A rapid handling and control method and system for finishing mill shutdown faults

Abstract

This invention provides a rapid handling and control method and system for finishing mill shutdown faults, employing different automatic interlocking control programs for different steel stacking methods under different circumstances. It enables rapid response measures, achieving quick accident handling through automatic control, eliminating the need for manual judgment and operation, and avoiding the adverse factors such as long operator response times and operational errors under emergency conditions. When a portion of the hot-rolled strip has already rolled out to F7, the strip within the stand is automatically pulled off by the rear stand mill, achieving partial coiling and producing some finished products, reducing losses; simultaneously, it prevents the faulty strip from remaining in the stand, saving the necessary roll changing operation after an accident. The remaining faulty strip in the stand is quickly reversed back onto the pusher roller table by manual operation, pushed off the rolling line, and restores normal rolling order; this avoids the time spent on manual cutting, saving significant accident handling time and improving unit operating efficiency.

Description

Technical Field

[0001] This invention relates to the field of hot-rolled strip steel rolling production operation and electrical automation control technology, and in particular to a rapid handling and control method and system for finishing mill shutdown faults. Background Technology

[0002] With the advancement of industrial technology, the level of automation in the production of hot-rolled strip steel products has been increasing year by year, achieving fully automated steel rolling through electrical automation control programs. However, the harsh environment during the hot-rolled strip steel production process—high temperature, high dust, and high humidity—significantly impacts the normal operation of electrical components. Simultaneously, the aging of hardware in the primary and secondary automation systems of the rolling line leads to a year-on-year increase in failure rates if not updated promptly. To maximize efficiency, the variety and specifications produced on the production line are expanding annually, moving towards diversification. However, the overload operation of the rolling mill during the production of extreme specifications and high-strength steel products causes significant damage to electrical and mechanical equipment, further increasing the failure rate. Given the significant cost pressures on enterprises for survival and development, rapid handling of malfunctions, minimizing downtime, and improving unit operating efficiency place high demands on rolling line workers. Furthermore, handling steel pile-up accidents must prevent secondary losses and avoid further escalation; therefore, minimizing post-malfunction losses is also a key consideration for operators.

[0003] Currently, in the hot rolling mill industry, once a steel strip pile-up accident occurs, an emergency stop operation is immediately performed. The strip steel piles up inside the stand, and after manual segmentation and cutting of the steel plates, they are lifted out of the stand in sections. This process takes a long time and seriously affects the unit's operating efficiency. At the same time, it damages the work rolls inside the stand, and after the piled-up scrap plates are lifted out, a roll replacement operation must be performed. Due to improper operation, work roll scrapping and equipment damage occur frequently, causing huge losses to enterprises. Summary of the Invention

[0004] To address the technical problems raised in the background, this invention provides a rapid handling and control method and system for finishing mill shutdown faults. It provides operational methods for rapid emergency response to shutdown faults occurring under various circumstances during the operation of the strip mill, precisely and quickly preventing the further escalation of losses after a shutdown accident. An automatic interlocking control program is used for different steel stacking methods under different circumstances, enabling rapid restoration of normal rolling order, saving the necessary roll changing procedures after an accident, and preventing further expansion of losses. Simultaneously, this systematic approach to handling steel stacking significantly reduces the time spent on handling stacked steel compared to previous methods, improving the unit's operating efficiency.

[0005] To achieve the above objectives, the present invention employs the following technical solution:

[0006] A rapid handling and control method for finishing mill shutdown faults employs different automatic interlocking control programs for different steel stacking methods under different circumstances; including the following:

[0007] Scenario 1: The strip is threaded into the finishing mill but has not rolled out of the F7 stand. At this time, the finishing mill issues a stop signal.

[0008] Handling and control methods: The roll gap of the finishing mill stand is opened, the water spray valve is opened to cool the strip, and the strip is manually returned to the pusher roller table and pushed away from the rolling line.

[0009] Scenario 2: The strip is threaded in the finishing mill and a strip is rolled out of stand F7 but not coiled. At this time, one of the stands F1-F4 of the finishing mill issues a stop signal.

[0010] Handling and control methods: The finishing mills F1-F4 are shut down, while F5-F7 are rolled normally to break the strip and achieve partial coiling; the roll gaps of each stand in F1-F4 are raised, the water spray valves of the F1-F4 mills are opened, and the remaining strip in the finishing mills is manually pushed back to the pusher roller table and removed from the rolling line.

[0011] Scenario 3: The strip is threaded in the finishing mill and a strip is rolled out of the F7 stand, but coiling has not been achieved. At this time, the coiler sends a stop signal.

[0012] Handling and control methods: The finishing mill operates normally, the laminar flow cooling upper manifold is raised, and the strip steel accumulates on the laminar flow cooling roller table;

[0013] Scenario 4: The strip is threaded in the finishing mill and a strip is rolled out of stand F7 and coiled. At this time, a stop signal is issued by a stand F1-F4 of the finishing mill.

[0014] Handling and control methods: The finishing mills F1-F4 are shut down, while F5-F7 are rolled normally to break the strip and achieve partial coiling; the roll gaps of each stand in F1-F4 are raised, the water spray valves of the F1-F4 mills are opened, and the remaining strip in the finishing mills is manually pushed back to the pusher roller table and removed from the rolling line.

[0015] Scenario 5: The strip is threaded in the finishing mill and a strip is rolled out of the F7 stand and coiled. At this time, the coiler sends a stop signal.

[0016] Handling and control methods: The finishing mill operates normally, the laminar flow cooling upper manifold is raised, and the strip steel accumulates on the laminar flow cooling roller table;

[0017] Scenario 6: The strip steel is ejected from some stands of the finishing mill. At this time, a stop signal is issued by a certain stand of the finishing mill (F1-F4).

[0018] Handling and control methods: The finishing mills F1-F4 are shut down, while F5-F7 are rolled normally to break the strip and achieve partial coiling; the roll gaps of each stand in F1-F4 are raised, the water spray valves of the F1-F4 mills are opened, and the remaining strip in the finishing mills is manually pushed back to the pusher roller table and removed from the rolling line.

[0019] Scenario 7: The strip steel is ejected from some stands of the finishing mill, at which point the coiler issues a stop signal;

[0020] Handling and control methods: The finishing mill operates normally, the laminar flow cooling upper manifold is raised, and the strip steel accumulates on the laminar flow cooling roller table.

[0021] Furthermore, the control flow for scenario 1 is as follows: 1) a fault signal is initiated for the finishing mill; 2) the finishing mill is shut down; 3) the roll gaps of each stand are raised; 4) the water spray valves are opened.

[0022] Furthermore, the control flow for scenario 2 is as follows: 1) a fault signal is initiated for the finishing mill; 2) F1-F4 mills are shut down; 3) F5-F7 mills are rolled normally; 4) the coiler is wound normally; 5) the roll gaps of each stand in F1-F4 are raised; 6) the water spray valves of F1-F4 mills are opened.

[0023] Furthermore, the control flow for scenario 3 is as follows: 1) a coiler fault signal is initiated; 2) the laminar flow cooling upper manifold is lifted; 3) the finishing mill operates normally.

[0024] Furthermore, the control flow for scenario 4 is as follows: 1) a finishing mill fault signal is initiated; 2) F1-F4 units are shut down; 3) F5-F7 units are rolled normally; 4) the coiler is wound normally; 5) the roll gaps of each stand in F1-F4 are raised; 6) the water spray valves in F1-F4 are opened.

[0025] Furthermore, the control flow for scenario 5 is as follows: 1) a winding fault signal is initiated; 2) the laminar flow cooling upper manifold is lifted; 3) the finishing mill proceeds with normal rolling.

[0026] Furthermore, the control flow for scenario 6 is as follows: 1) a finishing mill fault signal is initiated; 2) F1-F4 units are shut down; 3) F5-F7 units are rolled normally; 4) coiling is rolled normally; 5) the roll gaps of each stand in F1-F4 are raised; 6) the water spray valves in F1-F4 are opened.

[0027] Furthermore, the control flow for scenario 7 is as follows: 1) a winding fault signal is initiated; 2) the laminar flow cooling upper manifold is lifted; 3) the finishing mill proceeds with normal rolling.

[0028] The present invention also provides a control system for the rapid handling and control method for a finishing mill shutdown fault, the control system including a PLC and a host computer connected thereto, the PLC system being used to control the finishing mill unit, coiling equipment and laminar flow cooling equipment, and the rapid handling and control method for a finishing mill shutdown fault being loaded into the internal programs of the PLC and the host computer.

[0029] Compared with the prior art, the beneficial effects of the present invention are:

[0030] This invention employs an automated interlocking emergency response procedure to rapidly address seven different scenarios. Through automated control, it achieves rapid accident handling without requiring manual judgment or operation, avoiding the adverse effects of long operator response times and operational errors under emergency conditions. When a portion of the hot-rolled strip has already rolled out to F7, whether coiled or not, a steel pile-up accident caused by a stop signal is partially coiled by automatically pulling the strip within the stands of the subsequent mill stands. This allows for partial production of finished products, reducing losses. Simultaneously, it prevents the damaged strip from remaining in the stands, saving the necessary roll-changing process after an accident and avoiding damage to the rolls in operation. The remaining damaged strip in the stands is quickly pushed back onto the pusher roller table by manual operation, removing it from the rolling line and restoring normal rolling order. This avoids the time required for manual cutting, saving significant accident handling time and improving unit operating efficiency. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of a shutdown fault in scenario 1 of the present invention and the corresponding processing and control flow;

[0032] Figure 2 This is a schematic diagram of a shutdown fault in scenario 2 of the present invention and the corresponding processing and control flow;

[0033] Figure 3 This is a schematic diagram of a shutdown fault in scenario 3 of the present invention and the corresponding processing and control flow;

[0034] Figure 4 This is a schematic diagram of a shutdown fault in scenario 4 of the present invention and the corresponding processing and control flow;

[0035] Figure 5 This is a schematic diagram of a shutdown fault in scenario 5 of the present invention and the corresponding processing and control flow;

[0036] Figure 6 This is a schematic diagram of a shutdown fault in scenario 6 of the present invention and the corresponding processing and control flow;

[0037] Figure 7 This is a schematic diagram of a shutdown fault in scenario 7 of the present invention and the corresponding processing and control flow. Detailed Implementation

[0038] The specific embodiments provided by the present invention will be described in detail below with reference to the accompanying drawings.

[0039] A rapid handling and control method for finishing mill shutdown faults employs different automatic interlocking control programs for different steel stacking methods under different circumstances; including the following:

[0040] Scenario 1: The strip is threaded into the finishing mill but has not rolled out of the F7 stand. At this time, the finishing mill issues a stop signal.

[0041] Handling and control methods: The roll gap of the stand is opened quickly, the water spray valve is opened, the strip is cooled quickly, and the strip is manually returned to the pusher roller table and pushed away from the rolling line.

[0042] Scenario 2: The strip is threaded in the finishing mill and a strip is rolled out of stand F7 but not coiled. At this time, a stop signal is issued by a stand F1-F4 of the finishing mill.

[0043] Handling and control methods: The finishing mills F1-F4 are shut down, while F5-F7 are rolled normally to break the strip and achieve partial coiling; the roll gaps of each stand in F1-F4 are raised, the water spray valves of the F1-F4 mills are opened, and the remaining strip in the finishing mills is manually pushed back to the pusher roller table and removed from the rolling line.

[0044] Scenario 3: The strip is threaded in the finishing mill and a strip is rolled out of the F7 stand, but coiling has not been achieved. At this time, the coiler sends a stop signal.

[0045] Handling and control methods: The finishing mill operates normally, the laminar flow cooling upper manifold is raised, and the strip steel accumulates on the laminar flow cooling roller table;

[0046] Scenario 4: The strip is threaded in the finishing mill and a strip is rolled out of stand F7 and coiled. At this time, a stop signal is issued by a stand F1-F4 of the finishing mill.

[0047] Handling and control methods: The finishing mills F1-F4 are shut down, while F5-F7 are rolled normally to break the strip and achieve partial coiling; the roll gaps of each stand in F1-F4 are raised, the water spray valves of the F1-F4 mills are opened, and the remaining strip in the finishing mills is manually pushed back to the pusher roller table and removed from the rolling line.

[0048] Scenario 5: The strip is threaded in the finishing mill and a strip is rolled out of the F7 stand and coiled. At this time, the coiler sends a stop signal.

[0049] Handling and control methods: The finishing mill operates normally, the laminar flow cooling upper manifold is raised, and the strip steel accumulates on the laminar flow cooling roller table;

[0050] Scenario 6: The strip steel is ejected from some stands of the finishing mill. At this time, a stop signal is issued by a certain stand of the finishing mill (F1-F4).

[0051] Handling and control methods: The finishing mills F1-F4 are shut down, while F5-F7 are rolled normally to break the strip and achieve partial coiling; the roll gaps of each stand in F1-F4 are raised, the water spray valves of the F1-F4 mills are opened, and the remaining strip in the finishing mills is manually pushed back to the pusher roller table and removed from the rolling line.

[0052] Scenario 7: The strip steel is ejected from some stands of the finishing mill, at which point the coiler issues a stop signal;

[0053] Handling and control methods: The finishing mill operates normally, the laminar flow cooling upper manifold is raised, and the strip steel accumulates on the laminar flow cooling roller table.

[0054] like Figure 1-7 As shown, the specific implementation process of the control flow for each scenario is as follows (the dashed box in the figure indicates the fault location):

[0055] 1. Control process for scenario 1: Fault signal initiated - unit shutdown - roller gaps of each frame lifted - water spray valves opened.

[0056] 2. Situation 2 control process: Fault signal initiated - F1-F4 units shut down - F5-F7 normal rolling - normal coiling - F1-F4 roll gaps lifted - F1-F4 water spray valves opened.

[0057] 3. Situation 3 control process: Coiler fault signal initiated - laminar flow cooling upper manifold lifted - finishing mill normal rolling.

[0058] 4. Control process for scenario 4: Finishing mill fault signal initiated — F1-F4 units shut down — F5-F7 normal rolling — coiling normal coiling — roll gap of each stand of F1-F4 raised — water spray valve of F1-F4 opened.

[0059] 5. Situation 5 control process: Coiling fault signal initiated - laminar flow cooling upper manifold lifted - finishing mill normal rolling.

[0060] 6. Control process for scenario 6: Finishing mill fault signal initiated — F1-F4 units shut down — F5-F7 normal rolling — coiling normal coiling — roll gap of each stand of F1-F4 raised — water spray valve of F1-F4 opened.

[0061] 7. Situation 7 control process: Coiling fault signal initiated - laminar flow cooling upper manifold lifted - finishing mill normal rolling.

[0062] This invention also provides a control system for the rapid handling and control method for finishing mill shutdown faults, the control system including a PLC and a host computer connected thereto, the PLC system being used to control the finishing mill unit, coiling equipment and laminar flow cooling equipment, and the rapid handling and control method for finishing mill shutdown faults being loaded into the internal programs of the PLC and the host computer.

[0063] This invention employs an automated interlocking emergency response procedure to rapidly address seven different scenarios. Through automated control, it achieves rapid accident handling without requiring manual judgment or operation, avoiding the adverse effects of long operator response times and operational errors under emergency conditions. When a portion of the hot-rolled strip has already rolled out to F7, whether coiled or not, a steel pile-up accident caused by a stop signal is partially coiled by automatically pulling the strip within the stands of the subsequent mill stands. This allows for partial production of finished products, reducing losses. Simultaneously, it prevents the damaged strip from remaining in the stands, saving the necessary roll-changing process after an accident and avoiding damage to the rolls in operation. The remaining damaged strip in the stands is quickly pushed back onto the pusher roller table by manual operation, removing it from the rolling line and restoring normal rolling order. This avoids the time required for manual cutting, saving significant accident handling time and improving unit operating efficiency.

[0064] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0065] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A rapid handling and control method for finishing mill shutdown faults, characterized in that, Different automatic interlocking control methods are adopted for different steel stacking methods under different situations; including the following: Scenario 1: The strip is threaded into the finishing mill but has not rolled out of the F7 stand. At this time, the finishing mill issues a stop signal. Handling and control methods: The roll gap of the finishing mill stand is opened, the water spray valve is opened to cool the strip, and the strip is manually returned to the pusher roller table and pushed away from the rolling line. Scenario 2: The strip is threaded in the finishing mill and a strip is rolled out of stand F7 but not coiled. At this time, one of the stands F1-F4 of the finishing mill issues a stop signal. Handling and control methods: The finishing mills F1-F4 are shut down, while F5-F7 are rolled normally to break the strip and achieve partial coiling; the roll gaps of each stand in F1-F4 are raised, the water spray valves of the F1-F4 mills are opened, and the remaining strip in the finishing mills is manually pushed back to the pusher roller table and removed from the rolling line. Scenario 3: The strip is threaded in the finishing mill and a strip is rolled out of the F7 stand, but coiling has not been achieved. At this time, the coiler sends a stop signal. Handling and control methods: The finishing mill operates normally, the laminar flow cooling upper manifold is raised, and the strip steel accumulates on the laminar flow cooling roller table; Scenario 4: The strip is threaded in the finishing mill and a strip is rolled out of stand F7 and coiled. At this time, a stop signal is issued by a stand F1-F4 of the finishing mill. Handling and control methods: The finishing mills F1-F4 are shut down, while F5-F7 are rolled normally to break the strip and achieve partial coiling; the roll gaps of each stand in F1-F4 are raised, the water spray valves of the F1-F4 mills are opened, and the remaining strip in the finishing mills is manually pushed back to the pusher roller table and removed from the rolling line. Scenario 5: The strip is threaded in the finishing mill and a strip is rolled out of the F7 stand and coiled. At this time, the coiler sends a stop signal. Handling and control methods: The finishing mill operates normally, the laminar flow cooling upper manifold is raised, and the strip steel accumulates on the laminar flow cooling roller table; Scenario 6: The strip steel is ejected from some stands of the finishing mill. At this time, a stop signal is issued by a certain stand of the finishing mill (F1-F4). Handling and control methods: The finishing mills F1-F4 are shut down, while F5-F7 are rolled normally to break the strip and achieve partial coiling; the roll gaps of each stand in F1-F4 are raised, the water spray valves of the F1-F4 mills are opened, and the remaining strip in the finishing mills is manually pushed back to the pusher roller table and removed from the rolling line. Scenario 7: The strip steel is ejected from some stands of the finishing mill, at which point the coiler issues a stop signal; Handling and control methods: The finishing mill operates normally, the laminar flow cooling upper manifold is raised, and the strip steel accumulates on the laminar flow cooling roller table.

2. The rapid handling and control method for finishing mill shutdown faults according to claim 1, characterized in that, The control flow for scenario 1 is as follows: 1) A fault signal is initiated for the finishing mill; 2) The finishing mill is shut down; 3) The roll gaps of each stand are raised; 4) The water spray valves are opened.

3. The rapid handling and control method for finishing mill shutdown faults according to claim 1, characterized in that, The control flow for scenario 2 is as follows: 1) A fault signal is initiated for the finishing mill; 2) F1-F4 mills are shut down; 3) F5-F7 mills operate normally. 4) Normal winding; 5) Lift the roll gaps of each frame from F1 to F4; 6) Open the water spray valves of units F1 to F4.

4. The rapid handling and control method for finishing mill shutdown faults according to claim 1, characterized in that, The control flow for scenario 3 is as follows: 1) a coiler fault signal is initiated; 2) the laminar flow cooling upper manifold is lifted; 3) the finishing mill operates normally.

5. The rapid handling and control method for finishing mill shutdown faults according to claim 1, characterized in that, The control flow for scenario 4 is as follows: 1) A finishing mill fault signal is initiated; 2) Units F1-F4 are shut down; 3) Units F5-F7 are rolled normally. 4) Normal winding; 5) Lift the roll gaps of each frame from F1 to F4; 6) Open the water spray valves of F1 to F4.

6. The rapid handling and control method for finishing mill shutdown faults according to claim 1, characterized in that, The control flow for scenario 5 is as follows: 1) a winding fault signal is initiated; 2) the laminar flow cooling upper manifold is lifted; 3) the finishing mill proceeds with normal rolling.

7. The rapid handling and control method for finishing mill shutdown faults according to claim 1, characterized in that, The control flow for scenario 6 is as follows: 1) a finishing mill fault signal is initiated; 2) F1-F4 units are shut down; 3) F5-F7 units are rolled normally; 4) coiling is rolled normally; 5) the roll gaps of each stand in F1-F4 are raised; 6) the water spray valves in F1-F4 are opened.

8. The rapid handling and control method for finishing mill shutdown faults according to claim 1, characterized in that, The control flow for scenario 7 is as follows: 1) a winding fault signal is initiated; 2) the laminar flow cooling upper manifold is lifted; 3) the finishing mill proceeds with normal rolling.

9. A control system for a rapid handling and control method for a finishing mill shutdown fault as described in any one of claims 1-8, characterized in that, The control system includes a PLC system and a host computer connected thereto. The PLC system is used to control the finishing mill, coiling equipment and laminar flow cooling equipment. The PLC system and the host computer's internal program load the rapid handling control method for finishing mill shutdown faults as described in any one of claims 1-8.

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