Device and control method for automatically switching a rolling mill pressure head into a pressure sensor

Abstract

The present invention relates to a device and control method for automatically switching a mill platen into a pressure sensor, belonging to the technical field of rolling mill devices and control methods. The technical solution of the present invention is as follows: during the normal operation of the mill, steel rolling control is mainly carried out with the platen for rolling, and at the same time, the pressure sensor is used as a backup sensor; when an abnormal fault occurs to the platen during the rolling process, the rolling force detection of the mill realizes automatic switching to the pressure sensor for rolling, and at the same time, a platen alarm message is prompted on the human-machine interface; after the platen fault is processed, the pressure sensor is cancelled through the human-machine interface, and the original platen rolling state is restored. The beneficial effects of the present invention are: eliminating the influence of human factors and reducing the rolling line shutdown accidents caused by platen faults; when a fault occurs to the platen and an abnormality occurs in the detection, the system automatically switches to the pressure sensor for rolling, and then notifies the operator to check through an alarm, ensuring that the production line does not stop and avoiding the occurrence of steel piling accidents.

Description

Technical Field

[0001] The present invention relates to a control method for automatically switching a mill pressure head to a pressure sensor, and belongs to the technical field of steel rolling control methods. Background Art

[0002] In the metallurgical industry, there are many types of equipment on the hot-rolling steel production line, the control system structure is complex, and the control accuracy is high. As an important part of the steel rolling production line, ensuring the stable operation of the rolling mill is the primary goal of the steel rolling production line. At present, in order to ensure the stability of the rolling force detection of the rolling mill, a dual detection method of a pressure head and a pressure sensor is designed. The main reason is that after a failure occurs in the pressure head or the pressure sensor, the processing and replacement time is long, which affects the production efficiency. However, if a pressure head failure occurs on the production lines of major steel plants at present, it will inevitably cause the rolling line to stop for processing, and in severe cases, it will damage the equipment, cause secondary accidents, and increase the labor and material costs. At the same time, at present, manual selection is used for the pressure sensor to calibrate the rolling mill to ensure that the zero point of the pressure sensor is calibrated, and then it is put into use, which prolongs the downtime and reduces the steel rolling production efficiency. Summary of the Invention

[0003] The object of the present invention is to provide a control method for automatically switching a mill pressure head to a pressure sensor, which abandons the influence of human factors and reduces the rolling line shutdown accidents caused by pressure head failures; during the calibration process of the rolling mill, the pressure head and the pressure sensor are automatically calibrated to zero. When the pressure head fails and the detection is abnormal, the system automatically switches to the pressure sensor for rolling, and then notifies the operator to check through an alarm, ensuring that the production line does not stop and avoiding the occurrence of steel piling accidents, effectively solving the above problems existing in the background art.

[0004] The technical solution of the present invention is: a device for automatically switching a mill pressure head to a pressure sensor, characterized in that: it includes a pressure head and a pressure sensor. The pressure head includes a drive-side pressure head and an operation-side pressure head, and the drive-side pressure head and the operation-side pressure head are respectively installed below the drive side and the operation side of the lower support roll; the pressure sensor includes a drive-side rodless cavity pressure sensor, a drive-side rod cavity pressure sensor, an operation-side rodless cavity pressure sensor, and an operation-side rod cavity pressure sensor. The drive-side rodless cavity pressure sensor and the drive-side rod cavity pressure sensor are respectively installed on the hydraulic pipelines of the rod cavity and the rodless cavity of the drive-side hydraulic cylinder, and the operation-side rodless cavity pressure sensor and the operation-side rod cavity pressure sensor are respectively installed on the hydraulic pipelines of the rod cavity and the rodless cavity of the operation-side hydraulic cylinder.

[0005] A control method for automatically switching a mill pressure head to a pressure sensor includes the following steps:

[0006] (1) The driving side ram and the operating side ram are installed below the lower backup roll of the rolling mill to directly detect the rolling force. The pressure sensor for the rodless cavity on the driving side, the pressure sensor for the rod cavity on the driving side, the pressure sensor for the rodless cavity on the operating side, and the pressure sensor for the rod cavity on the operating side are installed on the hydraulic pipeline. The rolling force is calculated by detecting the pressure in the two chambers of the hydraulic cylinder and the areas of the two chambers.

[0007] (2) During the normal operation of the rolling mill, steel rolling control is mainly carried out with the ram rolling, and at the same time, the pressure sensor is used as a backup sensor.

[0008] (3) When an abnormal failure occurs to the ram during the rolling process, the rolling force detection of the rolling mill automatically switches to the pressure sensor for rolling, and at the same time, the ram alarm information is prompted on the human-machine interface.

[0009] (4) After the ram failure is handled, cancel the pressure sensor through the human-machine interface, select the ram for the rolling mill calibration. After the calibration is completed, it will return to the original ram rolling state to prepare for the next abnormal switch.

[0010] The abnormal failure of the ram in step (3) includes the following situations:

[0011] a. When the ram health signal is lost or a failure occurs, it automatically switches to the pressure sensor for rolling.

[0012] b. When the rolling force of the ram exceeds the system upper limit, it automatically switches to the pressure sensor for rolling.

[0013] c. When the rolling force detected by the ram lags behind the rolling force detected by the pressure sensor for a specified duration, it automatically switches to the pressure sensor for rolling.

[0014] d. When the rolling force value detected by the ram remains unchanged, it automatically switches to the pressure sensor for rolling.

[0015] When any of the above situations is met, the function of automatically switching the pressure sensor is triggered.

[0016] In step c, the specified duration is optimized and adjusted according to the actual on-site conditions to avoid false signals.

[0017] In step c, the value detected by the ram changes in real time, and the values detected in each scan time are different. When the ram controller freezes, the value remains unchanged. If the values are consistent within three scan cycles, it is proved that the rolling force value detected by the ram remains unchanged, and it is determined that the ram controller freezes, and it automatically switches to the pressure sensor for rolling.

[0018] The pressure sensor must be in a normal state before the pressure head can be automatically switched to the pressure sensor for rolling; the function of automatically switching to the pressure sensor must be carried out in the rolling mode; before rolling, the rolling mill is calibrated to zero the pressure values of the pressure head and the pressure sensor, ensuring that the force generated during rolling is the rolling force acting on the strip steel.

[0019] The beneficial effects of the present invention are as follows: eliminating the influence of human factors and reducing the rolling line shutdown accidents caused by pressure head failures; automatically calibrating and zeroing the pressure head and the pressure sensor during the calibration process of the rolling mill. When the pressure head fails or the detection is abnormal, the system automatically switches to the pressure sensor for rolling, and then notifies the operator to check through an alarm, ensuring that the production line does not stop and avoiding the occurrence of steel piling accidents. Brief Description of the Drawings

[0020] Figure 1 is the working flow chart of the present invention;

[0021] Figure 2 is the side view of the present invention;

[0022] Figure 3 is the front view of the present invention;

[0023] In the figure: drive side pressure head 1, operator side pressure head 2, drive side hydraulic cylinder 3, operator side hydraulic cylinder 4, drive side rodless cavity pressure sensor 5, drive side rod cavity pressure sensor 6, operator side rodless cavity pressure sensor 7, operator side rod cavity pressure sensor 8, upper backup roll 9, upper work roll 10, strip steel 11, lower work roll 12, lower backup roll 13, pressure head 14, hydraulic cylinder 15, hydraulic pipeline 16, rolling mill 17. Detailed Description of the Invention

[0024] In order to make the objectives, technical solutions, and advantages of the invention implementation cases clearer, the technical solutions in the invention implementation cases will be clearly and completely described below in conjunction with the drawings in the implementation cases. Obviously, the described implementation cases are a small part of the implementation cases of the present invention, rather than all of them. Based on the implementation cases of the present invention, all other implementation cases obtained by those of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

[0025] A device for automatically switching a mill platen to a pressure sensor, characterized in that it includes a platen 14 and a pressure sensor. The platen 14 includes a drive-side platen 1 and an operator-side platen 2, and the drive-side platen 1 and the operator-side platen 2 are respectively installed below the drive side and the operator side of the lower backup roll 13. The pressure sensor includes a drive-side rodless cavity pressure sensor 5, a drive-side rod cavity pressure sensor 6, an operator-side rodless cavity pressure sensor 7, and an operator-side rod cavity pressure sensor 8. The drive-side rodless cavity pressure sensor 5 and the drive-side rod cavity pressure sensor 6 are respectively installed on the hydraulic pipelines of the rod cavity and the rodless cavity of the drive-side hydraulic cylinder 3, and the operator-side rodless cavity pressure sensor 7 and the operator-side rod cavity pressure sensor 8 are respectively installed on the hydraulic pipelines of the rod cavity and the rodless cavity of the operator-side hydraulic cylinder 4.

[0026] A control method for automatically switching a mill platen to a pressure sensor includes the following steps:

[0027] (1) The drive-side platen and the operator-side platen are installed below the lower backup roll of the mill to directly detect the rolling force. The drive-side rodless cavity pressure sensor, the drive-side rod cavity pressure sensor, the operator-side rodless cavity pressure sensor, and the operator-side rod cavity pressure sensor are installed on the hydraulic pipelines to calculate the rolling force by detecting the pressure in the two chambers of the hydraulic cylinder and the areas of the two chambers.

[0028] (2) During the normal operation of the mill, the platen is mainly used for rolling steel control, and at the same time, the pressure sensor is used as a backup sensor.

[0029] (3) During the rolling process, when an abnormal failure occurs to the platen, the rolling force detection of the mill is automatically switched to the pressure sensor for rolling, and at the same time, a platen alarm message is prompted on the human-machine interface.

[0030] (4) After the platen failure is processed, cancel the pressure sensor through the human-machine interface, select the platen for mill calibration, and after the calibration is completed, restore to the original platen rolling state to prepare for the next abnormal switch.

[0031] The abnormal failures of the platen in step (3) include the following situations:

[0032] a. When the platen health signal is lost or a failure occurs, it is automatically switched to the pressure sensor for rolling;

[0033] b. When the rolling force of the platen exceeds the system upper limit, it is automatically switched to the pressure sensor for rolling;

[0034] c. When the rolling force detected by the platen lags behind the rolling force detected by the pressure sensor for a specified duration, it is automatically switched to the pressure sensor for rolling;

[0035] d. When the rolling force value detected by the platen remains unchanged, it is automatically switched to the pressure sensor for rolling;

[0036] If any of the above situations is satisfied, the function of automatically switching the pressure sensor is triggered.

[0037] In step c, the specified duration is optimized and adjusted according to the actual on-site conditions to avoid false signals.

[0038] In step c, the value detected by the ram head changes in real time, and the values detected in each scanning time are different. When the ram head controller crashes, the value remains unchanged. If the values are consistent within three scanning cycles, it is proved that the rolling force value detected by the ram head remains unchanged, and it is determined that the ram head controller has crashed, and it automatically switches to the pressure sensor for rolling.

[0039] The pressure sensor must be in a normal state before the ram head can be automatically switched to the pressure sensor for rolling; the function of automatically switching to the pressure sensor must be carried out in the rolling mode; before rolling steel, the rolling mill is calibrated, and the pressure values of the ram head and the pressure sensor are cleared to ensure that the force generated during rolling is the rolling force acting on the strip steel.

[0040] In practical applications, the calculation formula for the strip steel rolling force:

[0041] F 压头轧制力 =F 驱动侧压头 +F 操作侧压头 -F 压头标定补偿值

[0042] F 压力传感器轧制力 =F 驱动侧 +F 操作侧 = (P 驱动侧无杆腔压强 * S 驱动侧无杆腔面积 - P 驱动侧有杆腔压强 * S 驱动侧有杆腔面积 ) + (P 操作侧无杆腔压强 * S 操作侧无杆腔面积 - P 操作侧有杆腔压强 * S 操作侧有杆腔面积 ) - F 压力标定补偿值

[0043] Each rolling mill includes two ram heads, the drive side ram head 1 and the operating side ram head 2, which are respectively installed below the drive side and the operating side of the lower backup roll 13 of the rolling mill. The sum of the rolling forces detected by the two side ram heads gives the rolling force F acting on the strip steel 压头轧制力 , and each rolling mill includes four pressure sensors, the rodless cavity pressure sensor 5, the drive side rod cavity pressure sensor 6, the operating side rodless cavity pressure sensor 7 and the operating side rod cavity pressure sensor 8, which are respectively installed on the hydraulic pipelines of the rod cavity and the rodless cavity of the drive side and the operating side hydraulic cylinders. By detecting the pressure of the hydraulic oil on both sides of the hydraulic cylinder and then calculating the sum of the rolling forces on both sides according to the areas of the rod cavity and the rodless cavity of the hydraulic cylinder, the rolling force F acting on the strip steel is obtained. 压力传感器轧制力. During the normal operation of the rolling mill, steel rolling control is mainly carried out by the indenter rolling. At the same time, the pressure sensor is used as a backup sensor. Before steel rolling, the rolling mill is calibrated, and the pressure values of the indenter and the pressure sensor are cleared simultaneously (update F 压头标定补偿值 and F 压力标定补偿值 values), ensuring that the force generated during rolling is the rolling force acting on the strip steel. The human-machine interface includes buttons for selecting the indenter and the pressure sensor. During rolling, when an abnormal fault occurs in the indenter, the rolling force detection of the rolling mill automatically switches to the pressure sensor for rolling. At the same time, the indenter alarm information is prompted on the human-machine interface. After the personnel complete the handling of the indenter fault, they can re-select the indenter through the human-machine interface for calibration and then resume indenter rolling after completion.

[0044] The specific steps are as follows:

[0045] (1) Calibrate the rolling mill before starting, update F 压头标定补偿值 and F 压力标定补偿值 values, so that during the idling process of the rolling mill, the rolling forces F 压头轧制力 =F 压力传感器轧制力 =0 of the indenter and the pressure sensor of the rolling mill.

[0046] (2) The pressure sensor must be in a normal state during normal production to ensure that the pressure sensor can be used for rolling at any time.

[0047] (3) The function of automatically switching to the pressure sensor must be carried out in the rolling mode.

[0048] (4) When the following abnormal faults occur in the indenter, it can be automatically switched to the pressure sensor for rolling according to the control timing:

[0049] a. When the indenter health signal is lost or a fault occurs, it is automatically switched to the pressure sensor for rolling.

[0050] b. When the rolling force of the indenter exceeds the system upper limit set to 24700 kN (tentatively 95% of the indenter upper limit of 26000 KN, different upper limits have different set values), it is automatically switched to the pressure sensor for rolling.

[0051] c. When the rolling force detected by the indenter lags behind the rolling force detected by the pressure sensor by more than 200 (a) milliseconds (a can be optimized and adjusted according to the actual on-site conditions to avoid false signals), it is automatically switched to the pressure sensor for rolling.

[0052] d. When the rolling force value detected by the indenter remains unchanged (the rolling force detected by the indenter changes in real time, and the values detected at each scanning time are different. When the indenter controller freezes, the value remains unchanged. It is set that if the values are the same within three scanning cycles, it is proved that the value remains unchanged and the controller is judged to be frozen), it is automatically switched to the pressure sensor for rolling.

[0053] At any moment during the steel rolling production process, when an abnormal fault occurs in the platen, the controller automatically switches the platen rolling to the pressure sensor for rolling, triggers an alarm on the human-machine interface to indicate a platen fault, and maintenance personnel carry out maintenance. After the platen fault is handled, during the downtime of the rolling line, the operator selects a button through the human-machine interface to cancel the pressure sensor and select the platen for rolling mill calibration. After the calibration is completed, it returns to the original platen rolling state.

Claims

1. A control method for automatically switching a mill pressure head to a pressure sensor, characterized in that The control is carried out by adopting a device for automatically switching a mill ram into a pressure sensor. The device comprises a ram (14) and a pressure sensor. The ram (14) comprises a drive-side ram (1) and an operator-side ram (2). The drive-side ram (1) and the operator-side ram (2) are respectively installed below the drive side and the operator side of the lower backup roll (13). The pressure sensor comprises a drive-side rodless cavity pressure sensor (5), a drive-side rod cavity pressure sensor (6), an operator-side rodless cavity pressure sensor (7) and an operator-side rod cavity pressure sensor (8). The drive-side rodless cavity pressure sensor (5) and the drive-side rod cavity pressure sensor (6) are respectively installed on the hydraulic pipelines of the rod cavity and the rodless cavity of the drive-side hydraulic cylinder (3). The operator-side rodless cavity pressure sensor (7) and the operator-side rod cavity pressure sensor (8) are respectively installed on the hydraulic pipelines of the rod cavity and the rodless cavity of the operator-side hydraulic cylinder (4). It is characterized in that the following steps are included: (1) The drive-side ram and the operator-side ram are installed below the lower backup roll of the mill to directly detect the rolling force. The drive-side rodless cavity pressure sensor, the drive-side rod cavity pressure sensor, the operator-side rodless cavity pressure sensor and the operator-side rod cavity pressure sensor are installed on the hydraulic pipelines, and the rolling force is calculated by detecting the pressure of the two cavities of the hydraulic cylinder and the areas of the two cavities; (2) During the normal operation of the mill, the rolling steel control is mainly carried out by using the ram, and at the same time, the pressure sensor is used as a backup sensor; (3) During the rolling process, when an abnormal fault occurs to the ram, the rolling force detection of the mill is automatically switched to the pressure sensor for rolling, and at the same time, the ram alarm information is prompted on the human-machine interface; (4) After the ram fault is processed, cancel the pressure sensor through the human-machine interface, select the ram to calibrate the mill. After the calibration is completed, it will return to the original ram rolling state to prepare for the next abnormal switch; The abnormal faults of the ram in the step (3) include the following situations: a. When the ram health signal is lost or a fault occurs, it is automatically switched to the pressure sensor for rolling; b. When the rolling force of the ram exceeds the system upper limit, it is automatically switched to the pressure sensor for rolling; c. When the rolling force detected by the ram lags behind the rolling force detected by the pressure sensor for a specified time, it is automatically switched to the pressure sensor for rolling; d. When the rolling force value detected by the ram remains unchanged, it is automatically switched to the pressure sensor for rolling; If any of the above situations is satisfied, the function of automatically switching the pressure sensor is triggered; In the step c, the detected value of the ram changes in real time, and the values detected in each scanning time are different. When the ram controller crashes, the value remains unchanged. If the values are consistent within three scanning periods, it is proved that the rolling force value detected by the ram remains unchanged, and it is judged that the ram controller crashes, and it is automatically switched to the pressure sensor for rolling.

2. The control method for automatically switching a rolling mill pressure head to a pressure sensor according to claim 1, characterized in that: In the step c, the specified time is optimized and adjusted according to the actual on-site conditions to avoid false signals.

3. The control method for automatically switching the mill press head to a pressure sensor according to claim 1, characterized in that: The pressure sensor must be in a normal state before the pressure head can be automatically switched to the pressure sensor for rolling; the function of automatically switching to the pressure sensor must be carried out in the rolling mode; before rolling, the rolling mill is calibrated to zero the pressure values of the pressure head and the pressure sensor, ensuring that the force generated during rolling is the rolling force acting on the strip steel.

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