JP2014148731A - Operation support system for heat treatment furnace - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable setting of appropriate operation conditions independent of the experience of an operator in operating a heat treatment furnace.SOLUTION: An operation support system 10 for a heat treatment furnace 1 is for supporting manual modification work in modifying conditions set for the heat treatment furnace 1 for heat-treating a to-be-heat-treated material (target material) and is provided with a display which displays information on the target material which passes through the heat treatment furnace 1 and/or the inside of the heat treatment furnace 1. The information displayed on the display includes at least one of the temperature of the target material, the carrying speed of the target material and the temperature of the inside of the heat treatment furnace 1.

Description

  The present invention relates to an operation support system that supports a change work in a heat treatment furnace such as a continuous annealing furnace (CAL) when changing part or all of the set conditions of the heat treatment furnace based on human judgment.

  Conventionally, in a continuous heat treatment line that continuously performs heat treatment of a thin plate or the like, a strip-like thin plate (hereinafter sometimes referred to as a strip material) is introduced into a heat treatment furnace, and a plurality of hearth rolls provided in the heat treatment furnace To pass through the furnace. The heat treatment furnace is controlled to a predetermined furnace temperature, and heat treatment of the strip material such as annealing is performed when the strip material passes through the heat treatment furnace at a predetermined speed.

In the heat treatment furnace, in order to enable continuous processing, a plurality of coils of different steel types and plate thicknesses are connected by welding to form a single strip material, which is continuously passed through.
Therefore, the operator of the heat treatment furnace not only appropriately controls the furnace temperature and the plate passing speed for the strip material in the middle of the plate passing, but also the furnace temperature for the strip material introduced into the heat treatment furnace next time, It is necessary to appropriately control the sheet passing speed and heat-treat the strip material.

As a technique for smoothly performing such control and heat-treating the preceding strip material and the subsequent strip material under the target processing conditions, there is one disclosed in Patent Document 1, for example.
Patent Document 1 discloses a method of continuously heat-treating a preceding material and a succeeding material having different target processing conditions by a continuous heat treatment furnace in which a material made of a metal strip is continuously transferred. After the leading end of the succeeding material is connected to the trailing end, the heating time for maintaining the material arrival temperature of the preceding material constant is calculated while changing the furnace temperature so as to approach the succeeding material furnace temperature. And calculating a line speed suitable for the heating time, controlling the line speed based on the calculation result, and after the furnace temperature reaches the succeeding material furnace temperature, the preceding material and the following material In the process in which the connection portion with the material passes through the continuous heat treatment furnace, the heating time for maintaining the material arrival temperature of the succeeding material at a constant is calculated, and the line speed that matches the heating time is calculated, Control the line speed based on the calculation result. A step, discloses a sheet temperature control method for continuous heat treatment furnace including.

Japanese Patent Laid-Open No. 10-324924

  However, with regard to the heat treatment furnace, the current situation is that it does not change suddenly even if the furnace temperature is changed. For example, when the strip material currently being heat-treated is processed at a furnace temperature of 800 ° C. and the next strip material has a processing temperature of 750 ° C., it takes a predetermined time to lower the furnace temperature by 50 ° C. In this manner, the occurrence of time in the furnace temperature change of the heat treatment furnace is expressed as “thermal inertia”.

The technique of Patent Document 1 described above is capable of calculating the operating conditions of the next strip material while taking into account the thermal inertia of the heat treatment furnace, but in reality, there are various error factors, such as estimation of the furnace temperature. It is clear from the actual results at the site that it is not possible to accurately calculate the correct operation conditions of the next strip material.
Therefore, the operator often changes a part of the setting conditions based on human judgment in order to adjust the conditions of the next strip material after grasping the current heat treatment state.

Experienced operators can set the furnace temperature and plate feed speed for the current strip material that can be easily transferred to the furnace temperature for the next strip material, taking into account such thermal inertia. It is. However, it is often difficult for an inexperienced operator to change the processing conditions while taking into account the thermal inertia of the heat treatment furnace.
Accordingly, in view of the above problems, the present invention provides a heat treatment furnace operation support system that can set appropriate operation conditions without depending on the degree of experience of the operator when operating the heat treatment furnace. Objective.

In order to achieve the above-described object, the present invention takes the following technical means.
The operation support system for the heat treatment furnace according to the present invention is an operation support system that supports human change work when changing the setting conditions in the heat treatment furnace for heat-treating the heat-treated material, and the operation support system includes: An indicator that can be confirmed by an operator is provided, and the indicator is configured to display information on a heat treatment furnace and / or information on a material to be heat-treated passing through the heat treatment furnace.

As the information displayed on the indicator, the actual value obtained from the heat treatment furnace in operation and the predicted value calculated from the numerical model are adopted, and the indicator displays both the actual value and the predicted value. It is preferable to be configured to do so.
It is preferable that the information displayed on the display includes at least one of the temperature of the material to be heat treated, the conveyance speed of the material to be heat treated, and the furnace temperature of the heat treatment furnace.

It is preferable that the information displayed on the display includes a temperature deviation from the target temperature of the material to be heat treated.
It is preferable that the information displayed on the display includes the in-furnace temperature of the heat treatment furnace obtained from past operation results.
It is preferable that the information displayed on the indicator includes a distribution of the furnace temperature of the heat treatment furnace obtained from past operation results.

It is preferable that the indicator displays a current furnace temperature on the furnace temperature distribution.
In calculating the furnace temperature of the heat treatment furnace and the temperature of the material to be heat treated, it is preferable to use a numerical model.

  According to the heat treatment furnace operation support system of the present invention, when operating the heat treatment furnace, it is possible to set appropriate operation conditions without being influenced by the degree of experience of the operator.

The conceptual diagram of the operation support system of a heat treatment furnace is shown. It is the figure which showed a part of heat processing furnace typically. It is the figure which showed an example of the screen of a support monitor. It is the figure which showed the method of calculating the operation performance of a furnace temperature past.

Embodiments of a heat treatment furnace operation support system according to the present invention will be described below with reference to the drawings. FIG. 1 is a schematic diagram showing an operation support system of this embodiment and a heat treatment furnace 1 provided with the operation support system.
As shown in FIGS. 1 and 2, the heat treatment furnace 1 is a continuous annealing furnace (CAL) for annealing the introduced thin steel plate (strip material) 2. The heat treatment furnace 1 is composed of three independent portions of a pre-tropical zone 3, a heating zone 4, and a soaking zone 5 from the upstream side. In each of the bands 3 to 5, a plurality of hearth rolls 6 are provided, and the strip material 2 is bridged between the hearth rolls 6 and conveyed in the furnace. A plurality of radiant tubes (not shown) are positioned in the furnace, and the temperature in the furnace is increased by radiant heat from the radiant tubes.

In addition, an exit side thermometer 7 for measuring the temperature of the strip material 2 is provided on the exit side of the pre-tropical zone 3, the heating zone 4, and the soaking zone 5.
When operating the heat treatment furnace 1 described above, the operator M is required to set the temperature (furnace temperature) in the heat treatment furnace 1 so that annealing of the strip material 2 proceeds efficiently and has the desired metal structure and mechanical properties. And operating conditions such as the conveying speed of the strip material 2 are controlled.

  Specifically, in order to enable continuous processing in the heat treatment furnace 1, first, a plurality of different steel grades and plate thickness coils are connected by welding to form a single strip material 2 and are continuously passed through. Yes. Therefore, the operator M managing the heat treatment furnace 1 introduces the heat treatment furnace 1 into the heat treatment furnace 1 as well as appropriately controlling the furnace temperature and the conveying speed for the strip material 2 (preceding strip material) halfway through the plate. The strip material 2 (following strip material) also needs to be heat-treated by appropriately controlling the furnace temperature and the conveying speed.

  The operator M determines the operating conditions (furnace temperature, conveyance speed, etc.) when the TV value (product of the plate thickness T and the conveyance plate speed V) and the target plate temperature change between the preceding strip material and the subsequent strip material. To change. For example, when the TV value changes, it is necessary to raise or lower the temperature of the heat treatment furnace 1. Therefore, after estimating the amount of change in the plate temperature of the heating zone 4, When the temperature remains at this temperature, it is checked whether or not the plate temperature falls within the control range, and if necessary, the operation conditions are changed. On the other hand, the performance of the heat treatment furnace 1 changes from day to day, and it is indispensable to change the operating conditions from this point.

The operation conditions of such a heat treatment furnace 1 can be set by an experienced operator M so that a desired plate temperature can be secured based on various past experiences. However, in the case of an inexperienced operator M, it can be considered that it is difficult to operate the heat treatment furnace 1 accurately.
Therefore, the operation support system of the present embodiment is configured to present the information of the heat treatment furnace 1 so that appropriate operation conditions can be set regardless of the degree of experience of the operator M. ing.

Hereinafter, details of the operation support system for the heat treatment furnace 1 of the present embodiment will be described.
The operation support system 10 includes a display (support monitor) 11 that can display at least one of information on the heat treatment furnace 1 and information on the strip material 2 (material to be heat treated).
The support monitor 11 includes a liquid crystal monitor and a CRT monitor, and is installed in the control room. The operator M can always view the support monitor 11. A computer 12 is connected to the support monitor 11, and the computer 12 calculates part or all of the information displayed on the support monitor 11. An operation condition (operation result value) is input to the computer 12, and the computer 12 can calculate information to be displayed on the support monitor 11 using the operation result value as an input value. A numerical model (heat treatment furnace model) is provided.

Specifically, the computer 12 includes an arithmetic device and a storage device inside, and includes an input device for fetching instructions to the computer 12 and signals from the outside, and an output device for displaying the calculation result. ing.
The heat treatment furnace model is programmed and stored in a storage device configured by a hard disk, and this model is calculated by an arithmetic device configured by an MPU or the like. For the calculation, the actual values (the actual values such as the temperature of the strip material, the conveyance speed, the state of the radiant tube) obtained from the operating soaking furnace are input via an input device composed of an AD conversion board. And adopted as the condition value of the heat treatment furnace model. The actual value may be directly input by an input device such as a keyboard.

The result (predicted value of the heat treatment furnace model) calculated by the calculation device is recorded in the storage device and displayed on the output device, that is, the support monitor 11. The actual value of the heat treatment furnace model input through the input device is also displayed on the support monitor 11 at the same time.
In the case of this embodiment, the heat treatment furnace model is a numerical model based on the equation (1) obtained from the heat transfer model.

  The computer 12 can calculate a predicted value of the plate temperature of the strip material 2 and a plate temperature deviation from the target temperature using a heat treatment furnace model provided inside, and the calculated predicted plate temperature and plate temperature. The deviation is output to the support monitor 11. In addition, since the plate temperature is different at the front end portion, midway portion, and tail end portion even in the same strip material 2, the computer 12 calculates the plate temperature deviation at each of the front end portion, midway portion, and tail end portion.

FIG. 3 shows an example of a screen display of the support monitor 11 of the present embodiment.
As shown in FIG. 3, the screen of the support monitor 11 is divided into upper and lower parts, and information on the preceding strip material and the subsequent strip material is mainly displayed on the upper part (plate temperature monitor). Specifically, in the upper portion, in the preceding strip material and the following strip material, the remaining time until each strip material 2 enters the soaking zone 5 (time until the soaking zone 5 passes) and the current operation When each strip member 2 enters the soaking zone with the condition maintained, the plate temperature of each strip member 2 is displayed in a graph. Here, the plate temperature shown in a graph is a deviation amount between the predicted temperature and the target temperature when entering the soaking zone as will be described later.

  In the upper part, the strip material 2 corresponding to the coils A to C indicates the strip material 2 in the heating zone 4. The strip material 2 corresponding to the coil D and the coil E indicates the strip material 2 existing in the pre-tropical zone 3. In the upper portion, the type and thickness of the strip material 2 (the preceding strip material and the subsequent strip material) conveyed in the furnace may be indicated at the position indicated by L.

Two graphs (graph U) are shown on the lower side indicating the type and thickness of each strip material 2. This graph U shows the plate temperature deviation (deviation between the target plate temperature and the plate temperature calculated from the heat treatment furnace model) of the strip material 2.
Of the two graphs U, the right graph shows the plate temperature deviation at the front end of the strip material 2, and the left graph shows the plate temperature deviation at the tail end. In the wavy line indicated by N (line N), the center line indicates the target temperature line (the line temperature deviation is zero), the upper line indicates the upper limit value, and the lower line indicates the lower limit value. That is, the management range in the temperature of the strip material 2 is shown by the line N.

The portion indicated by D indicates the transport speed of the strip material 2, the dark colored bar indicates the current transport speed, and when the operator M gives an instruction to change the transport speed, the bar indicated by D The length changes according to the conveyance speed.
Therefore, in the upper part of the screen of the support monitor 11, various information regarding the strip material 2 such as the type of strip material 2, the plate thickness, the plate temperature deviation of the strip material 2, and the conveyance speed are displayed.

  When the operator M changes the operating conditions of the heat treatment furnace 1 (the state of the radiant tube, the conveying speed of the strip material 2), the changed operating conditions, for example, the actual temperature value at the outlet side thermometer 7 are stored in the computer. 12, the predicted value of the plate temperature is immediately calculated using the heat treatment furnace model, and a new graph U based on the information is displayed. By this process, the screen is changed as needed, and the graph U is updated to the latest value every moment.

Therefore, the operator M only has to change the operating conditions of the heat treatment furnace 1 so that the graph U displayed on the support monitor 11 falls within the range indicated by the line N (within the management range). Appropriate operating conditions can be set without being affected by
When the processing temperature of the subsequent strip material is lower than the processing temperature of the preceding strip material, in order to cope with the thermal inertia of the heat treatment furnace 1, the operator M positions the graph U of the preceding strip material on the lower limit side of the management region. As such, the setting may be made while viewing the support monitor 11. By doing so, when the subsequent strip material enters the furnace, the temperature can be brought to the set value as quickly as possible.

Such an operation can be performed only by his / her own judgment if it is an experienced operator M. However, even if the operator M is inexperienced, the operation support system 10 of the present invention is used. Thus, it is possible to perform the heat treatment furnace 1 control equivalent to the experienced operator M.
Information on the heat treatment furnace 1 is mainly shown in the lower part of the screen of the support monitor 11 (furnace operation monitor). The part of Q shows the temperature prediction distribution (histogram) of the pretropical zone 3 based on the past operation results. The temperature distribution of the pretropical zone 3 for each strip material 2 is shown so that the temperature distribution of the pretropical zone 3 when each strip material 2 (coil A to coil E) is processed in the past operation can be understood. ing. The past operation results include, for example, a case where each strip material 2 is processed while changing the conveying speed and a case where each strip material 2 is processed while changing the furnace temperature. Since the conditions vary, it is assumed that the temperature prediction distribution of the pretropical zone 3 shown in the Q part is processed under the current operating conditions (assuming that the operation was performed under the same conditions), and the temperature of the pretropical zone 3 at that time Predictive distribution.

On the screen of the support monitor 11, the line q1 shown on the temperature prediction distribution of the pre-tropical zone 3 is the furnace temperature (actual value) of the pre-tropical zone 3 at the present time, It can be verified whether it corresponds to the position. That is, the current furnace temperature is displayed on the temperature prediction distribution of the furnace temperature calculated from the past operation results.
Further, in the lower part of the screen of the support monitor 11, the part R represents the furnace temperature of the pre-tropical zone 3 with specific numerical values. This temperature value is the mode value of the temperature prediction distribution indicated by Q.

  The portion S represents the temperature prediction distribution of the heating zone 4, and the portion T represents the temperature value of the furnace temperature of the heating zone 4. A line q2 indicating the furnace temperature of the heating zone 4 at the present time is also shown on the temperature prediction distribution of the heating zone 4. The temperature predicted distribution of the heating zone 4 in the portion S is obtained by the same method as the pre-tropical zone 3 shown in the Q portion, and the temperature value of the heating zone 4 in the portion T is also the same as the pre-tropical zone 3. It was also stopped by the method.

  Accordingly, in the lower part of the screen of the support monitor 11, information on the heat treatment furnace 1 (temperature prediction distribution of the pretropical zone 3 and the heating zone 4, temperature values of the pretropical zone 3 and the heating zone 4 obtained from this temperature prediction distribution (maximum Frequency), pre-tropical zone 3 and current furnace temperature of heating zone 4) are displayed. That is, the information displayed in the lower part of the screen of the support monitor 11 includes the furnace temperature (in-furnace temperature) of the heat treatment furnace 1 when the strip material 2 in the past operation results is processed, and the temperature of the furnace temperature. Distribution (temperature prediction distribution) is included.

That is, both the predicted value based on the numerical model and the actual value during operation are displayed on the support monitor 11, and the operator M determines the degree of coincidence between the predicted value and the actual value and the correlation between the predicted value and the actual value. It is also possible to change the operating conditions while taking into account the strength of the product.
Various methods can be adopted as an estimation method for obtaining the temperature prediction distribution, but in the present embodiment, the method shown in FIG. 4 is used.

As shown in FIG. 4, first, the distance (degree of difference) between the past operation condition and the current condition condition is calculated using equation (2) (S1).
Thereafter, based on the calculated distance, the similarity is calculated using Equation (3) (S2). That is, the similarity calculation means provided in the computer 12 obtains the difference between the past operation condition and the current operation condition, and obtains the similarity calculated from the obtained difference. The relationship between the similarity and the distance is, for example, as shown in FIG.

  By applying the obtained similarity to the past temperature performance of the strip material 2 by the frequency distribution calculation means provided in the computer 12 as shown in the equation (4), the strip material as shown in FIG. 2 is calculated (S3).

  By using the operation support system 10 and displaying information on the heat treatment furnace 1 and information on the material to be heat treated (strip material 2) on the support monitor 11, an appropriate heat treatment furnace 1 can be obtained regardless of the degree of experience of the operator M. The operating conditions can be set. In the above-described embodiment, both the information on the heat treatment furnace 1 and the information on the strip material 2 are displayed on the support monitor 11, but either the information on the heat treatment furnace 1 or the information on the strip material 2 is supported. It may be displayed on the monitor 11.

As mentioned above, it should be thought that embodiment disclosed this time is an illustration and restrictive at no points. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.
For example, the support monitor 11 may display information regarding other heat treatment furnaces 1. Moreover, although the support monitor 11 which appeals visually is illustrated as a display which shows various information to the operator M, you may employ | adopt the apparatus which conveys information with an audio | voice to the operator M as a display.

DESCRIPTION OF SYMBOLS 1 Heat processing furnace 2 Strip material 3 Pre-tropical 4 Heating zone 5 Soaking zone 6 Hearth roll 7 Outside thermometer 10 Operation support system 11 Support monitor 12 Computer

Claims (8)

An operation support system that supports human change work when changing the setting conditions in a heat treatment furnace for heat treating a material to be heat treated,
The operation support system has a display that can be confirmed by an operator,
The said heat indicator is comprised so that the information of the heat processing furnace and / or the information of the heat-treated material which passes the inside of a heat processing furnace may be displayed, The operation support system of the heat processing furnace characterized by the above-mentioned. As the information displayed on the indicator, adopt the actual value obtained from the heat treatment furnace in operation and the predicted value calculated from the numerical model,
2. The heat treatment furnace operation support system according to claim 1, wherein the indicator is configured to display both the actual value and the predicted value.   The information displayed on the display includes at least one of a temperature of the material to be heat treated, a conveyance speed of the material to be heat treated, and a furnace temperature of the heat treatment furnace. Heat treatment furnace operation support system.   3. The heat treatment furnace operation support system according to claim 1, wherein the information displayed on the display includes a temperature deviation from a target temperature of the material to be heat treated.   3. The heat treatment furnace operation support system according to claim 1 or 2, wherein the information displayed on the display includes a furnace temperature of the heat treatment furnace obtained from past operation results.   6. The operation support system for a heat treatment furnace according to claim 5, wherein the information displayed on the display includes a distribution of the furnace temperature of the heat treatment furnace obtained from past operation results.   The heat treatment furnace operation support system according to claim 6, wherein the indicator displays a current furnace temperature on the furnace temperature distribution.   8. The heat treatment furnace operation support system according to claim 1, wherein a numerical model is used in calculating the furnace temperature of the heat treatment furnace and the temperature of the material to be heat treated. 9.