JP3239983B2 - Level control device 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 level control device for a continuous casting facility for controlling the level of molten steel in a mold.

[0002]

2. Description of the Related Art Conventionally, a billet-size continuous casting facility is provided with a mold 1 having a predetermined sectional shape in advance as shown in FIG. Open dish stopper 3 and
The molten steel 5 in the tundish 4 is poured into the mold 1. At this time, the molten steel level in the mold 1 is measured by the γ-ray level meter 6, and the measured molten steel level PV is sent to the molten steel level controller 2. Here, the molten steel level controller 2 performs a proportional / integral or proportional / integral operation based on a deviation between the molten steel level PV measured by the γ-ray level meter 6 and a preset target value SV.
An integral / differential adjustment operation is executed to determine an operation output MV such that the molten steel level PV matches the target value SV. Then, the opening of the tundish stopper 3 is adjusted according to the operation output MV, and the molten steel level PV is set to the target value. The configuration is such that control is performed to obtain the value SV.

[0003]

Therefore, in controlling the molten steel level in the mold of the continuous casting facility as described above, the molten steel level is measured by using the gamma ray level meter 6. Is very narrow, from 0 to -150 mm, so that the molten steel level in the mold 1 does not rise to the measurement range of the γ-ray level meter 6 at the start of molten steel injection, but falls from the tundish 4 into the mold 1. There is a problem that erroneous detection that the molten steel level has reached the measurement stable region of the γ-ray level meter 6 due to the jump of the molten steel (hereinafter referred to as “splash”).

[0004] At this point, the molten steel 5 must be injected into the casting mold 1. However, it is determined that the molten steel level has reached the stable measurement range, and the operation of closing the tundish stopper 3 is performed. Accordingly, there is a possibility that the molten steel level controller 2 cannot appropriately control the molten steel level in the mold 1.

Therefore, it is conceivable to squeeze the tundish stopper 3 and inject the molten steel into the mold 1 during the opening operation of the tundish stopper 3 so that no splash occurs. Overcooling occurs in the mold 1 and causes cracking of the solidified molten steel in the mold 1, adversely affecting the quality of the product. Also, when the temperature is excessively cooled, it is difficult to pull the molten steel from the mold 1. Casting becomes impossible.

Further, as another level control system, the level control is not performed until the molten steel of the mold 1 reaches the measurement stable region of the gamma ray level meter 6,
It is conceivable to avoid a malfunction caused by the splash that occurs during that time.

However, the control method for avoiding the level control for a certain period of time to prevent the splash is not problematic if the molten steel to be injected into the mold 1 is of one kind. Therefore, the amount of increase in the molten steel level is not constant depending on the quality of each steel type.Therefore, the operator must set the time to avoid malfunction due to splash for each steel type. It is necessary to adjust the time while paying, but there is a problem that a large amount of time is spent for this time adjustment.

The present invention has been made in view of the above-mentioned circumstances, and continuously casts molten steel without being affected by splash and controls the level of molten steel in a mold, regardless of various types of steel. To provide a level control device.

[0009]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, an invention according to claim 1 is a level control device of a continuous casting facility for controlling the level of molten steel in a mold. Based on the molten steel level measured by the level meter, controls the opening of the tundish stopper, and adjusts the amount of molten steel injected from the tundish into the mold with molten steel level adjusting means, at the time of the first molten steel injection of each steel type, A control operation start time obtaining means for obtaining a time until the molten steel level in the mold enters the measurement stable region of the molten steel level meter, and registering this time as a control operation start time, is registered by the control operation start time obtaining means. at molten steel injection start steels the same steel species being, the Tan dishes stopper
Control command to bring it to the specified opening or full open state.
Supplying the molten steel level adjusting means and clocking operation
And an initial start operation control means for giving a control start command to the molten steel level adjustment means when the time by the clocking operation has passed the control operation start time. It is a level controller for continuous casting equipment.

[0010] The control operation start time obtaining means includes: when steel type information is received at the time of injecting molten steel of a certain steel type, injecting molten steel into a mold with a predetermined degree of opening or a fully open state, and while clocking the time. A type-of-steel-related-information acquiring means for sequentially taking in the molten steel level of the molten steel level meter, splash determination data set in advance, and a splash determination means for determining whether or not the molten steel level is a splash based on the determination data; and a splash determination. When the molten steel level reaches the measurement stable region of the molten steel level meter from the determination result of the means, the control operation start time for registering the clocking time as the control operation start time together with the steel type data obtained by the steel type related information obtaining means. And registration means.

According to the present invention, when the steel type information is received by the steel type related information acquisition means in the control operation start time acquisition means at the time of the first molten steel injection of each steel type, a predetermined opening degree or The molten steel is poured into the mold in the fully opened state. At the same time, time is counted, the molten steel level of the molten steel level meter is taken in, and the steel type information and the molten steel level are stored. In this process, the splash determination means causes the injected molten steel to jump, that is, a so-called splash phenomenon occurs, but determines whether or not the splash is based on predetermined splash determination data, and ignores the splash if it is a splash. To continue pouring molten steel. Then, from the determination result of the splash determination means, when it is determined that the molten steel level is not splash, and has reached the measurement stable region of the molten steel level meter, the control operation start time registration means, from the steel type information and the first molten steel injection. In addition to the time required to reach the measurement stable region (= control operation start time), time series data of the molten steel level is registered in a file or the like as necessary.

Therefore, when the molten steel of the same steel type as the registered steel type is subsequently injected, the predetermined opening degree or the fully opened state is set during the control operation start time, the splash is ignored, and the control operation start time has elapsed. At that time, if the molten steel level is controlled while controlling the opening of the tundisher stopper based on the original level control, the molten steel can be stably injected without being affected by the splash, regardless of the type of steel,
The level of molten steel in the mold can be controlled.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a configuration diagram showing an embodiment of a level control device of a continuous casting facility, and FIG.
FIG. 2 is a functional block diagram of the initial opening control device shown in FIG. 1.

The level control device of the continuous casting equipment includes a tundish 12 filled with molten steel 11 of a certain steel type, a mold 13 installed at a predetermined position below the tundish 12 and having a predetermined cross-sectional shape, and an external device attached to the tundish 12 The opening degree is set to an appropriate degree based on the opening degree operation signal input from the apparatus, and a tundish stopper 14 for injecting the molten steel 11 in the tundish 12 into the mold 13 and a mold for injecting when the tundish stopper 14 is opened. A molten steel level meter 15 such as a γ-ray level meter for measuring the molten steel level in 13 and the control operation start time at the time of the first molten steel injection of each steel type, and in addition to the steel type information and the control operation start time, if necessary, To register the time series data of molten steel level,
When the molten steel of the same steel type as the registered steel type is injected, the molten steel is injected into the mold as a predetermined opening degree or a fully opened state, and an initial opening degree control device 20 that outputs a control start command when the control operation start time has elapsed. At all times, the proportional value is calculated based on the deviation between the molten steel level measured by the molten steel level meter 15 and the target value.
It performs an integration or proportional / integral / differential adjustment operation to output an opening operation signal, and is constituted by a molten steel level adjusting unit 16 that performs level control according to the output of the initial opening control device 20 at the start of molten steel injection of a certain steel type. Have been.

The initial opening control device 20 includes a steel type input means 21 for inputting steel type information at the time of first molten steel injection and at the start of molten steel injection thereafter, a steel type initial level control program and a molten steel injection start control program. And a program data storage means 22 for storing the molten steel level measured by the molten steel level meter 15
3 and an output port 24 for giving an operation control command to the molten steel level adjusting unit 17; and steel type related information storage means 25 for storing steel type related information, that is, the steel type information, molten steel level measurement data, splash determination data for each steel type, and the like.
, A clock circuit 26 for clocking time, an initial start operation information storage file 27 for storing the steel type information, control operation start time data, and the like, and a data processing control unit 28.

The data processing control means 28 stores the steel type information based on the steel type initial level control program when steel type information is received from the molten steel information input means 21 at the first molten steel injection of a steel type. 25,
The molten steel is poured into the mold 13 while controlling the molten steel level adjusting unit 16 so that the tundish stopper 14 is at a predetermined opening degree or a fully opened state, and the clock circuit 26 is turned on to start the clocking operation, and , Molten steel level meter 15
A steel type related information acquisition unit 31 that sequentially takes in the molten steel level measured in step S and stores it in the steel type related information storage unit 25;
As shown in FIG. 3, a splash determination time is set in advance in the steel type related information storage means 25 and the like for each steel type. For example, the molten steel level of steel type A causes a splash as shown in FIGS. It is determined whether or not the molten steel level is within the stable range where the molten steel level meter 15 can measure, but has continued for a predetermined splash determination time T1, that is, whether or not the molten steel level is splash. Splash determination means 32 and the molten steel level is determined from the determination result of the splash determination means 32 by the molten steel level meter 1.
5 is reached, the steel type information acquired by the steel type related information acquiring means 31 and the clock time of the clock circuit 26 are registered in the initial start operation information storage means 27 as the control operation start time. The operation start time registration means 33 and the tundish stopper 14 are set to a predetermined opening degree or a fully opened state during the control operation start time after the start of molten steel injection of the same steel type as the steel type registered by the control operation start time registration means 33. Is supplied to the molten steel level adjuster 16 and, after the elapse of the control operation start time, the initial start operation control means 34 for introducing a control start instruction allowing the original level control to the molten steel level meter 15. It is configured.

Next, the operation of the apparatus configured as described above will be described. First, the splash determination time for each steel type is stored in the steel type related information storage unit 25 from an input device including the steel type information input unit 21 based on past experience and the like. In this state, at the time of the first molten steel injection of steel type A, steel type information A is input from steel type information input means 21.

Then, the steel type related information obtaining means 31
After inputting the steel type information A to the steel type related information storage means 25 in accordance with the steel type initial level control program of the program data storage means 22, a control command for setting the tundish stopper 14 to a predetermined opening degree or a fully open state is issued. It is supplied to the level meter 16. As a result, when the molten steel level adjuster 16 applies an operation output such that the opening degree becomes a predetermined opening degree or a fully opened state, the tundish stopper 14 opens,
Molten steel is injected from a tundish 12 into a mold 13.

On the other hand, the steel type related information acquiring means 31 turns on the clock circuit 26 to start the clocking operation, and sequentially takes in the molten steel level measured by the molten steel level meter 15 and stores it in the steel type related information storage means 25. I will remember. In the process of acquiring the steel type related information, when the molten steel level of the steel type A becomes a splash as shown in FIGS. 4A and 4B, that is, when the molten steel level enters a measurable stable region, the splash determination means 32, it is determined whether or not the molten steel level maintains a measurable stable region during a predetermined splash determination time T1, and when a deviation from the measurable stable region occurs within the determination time T1, a splash is generated. Is determined, and the predetermined opening degree or the fully opened state is maintained,
In addition, when the stable region where the molten steel level can be measured is maintained beyond the splash determination time T1, it is determined that the measured stable region has been reached.

Here, the control operation start time registration means 33
When receiving the determination signal that has reached the measurement stable region from the splash determination means 32, the steel type related information acquisition means 3
The steel type information acquired by step 1 and the clock time of the clock circuit 26 are registered in the initial start operation information storage means 27 as the control operation start time.

The above-described series of level control processes is performed every time molten steel of a new steel type is injected, and is sequentially registered in the initial start operation information storage means 27. Therefore, when steel type information is input from the steel type information input unit 21 thereafter, the initial start operation control unit 34 determines whether or not the steel type information is already registered in the initial start operation information storage unit 27,
If registered, the initial start operation information storage means 27
During the control operation start time registered in the first step, the control command for setting the tundish stopper 14 to the predetermined opening degree or the fully open state is supplied to the molten steel level adjusting section 16, and after the elapse of the control operation start time, the original control operation starts. A control start command allowing the level control is introduced into the molten steel level meter 15, and the level control is performed.

Therefore, according to the configuration of the embodiment as described above, when the molten steel of the first steel type is injected in advance, the molten steel level of the molten steel level meter 15 is taken in for each steel type and the time is clocked. When the molten steel level enters a stable range that can be measured by the molten steel level meter 15, it is determined whether or not the molten steel level is a splash based on the splash determination data, and when it is determined that the splash is determined, the tundish stopper 14 is closed. Instead, maintain the predetermined degree of opening or the fully open state and continue the injection of molten steel. Then, when it is determined that the molten steel level has completely reached the measurement stability region based on the splash determination data, the time is registered together with the steel type information, so that when the molten steel injection of the same steel type is started, the registered time is not changed. Since the molten steel injection is continued without controlling based on the molten steel level, even when handling a large number of steel types, the molten steel can be injected stably without being affected by the splash, and the operator has to adjust the molten steel injection time. Is eliminated, contributing to reduced burden.

Further, since the control operation start time is automatically obtained and registered at the time of injecting molten steel of the first steel type, the operation can be performed efficiently. In the above embodiment, the time is used as the splash determination data, but the change rate of the steel type may be used as the splash determination data.

[0024]

As described above, according to the present invention, the following various effects can be obtained. According to the first aspect of the present invention, it is possible to stably inject molten steel without being affected by splash and control the level of molten steel in a mold regardless of various types of steel. According to the second aspect of the present invention, the control operation start time can be automatically obtained and registered, so that the burden on the operator can be reduced and the operation can be performed efficiently.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing one embodiment of a level control device of a continuous casting facility according to the present invention.

FIG. 2 is a functional block diagram showing an embodiment of the initial rank control device of FIG. 1;

FIG. 3 is a diagram showing an example of a data arrangement of steel type related information.

FIG. 4 is a diagram showing a change state of a molten steel level of a steel type.

FIG. 5 is a configuration diagram of a conventional level control device of a continuous casting facility.

[Explanation of symbols]

11 ... molten steel, 12 ... tundish, 13 ... mold, 14 ...
Tundish stopper, 15 ... molten steel level gauge, 16 ...
Molten steel level adjuster, 20: initial opening control device, 21: steel type information input means, 25: steel type related information storage means, 26 ...
Clock circuit, 27: Initial start operation information storage means, 31: Steel type related information acquisition means, 32: Splash determination means, 3
3 ... Control operation start time registration means, 34 ... Initial start operation control means.

────────────────────────────────────────────────── ─── Continuation of front page (56) References JP-A-2-290657 (JP, A) JP-A-1-170568 (JP, A) JP-A-7-308744 (JP, A) JP-A-62-1987 89556 (JP, A) JP-A-8-206805 (JP, A) JP-A-4-259016 (JP, A) JP-A-62-270264 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B22D 11/18 B22D 11/16 G05B 19/05 G05D 9/12

Claims (2)

(57) [Claims] A level controller for a continuous casting facility for controlling the level of molten steel in a mold, wherein the opening degree of a tundish stopper is controlled based on the level of molten steel measured by a molten steel level meter installed in the mold. From the molten steel level adjusting means for adjusting the amount of molten steel to be injected into the mold, and at the time of the first molten steel injection of each steel type, determine the time until the molten steel level in the mold enters the measurement stable area of the molten steel level meter. a control operation start time acquiring means for registering the time as a control operation starting time, the same steel species molten steel injection start and <br/> grades that are registered by the control operation start time acquiring unit, said Tandesshusu
Control to bring the topper to a specified opening or fully open
Supply a command to the molten steel level adjusting means and
Starting the operation, when the time by the clocking operation has elapsed the control operation start time, an initial start operation control means for giving a control start command to allow the molten steel level adjustment means to allow the original level adjustment control, A level control device for a continuous casting facility, comprising: 2. The control operation start time obtaining means, when receiving steel type information at the time of injecting molten steel of a certain steel type, injects the molten steel into the mold and sequentially captures the molten steel level of the molten steel level meter while counting time. Splash determination data is set in advance, and splash determination data is set in advance based on the determination data, and the molten steel level is determined based on the determination result of the splash determination means. Control operation start time registration means for registering the clocking time as a control operation start time together with the steel type data obtained by the steel type related information obtaining means when it is determined that the measurement has reached the measurement stable region of the level meter. The level control device for a continuous casting facility according to claim 1, wherein