KR100411272B1 - Apparatus and method for automatically determining initial position of roll gap in plate mill - Google Patents

Abstract

The present invention is to reduce the time for the initial setting of the roll gap by setting the hydraulic position of the hydraulic cylinder and the initial position of the roll gap without the manual operation of complex operation procedures and risk of equipment damage due to errors and mistakes The present invention relates to a roll gap automatic positioning device and a method of a thick plate rolling mill capable of improving a setting accuracy, wherein the device and method are used to determine a pouring position by raising a hydraulic cylinder to a calculated height by calculating a casting height, and the rolling load is a roll gap. The screw motor is lowered until the first set value is set lower than the standard rolling load at the initial setting, and when the rolling load reaches the first set value, the hydraulic cylinder is raised so that the rolling load is the standard rolling at the initial roll gap setting. When the detected rolling load reaches the second set value while the second set value is the load, the positions of the screw and the hydraulic cylinder at this time are stored. After the hydraulic cylinder is lowered by a predetermined value, the screw is raised to the rolling ready position to complete the initial roll gap positioning.

Description

Roll gap automatic positioning device and method of thick plate rolling mill {APPARATUS AND METHOD FOR AUTOMATICALLY DETERMINING INITIAL POSITION OF ROLL GAP IN PLATE MILL}

The present invention relates to a thick plate rolling mill for producing slabs into a thick plate by applying a pressing force with a predetermined rolling force, and more particularly, automatically sets the zero point position of the roll gap as a reference for positioning the rolling mill during rolling. It relates to a roll gap automatic positioning device and method of a thick plate rolling machine.

In general, the thick plate rolling mill is a facility for producing slabs into thick plates having a desired thickness by pressing down with a rolling force of up to 7000 tons using an 8800 ton repulsion measuring device. The position of the rolling mill for obtaining a desired rolling force is set in consideration of the elongation of the roll, hysteresis by the reduction force, and the like.

At this time, since the positioning of the rolling mill is made based on the zero position (0 mm) of the roll gap, the zero position of the roll gap should be accurately set during the initial operation.

In the conventional method of setting the roll gap position of the thick plate rolling mill, as shown in FIG. 3, the driver moves the driving unit to contact the upper and lower rolls 1A, 1B, 3A, and 3B by hand, and the load cell located in the screw nut. Since the rolling load is checked according to (7) to match the point at which the rolling load becomes a desired value (for example, 1400 tons), it is difficult to accurately match the rolling load, but conventionally a screw motor which is a pressing device Since the load is moved by (6), the load cannot be applied unless it is moved up to 1400 ton at a time. There is a problem that the initial position of the roll gap must be set while operating the screw motor several times.

More specifically, the conventional roll gap initial setting operation will be described. In order to manually set the roll gap, first, check the diameters BDwrd and BDdrd of the lower work roll 1B and the backup roll 3B, and then Check the thickness A, set the height difference d between the lower work roll 1B and the roller table 2, calculate the oil column height S from this, and let the driver manually The cylinder 5 is raised.

Manually raise the hydraulic cylinder (5) as described above and move it to the calculated position, and then use the screw motor (6) installed on the upper side to lower the load down to 1400 tons of the reference load for initial roll gap positioning. .

Here, when pressing down, if the screw motor does not descend to 1400 tons at a time, the power of the screw motor is insufficient and cannot move. Therefore, when the desired load is not applied, the roll gap must be opened and then pressed again, which causes a problem in that roll gap initial positioning takes a long time. In addition, if the load of the workside and the driveside of the thick plate rolling machine does not match even when the rolling load is 1400 tons, the camber of the raw material is generated during rolling.If the load difference occurs after setting the roll gap, the workside and the driveside are connected. The screw drive shaft must be removed to change the screw position by the rolling force deviation, and the roll gap initial position must be adjusted again.

Therefore, the conventional manual work adds inconvenience to the driver and the load of work, and there is a problem that excessive work time is required.

The present invention has been made in order to solve the conventional problems as described above, the object is to automatically set the position of the jujube without the manual operation of complicated operation procedure and risk of equipment damage by error and error It is to provide a roll gap automatic positioning apparatus and method for a thick plate rolling mill that can determine the initial position of the roll gap to improve time reduction and setting accuracy.

1 is a graph showing the results of measuring a mill constant in a thick plate mill.

FIG. 2 is a schematic diagram for explaining a process of calculating a pass line position of a hydraulic cylinder driving a thick plate mill.

3 is a flowchart showing a conventional roll gap initial positioning method by manual.

4 is a flowchart schematically showing a roll gap automatic positioning method according to the present invention.

FIG. 5 is a detailed flowchart showing each step shown in FIG. 4 in detail.

6 is a block diagram showing a roll gap automatic positioning device according to the present invention.

* Description of the symbols for the main parts of the drawings *

1A: Upper work roll 1B: Lower work roll

2: roller table 4: softliner

3A: Upper backup roll 3B: Lower backup roll

5: hydraulic cylinder 6: screw motor

7: Load Cell 8: Cylinder Position Detector

9: Screw position detector 10: Hydraulic control servo valve

11: Hydraulic cylinder quick drop valve

As a constitutional means for achieving the above object of the present invention, the roll gap automatic positioning method of the thick plate rolling mill according to the present invention

A first step of determining the oil filling position by raising the hydraulic cylinder to the calculated height by calculating the basic oil pouring height from the setup value of the thick plate mill;

A second step of lowering the screw motor until the rolling load becomes a first set value lower than the reference rolling load at the initial setting of the roll gap;

A third step of raising the hydraulic cylinder when the rolling load reaches the first set value so that the rolling load becomes a second set value that matches the reference rolling load at the initial setting of the roll gap;

When the detected rolling load reaches the second set value, the position of the screw and the hydraulic cylinder at this time is memorized and the hydraulic cylinder is lowered by a predetermined value, and then the screw is raised to the rolling ready position to complete the roll gap initial positioning. It is characterized by consisting of steps.

In addition, the roll gap automatic positioning method of the thick plate mill

The fourth step may further include a fifth step of changing the drift position by compensating for the deviation when there is a deviation by comparing the rolling load of the work side and the rolling load of the drive side after the initial positioning of the roll gap.

In addition, the roll gap automatic positioning device of the thick plate rolling mill according to the present invention

A screw motor position detector for detecting a falling position of the screw motor and displaying the position thereof;

Detects the rolling load generated by the upper and lower rolls, respectively, by lowering / rising, so as to be less than or equal to a first set value lower than a reference rolling load for initial roll gap positioning. A rolling force detector for comparing between a second set value coinciding with the reference rolling load,

The speed control value is calculated so as to calculate the lubrication position at the initial setting of the roll gap, and to check the current detection value of the screw motor position detector to descend at high speed while the roll gap of the upper and lower rolls is more than a predetermined value, and to lower at a low speed within the predetermined value. A data processing and screw speed determiner which is applied to the screw motor controller and stores the hydraulic cylinder position and the screw position detected by each detector when the rolling load value reaches the second set value;

The screw which checks the current position detected by the screw motor position detector and moves the screw motor down at the set speed applied from the data processing and screw speed determiner until the rolling force detector determines that the rolling load is the first set value. Motor controller,

A cylinder position detector for detecting a position of a hydraulic cylinder driving the lower roll;

After the roll gap initial setting operation starts, place the hydraulic cylinder at the oil pressure position calculated by the data processing and screw speed judging machine, and if the current rolling load in the rolling force detector is greater than or equal to the first set value, Characterized in that it consists of a hydraulic cylinder controller for raising the hydraulic cylinder.

Hereinafter, a roll gap automatic positioning apparatus and method according to the present invention will be described with reference to the accompanying drawings.

4 is a flowchart illustrating a roll gap automatic positioning method according to the present invention, and FIG. 5 is a flowchart showing the roll gap automatic positioning method shown in FIG. 4 in more detail.

4 and 5, the roll gap automatic positioning according to the method of the present invention includes the first step of determining the position of the pass line, that is, the height of the hydraulic cylinder column by calculating the height of the hydraulic cylinder column. 410, a second step 420 of lowering the upper screw at a high speed from an arbitrary position to a setting position slightly higher than the kiss roll position, and then lowering it at a low speed until the pressing force becomes an initial setting value; The third step 430 of raising the oil column until the second setting value of the pressing force is controlled by controlling the hydraulic cylinder of the hydraulic cylinder, and storing the current position value to determine the initial position of the roll gap, and After the cylinder's oil column is lowered by a predetermined value, the fourth step 440 of driving the screw motor to the set rolling ready position is compared with the rolling load of the work side and the rolling load of the drive side. To check whether there is a deviation, and to compensate for the deviation, if the deviation is divided by the mill constant, change the location of the injuries. Step 450 is made.

The operation of each step will be described in detail with reference to FIG. 5.

1) Step 1: Yuju Location

In order to set the initial position of the roll gap, first, the milling constant measurement graphs of the work side and the drive side as shown in FIG. 1 are used to determine the initial position of the roll gap as the portion where the rolling force changes linearly according to the change amount of the roll gap. , Set the position as the zero point (0.0mm). For example, with reference to Fig. 1, the rolling load showing linearity in the rolling load graphs for the cylinder positions of the workside and the driveside, that is, the cylinder position for 700 tons is set as the initial position.

And, as shown in Figure 2 for the initial position of the roll gap, after raising the hydraulic cylinder (5) to the oil position, the roll gap must be set, the initial position of the lower roll as shown in the following equation (1) Calculate the Yuju position for (412)

In the above, S is the circumferential position (height), d is the height difference between the lower work roll 1B and the roller table 2, L is the height from the cylinder base to the roller table 2, and BDwrd is the lower work roll. Diameter, BDbrd is the lower backup roll diameter, A is the softliner height, l1 backup roll reference value, l2 is the cylinder reference value, and l3 is the cylinder base base height.

As such, when the oil filling position is calculated, the hydraulic cylinder 5 is operated to raise the calculated oil filling position (413).

B) Step 2: Lowering the upper screw

The conditions for automatically lowering the screw to the initial position are checked (421).

Then, using each condition value to calculate the position for determining the falling speed of the screw as shown in Equation 2 (422)

That is, the time of changing the lowering speed of the screw motor 6 from the high speed to the low speed is obtained by adding the existing zero set position, the diameter deviation of the upper work roll, the diameter deviation of the lower work roll, the drift position deviation, and the margin value (10 mm). Is determined by subtracting the screw from the current position.

When the low speed change point is determined, first, the screw lowering control signal is outputted to descend at high speed (423), and when the calculated position (that is, the low speed change point) is reached, the falling speed of the screw motor is changed to low speed ( 424).

After slowly lowering from the low speed change point, the upper and lower work rolls 1A and 1B are in contact with each other (KISS), and when the rolling load reaches 500 tons, the screw motor is stopped (425).

C) Stage 3: Underfloor rise

As in the previous step, first check all the conditions for the lifting operation of the hydraulic cylinder (431).

Then, the lower hydraulic cylinder is raised until the rolling load reaches the reference load for setting zero (i.e., 1400 tons) (432, 433).

D) Step 4: Roll gap positioning

When the plate rolling mill becomes the state at the time of setting the roll gap zero by the action of the previous step as described above, the roll gap state is stored at the zero point, and the screw down position, the position of the hydraulic cylinder, the rolling of each work side and the drive side Each load is stored in the memory (441).

Then, to reduce the rolling load and raise the screw, the oil column is lowered by a predetermined position (about 3 mm) (442), and the screw motor is raised to the rolling ready position (443).

E) Step 5: Compensation for Roll gap deviation

This step is a process of checking the rolling load difference between the work side and the drive side after compensating the zero position of the roll gap to compensate for the deviation.

Therefore, when all the steps are processed and the roll gap position is stored, the roll load (p1) of the drive side and the roll load (p2) of the work side are read at this time, so as to prevent camber generation as shown in Equation 3 below. The camber compensation value is calculated (451).

Compensating and setting the inflow position based on the camber compensation value calculated as described above, the camber compensation value is lowered at the drive side on the drive side by 1/2 of the double-surface camber compensation value and at the work side. On the contrary, the camber compensation value is increased on the negative side and 1/2 of the camber compensation value on the drive side, while the camber compensation value is lowered on the drive side (452).

As described above, the zero position setting of the roll gap is completed. If there is no rolling load deviation between the drive side and the work side, the zero position setting is completed without correction of the position of the gap (453).

As shown in FIG. 6, the roll gap automatic positioning device of the thick plate rolling machine which operates automatically according to the above method is provided with the work side WS and the drive side DS from the pulse generator 9 installed in the screw motor 6. ), The screw motor position detector 61 calculates and displays the position of the screw motor 6 by multiplying the movement distance (for example, 40 μm) per pulse by inputting the position of 1000 pulses per revolution. For initial setting, the current screw position is calculated by averaging the drive side position and the work side position of the screw motor detected by the screw motor position detector 61, and the set value calculated by the roll diameter data of the rolling mill and the current screw position. The screw motor controller 62 which applies a control signal to the screw motor 6 to lower the motor at the input speed until the deviation becomes zero, and the first reference load (500 tons) at the time of initial determination of the roll gap. Rolling force detector for detecting the repulsive force generated during rolling in the rolling mill to lower the upper screw and raise the hydraulic cylinder between the first reference load and the second reference load (1400 tons) so as to apply the reduction. 63) and data processing and screw speed judgment to calculate fixed reference position at roll gap initial decision and to determine the speed of screw motor 6 by receiving fixed and variable data related to rolling mill by key input of another device or operator. The position of the hydraulic cylinder from the cylinder position detector 65 which detects and displays the rising position of the machine 64, the hydraulic cylinder 5 which raises a lower roll, and the roll gap initial stage at the time of initial setting. After calculating the average value of the work side of the drive side and comparing it with the data of the calculated Yuju line, it is controlled to rise to the target position and roll gap seconds After the presetting, the hydraulic cylinder controller 66 reads the load deviations of the drive side and the work side and raises and lowers the hydraulic cylinders of the drive side and the work side, respectively, so that there is no deviation.

In the above, the screw motor position detector 61 receives signals output from the pulse generator 9 of the screw motors installed on the drive side and the work side, respectively, to raise and lower the upper roll of the thick plate rolling mill. To calculate the screw motor moving position by multiplying the number of pulses input from the first and second pulse converters 611 and 612 and the first and second pulse converters 611 and 612 by the movement distance per pulse. A determination unit 614 for judging whether the position calculated by the position calculation unit 613 is a set target position and outputting a setting completion signal when the target position is a target position; and outputting from the position calculator 613. Position memory unit 615 for storing the screw motor movement position (DS, WS) of each of the drive side and the work side to be driven, and the screw motor movement position of each of the drive side and the work side output from the position calculator 613 A BCD converter 616 for transcoding so as to output the values DS and WS to the display 617, and a display 617 for displaying the position value of the upper screw motor 6.

The screw motor controller 62 is configured with a first operation unit 621 which calculates a position feedback value by averaging the screw motor position values WS and DS of the work side and the drive side to the position memory unit 615. A second operation unit 622 which calculates whether the target is reached by subtracting a feedback value output from the first operation unit 621 from a value S1, and a motor inputted from an output of the second operation unit 622 and other devices; An analog converter 623 for converting the drive speed set value into an analog signal capable of controlling the motor, and the motor control signal input through the analog converter 623 to the screw motor 6 to the screw motor ( 6) an analog output unit 624 for driving.

The rolling force detector 63 includes an analog input unit 631 for receiving the output signals of the load cells 7 of the drive side and the work side, and an output signal of the load cell 7 input through the analog input unit 631. An amplifying unit 632 for amplifying the signal into a signal in a predetermined range indicating a rolling load, a display unit 633 for displaying the rolling load detected according to the output signal of the amplifying unit 632, and the amplifying unit 632 The calculation unit 634 calculates the total rolling load by adding the input rolling load of the work side and the rolling load of the drive side, and the position feedback value K1 and the target position of the screw motor calculated from the screw motor controller 621. The screw motor controller 62 when the comparison unit 635 comparing the D) and the total rolling load TRF calculated by the operation unit 634 coincide with the first rolling load set value K2. First to apply a speed change signal to Low speed output unit 637 for outputting the set low speed value to the screw motor controller 62 when the position K1 of the screw motor reaches the target position D as a result of the comparison between the end portion 636 and the comparison unit 635. And a second determination unit 638 that outputs a setting completion signal when it is determined whether the total rolling load TRF calculated by the calculating unit 634 reaches the second rolling load setting value K3.

Then, the data processing and screw speed judging machine 64 has a reference value l1 of the lower backup roll 3B, a reference value l2 of the hydraulic cylinder 5, and a base, which are values which do not change in the CRT 641, the thick plate rolling mill. A fixed data input unit 642 for receiving the height l3 and the pouring position S, a data buffer 643 for storing the basic value and the set floating position value of each facility in the thick plate rolling mill, and the data buffer 643. The first operation unit 644 for summing up the diameters D1 and D2 of the upper work roll and the backup roll and the height of the column height Pd among the data of the upper and lower working rolls, and the screw position feedback value of the screw motor controller 62 are The determination unit 645 for determining whether the output unit D is larger than the output value D of the operation unit 644, and the height value of each device is input from the fixed data input unit 642 and the data buffer unit 643. The second calculation unit 646 for calculating the position S and the determination unit 645 determines the current feedback value K. 1) is smaller than the calculated value D, the high speed output unit 647 for outputting a high speed set value to the screw motor controller 62, and the current feedback value K1 as a result of the determination by the determination unit 645. If the calculated value D is smaller than the calculated value D, the setting value output unit 648 for outputting the position setting value S1 for initial setting of the roll gap of the screw motor to the screw motor controller 62 and the total rolling load TRF are When the second rolling load reference value K3 is reached, the oil position is completed, and the position of the upper screw reaches the target position, the first logic AND1 determines that the initial roll gap setting is completed, and the second operation unit 646. Is composed of the second logic AND2.

Then, the cylinder position detector 65 checks the output signal of the amplification unit 651 for amplifying the detection signal of the cylinder position detector 8 installed in the hydraulic cylinder 5, and checks the position of the cylinder. A stroke counter 652 for counting the number of times, an indicator 653 indicating a position of the cylinder counted at the stroke counter 652, and a position value of the cylinder counted at the stroke counter 652 to convert the BCD code. A BCD data output unit 654 and a storage unit 656 for storing position data output from the BCD data output unit 654.

In addition, the hydraulic cylinder controller 66 receives a position data of the cylinder detected by the cylinder position detector 65 and converts it into a signal of a set range, and a BCD data conversion unit 661 and the BCD data conversion unit 661. The calculation unit 662 for calculating an average of the hydraulic cylinder position values MPS1 and MPS2 of the drive side and the work side output from the drive side, and the cylinder position value MPS output from the operation unit 662 are the data processing and screw speeds. A judging unit 663 that determines whether the judging position S is calculated by the judging unit 64 and a second of the data processing and screw speed judging unit A third logic AND3 for outputting a high signal when the high signal is output from the logic AND2, a setting unit 664 for outputting a space setting signal when the high signal is output from the third logic AND3, and The cylinder position signal calculated by the calculating unit 662 Is an analog output unit 665 for outputting a servovalve control signal for driving the hydraulic cylinder 5 according to the camber correction signal, and a camberbo for calculating the rolling load deviation of the work side and the drive side, and outputting a correction value thereto. Digital conversion unit 667 for receiving the position signal of the hydraulic cylinder (5) moved by the output signal of the analog output unit 665 and the analog output unit 665, and the digital conversion unit 667 It consists of an output unit 668 for outputting the position of the cylinder input through.

Operation of the roll gap automatic positioning device of the thick plate rolling machine described above is performed in the same manner as in FIG. 4 and FIG. 5.

As described above, the present invention is an operation for determining the initial position of the roll gap of the thick plate rolling mill to roll the width of the thick plate, and automatically sets the height of the oil column, while automatically driving the screw to determine the initial roll gap, It can improve the accuracy of the initial setting position by appropriate automatic adjustment, and the operator has the effect of completing the initial setting of the roll gap with a single operation in a short time. It is also an excellent effect that can prevent damage to the equipment due to overpressure under pressure for the initial setting.

Claims (4)

In the roll gap automatic positioning method of a thick plate rolling mill, A first step of determining the oil filling position by raising the hydraulic cylinder to the calculated height by calculating the oil filling height from the basic value of the thick plate mill; A second step of lowering the screw motor until the rolling load becomes a first set value lower than the reference rolling load at the initial setting of the roll gap; A third step of raising the hydraulic cylinder when the rolling load reaches the first set value such that the rolling load becomes the second set value during the standard rolling load at the initial roll gap setting; When the detected rolling load reaches the second set value, the fourth step of storing the screw and the hydraulic cylinder at this time, lowering the hydraulic cylinder by a predetermined value, raising the screw to the ready position for rolling, and completing the initial roll gap positioning Roll gap automatic positioning method of a thick plate mill. The method of claim 1, wherein the roll gap automatic positioning method of the thick plate rolling mill is Roll gap automatic rolling mill further comprises a fifth step of changing the oiling position by compensating for the deviation when the rolling load of the work side is compared with the rolling load of the drive side after the initial positioning of the roll gap. Positioning method. In the roll gap automatic positioning device of a thick plate rolling mill comprising a screw motor for lowering the upper and lower rolls and the upper roll, and a hydraulic cylinder for raising the lower roll, A screw motor position detector for detecting a falling position of the screw motor and displaying the position thereof; Detects the rolling load generated by the upper and lower rolls, respectively, by lowering / rising, so as to be less than or equal to a first set value lower than a reference rolling load for initial roll gap positioning. A rolling force detector for comparing between a second set value coinciding with the reference rolling load, The speed control value is calculated so as to calculate the lubrication position at the initial setting of the roll gap, and to check the current detection value of the screw motor position detector to descend at high speed while the roll gap of the upper and lower rolls is more than a predetermined value, and to lower at a low speed within the predetermined value. A data processing and screw speed determiner which is applied to the screw motor controller and stores the hydraulic cylinder position and the screw position detected by each detector when the rolling load value reaches the second set value; Checking the current position detected by the screw motor position detector, and lowering the screw motor until the rolling force detector determines that the rolling load is the first set value at the set speed applied from the data processing and screw speed determiner. Screw motor controller, A cylinder position detector for detecting a position of a hydraulic cylinder driving the lower roll; At the start of the roll gap initial setting operation, the hydraulic cylinder is placed at the oil pressure position calculated by the data processing and screw speed judging machine, and if the current rolling load is greater than or equal to the first set value in the rolling force detector, A roll gap automatic positioning device for a thick plate mill, characterized by comprising a hydraulic cylinder controller for raising a hydraulic cylinder. According to claim 3, wherein the hydraulic cylinder controller Roll gap automatic positioning device for thick-plate rolling mill, characterized in that after the initial setting of the roll gap, the load deviations of the drive side and the work side are calculated and the oil pressure positions of the hydraulic cylinders of the drive side and the work side are raised and lowered respectively. .