JP3247216B2 - Automatic pouring of molten copper from refining furnace - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention generally relates to a pouring method for pouring molten copper from a refining furnace into a mold via a basin. The present invention relates to an automatic pouring method, characterized in that the tilting speed of a refining furnace is controlled by fuzzy control so that the amount of molten copper poured into a reservoir is kept constant.

[0002]

2. Description of the Related Art Conventionally, an anode for copper electrolysis has been cast by a Walker method in which molten copper from a refining furnace is poured into a horizontally arranged mold at a constant rate.

Briefly referring to FIG. 5, in order to pour a fixed amount into a mold M having a predetermined shape, first, the refining furnace 2 is tilted, and the molten copper in the refining furnace 2 is 6 is poured into a basin 8 having an inner volume of about 10 times the inner volume of the mold,
The storage pan 8 is tilted so that the molten copper 6 in the storage pan 8 has a capacity of 2
The molten metal is poured into two weighing pans 10 having about twice the internal volume, and finally a certain amount is poured from the weighing pan 10 to the two molds M carried and carried on the turntable 12.

[0004] A weighing device 14,
16 are installed. For example, the discharge amount of the storage pan 8 is 65
It is about 0Kg, and each measuring pan 10 discharges 325K
It is designed to be about g.

[0005] In the above configuration, the furnace tilting of the refining furnace 2 is performed by the tilting motor 20 including a high-speed motor and a low-speed motor. Basically, the low-speed motor is used for casting, and the high-speed motor is used for casting. Used for tilting operation other than at the time. For example, a high-speed motor can perform forward rotation and reverse rotation at a furnace rotation speed of up to 310 × 10 ⁻³ rpm, for example, and a low-speed motor can only rotate forward at a furnace rotation speed of up to 1.43 × 10 ⁻³ rpm, for example. Rotation is possible.

Since the molten metal flows continuously from the refining furnace 2, the weight of the storage pan 8 gradually rises as shown in FIG. 6 and rapidly drops when the molten metal is poured into the measuring pan. The change is repeating. The sampling of the weight data takes in the point P which becomes the peak in the figure.

Further, before the pouring amount into the measuring pan 10 reaches the predetermined value, the storage pan 8 reverses the tilting direction and starts a return operation.
Immediately after the start of the return operation, the molten copper 6 in the storage pan 8 is still poured into the measuring pan 10, and the flow of the molten copper 6 into the measuring pan 10 after the return operation is referred to as "dripping".

When the amount of hot water in the basin 8 is large or small, the amount of dripping is different. When the amount of hot water is small, the amount of dripping is small. When the amount of hot water is large, the amount of dripping increases. .

The measuring pan 10 also has the same phenomenon as the storage pan 8, and the amount of droop varies depending on the amount of hot water (weight) immediately before the measuring pan 10 is discharged.

Therefore, the variation in the amount of molten metal poured into the mold M is caused by the variation in the dripping amount, and as a result, causes the variation in the anode weight.

For this reason, in order to carry out stable anode casting by the Walker method, first, it is necessary to keep the weight of the reservoir 8 constant, that is, to control the tilting speed v of the refining furnace 2. The most important is empirically known.

At present, this adjustment is performed by the operator operating the power control panel 24 while watching the weight of the molten copper in the storage pan 8 and the measuring pan 10 (the weight display 22) displayed on the weight display 22 or the like. 20 is controlled by manually adjusting the tilting speed v of the refining furnace 2 upstream of the storage pan 8.

[0013] However, there is an individual difference in the skills of the operators, and it is difficult to standardize the adjustment method, which disturbs stable operation.

Although the automatic pouring method has been attempted, the conventional automatic pouring method is to program the tilting speed v of the refining furnace 2 according to the pouring amount, and to tilt the refining furnace 2 at a speed along the same.
In addition, correction was made based on the deviation from the actual weight.

However, in such an automatic pouring method, even at the same tilting speed, a change in the size of the pouring gate of the refining furnace 2 or a change in the pouring amount that changes depending on the temperature of the molten copper 6 in the refining furnace 2 causes. When the tilt pattern is stored in a memory, the deviation increases and it is difficult to stabilize the weight of the molten copper in the reservoir 8.

As described above, according to the prior art, the weight of the anode is not stable as a result, so that the thickness of the anode also varies.
It also causes trouble in the milling process. In addition, it also causes a short circuit at the time of electrolysis, resulting in deterioration of current efficiency.

Accordingly, an object of the present invention is to provide a method for automatically pouring molten copper from a refining furnace, which makes it possible to reduce the variation in the thickness of the anode to be cast and to enable uniform casting of the anode. is there.

[0018]

The above object is achieved by the method for automatically pouring molten copper from a refining furnace according to the present invention. In summary, the present invention continuously pours the molten copper of the refining furnace into a storage pan, intermittently pours the molten copper of the poured storage pan into a measuring pan,
Further, in the method of pouring molten copper into the casting mold from the measuring pan, the peak value of the weight of the storage pan that increases and decreases over time is stored, and a deviation value from a target value is stored based on the stored data. Is calculated by comparing the instantaneous value which is the weight peak value before pouring into the ladle and the past, and a fuzzy inference is made from these instantaneous values and the weight fluctuation tendency value indicating whether the tendency is upward or downward. A method of automatically pouring molten copper from a refining furnace, wherein an appropriate tilting speed is calculated based on the result, and the tilting speed of the refining furnace is controlled based on the calculation result.

[0019]

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The method for automatically pouring molten copper from a refining furnace according to the present invention will be described in more detail with reference to the drawings.

In the present invention, in order to stabilize the weight immediately before the discharge of the pan near the target value, the weight immediately before the discharge of the pan is stored, and the instantaneous value and the weight change tendency are stored based on the trend data. , And fuzzy inference from each,
An appropriate tilting speed is derived and fed back to the tilting speed of the refining furnace to obtain an appropriate tilting speed.

FIG. 1 schematically illustrates an automatic pouring system constructed in accordance with the present invention. According to this system,
The molten copper 6 in the refining furnace 2 is poured into the reservoir 8 having an inner volume of about 10 times the inner volume of the mold via the gutter 4 by tilting the refining furnace 2. The storage pan 8 is tilted and the storage pan 8
The molten copper 6 in the container is poured into two measuring pans 10 having usually twice the internal volume of the casting mold.
From 0, a certain amount of molten metal is poured into the two molds M carried and conveyed on the turntable 12.

Here, the storage pan 8 is provided with a load cell 14 for weighing.
, The weight is measured, and the signal is transmitted to the weighing unit 18 and converted into a weight signal. This weight signal is input to the storage circuit 102 of the fuzzy control unit 100, and in this embodiment, data of up to 15 times is stored. The sampling of the weight data is set to a peak value.

Further, according to the present invention, a deviation value (d ₁ ) from the set value of the pot weight immediately before the refining furnace tilting operation and a fluctuation of the pot weight are calculated by the arithmetic circuit 103 based on the data of the storage circuit 102. The trend values (d ₂ ) are calculated and each is subjected to fuzzy inference.

A speed command signal is output based on the calculation result, and the drive of the refining furnace tilting motor 20 is controlled via the power controller 24.

Next, an embodiment will be described in more detail with respect to fuzzy inference according to the present invention.

Embodiment 1 In this embodiment, an instantaneous value in fuzzy inference, that is, a deviation value (d ₁ ), is given by d ₁ = (weight target value) − (weight data immediately before), and It is a deviation from the set value of the pot weight immediately before the rolling operation, and the fluctuation tendency value (d ₂ ) is d ₂ = (average value of data from immediately before to 5 times) − (6 times to 10 times) The average value of the previous data) is calculated, and how much the fluctuation tendency of the weight of the storage pot is increasing or decreasing is calculated, and is set as the fluctuation tendency of the weight.

The deviation value (d ₁ ) and the fluctuation tendency value (d ₂ )
Is used as a condition part membership function, a furnace tilting speed manipulated variable v (conclusion part membership function) is inferred.

In order to obtain the inference data of the fuzzy control, hearing with a good operator and organizing the results resulted in a condition part membership function and a conclusion part membership function as shown in FIG. These functions are obtained by replacing the qualitative feeling intuitively felt by the operator with numerical values and converting them into functions.

Next, the results obtained by interviewing the operator with the production rules in the same manner are summarized in Table 1.

[0031]

[Table 1]

Terminology Label name Meaning NL (Negative Large) Negative large NM (Negative Medium) Negative medium NS (Negative Small) Negative small ZR (Approximately Zero) Approximately zero PS (Positive) Small) Positive Midum Small in the positive direction Medium in the positive direction PL (Positive Larga) Large in the positive direction

The procedure of the fuzzy inference based on the membership function and the production rules will be described. As shown in FIG. 3, first, a deviation value (d ₁ ) and a fluctuation tendency value (d ₂ ) are input to an arithmetic circuit. You. The arithmetic circuit calculates the grade of the condition part membership function in each production rule, and takes the minimum of the condition part membership function as the grade of the conclusion part membership function. Next, the OR of the conclusion part membership function is calculated, the center of gravity is obtained, and the tilt operation amount v of the refining furnace is determined.

For example, when the casting is performed while tilting at a low speed, the refining furnace tilts when the weight change tendency is about 25 kg when the pot weight is 125 kg heavier than the target value. According to the present invention, a fuzzy inference was made on how much the rolling speed should be adjusted with respect to the current speed. That is, it was inferred that the weight deviation (d ₁ ) = 125 kg and the weight fluctuation tendency (d ₂ ) = − 25 kg. FIG. 4 shows the result of the logical sum of the conclusion part membership functions.

In FIG. 4, the manipulated variable (v) obtained from the center of gravity was -73 rpm. The values obtained as a result of the inference were substantially the same as the operations actually performed by the operator.

Embodiment 2 In this embodiment, in order to more effectively cancel outliers peculiar to a casserole, data acquisition is performed once each time from the viewpoint of emphasizing tendency on both the membership function and the production rule. Changed from instantaneous value acquisition to average value acquisition for the previous two times. That is, it was considered that an average deviation could be taken and an abnormal value could be canceled by this. In order to improve the responsiveness to the deviation, the difference of the average of 5 times is calculated as the difference of the average of 2 times (weight average of 1 or 2 times before)-(10 to 1 times before).
(Average once). Thus, it was considered that the responsiveness can be improved by the difference between the two averages. The production rules were also modified as shown in Table 2 to improve the responsiveness of the inference results and to avoid performing unnecessary operations if they were within the allowable range.

That is, in this embodiment, the deviation value (d ₁ ) and the fluctuation tendency value (d ₂ ) are given by d ₁ = {(weight immediately before current discharge) + (weight immediately before the previous discharge)}. ÷ 2 d ₂ = ｛(weight immediately before current discharge) + (weight immediately before previous discharge) 排出 2-｛(weight immediately before discharge 10 times) + (weight immediately before discharge 11 times) (Weight)｝ ÷ 2.

[0038]

[Table 2]

As for the operation results, better controllability than expected was obtained.

[0040]

As described above, according to the present invention, the molten copper of the refining furnace is continuously poured into the storage pan, and the molten copper of the poured storage pan is intermittently poured into the measuring pan. In the method of pouring molten copper into the casting mold from the measuring pan, the peak value of the weight of the storage pan that increases and decreases over time is stored, and based on the stored data, the deviation value from the target value is calculated. Calculate the weight fluctuation trend value by comparing the instantaneous value and the past weight peak value before pouring in the ladle, and perform fuzzy inference from these instantaneous values and the weight fluctuation tendency value indicating whether it is increasing or decreasing. Since the tilting speed is calculated and the tilting speed of the refining furnace is controlled based on the calculation result, the variation in the thickness of the anode to be cast can be reduced and a uniform anode can be cast. Therefore, the anode manufactured in the present invention is:
A handling step, a milling step, and the like as a post-step are not required, and a problem such as a short-circuit of an electrode in an electrolytic factory, which is the next step, can be solved.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an automatic pouring system for performing a method for automatically pouring molten copper from a refining furnace according to the present invention.

FIG. 2 is a diagram illustrating an example of a membership function.

FIG. 3 is an explanatory diagram showing a procedure of fuzzy inference.

FIG. 4 is an explanatory diagram showing an example of a logical sum obtained by fuzzy inference.

FIG. 5 is a schematic configuration diagram of an automatic pouring system for performing a conventional method for automatically pouring molten copper from a refining furnace.

FIG. 6 is a diagram showing a change in weight of a storage pan.

[Explanation of symbols]

 2 Refining furnace 8 Reservoir 10 Measuring pan 20 Electric motor for tilting 100 Fuzzy controller

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification code FI F27D 3/14 F27D 3/14 Z G05B 13/02 G05B 13/02 N (56) References JP-A-57-62855 (JP, A) JP-A-4-46665 (JP, A) JP-A-6-39532 (JP, A) JP-A-5-8025 (JP, A) JP-A-57-100845 (JP, A) JP-A-52 -10827 (JP, A) JP-A-51-18936 (JP, A) JP-B-55-32461 (JP, B2) JP-B-49-41459 (JP, Y1) (58) Fields investigated (Int. . ^7, DB name) B22D 39/04 B22D 5/00 B22D 25/04 F27B 3/06 F27B 3/28 F27D 3/14 G05B 13/02

Claims (1)

(57) [Claims] 1. The molten copper of a refining furnace is continuously poured into a reservoir,
The molten copper in the poured pot is intermittently poured into the measuring pan, and further, in the method of pouring molten copper from the measuring pot to the mold, the weight of the pool that increases or decreases over time is reduced. The peak value is stored, and based on the stored data, an instantaneous value that is a deviation value from the target value is calculated, and a weight fluctuation tendency value is calculated by comparing the instantaneous value, which is a weight peak value before the pouring of the casserole, and these instantaneous values are calculated. And calculating a proper tilting speed by fuzzy inference from the weight fluctuation tendency value of whether the trend is upward or downward, and controlling the tilting speed of the refining furnace based on the result. Automatic pouring of molten copper.