the vertical rolling mill is greater than the preset threshold, Using the preset threshold as the first reduction of each rolling pass of the vertical rolling mill, and executing a countermeasure process; The countermeasure process includes: Determine the rolling force, rolling torque and motor power corresponding to the rolling pass according to each of the first reductions; The rolling force, the rolling torque and the motor power are judged respectively according to corresponding preset limit values to obtain a judgment result, and a temporary reduction amount of the vertical roller mill corresponding to the rolling pass is determined according to the judgment result.

[0062] Optionally, determining the temporary reduction of the vertical rolling mill corresponding to the rolling pass according to the judgment result includes: If at least one of the rolling force, the rolling torque and the motor power exceeds the corresponding preset limit, a calculation is performed based on the corresponding preset limit to obtain a temporary reduction of the edger mill corresponding to the rolling pass; When the rolling force, the rolling torque and the motor power are all less than or equal to the corresponding preset limit values, the preset threshold value is used as the temporary reduction amount of the vertical rolling mill corresponding to the rolling pass.

[0063] Specifically, when the initial reduction of each rolling pass of the vertical roller mill is greater than a preset threshold, the preset threshold is used as the first reduction of each rolling pass, and a countermeasure process is performed. The countermeasure process includes the following steps: Based on the first reduction of each pass, the corresponding rolling force, rolling torque, and motor power are calculated. These parameters are calculated based on the mechanical properties of the material, the geometric parameters of the rolls, and the rolling process conditions. For example, the rolling force can be calculated based on the yield strength of the material (the material of the slab to be rolled) and the reduction; the rolling torque can be calculated based on the rolling force and the roll radius; and the motor power can be calculated based on the rolling force and the rolling speed.

[0064] The calculated rolling force, rolling torque and motor power are compared with the corresponding preset limit values.

[0065] If any of the rolling force, rolling torque or motor power exceeds the preset limit, adjustments are made according to the corresponding preset limit, and the reduction amount for that pass is recalculated to obtain a temporary reduction amount.

[0066] If all parameters are less than or equal to the preset limit, the preset threshold is used as the temporary reduction for that pass.

[0067] In the above process, if the initial reduction for all passes exceeds a preset threshold, the threshold is used as the first reduction, ensuring the rationality and feasibility of the reduction. Through a countermeasure process, the reduction is further adjusted based on the rolling force, rolling torque, and motor power, ensuring that the rolling process remains within the equipment's permitted range. This precise control helps improve rolling accuracy and stability, reducing the risk of excessive rolling force or motor power caused by excessive reduction.

[0068] By using a preset threshold as the first reduction and adjusting the pressure according to the equipment's preset limits, the equipment is prevented from operating under overload conditions. This helps reduce equipment wear and failure risks, extending equipment life and reducing maintenance costs and downtime. Safe equipment operation is crucial for production efficiency and product quality.

[0069] The judgment and adjustment mechanism during the countermeasure process enables each pass's reduction to be optimized based on the actual rolling force, rolling torque, and motor power. This optimization not only improves the efficiency of the rolling process, but also ensures rolling quality and reduces production delays and resource waste caused by unreasonable parameters.

[0070] By properly adjusting the reduction, unnecessary downtime and adjustment time are avoided, making the rolling process smoother and more efficient. This reduces the number of rework and adjustments caused by improper parameter settings, shortens the production cycle, and improves overall production efficiency.

[0071] Precisely controlling the reduction and rolling parameters helps ensure the dimensional accuracy and surface quality of the rolled product. This reduces dimensional deviations and surface defects caused by excessive or insufficient rolling forces, improves product qualification and consistency, and ultimately enhances product quality.

[0072] Optionally, adjusting the initial reduction of each rolling pass of the vertical rolling mill according to the comparison result to obtain the temporary reduction of each rolling pass of the vertical rolling mill further comprises: When the initial reduction of each target rolling pass is greater than the preset threshold, and the initial reduction of the non-target rolling pass is less than or equal to the preset threshold, the preset threshold is used as the first reduction of each target rolling pass, and the countermeasure process is performed to obtain a temporary reduction of each target rolling pass; Determining difference data based on the temporary reductions of all the target rolling passes and the initial reductions of the corresponding target rolling passes; Dividing the difference data according to the corresponding pass allocation rate, and updating the initial reduction of the corresponding non-target rolling pass according to the divided data to obtain the target reduction of the non-target rolling pass; When the target reduction of the non-target rolling pass is less than or equal to the preset threshold, the target reduction is used as the first reduction of the non-target rolling pass, and the countermeasure process is performed to obtain a temporary reduction of the non-target rolling pass; Determining a width expansion amount corresponding to the rolling pass according to the temporary reduction amount of the non-target rolling pass; updating the total width reduction according to all the width expansion amounts, and repeating the steps after comparing the updated total width reduction with the target width expansion data until a stop condition is met, thereby obtaining a temporary reduction for the non-target rolling pass; The target rolling pass is any of the rolling passes; the width expansion amount is the width expansion of the rolling pass after the dog bone is generated by the vertical roller mill and then the horizontal rolling mill is used to press it down.

[0073] Specifically, when the initial reduction amount of some passes exceeds the preset threshold, and the initial reduction amount of other passes is less than or equal to the preset threshold, the preset threshold is used as the first reduction amount of the pass exceeding the threshold, and a countermeasure process is performed to obtain the temporary reduction amount of these passes.

[0074] The difference data between the temporary reduction and the initial reduction for these target passes are calculated.

[0075] The difference data is distributed to non-target passes according to the pass distribution ratio, and the initial reduction of the non-target passes is updated to obtain the target reduction of the non-target passes.

[0076] If the target reduction amount of the non-target pass is less than or equal to the preset threshold, the target reduction amount is used as the first reduction amount of the non-target pass, and the countermeasure process is executed to obtain the temporary reduction amount of the non-target pass.

[0077] The corresponding width expansion is determined based on the temporary reduction of the non-target pass. The width expansion refers to the width expansion of the rolled piece when it passes through the horizontal rolling mill after the dog bone deformation caused by the vertical rolling mill.

[0078] The total width reduction is updated according to all width expansion amounts, and the step of comparing the updated total width reduction with the target width expansion data is repeated until the stop condition is met, thereby obtaining the final temporary reduction of the non-target pass.

[0079] In the above process, when the initial reduction of some passes exceeds the preset threshold, the distribution of reduction is optimized by adjusting the reduction of these passes and reasonably distributing the difference to other passes, ensuring the coordination and efficiency of the entire rolling process.

[0080] This method can adapt to varying production needs and process conditions. Whether the initial reduction in some passes exceeds a threshold or other complex situations arise, the reduction can be flexibly adjusted to meet process requirements, enhancing process flexibility and adaptability. By updating the total width reduction based on the width expansion and repeating the comparison and adjustment steps until the stopping condition is met, dynamic optimization of the rolling process is achieved, ensuring the efficiency and accuracy of the entire process.

[0081] Optionally, obtaining the total width expansion and target width expansion data of the slab to be rolled includes: Acquire the size data of the slab to be rolled and the parameter configuration data of the horizontal rolling mill, wherein the size data includes the initial size data and the width of the intermediate slab; Determining the total width expansion of the slab to be rolled according to the initial size data and the parameter configuration data; Target width data is obtained according to the intermediate billet width and the initial size data.

[0082] Specifically, the initial dimensional data of the slab to be rolled is obtained, including initial thickness, initial width, and intermediate bar width. The parameter configuration data for the horizontal rolling mill is also obtained, including roll diameter, roll radius, rolling speed, reduction, friction coefficient, etc. This data is obtained from the mill's control system or process design documentation. Based on the initial dimensional data and parameter configuration data, the total width expansion of the slab to be rolled is calculated. The total width expansion refers to the increase in width of the slab after rolling in the horizontal rolling mill, with the vertical mill inoperative. For example, target width expansion = intermediate bar width - initial width.

[0083] By acquiring detailed dimensional data and parameter configuration data, the total width and target width can be accurately calculated. This provides an accurate basis for subsequent process parameter adjustments, ensuring the accuracy and stability of the rolling process.

[0084] Optionally, updating the total width reduction amount according to all the width expansion amounts includes: Determining the outlet width of the final rolling pass according to all the width expansion amounts, and obtaining a target width expansion amount according to the outlet width of the final rolling pass and the intermediate billet width; The current total width reduction amount is updated according to the target width expansion amount.

[0085] Specifically, first, the exit width of the final rolling pass is determined based on all width expansions. Width expansion refers to the width expansion of the rolled piece when it passes through the horizontal rolling mill after undergoing dogbone deformation under the pressure of the vertical rolling mill. The calculation formula is as follows: B 出口 =B 中间坯 +∑Δb 回展 ; Among them, B出口 is the exit width of the last rolling pass, B 中间坯 is the width of the intermediate billet, Δb 回展 It is the width expansion amount of each rolling pass.

[0086] The target width expansion is calculated based on the exit width of the final rolling pass and the intermediate billet width. The target width expansion refers to the width increase that needs to be achieved in the subsequent rolling process in order to achieve the final required width. The calculation formula is as follows: ; Based on the calculated target width expansion, update the current total width reduction. The total width reduction refers to the total width that needs to be reduced by the vertical roller mill during the subsequent rolling process. The update formula is as follows: ΔB 总 =ΔB 当前 +Δb 目标 ; Where ΔB 总 is the updated total width reduction, ΔB 当前 is the current total width reduction.

[0087] By updating the total width reduction in real time, the width change during the rolling process can be more precisely controlled, ensuring the dimensional accuracy of the final product and reducing scrap due to width deviation. Dynamic adjustment of the total width reduction also makes the rolling process more flexible, better adapting to different production needs and product specifications, improving production efficiency and reducing resource waste.

[0088] Adjustments are made based on the actual width expansion during the rolling process, allowing the production process to better cope with changing production conditions and product requirements, and enhancing the adaptability and flexibility of the process.

[0089] And reasonably distribute the reduction amount and width change to avoid excessive reduction in local passes, reduce equipment wear and failure risks, extend equipment service life, and reduce maintenance costs.

[0090] This process ensures the accuracy and flexibility of the rolling process by dynamically adjusting and optimizing rolling parameters, improves product quality, reduces production costs, and enhances the adaptability of the production process.

[0091] Optionally, the stop condition includes that the target width expansion satisfies a width control index and a preset number of cycles.

[0092] Optionally, the process of obtaining the preset threshold includes: Determining the maximum reduction corresponding to each rolling pass according to the current thickness of the slab to be rolled in each rolling pass of the vertical rolling mill; Obtaining the maximum reduction of the vertical rolling mill; The corresponding preset threshold is determined according to the maximum reduction of each rolling pass and the maximum reduction of the vertical rolling mill.

[0093] Specifically, the maximum reduction required for each pass is calculated based on the current thickness of the slab being rolled at each rolling pass. This calculation takes into account multiple factors, including the slab's material, temperature, and mill performance, to ensure the feasibility and safety of the rolling process. Simply put, the maximum reduction the vertical mill can achieve in each pass is determined based on the current slab thickness. For example, a value of 0.4-0.6 times the thickness of the slab being rolled can be used.

[0094] Secondly, the maximum reduction of the vertical roller mill itself is obtained. This parameter is determined by the equipment performance and design specifications of the rolling mill. It represents the maximum reduction capacity that the rolling mill can achieve under optimal working conditions and reflects the hardware upper limit of the rolling mill.

[0095] Finally, the maximum reduction for each rolling pass is combined with the maximum reduction for the vertical mill to determine a corresponding preset threshold, typically the smallest of the two. This threshold can be considered a benchmark, taking into account both the specific conditions of each pass and the overall capabilities of the mill, providing a critical reference standard for subsequent rolling processes. This ensures that, during actual rolling, the reduction setting meets process requirements while remaining within the equipment's tolerances.

[0096] By accurately determining the preset thresholds for each rolling pass, we can ensure that the reduction in each pass is within a reasonable range, effectively improving rolling accuracy. This helps produce products with more precise dimensions and better surface quality, meeting customer demand for high-quality products.

[0097] Taking into account the maximum reduction of the vertical mill and the specific conditions of each pass, the equipment overload caused by excessive reduction is avoided. This helps to reduce equipment failure rate, reduce maintenance costs, extend equipment service life, and ensure production continuity.

[0098] This provides a scientific reference for the rolling process, making the setting of process parameters more reasonable. This not only helps to improve rolling efficiency, reduce unnecessary rolling passes and energy consumption, but also optimizes the entire production process, improving production efficiency and resource utilization.

[0099] At the same time, the preset threshold can be flexibly adjusted according to different slab thicknesses and rolling requirements. This enables the production process to better adapt to the production needs of multiple varieties and small batches, improving production flexibility and market competitiveness.

[0100] Some specific embodiments, such as Figure 6As shown, starting the rolling calculation, that is, the process flow configuration method of the roughing mill group of the hot rolling production line includes: 1. Start rolling calculation: start the calculation of the entire rolling process, that is, the process flow configuration method of the roughing mill group of the hot rolling production line.

[0101] 2. Obtain initial data: Collect the initial dimensions of the slab to be rolled (such as thickness and width), the parameters of the horizontal rolling mill (such as roll diameter, total number of passes, thickness at the exit of each pass, and other operating data), and the parameters of the vertical rolling mill (such as roll diameter, corresponding total number of passes, and other operating data).

[0102] 3. Determine the maximum reduction: According to the slab material, temperature and rolling mill specifications, determine the maximum reduction of each pass of the vertical roller mill. For example, you can choose 0.4 to 0.6 times the thickness of the rolled product (slab to be rolled) in the corresponding pass. 4. Obtain the maximum reduction of the vertical roller mill: clarify the maximum reduction capacity allowed by the vertical roller mill design.

[0103] 5. Determine the preset threshold: Based on the maximum reduction of each pass and the maximum reduction of the rolling mill as a whole, set the preset threshold for reduction.

[0104] 6. Calculate the total width expansion: Based on the initial data and rolling mill parameters, estimate the total width expansion of the slab when the horizontal rolling mill works alone.

[0105] 7. Compare the width expansion with the target value: Compare the calculated total width expansion with the target width expansion data.

[0106] 8. Decide whether to use the vertical roller mill: Yes: If the total width exceeds the target value, go to the next step.

[0107] No: If it does not exceed, the calculation ends and the vertical roller mill does not need to be involved.

[0108] 9. Determine the initial reduction for each pass of the vertical roller mill: Set the initial reduction for each pass of the vertical roller mill based on the total width reduction and pass distribution ratio.

[0109] 10. Check the initial pressure reduction and threshold: Compare the initial pressure reduction of each pass with the preset threshold.

[0110] 11. Adjust the amount of pressure: Yes: If the reduction in all passes exceeds the threshold, the countermeasure process is executed, the first reduction is set according to the threshold, and the reduction is recalculated according to the equipment limit.

[0111] No: Go to the next step.

[0112] 12. Handling of situations where some passes exceed the threshold: If the reduction in some passes exceeds the threshold, only these passes are adjusted and the difference is redistributed to other passes.

[0113] Update non-target pass reduction: Update the non-target pass reduction based on the adjusted data.

[0114] Check the non-target pass reduction: compare the non-target pass reduction with the threshold again.

[0115] 15. Determine the final reduction: If the reduction meets the requirements, the temporary reduction for each pass is determined through the countermeasure process, and the total width reduction is updated according to the width expansion amount.

[0116] 16. Loop optimization: Repeat the comparison and adjustment steps until the stop condition is met and the final reduction is obtained.

[0117] 17. End calculation: Complete all calculation steps and end the rolling calculation process.

[0118] The final configuration result is as follows Figure 7 As shown, Figure 3 Calculation results of the layout type vertical roller mill width reduction procedure of 100mm (the result of executing the process flow configuration method of the roughing mill group of the hot rolling production line).

[0119] An embodiment of the present invention provides a process flow configuration system for a roughing mill group of a hot rolling production line, comprising a memory and a processor; the memory is used to store a computer program; the processor is used to implement the process flow configuration method for the roughing mill group of a hot rolling production line as described above when executing the computer program.

[0120] An embodiment of the present invention provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the process flow configuration method of the roughing mill group of a hot rolling production line as described above is implemented.

[0121] A process flow configuration system for a roughing mill of a hot rolling mill line that can serve as a server or client of the present invention will now be described, which is an example of a hardware device that can be applied to various aspects of the present invention. The process flow configuration system for a roughing mill of a hot rolling mill line is intended to represent various forms of digital electronic computer devices, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The process flow configuration system for a roughing mill of a hot rolling mill line can also represent various forms of mobile devices, such as personal digital assistants, cellular phones, smart phones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the present invention described and / or required herein.

[0122] The process flow configuration system for the roughing mill of a hot rolling mill line includes a computing unit that can perform various appropriate actions and processes based on computer programs stored in read-only memory (ROM) or loaded from the storage unit into random access memory (RAM). The RAM also stores various programs and data required for equipment operation. The computing unit, ROM, and RAM are interconnected via a bus. Input / output (I / O) interfaces are also connected to the bus.

[0123] Those skilled in the art will appreciate that all or part of the processes in the above-described method embodiments can be implemented by instructing the relevant hardware through a computer program. The program can be stored in a computer-readable storage medium. When executed, the program can include the processes in the above-described method embodiments. The storage medium can be a magnetic disk, an optical disk, a read-only memory (ROM), or a random access memory (RAM). In this application, the units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, i.e., they may be located in one location or distributed across multiple network elements. Some or all of these units can be selected based on actual needs to achieve the objectives of the embodiments of the present invention. Furthermore, the functional units in the various embodiments of the present invention can be integrated into a single processing unit, each unit can exist physically separately, or two or more units can be integrated into a single unit. These integrated units can be implemented in either hardware or software functional units.

[0124] Although the present invention is disclosed as above, the protection scope of the present invention is not limited thereto. Those skilled in the art may make various changes and modifications without departing from the spirit and scope of the present invention, and these changes and modifications will fall within the protection scope of the present invention.

Claims

1. A process flow configuration method for a roughing mill group of a hot rolling production line, characterized in that: Applied to a roughing mill group, the roughing mill group includes an edger mill, and the process flow configuration method of the roughing mill group of the hot rolling production line includes: Obtaining the total width expansion and target width expansion data of the slab to be rolled, and comparing the total width expansion with the target width expansion data, When the total width expansion is greater than the target width expansion data, the total width reduction of the vertical rolling mill is obtained according to the total width expansion, and the process parameter configuration process of the vertical rolling mill is executed to obtain the temporary reduction of each rolling pass of the vertical rolling mill; The process parameter configuration process of the vertical roller mill includes: The initial reduction of each rolling pass of the vertical rolling mill is obtained according to the total width reduction and each preset pass distribution ratio. The comparison result is obtained by comparing the initial reduction of each rolling pass of the vertical roller mill with a preset threshold value. Adjusting the initial reduction of each rolling pass of the vertical rolling mill according to the comparison result to obtain a temporary reduction of each rolling pass of the vertical rolling mill; The final reduction amount of each rolling pass of the vertical rolling mill is determined according to each of the temporary reduction amounts.

2. The process configuration method of the roughing mill group of the hot rolling production line according to claim 1, characterized in that: The step of adjusting the initial reduction of each rolling pass of the vertical rolling mill according to the comparison result to obtain the temporary reduction of each rolling pass of the vertical rolling mill comprises: When the initial reduction of each rolling pass of the vertical rolling mill is greater than the preset threshold, Using the preset threshold as the first reduction of each rolling pass of the vertical rolling mill, and executing a countermeasure process; The countermeasure process includes: Determine the rolling force, rolling torque and motor power corresponding to the rolling pass according to each of the first reductions; The rolling force, the rolling torque and the motor power are judged respectively according to corresponding preset limit values to obtain a judgment result, and a temporary reduction amount of the vertical roller mill corresponding to the rolling pass is determined according to the judgment result.

3. The process flow configuration method of the roughing mill group of the hot rolling production line according to claim 2, characterized in that: Determining the temporary reduction of the vertical rolling mill corresponding to the rolling pass according to the judgment result includes: If at least one of the rolling force, the rolling torque and the motor power exceeds the corresponding preset limit, a calculation is performed based on the corresponding preset limit to obtain a temporary reduction of the edger mill corresponding to the rolling pass; When the rolling force, the rolling torque and the motor power are all less than or equal to the corresponding preset limit values, the preset threshold value is used as the temporary reduction amount of the vertical rolling mill corresponding to the rolling pass.

4. The process flow configuration method of the roughing mill group of the hot rolling production line according to claim 2, characterized in that: The step of adjusting the initial reduction of each rolling pass of the vertical rolling mill according to the comparison result to obtain the temporary reduction of each rolling pass of the vertical rolling mill further includes: When the initial reduction of each target rolling pass is greater than the preset threshold, and the initial reduction of the non-target rolling pass is less than or equal to the preset threshold, the preset threshold is used as the first reduction of each target rolling pass, and the countermeasure process is performed to obtain a temporary reduction of each target rolling pass; Determining difference data based on the temporary reductions of all the target rolling passes and the initial reductions of the corresponding target rolling passes; Dividing the difference data according to the corresponding pass allocation rate, and updating the initial reduction of the corresponding non-target rolling pass according to the divided data to obtain the target reduction of the non-target rolling pass; When the target reduction of the non-target rolling pass is less than or equal to the preset threshold, the target reduction is used as the first reduction of the non-target rolling pass, and the countermeasure process is performed to obtain a temporary reduction of the non-target rolling pass; Determining a width expansion amount corresponding to the rolling pass according to the temporary reduction amount of the non-target rolling pass; updating the total width reduction according to all the width expansion amounts, and repeating the steps after comparing the updated total width reduction with the target width expansion data until a stop condition is met, thereby obtaining a temporary reduction for the non-target rolling pass; The target rolling pass is any of the rolling passes; the width expansion amount is the width expansion of the rolling pass after the dog bone is generated by the vertical roller mill and then the horizontal rolling mill is used to press it down.

5. The process flow configuration method of the roughing mill group of the hot rolling production line according to claim 4, characterized in that: The method of obtaining the total width expansion and target width expansion data of the slab to be rolled includes: Acquire the size data of the slab to be rolled and the parameter configuration data of the horizontal rolling mill, wherein the size data includes the initial size data and the width of the intermediate slab; Determining the total width expansion of the slab to be rolled according to the initial size data and the parameter configuration data; Target width data is obtained according to the intermediate billet width and the initial size data.

6. The process flow configuration method of the roughing mill group of the hot rolling production line according to claim 5, characterized in that: The updating of the total width reduction amount according to all the width expansion amounts includes: Determining the outlet width of the final rolling pass according to all the width expansion amounts, and obtaining a target width expansion amount according to the outlet width of the final rolling pass and the intermediate billet width; The current total width reduction amount is updated according to the target width expansion amount.

7. The process configuration method of the roughing mill group of the hot rolling production line according to claim 4, characterized in that: The stopping condition includes that the target width expansion meets the width control index and the preset number of cycles.

8. The process flow configuration method of the roughing mill group of the hot rolling production line according to claim 1, characterized in that: The process of obtaining the preset threshold includes: Determining the maximum reduction corresponding to each rolling pass according to the current thickness of the slab to be rolled in each rolling pass of the vertical rolling mill; Obtaining the maximum reduction of the vertical rolling mill; The corresponding preset threshold is determined according to the maximum reduction of each rolling pass and the maximum reduction of the vertical rolling mill.

9. A process flow configuration system for a roughing mill group of a hot rolling production line, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the process flow configuration method of the roughing mill group of the hot rolling production line according to any one of claims 1 to 8 is implemented.

10. A computer-readable storage medium, characterized in that The storage medium stores a computer program, and when the computer program is executed by the processor, the process flow configuration method of the roughing mill group of the hot rolling production line according to any one of claims 1 to 8 is implemented.

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