JP2938310B2 - Mold width change control method for continuous casting equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling a mold width change in a continuous casting facility.

[0002]

2. Description of the Related Art For example, an electrohydraulic servo (pulse) cylinder operated by a stepping motor disclosed in Japanese Utility Model Publication No. 58-10004 is applied to an actuator for controlling a mold width change in a continuous casting facility.
The upper and lower two are installed on the short side plate of the mold.

[0003] In the conventional continuous casting equipment, mold width change control before casting is performed by setting the position and gradient of the short side plate of the mold in advance and moving the two upper and lower electrohydraulic servo cylinders of the short side plate of the mold. The mold short side plate is set at the set position and slope.

As a control method in this case, a difference between the current position of each of the upper and lower two electro-hydraulic servo cylinders and the distance between the next set value is calculated, and a drive command pulse corresponding to the difference distance is generated by a stepping motor. A mechanism for converting the rotation of the stepping motor into a linear displacement of the valve spool and moving the piston rod connected to the short side plate of the mold by appropriately increasing the hydraulic pressure difference between both ends of the piston caused by this displacement. Is used.

[0005] An angle sensor for detecting a rotation angle is attached to the stepping motor.
By comparing the drive command pulse with the output pulse from the angle sensor and managing the pulse difference P, normal operation can be confirmed. If a difference between the pulse difference P and the control value exceeds a control value, a phenomenon called step-out occurs. Wake up, stop output of drive command pulse, and issue alarm. At this time, since the current position is deviated from the control position, it is necessary to input the actually measured current position again to the control device.

In the operation of setting the mold short side plate to the next casting width in the casting preparation work, it is necessary to set the mold short side plate at a certain distance from the dummy bar head, and when the dummy bar head position shifts, Requires manual intervention and requires a long time for the set operation.

[0007]

In the recent continuous casting process, automation and labor saving of each operation are being promoted toward a highly efficient manufacturing process. Contributes to shortening of production and leads to improvement of productivity.

In particular, in the operation of setting the short side plate of the mold to the next casting width, the conventional method of changing the width of the mold requires time and manpower for the following setting operation, thereby improving productivity and saving labor. There is a problem in terms of.

(1) For the control method of setting the set position of the short side plate of the mold in advance, it is necessary to set the value in consideration of the amount of head displacement of the dummy bar, which is time-consuming. (2) Since the head displacement of the dummy bar is not strictly measured in the operation, fine adjustment of the position of the short side plate of the mold is finally required. (3) If a step-out is detected during the operation, a deviation occurs between the current position and the control position. Therefore, it is necessary to measure the actual short side position again and input it to the control device.

In view of the above circumstances, the present invention has been devised in order to provide a mold width changing control method that can easily and quickly set the short side plate of the mold to the next casting width.

[0011]

The technical means of the present invention for solving the above-mentioned problems utilizes a step-out phenomenon in a conventional control method, and a dummy bar head is mounted in a mold. In this state, the side plate of the mold is moved in the direction of the dummy bar head and forcedly collided (step out) to recognize the position of the dummy bar head (upper and lower electrohydraulic servo cylinder positions) and to control the electrical control position and mechanical The deviation from the short side position (cylinder position) is corrected, and the mold short side plate is stopped at a position separated from the dummy bar by a distance obtained by adding a play amount of the valve spool to a preset gap distance. Things.

[0012]

According to the above construction, when the stepping motor is rotated, the electrohydraulic servo cylinder performs a predetermined movement by converting the rotation into a linear displacement of the valve spool and an increasing movement of the piston rod. When the short side plate of the mold collides with the dummy bar head, the piston rod stops, but the valve spool continues to move until there is no play. When the play amount of the valve spool is lost, the pulse output from the angle sensor is interrupted because the valve spool stops.

On the other hand, at this time, the drive command pulse continues to be output, and when the difference between both pulses exceeds P, the step-out occurs, and the output of the drive command pulse is interrupted. The current position is recognized when the upper and lower electrohydraulic servo cylinders lose synchronism, the electrical control position is further corrected by P, and the play amount of the valve spool is added to the preset gap distance (movement distance). The electro-hydraulic servo cylinder is retracted by the specified distance.

[0014]

FIG. 1 shows an embodiment of the present invention. A description will be given based on FIG. The mold short side plate 1 of the continuous casting equipment includes:
An electrohydraulic servo cylinder 2 (up and down two) operated by a stepping motor is installed as a width changing control actuator.

This width changing control actuator controls the rotation of the stepping motor 3 in the same manner as in the prior art.
And an electric hydraulic servo cylinder 2 for moving the piston rod 5 connected to the mold short side plate 1 by appropriately increasing the pressure by the oil pressure difference between both ends of the piston caused by this displacement, and the rotation of the stepping motor 3. Angle sensor (pulse transmitter) for detecting the angle of a beam
6 and a comparison between the output pulse from the angle sensor 6 and the drive command pulse to determine step-out, correct the electric current position after step-out detection, and move the mold short side plate 1 to a predetermined position. And a pulse for driving the stepping motor 3
7 mainly comprises a controller 8 which also has a control means for outputting to the controller 7.

FIG. 2 shows the moment when the short side plate 1 of the mold collides with the dummy bar head 9. At this time, the piston rod 5 stops because the valve spool 4 has the play amount α, but the valve spool 4 does not stop.

FIG. 3 shows that the valve spool 4 has moved further and has advanced from the position of FIG. 2 by the play amount α.
The left surface 10 of the valve spool 4 is the inner wall 1 of the spool chamber 11
I'm just sitting on 2. Up to this point, there is no difference between the output pulse from the angle sensor 6 and the drive command pulse. However, when the valve spool 4 stops and a difference of P occurs between both pulses, the drive output pulse is stopped. At this time, the electrical current position is corrected by P pulses. For example, in the present embodiment, P is set to 63 pulses (1 pulse = 0.01 mm), so correction for 63 pulses, that is, correction (addition) of 0.63 mm may be performed.

Next, after both upper and lower cylinders 2 detect step-out, the controller 8 calculates a pulse value corresponding to a distance obtained by adding a clearance set distance between the mold short side plate 1 and the dummy bar head 9 to the play amount α. The output is output to the drive unit 7, and the valve spool 4 is retracted. At this time, the piston rod 5 starts operating when the valve spool 4 has moved by the play amount α. FIG. 4 shows a state at the time of completion of the operation.

When the mold short-side plate 1 is set at a certain distance from the dummy bar head 9, if the gradient is set to 0 (vertical), a shift occurs in the step-out timing of the upper and lower cylinders 2. When (steps did not step out at the same position), for the cylinders that stepped out later on the basis of the cylinders that stepped out earlier, the difference between the distances may be added to the above-described movement distance. The above series of operations is shown in the flowchart of FIG.

[0020]

Since the present invention has the above-described structure and operation, the following effects can be obtained. With the dummy bar head mounted in the mold, the short side plate of the mold is moved in the direction of the dummy bar head, and by forcibly colliding, the position of the dummy bar head is recognized, and the electrical control position and the mechanical short side position are compared. With the control means to stop the mold short side plate at a position separated from the dummy bar by the distance obtained by adding the amount of play of the valve spool to the gap distance set in advance and correcting the deviation, before casting with one touch Since the setting of the mold short side plate is completed, the casting preparation time can be greatly reduced. Further, since the step-out phenomenon is used, no manual intervention is required during the present control. As described above, not only can the casting preparation work be automated, but also the preparation time can be reduced, and continuous casting can be quickly resumed, so that productivity can be improved and labor can be saved.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an embodiment of a width changing control actuator of a continuous casting facility according to the present invention.

FIG. 2 is a view showing a moment when a short side plate of the mold in FIG. 1 collides with a dummy bar head.

FIG. 3 is a view showing a state where the valve spool of FIG. 2 has advanced by an amount of play α.

FIG. 4 is a diagram showing a state in which operation is completed.

FIG. 5 is a flowchart for explaining the operation of FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Mold short side plate 2 Electro-hydraulic servo cylinder 3 Stepping motor 4 Valve spool 5 Piston rod 6 Angle sensor (pulse transmitter) 7 Drive unit (Drive unit) 8 Controller 9 Dummy bar head 10 Left side of valve spool 11 Spool chamber 12 Spool chamber inner wall

Continuation of the front page (72) Inventor Toshio Kikuchi 46-59 Ohara Nakahara, Tobata-ku, Kitakyushu-shi, Fukuoka Nippon Steel Corporation Machinery & Plant Business Department (56) References Tokiko Hei 2-1591 (JP, B2) 58-10004 (JP, Y2) (58) Field surveyed (Int. Cl. ⁶ , DB name) B22D 11/16 106 B22D 11/04 316

Claims (1)

(57) [Claims] 1. A control method in which a short side plate of a mold having both upper and lower electrohydraulic servo cylinders in a continuous casting facility is moved before casting to change the width thereof.
With the dummy bar head mounted in the mold, the short side plate of the mold is moved in the direction of the dummy bar head, and the dummy bar head position is recognized by forcibly colliding, and the electrical control position and the actual mechanical short side position A mold width change control method for continuous casting equipment, wherein the gap between the mold short side plate and the dummy short bar is stopped at a position apart from the dummy bar by a predetermined gap distance.