Automatic speed increasing and decreasing control system and method for rolling mill
By designing an automatic lifting and lowering control system for rolling mills including inverters, alternating motors, PLC modules, WINCC modules and external sensors, the problems of low production efficiency and prone to rear-end collisions in the existing high-speed wire rolling mills are solved, and the automatic speed regulation and production efficiency of rolling mills are improved.
Patent Information
- Application Number
- CN202411749910.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-02
- Publication Date
- 2025-03-11
AI Technical Summary
In the existing high-speed wire rolling mill main control system, the rolling mill speed control only has the manual lifting and lowering function, which leads to the possibility of rear-end steel rear-end steel accidents and low production efficiency when rolling high-speed continuous rolling mills.
Design a rolling mill automatic lifting and lowering control system, including inverter, alternating current motor, PLC module, WINCC module and external sensor, and control the inverter and alternating current motor through the PLC module to realize automatic speed regulation of the rolling mill. The system uses a metal detector to detect the moment the rod tail is separated, calculates the distance between the rolling mill and the detector, and automatically controls the rolling mill to avoid rear-end collisions.
The automatic speed adjustment of the rolling mill is achieved, manual intervention is reduced, production efficiency is improved, steel flushing accidents are avoided, and the orderly, efficient and safe rolling of the bars is ensured.
Smart Images
Figure CN119588755A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of rolling technology, and in particular to a rolling mill automatic speed increase and decrease control system and method. Background Art
[0002] At present, all steel and metallurgical enterprises are equipped with continuous casting production lines. Continuous casting of steel is an essential part of modern steel and metallurgical technology. The continuous casting ratio represents the advanced level of steel and metallurgical technology. Continuous casting machines are used to produce billets such as round billets, square billets, and slabs for rolling mills.
[0003] Direct rolling of hot billet from continuous casting is a newly developed smelting-rolling process, that is, the billet from continuous casting is not rolled through a secondary heating rolling mill. At present, six varieties of products have been successfully developed, including flanges for pipe piles, high-speed PC rods and wires for pipe piles, and 45# steel wires. The production process adopted is: steel material → electric arc furnace → refining furnace → continuous casting → sizing → rough rolling → medium rolling → finishing rolling → water cooling → wire laying → air cooling → coiling → inspection → packaging → weighing and hanging → coil unloading → storage.
[0004] At present, the main control system of the high-speed wire rod mill adopts Siemens. The existing rolling mill speed control in the main control system only has the manual speed increase and decrease function. In the actual production process, when the front and rear two steels are rolled on the high-speed continuous rolling mill at the same time, if the rear steel is too close to the tail of the front steel due to the speed difference of the rolling mill, the ground operator will notify the main control room to manually adjust the speed to avoid the front and rear steels from rear-ending and causing steel collision accidents. Since the speed adjustment range is mainly determined based on human visual judgment, manual operation is required throughout the process, and there are many cases of misjudgment. The high-speed wire rod mill rolling speed increase (decrease) is different due to different personal experience and different adjustment time. Fear of accidents directly leads to the continuous casting of only 4 streams, which seriously affects the normal operation of the smelting process and low operating efficiency. Summary of the invention
[0005] The object of the present invention is to provide a rolling mill automatic speed increase and decrease control system and method, aiming to solve the problem of low production efficiency of existing high-speed wire rolling.
[0006] To achieve the above-mentioned object, in a first aspect, the present invention provides a rolling mill automatic speed control system, comprising an inverter, an AC motor, a PLC module, a WINCC module and an external sensor, wherein the PLC module is connected to the WINCC module and the external sensor respectively, and the inverter is connected to the AC motor;
[0007] The inverter is used to control the action of the AC motor;
[0008] The AC motor is used to control the operation of the rolling mill;
[0009] The PLC module is used to control the inverter operation;
[0010] The WINCC module is used to realize visualization and operation control of the equipment;
[0011] The external sensor collects external IO signals based on the control of the PLC module.
[0012] Wherein, the PLC modules are Siemens CU320 and S7-1500 PLC.
[0013] In a second aspect, the present invention further provides a rolling mill automatic speed increase and decrease control method, which is applied to a rolling mill automatic speed increase and decrease control system described in the first aspect, and is characterized in that it comprises the following steps:
[0014] Set the speed reduction parameters and install the rolling system;
[0015] The metal detector of the rolling system detects the moment when the tail of the bar is separated, calculates the distance between the first rolling mill and the metal detector, and obtains the running distance;
[0016] The bar runs the running distance after leaving the hot metal detector. If the hot metal detector does not detect a new bar, the first rolling mill is not controlled to slow down. If the hot metal detector detects a new bar, the first rolling mill is controlled to slow down.
[0017] Wherein, the rolling system includes a hot metal detector, a first rolling mill, a second rolling mill, a third rolling mill, a fourth rolling mill, a fifth rolling mill and a sixth rolling mill, the first rolling mill is arranged on a side of the hot metal detector, the second rolling mill is arranged on a side of the first rolling mill away from the hot metal detector, the third rolling mill is arranged on a side of the second rolling mill away from the first rolling mill, the fourth rolling mill is arranged on a side of the third rolling mill away from the second rolling mill, the fifth rolling mill is arranged on a side of the fourth rolling mill away from the third rolling mill, and the sixth rolling mill is arranged on a side of the fifth rolling mill away from the fourth rolling mill.
[0018] Among them, the speed reduction parameters include the distance from the front roller heat inspection to the first rolling mill, the delayed speed reduction time setting, the remaining starting speed reduction distance, the speed reduction coefficient setting of the first rolling mill and the speed reduction protection limit time.
[0019] The metal detector of the rolling system detects the moment when the tail of the bar is separated, calculates the distance between the first rolling mill and the metal detector, and obtains the specific method of the running distance:
[0020] The metal detector of the rolling system detects the moment when the tail of the bar is separated;
[0021] Based on the separation moment, the integral of the speed of the first rolling mill over time is calculated, and the distance between the first rolling mill and the metal detector is calculated to obtain the running distance.
[0022] The formula for calculating the distance between the first rolling mill and the metal detector is: s=∫v(t)dt, wherein ∫ represents the integral symbol, t represents time, and v(t) represents the speed of the object at time t.
[0023] The present invention discloses a rolling mill automatic speed control system, wherein the inverter is used to control the action of the AC motor; the AC motor is used to control the operation of the rolling mill; the PLC module is used to control the action of the inverter; the WINCC module is used to realize visualization and operation control of the equipment; the external sensor controls and collects external IO signals based on the PLC module. Specifically, the WINCC module is connected to the PLC module through PROFINET to realize visualization and operation control of the equipment. Among them, the CU320 of the PLC module is connected to the S7-1500PLC through PROFINET to realize information exchange between the S7-1500PLC and the CU320. The PLC module is connected to the inverter through PROFINET to realize motion control of the S120 inverter by CU320. The inverter is connected to the AC motor through a power cable to realize the inverter to control the operation of the AC motor. The AC motor is connected to the rolling mill through a coupling to realize the operation control of the rolling mill. The PLC module is connected to the external sensor to realize the collection of external IO signals. The system is equipped with self-developed program logic through the PLC module, realizes human-computer interaction through the WINCC module, and realizes automatic speed reduction through the speed reduction coefficient set on the WINCC module screen. Without manual participation, it automatically detects and calculates the start speed reduction time of the first rolling mill, and restores the speed reduction conditions, so that the bars are rolled on the production line in an orderly, efficient and safe manner. A speed reduction time protection is set to force the normal speed to be restored when the protection time is reached, thereby preventing the bars from being broken due to external signal errors, and solving the problem of low production efficiency of existing high-speed wire rolling. BRIEF DESCRIPTION OF THE DRAWINGS
[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0025] Figure 1 It is a connection schematic diagram of a rolling mill automatic speed increase and decrease control system provided by the present invention.
[0026] Figure 2 It is the equipment schematic diagram of the rolling system.
[0027] Figure 3 The present invention provides a flow chart of a rolling mill automatic speed increase and decrease control method.
[0028] Figure 4 It is the first rolling mill speed reduction parameter setting and monitoring diagram.
[0029] Figure 5 It is the first rolling mill speed reduction parameter setting and monitoring diagram.
[0030] Figure 6 It is the first rolling mill speed reduction parameter setting and monitoring diagram.
[0031] Figure 7 This is the speed reduction curve of the first rolling mill.
[0032] Figure 8 It is a schematic diagram of the steps of a rolling mill automatic speed increase and decrease control method provided by the present invention.
[0033] In the figure: 1-hot metal detector, 2-first rolling mill, 3-second rolling mill, 4-third rolling mill, 5-fourth rolling mill, 6-fifth rolling mill, 7-sixth rolling mill, 8-bar, 9-WINCC module, 10-PLC module, 11-external sensor, 12-inverter, 13-AC motor. DETAILED DESCRIPTION
[0034] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.
[0035] See also Figures 1 to 5 In a first aspect, the present invention provides a rolling mill automatic speed control system, comprising an inverter 12, an AC motor 13, a PLC module 10, a WINCC module 9 and an external sensor 11, wherein the PLC module 10 is connected to the WINCC module 9 and the external sensor 11 respectively, and the inverter 12 is connected to the AC motor 13;
[0036] The inverter 12 is used to control the operation of the AC motor 13;
[0037] The AC motor 13 is used to control the operation of the rolling mill;
[0038] The PLC module 10 is used to control the operation of the inverter 12;
[0039] The WINCC module 9 is used to realize visualization and operation control of the equipment;
[0040] The external sensor 11 collects external IO signals based on the control of the PLC module 10 .
[0041] In the embodiment of the present invention, the inverter 12 is used to control the action of the AC motor 13; the AC motor 13 is used to control the operation of the rolling mill; the PLC module 10 is used to control the action of the inverter 12; the WINCC module 9 is used to realize visualization and operation control of the equipment; the external sensor 11 controls and collects external IO signals based on the PLC module 10. Specifically, the WINCC module 9 is connected to the PLC module 10 through PROFINET to realize visualization and operation control of the equipment. Among them, the CU320 of the PLC module 10 is connected to the S7-1500PLC through PROFINET, so that the S7-1500PLC can exchange information with the CU320. The PLC module 10 is connected to the inverter 12 through PROFINET, so that the CU320 can control the motion of the S120 inverter 12. The inverter 12 is connected to the AC motor 13 through a power cable, so that the inverter 12 can control the operation of the AC motor 13. The AC motor 13 is connected to the rolling mill through a coupling to realize the operation control of the rolling mill. The PLC module 10 is connected to the external sensor 11 to realize the acquisition of external IO signals. The system is equipped with self-developed program logic through the PLC module 10, realizes human-computer interaction through the WINCC module 9, and realizes automatic speed reduction through the speed reduction coefficient set on the WINCC module 9 screen. Without manual participation, it automatically detects and calculates the start speed reduction time of the first rolling mill, restores the speed reduction conditions, and makes the bars roll on the production line in an orderly, efficient and safe manner. A speed reduction time protection is set to force the normal speed to be restored when the protection time is reached, to prevent the bars from being broken due to external signal errors, and to solve the problem of low production efficiency of existing high-speed wire rolling.
[0042] In a second aspect, the present invention further provides a rolling mill automatic speed increase and decrease control method, which is applied to a rolling mill automatic speed increase and decrease control system described in the first aspect, and is characterized in that it comprises the following steps:
[0043] S1 sets the speed reduction parameters and installs the rolling system;
[0044] In an embodiment of the present invention, the speed reduction parameters include the distance (m) from the front roller thermal inspection to the first rolling mill 2, the delayed speed reduction time setting (ms), the remaining starting speed reduction distance (m), the speed reduction coefficient setting of the first rolling mill 2 (%) and the speed reduction protection limit time (s).
[0045] The rolling system includes a hot metal detector 1, a first rolling mill 2, a second rolling mill 3, a third rolling mill 4, a fourth rolling mill 5, a fifth rolling mill 6 and a sixth rolling mill 7. The first rolling mill 2 is arranged on one side of the hot metal detector 1, the second rolling mill 3 is arranged on one side of the first rolling mill 2 away from the hot metal detector 1, the third rolling mill 4 is arranged on one side of the second rolling mill 3 away from the first rolling mill 2, the fourth rolling mill 5 is arranged on one side of the third rolling mill 4 away from the second rolling mill 3, the fifth rolling mill 6 is arranged on one side of the fourth rolling mill 5 away from the third rolling mill 4, and the sixth rolling mill 7 is arranged on one side of the fifth rolling mill 6 away from the fourth rolling mill 5.
[0046] Specifically, the hot metal detector 1 is used to detect the bars fed into the first rolling mill, and the first rolling mill 2, the second rolling mill 3, the third rolling mill 4, the fourth rolling mill 5, the fifth rolling mill 6 and the sixth rolling mill 7 are respectively responsible for the rolling of the steel bars.
[0047] S2: the metal detector of the rolling system detects the moment when the tail of the bar 8 is separated, calculates the distance between the first rolling mill 2 and the metal detector, and obtains the running distance;
[0048] In the embodiment of the present invention, the metal detector of the rolling system detects the moment when the tail of the bar 8 is separated, calculates the distance between the first rolling mill 2 and the metal detector, and obtains the specific method of the running distance:
[0049] S21: the metal detector of the rolling system detects the moment when the tail of the bar 8 is separated;
[0050] S22 calculates the integral of the speed of the first rolling mill 2 over time based on the separation moment, calculates the distance between the first rolling mill 2 and the metal detector, and obtains the running distance.
[0051] In an embodiment of the present invention, the formula for calculating the running distance (i.e., the value of "remaining starting deceleration distance" is reduced to 0) is: s=∫v(t)dt, wherein ∫ represents the integral sign, t represents time, and v(t) represents the speed of the object at time t.
[0052] S3: the bar 8 runs the running distance after leaving the hot metal detector 1. If the hot metal detector 1 does not detect a new bar 8, the first rolling mill 2 is not controlled to slow down. If the hot metal detector 1 detects a new bar 8, the first rolling mill 2 is controlled to slow down.
[0053] In the embodiment of the present invention, when the bar 8 leaves the hot metal detector 1 and runs the distance between the hot metal detector 1 and the first rolling mill 2 (that is, the "remaining starting speed reduction distance" value is reduced to 0), and the hot metal detector 1 has not detected the bar 8 (there is no bar 8 rear-ending), the first rolling mill 2 does not slow down.
[0054] If the tail of the previous bar 8 leaves the hot metal detector 1 and has not yet traveled the distance between the hot metal detector 1 and the first rolling mill 2, and the hot metal detector 1 detects a bar 8 again, it means that the next billet is too close and rear-ends, and the "rear-end calculation" is started at this time. Figure 5 .
[0055] After calculating that the tail of the previous bar 8 has traveled the distance between the hot metal detector 1 and the first rolling mill 2 (i.e., the value of "remaining starting speed reduction distance" is reduced to 0), the first rolling mill 2 starts to reduce speed according to the set "speed reduction coefficient setting" parameter (the current set speed reduction coefficient is 0.7, i.e., 70%). Figure 6 .
[0056] The speed of the first rolling mill 2 is reduced from the set 1052r / min to 736r / min. Figure 7 The first rolling mill 2 is decelerated until the preceding bar 8 is separated from the second rolling mill 3, and then the speed of the first rolling mill 2 is restored, thereby increasing the distance between the two trailing bars 8.
[0057] In order to prevent the speed reduction coefficient from being set too small, which will cause the distance between the front and rear bars 8 to be unable to be pulled apart, the second rolling mill 3 always has current for the bars 8, and thus cannot identify whether the previous bar 8 has left the second rolling mill 3, causing the first rolling mill 2 to continue to reduce speed and break the bar 8. A special "speed reduction protection limit time (s)" is set. After the first rolling mill 2 reduces speed to this time, it is forced to restore the speed of the first rolling mill 2 to avoid the bar 8 being broken.
[0058] The above disclosure is only a preferred embodiment of a rolling mill automatic speed control system and method of the present invention. Of course, this cannot be used to limit the scope of rights of the present invention. Ordinary technicians in this field can understand that all or part of the processes of the above embodiments and equivalent changes made according to the claims of the present invention still fall within the scope of the invention.
Claims
1. A rolling mill automatic speed control system, characterized in that: It includes an inverter, an AC motor, a PLC module, a WINCC module and an external sensor, wherein the PLC module is connected to the WINCC module and the external sensor respectively, and the inverter is connected to the AC motor; The inverter is used to control the action of the AC motor; The AC motor is used to control the operation of the rolling mill; The PLC module is used to control the inverter operation; The WINCC module is used to realize visualization and operation control of the equipment; The external sensor collects external IO signals based on the control of the PLC module.
2. A rolling mill automatic speed control system as claimed in claim 1, characterized in that: The PLC modules are Siemens CU320 and S120, and the PLC module is Siemens S7-1500 PLC.
3. A rolling mill automatic speed control method, applied to a rolling mill automatic speed control system as claimed in any one of claims 1-2, characterized in that: The following steps are involved: Set the speed reduction parameters and install the rolling system; The metal detector of the rolling system detects the moment when the tail of the bar is separated, calculates the distance between the first rolling mill and the metal detector, and obtains the running distance; The bar runs the running distance after leaving the hot metal detector. If the hot metal detector does not detect a new bar, the first rolling mill is not controlled to slow down. If the hot metal detector detects a new bar, the first rolling mill is controlled to slow down.
4. A rolling mill automatic speed control method as claimed in claim 3, characterized in that: The rolling system includes a hot metal detector, a first rolling mill, a second rolling mill, a third rolling mill, a fourth rolling mill, a fifth rolling mill and a sixth rolling mill. The first rolling mill is arranged on a side of the hot metal detector, the second rolling mill is arranged on a side of the first rolling mill away from the hot metal detector, the third rolling mill is arranged on a side of the second rolling mill away from the first rolling mill, the fourth rolling mill is arranged on a side of the third rolling mill away from the second rolling mill, the fifth rolling mill is arranged on a side of the fourth rolling mill away from the third rolling mill, and the sixth rolling mill is arranged on a side of the fifth rolling mill away from the fourth rolling mill.
5. A rolling mill automatic speed control method as claimed in claim 3, characterized in that: The speed reduction parameters include the distance from the front roller heat inspection to the first rolling mill, the delayed speed reduction time setting, the remaining starting speed reduction distance, the speed reduction coefficient setting of the first rolling mill and the speed reduction protection limit time.
6. A rolling mill automatic speed control method as claimed in claim 3, characterized in that: The metal detector of the rolling system detects the moment when the tail of the bar is separated, calculates the distance between the first rolling mill and the metal detector, and obtains the specific method of the running distance: The metal detector of the rolling system detects the moment when the tail of the bar is separated; Based on the separation moment, the integral of the speed of the first rolling mill over time is calculated, and the distance between the first rolling mill and the metal detector is calculated to obtain the running distance.
7. A rolling mill automatic speed control method as claimed in claim 6, characterized in that: The formula for calculating the distance between the first rolling mill and the metal detector is: s=∫v(t)dt, wherein ∫ represents the integral symbol, t represents time, and v(t) represents the speed of the object at time t.