A control method for avoiding red steel rear-end

Abstract

The application discloses a control method for avoiding red steel rear-end collision, and belongs to the technical field of steel rolling production, and solves the technical problem of red steel rear-end collision in double-high-line rolling. The method comprises the following steps: collecting a rising edge signal of red steel of a hot metal detector before rough rolling of lower steel; collecting a falling edge signal of red steel of a hot metal detector before rough rolling of upper steel; collecting a 10-second power-off delay interlocking signal of the falling edge signal of the hot detection signal before rough rolling of the upper steel; establishing an actual jump value of a time component when tail rough rolling of the upper steel is finished on the second stand; establishing an actual value of the time component when head rough rolling of the lower steel is finished on the second stand and performing value comparison; performing data tracking on a head-tail gap time of the two red steels being less than or equal to 7 seconds and forming an intermediate numerical variable; associating a control output for avoiding red steel rear-end collision in a small gap time of a fast tapping pace and a steel separating roller; and collecting the output interlocking signal of the small gap time of the fast tapping pace and the steel separating roller into a picture alarm and a high-speed data acquisition system.

Description

Technical Field

[0001] This invention relates to the field of steel rolling production technology, and more specifically, to a control method for preventing red-hot steel from colliding. Background Technology

[0002] In the double-high-speed wire rod rolling process, after the red-hot steel is heated by the heating system, it is transported to the five roughing rolling groups via ten sets of furnace exit rollers. After being rolled by the five roughing rolling groups, it enters the double-line steel separation roller process. The red-hot steel first passes through the intermediate roller group of the steel separation system through rolling tracking, and is then divided into single-line rolling and double-line rolling according to the subsequent rolling conditions.

[0003] The original design ensured smooth rolling under normal rolling conditions, with requirements for accelerating the rolling pace and stabilizing the rolling process. However, if the rolling pace is too fast and the steel output pace exceeds the preset limits, the gap between the hot steel and the intermediate rollers of the sorting roller group will be too small after the hot steel has passed through the roughing rolling mill. This can lead to an abnormal situation where the head of the next hot steel piece hits the tail of the previous one, causing a steel pile-up accident. This situation occurs under conditions of excessively fast rolling pace and errors in process operation. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to address the above-mentioned shortcomings of the prior art. The purpose of the present invention is to provide a control method to avoid rear-end collisions involving red-hot steel.

[0005] The technical solution of the present invention is: a control method for avoiding rear-end collisions involving red-hot steel, comprising the following steps:

[0006] Step 1. Collect the rising edge signal of the hot metal detector before roughing the next steel bar. Establish a pulse program system for the rising edge signal of the hot metal detector before roughing the next steel bar in the PLC control system of the double high-speed line. According to the production process, after the hot steel bar is heated in the heating furnace, the rolling line control system sends an automatic steel demand signal. The hot steel bar enters the furnace exit roller table through the continuously running furnace exit cantilever roller. When the head of the hot steel bar passes the hot metal detector before roughing the next steel bar, the hot metal detector immediately collects the steel bar head and generates a steel bar signal, and feeds it back to the digital input module of the PLC control system. This provides the PLC control system with the rising edge signal of the hot metal detector before roughing the next steel bar and assigns this rising edge signal to the intermediate variable in the program.

[0007] Step 2. Collect the falling edge signal of the hot metal detector before rough rolling of the red steel. Establish a pulse program system for the falling edge signal of the hot metal detector before rough rolling in the double high-speed line PLC1 control system. According to the production process, after the red steel is heated in the heating furnace, the rolling line control system sends an automatic steel demand signal. The red steel enters the furnace exit roller table through the continuously running furnace exit cantilever roller. When the tail of the red steel passes the hot metal detector before rough rolling, the hot metal detector immediately removes the steel signal generated at the tail of the red steel and feeds it back to the digital input module of the PLC control system. This provides the PLC control system with the falling edge pulse of the hot metal detector signal before rough rolling and assigns this falling edge signal to the intermediate variable in the program as the interlock control condition for the next step.

[0008] Step 3. Acquire the falling edge of the hot metal detector signal before rough rolling of the upper steel and 10-second power-off delay interlock signal. Based on the double high-speed wire rod rolling condition, according to the falling edge signal of the hot metal detector before rough rolling of the upper steel collected in Step 2, the pulse trigger condition for the tail of the upper steel to pass through the hot metal detector before rough rolling is used. Using the power-off delay function of the power-off delay timer S_OFFDT in the PLC control system, according to the control requirements of the on-site process production conditions and rolling rhythm, if the falling edge of the detection signal of the tail of the upper steel passes through the hot metal detector before rough rolling arrives, set the power-off delay timer S_OFFDT set in the program to 10 seconds for power-off delay, and store the output result in an intermediate variable register as a prerequisite for subsequent interlock control.

[0009] Step 4. Establish the actual jump value of the time component when the tail of the upper steel bar exits the second roughing mill stand. According to the process production conditions, there are often rolling stoppages for maintenance on site. At this time, the red steel needs to stay in the heating furnace for heat preservation treatment. After the upper red steel bar is rolled into the roughing mill and then ejected, the subsequent red steel bar will stay in the heating furnace for a long time. At this time, the time interval between the head and tail of the two red steel bars needs to be properly handled. Taking the steel presence signal of the red steel bar entering the second roughing mill stand as the reference, collect the ejection signal of the red steel bar entering the second roughing mill stand. Under the condition that all rolling mills are operating normally, use P The FC20 delay time function block inside the LC control system is set to a preset time of 500 seconds. This time is the preset time when the red steel rolled into the roughing mill 2 stands is thrown under all rolling mill operating conditions. At the same time, the real-time time value after the steel is thrown by the roughing mill 2 stands is recorded in the FC20 delay time function block and stored in the double-word variable point in the DB block. This is used as the gap time parameter between the head and tail of the two red steel bars to establish the actual jump value of the time component when the tail of the upper steel bar passes through the roughing mill 2 stands.

[0010] Step 5. Establish the actual value of the time component when the head of the lower steel bar is rolled into the second roughing mill stand and assign and compare the values. Based on the actual jump value of the time component when the tail of the upper steel bar is rolled out of the second roughing mill stand in Step 4, obtain the actual time jump value when the upper red steel bar is rolled out of the second roughing mill stand. It is also necessary to establish the actual value of the time component when the head of the lower red steel bar is rolled into the second roughing mill stand, so as to obtain the actual time gap value between the tail of the upper red steel bar and the head of the lower red steel bar.

[0011] Step Six. Track data on the time gap between the two red steel heads and tails being less than or equal to 7 seconds and form an intermediate numerical variable. According to the process production requirements, compare the actual value of the time component established in Step Five when the head of the next steel is rolled into the second roughing mill stand. In the PLC control system, collect the pre-set time of the FC20 delay time function block and collect the steel signal generated by the rolling of red steel into the second roughing mill stand. This steel signal generates a pulse variable and triggers the pre-set time of the FC20 delay time function block in Step Four. Assign this pre-set time to a DB variable point and define this DB variable point as the time gap between the two red steel heads and tails. Use this time gap as a reference. If the time gap between the two red steel heads and tails is less than or equal to 7 seconds, output the interlocking control condition of the time gap between the two red steel heads and tails being less than or equal to 7 seconds to an intermediate variable control point as the premise and basis for subsequent interlocking control.

[0012] Step 7. Corresponding to the control output for avoiding red-hot steel collision due to the fast steel tapping rhythm and small gap time of the steel separating rollers, based on the process production requirements and combining the above steps 1 to 6, we obtain the interlocking control program condition 1 and the series interlocking control program condition 2. Interlocking control program condition 1 is: during the 10-second power-off delay timer of the falling edge of the hot metal detector signal before the roughing of the upper steel, the following interlocking control program condition 2 is: if the hot metal detector before the roughing of the lower steel has a rising edge signal of red-hot steel, and during the 10-second power-off delay timer in interlocking control program condition 1, the hot metal detector before the roughing of the lower steel detects a rising edge signal of red-hot steel, this indicates a risk of red-hot steel collision due to the fast steel tapping rhythm and small gap time of the steel separating rollers. At this time, the signal indicating a risk of red-hot steel collision due to the small gap time of the steel separating rollers is output.

[0013] Combined with step six, data tracking is performed on the time gap between the two red steel heads and tails being less than or equal to 7 seconds, and intermediate numerical variables are formed. If the time gap between the two red steel heads and tails is less than or equal to 7 seconds, a signal is also output indicating that the steel rhythm is fast and the gap time between the steel rollers is small, which may lead to the risk of red steel rear-end collision. This achieves a double avoidance of red steel rear-end collision accidents.

[0014] Step 8. Collect the output interlock signal of the fast steel separation roller conveyor with small gap time associated with the steel output rhythm to the screen alarm and high-speed data acquisition system. In the alarm column of the main screen of the human-machine interface WINCC screen, display the screen alarm reminder of small gap time of the fast steel separation roller conveyor with yellow text, so as to promptly provide feedback to the process operators to control the production rhythm and avoid the accident of the head and tail of the red steel.

[0015] As a further improvement, in step one, the digital input / output module is a DI / DO module, which is used to receive switch signals from the field / output switch signals to the field devices; the DI module is used to receive various switch states from the electrical circuit, and the DO module is used to control the start and stop of the field solenoid valve or motor.

[0016] Furthermore, in step three, the power-off delay timer S_OFFDT is used to disconnect the output only after a certain delay when the input is disconnected; when the enable input is valid, the timer output status bit is immediately set to 1, and the current value is reset to 0; when the enable input is disconnected, the timer starts counting, the current value increments from 0, and when the current value reaches the preset value, the timer status bit is reset to 0 and the counting stops, while the current value is retained.

[0017] Furthermore, in step four, the FC20 delay time function block is a general delay time function block created in the PLC software control program by programming the enable terminal, input start terminal, time preset terminal, real-time variable value jump terminal and enable output terminal in a statement list manner, and these function terminals and control terminal components are compiled into a general delay time function block.

[0018] Furthermore, in step five, the steel presence signal generated by the rolling of red steel in the two roughing stands is first collected. This steel presence signal generates a pulse variable and simultaneously triggers the pre-set time of the FC20 delay time function block in step four. This pre-set time is assigned to a DB variable point, which is defined as the time gap between the head and tail of the two red steel bars. Using this time gap as a reference, if the time gap between the head and tail of the two red steel bars is greater than or equal to 100 seconds, it will be determined that the time gap between the head and tail of the two red steel bars is 100 seconds. If the time gap between the head and tail of the two red steel bars exceeds 100 seconds during normal rolling, it indicates that there is a temporary stop for rolling maintenance or a change from double-high wire rolling to single-wire rolling.

[0019] Furthermore, in step six, the pre-set time of the FC20 delay time function block is converted into data using the PLC control system. The pre-set time variable DB point of the FC20 delay time function block is converted into a real number through the program. The pre-set time variable DB point of the FC20 delay time function block is expressed in the form of time seconds. Finally, the pre-set time of the two red steel head and tail time gaps in this real number in seconds is expressed as an intermediate variable on the human-machine interface (HMI) for real-time monitoring by process operators.

[0020] Furthermore, in step eight, the following signal points are added to the high-speed data acquisition system IBA: 10-second power-off delay at the falling edge of the pre-rough rolling hot inspection signal, falling edge of the pre-rough rolling hot inspection signal, red-hot steel signal at the pre-rough rolling hot inspection, time between the head and tail of the steel on the furnace exit roller table <= 7 seconds, and small gap time of the steel exiting rhythm and the steel separation roller table. This facilitates real-time tracking of the working condition of small gap time of the steel exiting rhythm and the ability to query historical data tracking signals, so as to improve and optimize the control of this interlock.

[0021] Furthermore, the high-speed data acquisition system IBA can simultaneously record 1024 analog + 1024 digital channels of signals within 1ms. It can be gradually expanded in units of 8 channels to achieve high-speed data acquisition, recording and analysis of production process data, and can be directly connected to most PLC control systems.

[0022] Beneficial effects

[0023] Compared with the prior art, the advantages of this invention are as follows:

[0024] This invention detects red-hot steel signals from the hot metal detector before roughing rolling, the falling edge of the hot metal detector signal before roughing rolling, a 10-second power-off delay after the falling edge of the hot metal detector signal before roughing rolling, tracking the steel tapping rhythm setting data, the interval between the head and tail of the steel tapping rollers, the real-time value of the interval between the head and tail of the steel tapping rollers, the data tracking of the interval between the head and tail of the steel tapping rollers being less than or equal to 7 seconds, alarm information for fast steel tapping rhythm and small gap time of the steel separating rollers, and dynamic energy flow acquisition signals of high-speed data acquisition signals; at the same time, it establishes a yellow text warning prompt in the control screen WINCC of the human-machine interface (HMI) for fast steel tapping rhythm and small gap time of the steel separating rollers. This prompt promptly reminds the operators to discover the red-hot steel tapping rhythm and the red-hot steel tracking position on site, so as to adjust and improve the steel tapping rhythm in time, and quickly increase the gap of the red-hot steel before the steel separating rollers to avoid the occurrence of red-hot steel collision accidents. This invention can improve rolling performance, perfect rolling rhythm, stabilize the red steel gap time of the steel separating roller, meet production rhythm, ensure yield, and avoid red steel collision accidents and equipment safety hazards of varying degrees in the steel separating system. Attached Figure Description

[0025] Figure 1 This is a flowchart of the present invention. Detailed Implementation

[0026] The present invention will be further described below with reference to specific embodiments shown in the accompanying drawings.

[0027] See Figure 1 A control method for avoiding rear-end collisions involving red-hot steel, characterized by comprising the following steps one through eight:

[0028] Step 1. Acquire the rising edge signal of red steel from the hot metal detector before rough rolling of the next steel.

[0029] In the PLC control system of the double high-speed rolling mill, a rising edge signal pulse program system for the hot metal detector before roughing is established to detect the presence of red steel. According to the production process, after the red steel is heated in the heating furnace, the rolling line control system sends an automatic steel demand signal. The red steel enters the exit roller table through the continuously running exit cantilever roller of the heating furnace. When the head of the red steel passes through the hot metal detector before roughing, the hot metal detector immediately collects the presence of steel at the head of the red steel and generates a steel presence signal, which is fed back to the digital input module of the PLC control system. This provides the PLC control system with the rising edge signal of the hot metal detector before roughing, and assigns this rising edge signal to the intermediate variable in the program.

[0030] Digital input / output (DI / DO) modules are used to receive and output digital signals from the field to field devices. DI modules receive various switching statuses from electrical circuits, such as the status of motor or contactor contacts, or the status of valve limit switches. DO modules control the start and stop of field solenoid valves or motors.

[0031] Step 2. Acquire the falling edge signal of the hot metal detector before rough rolling of the upper red steel.

[0032] In the PLC1 control system of the double high-speed rolling mill, a falling edge signal pulse program system is established for the hot metal detector before roughing to detect the presence of red steel. According to the production process, after the red steel is heated in the heating furnace, the rolling line control system sends an automatic steel demand signal. The red steel enters the furnace exit roller table through the continuously running furnace exit cantilever roller. When the tail of the red steel passes the hot metal detector before roughing, the hot metal detector immediately detects the absence of steel at the tail of the red steel and feeds back to the digital input module of the PLC control system. This provides the PLC control system with the falling edge pulse of the hot metal detector signal before roughing, and assigns this falling edge signal to the intermediate variable in the program as the interlock control condition for the next step.

[0033] Hot metal detectors can operate stably and reliably in harsh environments.

[0034] Step 3. Collect the falling edge of the hot inspection signal before rough rolling of the upper steel and the 10-second power-off delay interlock signal.

[0035] Based on the double-high wire rod rolling condition, according to step two, the falling edge signal of the hot metal detector before rough rolling of the upper red steel is used as the pulse trigger condition for the tail of the upper red steel to pass through the hot metal detector before rough rolling. Using the power-off delay function of the power-off delay timer S_OFFDT in the PLC control system, according to the control requirements of the on-site process production conditions and rolling rhythm, if the falling edge of the detection signal of the tail of the upper steel passes through the hot metal detector before rough rolling arrives, the power-off delay timer S_OFFDT set in the program is set to a 10-second delay power-off, and the output result is stored in an intermediate variable register as a prerequisite for subsequent interlocking control.

[0036] The power-off delay timer S_OFFDT is used to disconnect the output only after a certain delay when the input is disconnected. When the enable input IN is valid, the timer output status bit is immediately set to 1, and the current value is reset to 0. When the enable input IN is disconnected, the timer starts counting, and the current value increments from 0. When the current value reaches the preset value, the timer status bit is reset to 0, and the counting stops, while the current value is retained.

[0037] Step 4. Establish the actual jump value of the time component when the upper steel tail rolls out of the roughing mill 2 stands.

[0038] According to the production process, there are frequent shutdowns for maintenance on-site. During these shutdowns, the hot-rolled steel needs to remain in the heating furnace for heat preservation. After the previous hot-rolled steel is rolled into the roughing mill and then ejected, the subsequent hot-rolled steel will remain in the heating furnace for a long time. Therefore, the time interval between the head and tail of the two hot-rolled steel sections needs to be appropriately managed. Using the steel presence signal of the second roughing mill stand as a reference, the ejection signal of the hot-rolled steel in the second roughing mill stand is collected. Under the condition that all mills are operating normally, the FC20 delay time function block inside the PLC control system is used to set the pre-set time to 500 seconds. This time is the pre-set time for the hot-rolled steel in the second roughing mill stand to be ejected under the condition that all mills are operating. Simultaneously, the real-time time value after the ejection of the steel in the second roughing mill stand is recorded in the FC20 delay time function block and stored in the double-word variable point in the DB block. This is used as the time interval parameter between the head and tail of the two hot-rolled steel sections to establish the actual jump value of the time component when the tail of the previous steel section passes through the second roughing mill stand.

[0039] The FC20 delay time function block is a general-purpose delay time function block that is programmed in the PLC software control program using statement list programming. It consists of enable terminals, input start terminals, time preset terminals, real-time variable value jump terminals, and enable output terminals. These function terminals and control terminal components are then compiled into a single block for use by the actual control program.

[0040] Step 5. Establish the actual value of the time component when the head of the next steel bar is rolled into the second stand of the roughing mill and assign values ​​for comparison.

[0041] Based on the actual jump value of the time component when the tail of the upper steel bar exits the second roughing stand in step four, the actual time jump value when the upper red steel bar exits the second roughing stand is obtained. It is also necessary to establish the actual value of the time component when the head of the lower red steel bar enters the second roughing stand, so as to obtain the actual time gap value between the tail of the upper red steel bar and the head of the lower red steel bar.

[0042] First, the presence of steel signal generated by the rolling of red-hot steel in the two roughing stands is collected. This presence of steel signal generates a pulse variable and simultaneously triggers the preset time of the FC20 delay time function block in step four. This preset time is assigned to a DB variable point, which is defined as the time interval between the beginning and end of the two red-hot steel sections. Using this time interval as a reference, if the time interval between the beginning and end of the two red-hot steel sections is greater than or equal to 100 seconds, the time interval between the beginning and end of the two red-hot steel sections will be determined to be 100 seconds. If the time interval between the beginning and end of the two red-hot steel sections exceeds 100 seconds during normal rolling, it indicates that there is a temporary stoppage for maintenance or a change from double-high-speed wire rod rolling to single-wire rolling.

[0043] Step 6. Track data on the time gap between the two red steel ends being less than or equal to 7 seconds and generate intermediate numerical variables.

[0044] According to the process production requirements, based on the actual value of the time component established in step five when the head of the next steel bar is rolled into the second roughing mill stand, and after comparison, the pre-set time of the FC20 delay time function block is collected in the PLC control system. The steel signal generated by the rolling of the red steel in the second roughing mill stand is also collected. This steel signal generates a pulse variable, which simultaneously triggers the pre-set time of the FC20 delay time function block in step four. This pre-set time is assigned to a DB variable point, which is defined as the time gap between the head and tail of the two red steel bars. Using this time gap as a reference, if the time gap between the head and tail of the two red steel bars is less than or equal to 7 seconds, the interlocking control condition of the time gap between the head and tail of the two red steel bars being less than or equal to 7 seconds is output to an intermediate variable control point as the premise and basis for subsequent interlocking control.

[0045] The preset time of the FC20 delay time function block is converted into data using a PLC control system. Since the preset time variable DB point of the FC20 delay time function block is in double-digit format, it needs to be converted to a real number by the program. Because on-site operators are accustomed to viewing time in seconds, while the original preset time variable DB point of the FC20 delay time function block is displayed in milliseconds in the program, it needs to be displayed in seconds. Dividing the real-type preset time variable DB point by 1000 yields the preset time in seconds. Finally, the preset time of the two red steel head and tail time intervals, displayed in seconds as a real-type variable, is displayed as an intermediate variable on the HMI for real-time monitoring by the process operators.

[0046] A real number whose value can be changed during program execution is called a real variable. Real variables are divided into single-precision (float), double-precision (double), and long double-precision (long double) types.

[0047] Step 7. Correspond to the control output of fast steel output rhythm and small gap time between steel rollers to avoid red steel tailing.

[0048] Based on the process requirements and combining steps one through six above, we obtain the first interlocking control program condition and the second series interlocking control program condition. The first interlocking control program condition is: during the 10-second power-off delay timer of the falling edge of the hot metal detector signal before the roughing of the upper steel bar. The second series interlocking control program condition is: if the hot metal detector before the roughing of the lower steel bar detects a rising edge signal of red steel, and during the 10-second power-off delay timer in the first interlocking control program condition, a rising edge signal of red steel is detected when the hot metal detector before the roughing of the lower steel bar enters the mill, this indicates a high steel output rhythm and a small gap between the steel conveyor rollers, potentially leading to a red steel bar collision. In this case, a signal indicating a high steel output rhythm and a small gap between the steel conveyor rollers is output, indicating a risk of red steel bar collision.

[0049] By combining step six with data tracking of the time gap between the two red steel heads and tails being less than or equal to 7 seconds and forming an intermediate numerical variable, if the time gap between the two red steel heads and tails is less than or equal to 7 seconds, a signal is also output indicating that the steel rhythm is fast and the gap time between the steel rollers is small, which may lead to the risk of red steel rear-end collision. This achieves a double avoidance of red steel rear-end collision accidents.

[0050] Step 8. Collect the output interlock signal of the fast steel output rhythm and the small gap time of the steel separation roller table to the screen alarm and high-speed data acquisition system.

[0051] The alarm section on the main screen of the WINCC human-machine interface displays a yellow text alarm reminder when the gap between the steel rollers in the fast steel rhythm is small, so as to promptly provide feedback to the process operators to control the production rhythm and avoid accidents caused by the head and tail of the red-hot steel.

[0052] Meanwhile, the following signal points are added to the high-speed data acquisition system IBA: 10-second power-off delay when the hot inspection signal falls before roughing, the falling edge of the hot inspection signal before roughing, the presence of red steel signal during the hot inspection before roughing, the time between the head and tail of the steel on the furnace exit roller table <= 7 seconds, and the small gap time of the steel exiting rhythm roller table. This facilitates real-time tracking of the working condition of small gap time of the steel exiting rhythm roller table. Historical data tracking signals can also be queried to improve and optimize the interlocking control.

[0053] The high-speed data acquisition system IBA can simultaneously record 1024 analog + 1024 digital channels of signals within 1ms. It can be gradually expanded in units of 8 channels to achieve high-speed (1ms) data acquisition, recording and analysis of production process data, and can be directly connected to most PLC control systems.

[0054] The above are merely preferred embodiments of the present invention. It should be noted that those skilled in the art can make several modifications and improvements without departing from the structure of the present invention, and these will not affect the effectiveness of the implementation of the present invention or the practicality of the patent.

Claims

1. A control method for avoiding rear-end collisions with red-hot steel, characterized in that, Includes the following steps: Step 1. Collect the rising edge signal of the hot metal detector before roughing the next red steel. Establish a pulse program system for the rising edge signal of the hot metal detector before roughing the red steel in the double high-speed line PLC control system. According to the production process, after the red steel is heated in the heating furnace, the rolling line control system sends an automatic hot steel demand signal. The red steel enters the furnace exit roller table through the continuously running furnace exit cantilever roller. When the head of the red steel passes the hot metal detector before roughing the steel, the hot metal detector immediately collects the red steel head and generates a red steel signal, and feeds it back to the digital input module of the double high-speed line PLC control system. This provides the double high-speed line PLC control system with the rising edge signal of the hot metal detector before roughing the steel, and assigns this rising edge signal to the intermediate variable in the program of the double high-speed line PLC control system. Step 2. Acquire the falling edge signal of the hot metal detector before roughing the upper red steel. Establish a pulse program system for the falling edge signal of the hot metal detector before roughing the upper red steel in the double high-speed line PLC control system. According to the production process, after the red steel is heated in the heating furnace, the rolling line control system sends an automatic red steel demand signal. The red steel enters the furnace exit roller table through the continuously running furnace exit cantilever roller. When the tail of the red steel passes the hot metal detector before roughing the upper red steel, the hot metal detector immediately removes the red steel signal generated at the tail of the red steel and feeds it back to the digital input module of the double high-speed line PLC control system. This provides the double high-speed line PLC control system with the falling edge signal of the hot metal detector before roughing the upper red steel and assigns this falling edge signal to the intermediate variable in the program of the double high-speed line PLC control system as the interlock control condition for the next step. Step 3. Acquire the falling edge signal of the hot metal detector before roughing of the upper red steel and the 10-second power-off delay interlock signal. Based on the double high-speed wire rod rolling condition, according to the falling edge signal of the hot metal detector before roughing of the upper red steel collected in Step 2, the pulse trigger condition for the tail of the upper red steel to be detected by the hot metal detector before roughing is used. Utilize the power-off delay function of the power-off delay timer S_OFFDT in the double high-speed wire rod PLC control system. According to the control requirements of the on-site process production conditions and rolling rhythm, if the falling edge signal of the hot metal detector before roughing of the upper red steel arrives, set the power-off delay timer S_OFFDT set in the program of the double high-speed wire rod PLC control system to a 10-second delay power-off, and store the output result in an intermediate variable register as a prerequisite for subsequent interlock control. Step 4. Establish the actual jump value of the time component when the tail of the upper red steel is rolled out of the second roughing mill stand. According to the process production conditions, there are often rolling stoppages for maintenance on site. At this time, the red steel needs to stay in the heating furnace for heat preservation treatment. After the upper red steel is rolled into the roughing mill and then ejected, the subsequent red steel will stay in the heating furnace for a long time. At this time, the time interval between the head and tail of the two red steels needs to be properly handled. Taking the red steel signal of the second roughing mill stand as the reference, collect the ejection signal of the red steel rolled into the second roughing mill stand. Under the condition that all mills are operating normally, use the double high The FC20 delay time function block inside the line PLC control system is set to a preset time of 500 seconds. This time is the preset time when the red steel rolled into the roughing mill 2 stands is thrown out under all rolling mill operating conditions. At the same time, the real-time time value after the steel is thrown out by the roughing mill 2 stands is recorded in the FC20 delay time function block and stored in the double-word variable point in the DB block. This is used as the gap time parameter between the head and tail of the two red steel bars to establish the actual jump value of the time component when the tail of the upper red steel bar passes through the roughing mill 2 stands. Step 5. Establish and compare the actual value of the time component when the head of the lower red steel is rolled into the second roughing mill stand. Based on the actual jump value of the time component when the tail of the upper red steel is rolled out of the second roughing mill stand in Step 4, obtain the actual time jump value when the upper red steel is rolled out of the second roughing mill stand. It is also necessary to establish the actual value of the time component when the head of the lower red steel is rolled into the second roughing mill stand, so as to obtain the actual time gap value between the tail of the upper red steel and the head of the lower red steel. Step Six. Track data on the time gap between the two red steel heads and tails being less than or equal to 7 seconds and form an intermediate numerical variable. According to the process production requirements, compare the actual value of the time component established in Step Five when the head of the next red steel is rolled into the second stand of the roughing mill. In the dual-high-speed PLC control system, collect the pre-set time of the FC20 delay time function block and collect the red steel signal generated by the rolling of red steel into the second stand of the roughing mill. This red steel signal generates a pulse variable and triggers the pre-set time of the FC20 delay time function block in Step Four. Assign this pre-set time to a DB variable point and define this DB variable point as the time gap between the two red steel heads and tails. Use this time gap as a reference. If the time gap between the two red steel heads and tails is less than or equal to 7 seconds, output the interlocking control condition of the time gap between the two red steel heads and tails being less than or equal to 7 seconds to an intermediate variable control point as the premise and basis for subsequent interlocking control. Step 7. Corresponding to the control output of fast steel tapping rhythm and small gap time between steel conveyors to avoid red-hot steel collision, based on the process production requirements and combined with Steps 1 to 6 above, we obtain the first interlocking control program condition and the second series interlocking control program condition. The first interlocking control program condition is: A falling edge signal from the hot metal detector before the roughing of the previous red-hot steel indicates a 10-second power-off delay during the 10-second power-off delay. The second series interlocking control program condition is: A rising edge signal from the hot metal detector before the roughing of the next red-hot steel indicates a red-hot steel collision. If, during the 10-second power-off delay in the first interlocking control program condition, the hot metal detector detects a rising edge signal before the roughing of the next red-hot steel, it indicates a risk of red-hot steel collision due to the fast steel tapping rhythm and small gap time between steel conveyors. At this time, the signal indicating a fast steel tapping rhythm and small gap time between steel conveyors is output to mitigate the risk of red-hot steel collision. Combined with step six, data tracking is performed on the time gap between the two red steel heads and tails being less than or equal to 7 seconds, and intermediate numerical variables are formed. If the time gap between the two red steel heads and tails is less than or equal to 7 seconds, a signal is also output indicating that the steel rhythm is fast and the gap time between the steel rollers is small, which may lead to the risk of red steel rear-end collision. This achieves a double avoidance of red steel rear-end collision accidents. Step 8. Collect the output interlock signal of the fast steel separation roller conveyor with small gap time associated with the steel output rhythm to the screen alarm and high-speed data acquisition system. In the alarm column of the main screen of the human-machine interface WINCC screen, display the screen alarm reminder of small gap time of the fast steel separation roller conveyor with yellow text, so as to promptly provide feedback to the process operators to control the production rhythm and avoid the accident of the head and tail of the red steel.

2. The control method for avoiding rear-end collisions with red-hot steel according to claim 1, characterized in that, In step one, the digital input module is a DI / DO module, which is used to receive switch signals from the field or output switch signals to the field devices; the DI module is used to receive various switch states from the electrical circuit, and the DO module is used to control the start and stop of the field solenoid valve or motor.

3. The control method for avoiding rear-end collisions with red-hot steel according to claim 1, characterized in that, In step three, the power-off delay timer S_OFFDT is used to disconnect the output only after a certain delay when the input is disconnected. When the enable input (IN) is valid, the timer output status bit is immediately set to 1, and the current value is reset to 0. When the enable input (IN) is disconnected, the timer starts counting, and the current value increments from 0. When the current value reaches the preset value, the timer status bit is reset to 0, and the counting stops, while the current value is retained.

4. The control method for avoiding rear-end collisions with red-hot steel according to claim 1, characterized in that, In step four, the FC20 delay time function block is created in the program of the dual-high-line PLC control system by programming the enable terminal, input start terminal, time preset terminal, real-time variable value jump terminal and enable output terminal in the statement list method, and these function terminals and control terminal components are compiled into a general delay time function block.

5. The control method for avoiding rear-end collisions with red-hot steel according to claim 1, characterized in that, In step five, the red steel signal generated by the rolling of red steel in the two roughing stands is first collected. This red steel signal generates a pulse variable and simultaneously triggers the preset time of the FC20 delay time function block in step four. This preset time is assigned to a DB variable point, which is defined as the time gap between the head and tail of the two red steel bars. Using this time gap as a reference, if the time gap between the head and tail of the two red steel bars is greater than or equal to 100 seconds, the time gap between the head and tail of the two red steel bars will be determined to be 100 seconds. If the time gap between the head and tail of the two red steel bars exceeds 100 seconds during normal rolling, it indicates that there is a temporary stop for rolling maintenance or a change from double-high wire rolling to single-wire rolling.

6. The control method for avoiding rear-end collisions with red-hot steel according to claim 1, characterized in that, In step six, the preset time of the FC20 delay time function block is converted into data using the dual-high-line PLC control system. The preset time variable DB point of the FC20 delay time function block is converted into a real number by the program of the dual-high-line PLC control system, and the preset time variable DB point of the FC20 delay time function block is expressed in the form of time seconds. Finally, the preset time of the time gap between the two red steel heads and tails, expressed in seconds, is displayed as an intermediate variable on the human-machine interface (HMI) for real-time monitoring by process operators.

7. The control method for avoiding rear-end collisions with red-hot steel according to claim 1, characterized in that, In step eight, the following signal points are added to the high-speed data acquisition system IBA: a 10-second power-off delay for the falling edge signal of red steel detected by the hot metal detector before roughing, a falling edge signal of red steel detected by the hot metal detector before roughing, a red steel signal detected by the hot metal detector before roughing, a time between the head and tail of steel on the tapping roller conveyor ≤ 7 seconds, and a small gap time on the fast tapping rhythm steel separating roller conveyor. This facilitates real-time tracking of the working condition of a fast tapping rhythm steel separating roller conveyor with a small gap time. Historical data tracking signals can also be queried to improve and optimize the interlocking control.

8. The control method for avoiding rear-end collisions with red-hot steel according to claim 7, characterized in that, The high-speed data acquisition system IBA can simultaneously record 1024 analog + 1024 digital channels of signals within 1ms. It can be gradually expanded in units of 8 channels to achieve high-speed data acquisition, recording and analysis of production process data, and can be directly connected to most dual-high-speed PLC control systems.

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