JP6396248B2 - Reservation material application method and reservation material application device - Google Patents

Description

  The present invention relates to a method for applying a retaining material and a device for applying a retaining material when molten material or cast slabs are produced in a steel mill.

Conventionally, in steel mills, product materials (for example, thin steel plates) are manufactured through a steelmaking process, a steelmaking process (both are collectively referred to as a refining process), a casting process, and a rolling process.
The refining process (especially the steel making process) generates molten steel by decarburizing the molten iron supplied from the blast furnace in the converter, and the generated molten steel is transported to the secondary refining equipment and subjected to secondary refining. The components of the molten steel are adjusted in the equipment. The molten steel after the component adjustment is transported to a continuous casting facility which is a casting process, and becomes a slab (rolled intermediate product) having a predetermined length and size in the continuous casting facility. The slab manufactured in the casting process is rolled into a product material in the rolling process.

  Each process in such a steelworks is disclosed in detail in Non-Patent Document 1 and the like.

Introduction to steel process engineering, JFE 21st Century Foundation, http://www.jfe-21st-cf.or.jp/jpn/index2.html

In the case of manufacturing a product such as a steel material through the steps disclosed in Non-Patent Document 1, it is rare but troubles described below have been raised as actual results in the field.
That is, as shown in FIG. 4, when a product material such as a thin steel plate is manufactured, it is performed based on a steel sheet specification provided by a user (customer). This steel sheet specification describes the required quality of the steel sheet, for example, the mechanical test characteristics of the steel sheet (specification values such as a tensile test, a bending test, and an impact test).

In the steelworks, various types of steel types are lined up based on past production results, and the “steel type” that satisfies the mechanical test characteristics (specification values) desired by the user is determined and determined by the steel type determination unit 20. Production of molten steel of the selected steel type will be performed.
For example, it is assumed that a high-strength steel sheet is received from the user, and the specification of the high-strength steel sheet states that a high-strength steel sheet having a tensile strength of 800 MPa or more is required. In this case, in the steelworks, the steel type that satisfies the quality required by the user is determined based on the specification provided by the designer of the steel type. For example, assume that the steel type M is determined.

When the steel type M is determined, in the refining process, the components of the molten steel are adjusted so as to fall between the upper limit value and the lower limit value of the components (Mn, C, Mo, Cr, P, etc.) in the determined steel type M. Is done. Moreover, also about the slab manufactured through the casting process, the component of the said slab must be settled between the upper limit value and the lower limit value of the component in the steel type M.
However, in practice, the components of the molten steel after refining may slightly deviate from the component range in the steel type M due to troubles in the refining process, for example, secondary refining. Moreover, in the casting process, as the production of the slab proceeds, components such as Mn and Cr existing outside are added to the molten steel or slab to increase the ratio of the components, or the Mn and Cr in the slab are increased. And the like may go out and the ratio of the components may be lowered. At this time, although rarely, the component value (actual value) of the slab deviates from between the upper limit value and lower limit value of the component in the determined steel type M.

Thus, when the performance value of the component of the manufactured molten steel or slab deviates from between the upper limit value and the lower limit value of the component in the steel type M, the material (slab) is referred to as a retaining material. This molten steel or slab is taken to another order. The determination of such a conversion measure of molten steel or slab must be made with great consideration even by an experienced operator, and it takes time and days. In addition, in the molten steel, when a component detachment is detected, a measure such as performing secondary refining may be taken. It will increase. The technique corresponding to such a measure at the time of non-stationary state has not been established and is not disclosed in Non-Patent Document 1.

  Therefore, in view of the above-mentioned problems, the present invention provides a retaining material application method and a retaining material that can accurately and quickly determine the countermeasures to be taken when molten steel or slab becomes a retaining material in an ironworks. An object is to provide an appropriation device.

In order to solve the above problems, the present invention takes the following technical means.
The retentive material application method of the present invention includes a refining process for refining molten iron to produce molten steel, a casting process for producing a slab from the molten steel produced in the refining process, and a slab cast in the casting process In the method of appropriating reserve material implemented at an ironworks having a rolling process for rolling product material from the steel, the steel grade that satisfies the mechanical test characteristics of the target slab based on the steel sheet specifications provided by the user the steel grade determination step of determining from among the steels produced in the past, the component determining step of determining an upper limit value and the lower limit value of the component to meet the mechanical test properties of the slab to the target, determined in the component determination step Component value holding step for holding the upper limit value and the lower limit value of the obtained component for each mechanical test characteristic of the target slab, and the molten steel produced in the refining step or the slab component produced in the casting step Analyze the actual value of The actual value of the component of the molten steel or slab analyzed in the analysis step and the component analysis step is compared with the upper limit value and lower limit value of the component held in the component value holding step, and the result of the comparison Even if the actual value of the molten steel or slab component deviates from the upper limit value and lower limit value of the component in the steel type determined in the steel type determining step, the actual value of the molten steel or slab component is A continuation determining step for determining that the molten steel or slab is to be sent to a lower step when the component value is held between the upper limit value and the lower limit value of the component held in the component value holding step. And

Preferably, the component value holding step holds the upper limit value and the lower limit value of the component determined in the component determination step and the mechanical test characteristics of the target slab as past actual values for each steel type. Good.
Preferably, from the component value holding step, for each steel type, the upper limit value and lower limit value of the component determined in the component determination step and the mechanical test characteristics of the target slab are read, based on the read value, A component / characteristic analysis step for obtaining a correlation between an upper limit value and a lower limit value of the component determined in the component determination step and a mechanical test characteristic of the target slab, and using the correlation, the molten steel or casting A property estimation step for estimating an estimated value of the mechanical test property of the piece, and in the continuation determination step, even if the upper limit value and the lower limit value of the components in the steel type determined in the steel type determination step are deviated, When the estimated value of the mechanical test characteristic of the molten steel or slab estimated in the characteristic estimation step falls within the range of the target mechanical test characteristic of the slab, the molten steel manufactured in the refining step or the Manufactured in the casting process The cast slab was may be determined to send down process.

Preferably, in the component value holding step, steel types having similar mechanical test characteristics are grouped and held for each item of the mechanical test.
Preferably, from the component value holding step, mechanical test characteristics of steel types having similar grouped mechanical test characteristics are read out, and an estimated value of the mechanical test characteristics of the molten steel or slab is calculated using the read values. And in the continuation determining step, the molten steel or cast estimated in the property estimating step is deviated from the upper limit value and the lower limit value of the components in the steel type determined in the steel type determining step. When the estimated value of the mechanical test characteristic of the piece falls within the range of the mechanical test characteristic of the target slab, the molten steel produced in the refining process or the slab produced in the casting process is transferred to the lower process. You may decide to send.

Preferably, in the component value holding step, a steel type having similar mechanical test characteristics and a steel type having mechanical test characteristics lower than the similar steel types are grouped and held for each mechanical test characteristic.
Preferably, from the component value holding step, the steel type having the similar grouped mechanical test property and the mechanical test property of the steel type having the mechanical test property lower than the similar steel type are read out, and the read value is used. A property estimation step for estimating an estimated value of the mechanical test property of the molten steel or slab, and the continuation determination step deviates from the upper limit value and the lower limit value of the components in the steel type determined in the steel type determination step. Even if the estimated value of the mechanical test property of the molten steel or slab estimated in the property estimation step falls within the range of the target mechanical test property of the slab, it is manufactured in the refining step. The molten steel or the slab produced in the casting process may be determined to be sent to the lower process.

The reserve material applicator of the present invention includes a refining process for refining molten iron to produce molten steel, a casting process for producing a slab from the molten steel produced in the refining process, and a slab cast in the casting process Steel material that satisfies the mechanical test characteristics of the target slab , based on the specifications of the steel sheet provided by the user , in the reserve material applicator that is implemented at the ironworks having the rolling process of rolling the product material from Determined by the steel type determination unit that determines the steel type manufactured in the past, the component determination unit that determines the upper limit value and the lower limit value of the component that satisfies the mechanical test characteristics of the target slab, and the component determination unit Component value holding part for holding the upper limit value and the lower limit value of the obtained component for each mechanical test characteristic of the target slab, and the molten steel produced in the refining process or the component of the slab produced in the casting process Component analysis unit that analyzes actual values of The actual value of the component of the molten steel or slab analyzed by the component analysis unit is compared with the upper limit value and the lower limit value of the component held by the component value holding unit, and as a result of the comparison, the molten steel Or even if the actual value of the slab component deviates from the upper limit value and the lower limit value of the component in the steel type determined by the steel type determination unit, the actual value of the molten steel or slab component remains the component value A continuation deciding unit for deciding to send the molten steel or slab to a lower process when it is between the upper limit value and the lower limit value of the components held in the part.

  According to the reservation material appropriation method and the reservation material applicator according to the present invention, even if a retained material of molten steel or slab is generated in an ironworks, the countermeasure can be determined accurately and quickly.

It is the figure which showed typically 1st Embodiment of the allocation method of the reservation material of this invention. It is the figure which showed typically 2nd Embodiment-4th Embodiment of the allocation method of the reservation material of this invention. It is the graph which showed correlation with the value of the component of the slab manufactured in the past, and the mechanical test characteristic of the slab manufactured in the past. It is the figure which showed the manufacturing method of the conventional product material typically.

DESCRIPTION OF EMBODIMENTS Hereinafter, a first embodiment of a reservation material application method and a reservation material application device according to the present invention will be described with reference to the drawings.
[First Embodiment]
As shown in FIG. 1, the reserve material applicator 1 of the present invention is an apparatus attached to each process in an ironworks.

In steelworks, a steelmaking process for producing molten steel by adjusting the components of the molten iron using a smelting process for producing molten iron from iron ore using a blast furnace, a hot metal pretreatment device, a converter, and a secondary refining device Is provided. The iron making process and the steel making process may be collectively referred to as a refining process 30.
The molten steel produced in the refining process 30 is conveyed to the casting process 31 and becomes a slab W (rolled intermediate product) having a predetermined length and size in the continuous casting apparatus. The slab W manufactured in the casting process 31 is rolled into a product material in the rolling process 32.

As attached to each process in such a steelworks, the reserve material applicator 1 of the present invention is a steel type determination unit 2 that determines a steel type that satisfies the mechanical test characteristics of the target slab W, and is a target. The component determination unit 3 that determines the upper limit value and the lower limit value of the components that satisfy the mechanical test characteristics of the slab W, and the mechanical test of the slab W that uses the upper limit value and lower limit value of the component determined by the component determination unit 3 as targets. The component value holding unit 4 that holds each characteristic, the component analysis unit 5 that analyzes the actual values of the components of the molten steel manufactured in the refining process 30 or the slab W manufactured in the casting process 31, and the component analysis unit 5 The actual value of the component of the molten steel or slab W analyzed in comparison with the upper limit value and the lower limit value of the component held by the component value holding unit 4, and as a result of the comparison, the component value of the molten steel or slab W The actual value falls between the upper limit value and lower limit value of the component held by the component value holding unit 4 If you were includes a continue decision section 6 to decide to send the molten steel or cast strip W to the lower, the.

Hereinafter, details of each step will be described with reference to FIG.
First, the steel type determination unit 2 (steel type determination step) determines the mechanical test characteristics of the target slab W from the product material specifications provided by the user (customer), that is, the mechanical test characteristics of the product material desired by the user. The steel type that satisfies the above conditions is determined, and the data of the determined steel type is transmitted to a refining process 30 that performs a refining process to generate molten steel.

Specifically, the steel type determination unit 2 determines a steel type that satisfies the user's required quality based on the specifications of the steel sheet that describes the required quality such as mechanical test characteristics (results of tensile test, bending test, impact test, etc.). .
For example, when it is assumed that a high-strength thin steel plate (high-tensile steel plate) is received from the user and the tensile strength is described as 800 MPa or more in the specifications of the high-strength steel plate, However, a steel type having a tensile strength of 800 MPa or more is selected and determined from the steel types manufactured so far.

In the first embodiment, it is assumed that the steel type that is the quality of the required tensile strength is determined based on the judgment of the steel type M. At this time, the upper limit value and the lower limit value of the components (Mn, C, Mo, Cr, P, etc.) of the slab W in the steel type M are associated with the data of the steel type M.
In the first embodiment, for example, the upper limit value and lower limit value of the component of the slab W in the steel type M are C = 0.14 to 0.16, Si = 0.20 to 0.28, Mn = 0.77. Suppose that it is set to -0.90, P = 0.020 or less. The upper limit value and the lower limit value of the component of the slab W in the steel type M are transmitted to the component value holding unit 4.

On the other hand, the component determination unit 3 (component determination step) determines the upper limit value and the lower limit value of the components of the molten steel or slab W from the specifications of the product material provided by the user (customer). The upper limit value and the lower limit value of the components of the molten steel or slab W are design values. Hereinafter, the upper limit value and the lower limit value of the components of the molten steel or slab W determined by the component determination unit 3 are simply referred to as “design values”.
Specifically, the component determination unit 3 is based on the value of the tensile test (the target mechanical test characteristic of the slab W, “specification value”) described in the steel sheet specification provided by the user (customer). In addition, the components of the molten steel or slab W satisfying this specification value are determined.

For example, from the mechanical test characteristics of the target slab W, the components of the slab W to be manufactured are: C = 0.12 to 0.18, Si = 0.15 to 0.35, Mn = 0.40 It is determined that 0.70 and P = 0.030 or less.
Thus, the upper limit value and lower limit value of the component of the slab W, that is, the design value of the component is determined. The determined design value of the component of the slab W is transmitted to the component value holding unit 4.

The component value holding unit 4 (component value holding step) is a storage device composed of a hard disk or the like, and the target product is the design value of the component of the molten steel or slab W determined by the component determining unit 3. Retained for each mechanical test property of the material. That is, the component value holding unit 4 holds the design values of the components of the slab W for each specification that has been ordered.
For example, the design values of the components of the slab Wa obtained from the specification A received (for example, C = 0.12 to 0.17, Si = 0.16 to 0.33, Mn = 0.7 to 0.99) , P = 0.029 or less) as a required component of the specification A (tensile strength of 800 MPa or more). In addition, the design values of the components of the slab Wa obtained from the ordered specification B (for example, C = 0.36 to 0.41, Si = 0.16 to 0.33, Mn = 0.6 to 0.89). , P = 0.029 or less) is held as a required component of the specification B (tensile strength is 900 MPa or more).

The component analysis part 5 (component analysis process) analyzes the actual value of the component of the molten steel manufactured by the refining process 30, or the slab W manufactured by the casting process 31, using an emission spectroscopic analyzer or the like. As a result of the analysis, it is assumed that the actual values of the components are detected as C = 0.13, Si = 0.16, Mn = 0.65, and P = 0.025.
The value of the component of the molten steel or slab W analyzed in this way is sent to the continuation determination unit 6 as the current actual value.

As shown in FIG. 1, the continuation determination unit 6 (continuation determination process) is held by the component value holding unit 4 and the actual value (analysis result) of the component of the molten steel or slab W analyzed by the component analysis unit 5. The component determination means for comparing the upper limit value and the lower limit value of the components in the steel type M, and the molten steel manufactured in the refining process 30 or the slab W manufactured in the casting process 31 are sent to the lower part to continue manufacturing. Continuation determining means for determining whether or not.

  The component determination means includes an upper limit value and a lower limit value of components in the steel type M from the component value holding unit 4 (for example, C = 0.14 to 0.16, Si = 0.20 to 0.28, Mn = 0.77 to 0.90, P = 0.020 or less). The value read from the component value holding unit 4 and the actual value of the molten steel analyzed by the component analysis unit 5 (for example, C = 0.13, Si = 0.16, Mn = 0.65, P = 0. 025).

  Comparing the values of these two components, it can be seen that the actual value of the molten steel includes values that deviate from the upper limit value and lower limit value of the component in the steel type M that has been read out, and becomes a retained material (component out-of-component product). As a result of the comparison, the manufactured molten steel is determined as a steel type M ′ different from the target steel type M. That is, it can be seen that the actual value of the component of the manufactured molten steel or slab W is the value of the component of the steel type M ′. Even when the actual value of the manufactured molten steel (slab W) is within the range of the read value, that is, the steel type M, the actual value is sent to the continuation determining means.

  The continuation determining means receives the component design values from the component value holding unit 4 (for example, C = 0.12 to 0.18, Si = 0.15 to 0.35, Mn = 0.40 to 0.70, P = 0.030 or less). The value read from the component value holding unit 4 and the actual value of the component of the molten steel or slab W determined as the steel type M ′ by the component determination means (for example, C = 0.13, Si = 0.16, Mn = 0.65, P = 0.025, etc.).

  Comparing the values of these two components, it can be seen that the actual values of the components of the molten steel are within the range of the design values of the components. That is, the molten steel of the steel type M ′ satisfies the quality required by the user. From this result, it is decided to continue the production of the slab W, and the molten steel is sent to the casting step 31. In the case of the slab W, it is determined that the production of the steel plate is continued in the same manner as described above.

  On the other hand, when the actual value of the component of the molten steel or slab W is out of the design value of the component of the molten steel or slab W, the sending of the molten steel or slab W to the lower part is canceled. In the case of molten steel, it returns to the secondary refining process 30 and the component adjustment is performed again. In the case of a slab W, the molten steel is remanufactured again by returning to the converter facility, or when the component of the slab W corresponds to the required quality of another customer, the slab W is converted to the customer. .

As described above, even if the retaining material for molten steel or slab W is produced in the steelworks by using the retaining material applicator 1 according to the present invention, in other words, the retaining material application method, the response Measures can be determined accurately and quickly, and it is possible to reduce inventory and time loss related to manufacturing.
[Second Embodiment]
Below, 2nd Embodiment of the reserve material allocation method and the reserve material allocation apparatus 1 concerning this invention is described based on figures.

The configuration of the reserve material applicator 1 according to the second embodiment is substantially the same as that of the first embodiment.
That is, the reserve material applicator 1 according to the second embodiment includes a steel type determination unit 2 that determines a steel type that satisfies a mechanical test characteristic (mechanical test characteristic of a product) of a target slab W, and a target slab W. A component determination unit 3 that determines design values (upper limit value and lower limit value) of components that satisfy the mechanical test characteristics , a component value holding unit 4 that stores design values of components determined by the component determination unit 3, and a refining process 30 The component analysis unit 5 that analyzes the actual value of the component of the molten steel manufactured in step 1 or the casting slab W manufactured in the casting step 31, and the actual value of the component of the molten steel or slab W analyzed by the component analysis unit 5 The design value of the component held in the component value holding unit 4 is compared, and as a result of the comparison, the actual value of the component of the molten steel or slab W is the design value of the component held in the component value holding unit 4 If it is in the range (between the upper limit and lower limit), send the molten steel or slab W to the lower part. And continue determination unit 6 for determining a point having the same.

However, the reserve material applicator 1 according to the second embodiment correlates the configuration of the component value holding unit 4, the design value of the component determined by the component determination unit 3, and the mechanical test characteristics of the target slab W. The estimated value of the mechanical test characteristic of the molten steel or slab W is estimated using the correlation between the component / characteristic analysis unit 7 for obtaining the relationship and the design value of the component and the mechanical test characteristic of the target slab W. The point which has the characteristic estimation part 8 to perform differs greatly from 1st Embodiment.

  As shown in FIG. 2, in the second embodiment, similarly to the first embodiment, the mechanical test characteristics of the slab W targeted by the steel type determining unit 2, that is, the specification value of the tensile test (tensile strength = 800 MPa The steel grade M satisfying the above is selected and determined, and the component determination unit 3 satisfies the design values of the tensile test and the design values of the components of the molten steel or slab W (C = 0.12 to 0.18, Si = 0.15-0.35, Mn = 0.40-0.70, P = 0.030 or less). Moreover, the upper limit value and lower limit value of the components in the steel type M are also extracted. On the other hand, the component analysis unit 5 analyzes the actual value of the component of the manufactured molten steel or slab W using an emission spectroscopic analysis device or the like, and sends the result to the continuation determination unit 6. It is assumed that the actual values of the components are detected as C = 0.12, Si = 0.16, Mn = 0.65, and P = 0.025.

The component value holding unit 4 of the second embodiment is designed for each steel type (for example, steel type M), the design value of the component determined by the component determining unit 3, and the specification value of the tensile test (the mechanical test characteristics of the target slab W). ) As a past actual value.
For example, component values of slab W manufactured in the past (C = 0.14 to 0.16, Si = 0.20 to 0.28, Mn = 0.77 to 0.90, P = 0.020 or less. When the steel grade M is satisfied , the steel grade M is held as a group.

  And in 2nd Embodiment, the correlation with the design value of a component and the mechanical test characteristic of the target slab W is calculated | required, From the actual value of the correlation and the component of the manufactured molten steel or slab W, Whether to estimate the mechanical test characteristics of the molten steel or slab W, compare the estimated value with the mechanical test characteristics of the target slab W, and continue production of the molten steel or slab W based on the result It is characterized by determining.

The component / characteristic analysis unit 7 (component / characteristic analysis step) is a component design value (upper limit value and value) determined by the component determination unit 3 for each steel type group (for example, a group of steel type M) from the component value holding unit 4. The lower limit value) and the mechanical test characteristic of the target slab W are read out, and the correlation between the design value of the component and the mechanical test characteristic of the target slab W is obtained based on the read value.
FIG. 3 is a diagram showing the design values of the components on the horizontal axis and the mechanical test characteristics (mechanical strength) of the target slab W on the vertical axis.

  As shown in FIG. 3, for example, the case 1 when the slab W of the steel type M is manufactured is extracted from the component value holding unit 4, and the actual value of the component in the case 1, for example, C = 0.13 is set on the horizontal axis. Plot, and the tensile strength (mechanical strength) at that time = 810 MPa is plotted on the vertical axis. In addition, Case 2 when steel slab W of steel type M was manufactured was extracted, the actual values of the components in Case 2 such as C = 0.12 were plotted on the horizontal axis, and the tensile strength at that time was 820 MPa on the vertical axis. Plot to. And such a procedure is repeated with respect to the data of all the steel types M in the component value holding | maintenance part 4. FIG.

  And when the slab W of the steel type M is manufactured, in the lower limit value A1 (C = 0.14) to the upper limit value A2 (C = 0.16) of the component, the tensile strength becomes S1 (for example, 800 MPa) or more, It can be determined from FIG. 3 that the quality requirement of the user is satisfied. In order to realize this determination, it is possible to determine whether or not a regression line is drawn from the points plotted in FIG. 3 and whether or not the regression line takes a value of S1 or more in the section [A1, A2]. .

As described above, the component / characteristic analysis unit 7 creates a graph indicating the correlation between the actual value of the component and the target mechanical test characteristic of the slab W.
The characteristic estimation unit 8 (characteristic estimation step) compares the actual value of the component analyzed by the component analysis unit 5 with the upper limit value and lower limit value of the component in the steel type M. And using the actual value of the compared molten steel or slab W and the correlation obtained by the component / characteristic analysis unit 7, the molten steel manufactured in the refining process 30 or the slab W manufactured in the casting process 31 Estimate mechanical test property estimates.

Specifically, from the group of steel types M held in the component value holding unit 4, the upper limit value and the lower limit value of the components in the steel type M (C = 0.14 to 0.16, Si = 0.20 to .0. 28, Mn = 0.77-0.90, P = 0.020 or less). The read value is compared with the actual values of the components of the molten steel or slab W (C = 0.12, Si = 0.16, Mn = 0.65, P = 0.025).

As a result, it can be seen that the actual value of the component includes a value that deviates from the upper limit value and the lower limit value of the component in steel type M. From this result, it is understood that the manufactured molten steel or slab W is a steel type M ′ different from the target steel type M.
And the graph which shows the correlation as shown in FIG. 3 using the actual value (C = 0.13, Si = 0.16, Mn = 0.65, P = 0.025 etc.) of the component in steel type M '. From the (regression line), the mechanical test characteristics of the manufactured molten steel or slab W are estimated. In the second embodiment, the estimated value of the mechanical test characteristic is set to tensile strength = 820 MPa.

  The continuation determination unit 6 deviates from the upper limit value and the lower limit value of the components in the steel type M determined by the steel type determination unit 2, that is, the component of the manufactured molten steel or slab W is the actual value of the component in the steel type M ′. Even if the estimated value of the mechanical test characteristic of the molten steel or slab W estimated by the characteristic estimation unit 8 falls within the target mechanical test characteristic range of the slab W, the molten steel or slab Decide to send W to the lower process.

Specifically, when a molten steel or a slab W of a different steel type (steel type M ′ different from the steel type M) is manufactured, an estimated value (tensile strength = 820 MPa) of mechanical test characteristics of the molten steel or slab W Then, the specification value of the mechanical test characteristics of the target slab W (tensile strength = 800 MPa or more) is compared.
As a result, it can be seen that the estimated value of the mechanical test characteristic is close to the target steel type M. Therefore, it can be seen that the manufactured molten steel or slab W satisfies the user's required specifications. From this result, it is determined to continue the production of the molten steel or slab W, and the molten steel or slab W is sent to the lower process (the casting process 31 or the rolling process 32).
[Third Embodiment]
Below, 3rd Embodiment of the reserve material allocation method and the reserve material allocation apparatus 1 concerning this invention is described based on figures. In addition, in 3rd Embodiment, the mechanical test characteristic (specification value) of the target slab W, the actual value of a component, the design value of a component, the upper limit value and the lower limit value in the steel grade M, etc. are the same as 1st Embodiment. Value.

The configuration of the reserve material applicator 1 according to the third embodiment is substantially the same as that of the first embodiment. That is, the reserve material applicator 1 of the third embodiment is the same in that it has a steel type determination unit 2, a component determination unit 3, a component value holding unit 4, a component analysis unit 5, and a continuation determination unit 6.
However, the reserve material applicator 1 according to the third embodiment uses a mechanical test characteristic held in the component value holding unit 4 to estimate an estimated value of the mechanical test characteristic of the molten steel or slab W. The point which has is greatly different from 1st Embodiment. The data held in the component value holding unit 4 is also significantly different from that in the first embodiment.

  As shown in FIG. 2, in the third embodiment, as in the first embodiment, a steel type M that satisfies the mechanical test characteristics (specification values of the tensile test) of the slab W targeted by the steel type determining unit 2. The component determining unit 3 determines the design value of the component of the molten steel or slab W that satisfies the specification value of the tensile test. On the other hand, the component analysis unit 5 analyzes the actual values of the components of the manufactured molten steel or slab W.

In addition, the design value of the component in 3rd Embodiment, the mechanical test characteristic of the target slab W, and the actual value of a component shall also be the same value as 1st Embodiment.
In the third embodiment, steel types having similar mechanical test characteristics are grouped, and based on the actual values of the components of the manufactured molten steel or slab W and the mechanical test characteristics of similar steel types read from the group, the molten steel or casting The mechanical test characteristic of the piece W is estimated, the estimated value is compared with the target mechanical test characteristic of the slab W, and it is determined whether or not to continue the production of the molten steel or the slab W based on the result. It is characterized by that.

The component value holding unit 4 of the third embodiment is a steel type having similar mechanical test characteristics (for example, steel type M, steel type M ′, steel type N, etc.) for each mechanical test item (tensile test, impact test, hardness test, etc.). Group and hold.
Specifically, the tensile test of the slab W is performed for each steel type, and when the same value or an approximate value is obtained as a result, the steel types are collectively held in one group. For example, steel grade M
As a result of a tensile test using the slab W, it is assumed that the tensile strength of the slab W is 800 MPa. Further, it is assumed that the tensile strength of the slab W is 820 MPa as a result of the tensile test using the slab W of the steel type M ′. In addition, as a result of a tensile test using a slab W of steel type N, it is assumed that the slab W has a tensile strength of 830 MPa. In this case, the steel type M, the steel type M ′, and the steel type N are held together in a group having a tensile strength of 800 MPa or more.

  In the grouping, other mechanical test characteristics, for example, the result of the hardness test may be used. That is, the hardness test of the slab W is performed for each steel type, and when the same value or an approximate value is obtained as a result, the steel types are held together in one group. For example, it is assumed that the hardness of the slab W is 300 HB as a result of the hardness test using the slab W of the steel type M. Further, it is assumed that the hardness of the slab W is 310 HB as a result of the hardness test using the slab W of the steel type M ′. Further, it is assumed that the hardness of the slab W is 320HB as a result of the hardness test using the slab W of the steel type N. In this case, the steel type M, the steel type M ′, and the steel type N are held together in a group of hardness = 300 HB or more.

  The characteristic estimation unit 8 compares the actual value of the component analyzed by the component analysis unit 5 with the upper limit value and lower limit value of the component in the steel type M. Then, referring to the actual values of the molten steel or slab W compared, the mechanical test characteristics of steel types M and N having similar mechanical test characteristics from the group of mechanical test characteristics held in the component value holding unit 4 Using the read values, the estimated values of the mechanical test characteristics of the molten steel manufactured in the refining process 30 or the slab W manufactured in the casting process 31 are estimated.

  Specifically, the upper limit value and the lower limit value of the components in steel type M (C = 0.14 to 0.16, Si = 0.20) from the group of tensile strength = 800 MPa or more held in the component value holding unit 4. -0.28, Mn = 0.77-0.90, P = 0.020 or less, etc.). The read value is compared with the actual values of the components of the molten steel or slab W (C = 0.12, Si = 0.16, Mn = 0.65, P = 0.025).

As a result, it can be seen that the actual value of the component includes a value that deviates from the upper limit value and the lower limit value of the component in steel type M. From this result, it is understood that the manufactured molten steel or slab W is a steel type M ′ different from the target steel type M.
And it is hold | maintained in the component value holding | maintenance part 4 with reference to the actual value (C = 0.13, Si = 0.16, Mn = 0.65, P = 0.025 etc.) of the component in steel type M '. From the group having a tensile strength of 800 MPa or more, the mechanical test characteristics of steel type M ′ having similar mechanical test characteristics are read, and using the read values, the molten steel manufactured in the refining process 30 or the casting manufactured in the casting process 31 is used. The estimated value of the mechanical test characteristic of the piece W is estimated. In the third embodiment, the estimated value of the mechanical test characteristic is set to tensile strength = 820 MPa.

  The continuation determination unit 6 deviates from the upper limit value and the lower limit value of the components in the steel type M determined by the steel type determination unit 2, that is, the component of the manufactured molten steel or slab W is the actual value of the component in the steel type M ′. Even if the estimated value of the mechanical test characteristic of the molten steel or slab W estimated by the characteristic estimation unit 8 falls within the target mechanical test characteristic range of the slab W, the molten steel or slab Decide to send W to the lower process.

Specifically, when the steel type of the produced molten steel or slab W is the steel type M ′, the estimated value of the mechanical test characteristics (tensile strength = 820 MPa) in the steel type M ′ and the target machine of the slab W The specification value of the test characteristics (tensile strength = 800 MPa or more) is compared.
As a result, it can be seen that the estimated value of the mechanical test characteristic is a value close to the target steel type M, and that the manufactured molten steel or slab W satisfies the user's required specifications. From this result, it is determined to continue the production of the molten steel or slab W, and the molten steel or slab W is sent to the lower process (the casting process 31 or the rolling process 32).
[Fourth Embodiment]
Below, 4th Embodiment of the reserve material allocation method and the reserve material allocation apparatus 1 concerning this invention is described based on figures. In addition, in 4th Embodiment, the mechanical test characteristic (specification value) of the target slab W, the actual value of a component, the design value of a component, the upper limit value and the lower limit value in the steel grade M, etc. are the same as 1st Embodiment. Value.

The configuration of the reserve material applicator 1 according to the fourth embodiment is substantially the same as that of the first embodiment. That is, the reserve material applicator 1 of the fourth embodiment is the same in that it has a steel type determination unit 2, a component determination unit 3, a component value holding unit 4, a component analysis unit 5, and a continuation determination unit 6.
However, the reserve material applicator 1 according to the fourth embodiment uses a mechanical test characteristic held in the component value holding part 4 to estimate an estimated value of the mechanical test characteristic of the molten steel or slab W. The point which has is greatly different from 1st Embodiment. The data held in the component value holding unit 4 is also significantly different from that in the first embodiment.

  As shown in FIG. 2, in the fourth embodiment, as in the first embodiment, the steel type M that satisfies the mechanical test characteristics (specification value of the tensile test) of the slab W targeted by the steel type determination unit 2. The component determining unit 3 determines the design value of the component of the molten steel or slab W that satisfies the specification value of the tensile test. On the other hand, the component analysis unit 5 analyzes the actual values of the components of the manufactured molten steel or slab W.

  In the fourth embodiment, steel types having similar mechanical test characteristics and steel types having mechanical test characteristics lower than those similar steel types are grouped, and the actual values of the components of the manufactured molten steel or slab W are read out from the group. The mechanical test characteristics of the molten steel or slab W are estimated from the mechanical test characteristics of similar steel types, the estimated value is compared with the mechanical test characteristics of the target slab W, and the molten steel or It is characterized by determining whether or not to continue the production of the slab W.

The component value holding unit 4 of the fourth embodiment has similar mechanical test characteristics (for example, steel type M, steel type M ′, steel type N, etc.) for each mechanical test characteristic (tensile strength: 800 MPa or more, 850 MPa or more, etc.) and Steel types (for example, steel type X, steel type Y, etc.) whose mechanical test properties are lower than those of similar steel types are grouped and held.
Specifically, a tensile test of the slab W is performed for each steel type, and as a result, a steel type when the same tensile strength or an approximate value is obtained and a tensile strength slightly lower than the target mechanical test characteristics are obtained. The steel grades in the case of being given are held together in one group. For example, it is assumed that the tensile strength of the slab W is 800 MPa as a result of the tensile test using the slab W of the steel type M. Further, it is assumed that the tensile strength of the slab W is 820 MPa as a result of the tensile test using the slab W of the steel type M ′. On the other hand, it is assumed that the tensile strength of the slab W of the steel type X is 795 MPa as a result of the tensile test. In addition, as a result of a tensile test using a slab W of steel type Y, it is assumed that the slab W has a tensile strength of 798 MPa. These steel types M, steel types M ′, steel types N, steel types X, and steel types Y are held together in a group of tensile strength = 800 MPa.

  The characteristic estimation unit 8 compares the actual value of the component analyzed by the component analysis unit 5 with the upper limit value and lower limit value of the component in the steel type M. Then, referring to the actual value of the molten steel or slab W compared, from the group of mechanical test characteristics held by the component value holding unit 4, from the steel type M, steel type N and similar steel types having similar mechanical test characteristics The mechanical test characteristics of steel type X and steel type Y whose mechanical characteristics deteriorate are read out, and the estimated value of the mechanical test characteristics of molten steel or slab W is estimated using the read values.

  Specifically, from the group of tensile strength = 800 MPa held in the component value holding unit 4, the upper limit value and lower limit value of the components in steel type M (C = 0.14 to 0.16, Si = 0.20). 0.28, Mn = 0.77-0.90, P = 0.020 or less). The read value is compared with the actual values of the components of the molten steel or slab W (C = 0.12, Si = 0.16, Mn = 0.65, P = 0.025).

As a result, it can be seen that the actual value of the component includes a value that deviates from the upper limit value and the lower limit value of the component in steel type M. From this result, it is understood that the manufactured molten steel or slab W is a steel type M ′ different from the target steel type M.
And it is hold | maintained in the component value holding | maintenance part 4 with reference to the actual value (C = 0.13, Si = 0.16, Mn = 0.65, P = 0.025 etc.) of the component in steel type M '. From the group having a tensile strength of 800 MPa or more, the mechanical test characteristics of steel type M ′ having similar mechanical test characteristics are read, and using the read values, the molten steel manufactured in the refining process 30 or the casting manufactured in the casting process 31 is used. The estimated value of the mechanical test characteristic of the piece W is estimated. In the fourth embodiment, the estimated value of the mechanical test characteristic is set to tensile strength = 820 MPa.

In the continuation determination unit 6, the upper limit value and the lower limit value of the components in the steel type M, the steel type N, the steel type X, and the steel type Y determined in the steel type determination unit 2 were deviated (out of components), that is, the manufactured molten steel or slab Even if the component of W becomes the actual value of the component in the steel type M ′, the estimated value of the mechanical test characteristic of the molten steel or slab W estimated by the characteristic estimation unit 8 is the mechanical test of the target slab W. In the case of entering the range of characteristics, it is decided to send the molten steel or slab W to the lower process.

Specifically, when the steel type of the produced molten steel or slab W is the steel type M ′, the estimated value of the mechanical test characteristics (tensile strength = 820 MPa) in the steel type M ′ and the target machine of the slab W The specification value of the test characteristics (tensile strength = 800 MPa or more) is compared.
As a result, it can be seen that the estimated value of the mechanical test characteristic is a value close to the target steel type M, and that the manufactured molten steel or slab W satisfies the user's required specifications. From this result, it is determined to continue the production of the molten steel or slab W, and the molten steel or slab W is sent to the lower process (the casting process 31 or the rolling process 32).

  According to the reserve material application method and reserve material applicator 1 described above, even if the molten steel or slab W becomes a reserve material in the steel mill, from the actual value of the manufactured molten steel or slab W, By estimating the mechanical test characteristics and comparing the estimated value with the specification value of the mechanical test characteristics of the target slab W, it is possible to accurately and quickly determine whether to continue manufacturing the molten steel or slab W. As a result, it is possible to reduce inventory and manufacturing time loss.

The embodiment disclosed this time should be considered as illustrative in all points and not restrictive.
In particular, in the embodiment disclosed this time, matters that are not explicitly disclosed, for example, operating conditions and operating conditions, various parameters, dimensions, weights, volumes, and the like of a component deviate from a range that a person skilled in the art normally performs. Instead, values that can be easily assumed by those skilled in the art are employed.

1 Reservation material appropriation device 2 Steel type determination part (steel type determination process)
3 component determination part (component determination process)
4 component value holding unit (component value holding step)
5 Component analysis section (component analysis process)
6 Continue decision part (continue decision process)
7 Component / Characteristic Analysis Department (Component / Characteristic Analysis Process)
8 Characteristic estimation unit (characteristic estimation process)
20 Steel Grade Determining Section 30 Refining Process 31 Casting Process 32 Rolling Process W Slab

Claims (8)

A refining process for refining hot metal to produce molten steel, a casting process for producing a slab from the molten steel produced in the refining process, and a rolling process for rolling a product material from the slab cast in the casting process. In the method of appropriating reserve materials to be carried out at steelworks that have
Based on the steel sheet specifications provided by the user, a steel type determination step for determining a steel type satisfying the mechanical test characteristics of the target slab from among steel types manufactured in the past ,
A component determination step for determining an upper limit value and a lower limit value of the components that satisfy the mechanical test characteristics of the target slab;
A component value holding step for holding the upper limit value and the lower limit value of the component determined in the component determination step for each mechanical test characteristic of the target slab;
A component analysis step of analyzing the actual values of the components of the molten steel manufactured in the refining step or the slab manufactured in the casting step;
The actual value of the component of the molten steel or slab analyzed in the component analysis step is compared with the upper limit value and the lower limit value of the component held in the component value holding step, and as a result of the comparison, the molten steel or Even if the actual value of the slab component deviates from the upper limit value and lower limit value of the component in the steel type determined in the steel type determination step, the actual value of the molten steel or slab component is the component value holding step. And a continuation determining step for determining that the molten steel or slab is to be sent to a lower step when it is between the upper limit value and the lower limit value of the component held in step (1). Appropriation method.   The component value holding step holds, for each steel type, the upper limit value and lower limit value of the component determined in the component determination step and the mechanical test characteristics of the target slab as past actual values. The method for applying a holding material according to claim 1. From the component value holding step, for each steel type, the upper limit value and lower limit value of the component determined in the component determination step and the mechanical test characteristics of the target slab are read, and the component determination is performed based on the read value. A component / characteristic analysis step for obtaining a correlation between the upper limit value and the lower limit value of the component determined in the process and the mechanical test characteristics of the target slab;
Using the correlation, and estimating the estimated value of the mechanical test characteristics of the molten steel or slab,
In the continuation determination step, the estimated value of the mechanical test property of the molten steel or slab estimated in the property estimation step even if it is outside the upper limit value and lower limit value of the component in the steel type determined in the steel type determination step However, when it falls within the range of the mechanical test characteristics of the target slab, it is determined to send the molten steel produced in the refining process or the slab produced in the casting process to the lower process. The method for applying a holding material according to claim 2 .   2. The method for applying a retaining material according to claim 1, wherein in the component value holding step, steel types having similar mechanical test characteristics are grouped and held for each item of the mechanical test. Characteristic estimation that reads out mechanical test characteristics of steel types having similar grouped mechanical test characteristics from the component value holding step, and calculates an estimated value of mechanical test characteristics of the molten steel or slab using the read values Having a process,
In the continuation determination step, the estimated value of the mechanical test property of the molten steel or slab estimated in the property estimation step even if it is outside the upper limit value and lower limit value of the component in the steel type determined in the steel type determination step However, when it falls within the range of the mechanical test characteristics of the target slab, it is determined to send the molten steel produced in the refining process or the slab produced in the casting process to the lower process. The method for applying a holding material according to claim 4 .   The component value holding step groups and holds steel types having similar mechanical test characteristics and steel types having lower mechanical test characteristics than the similar steel types for each mechanical test characteristic. How to apply the listed reserve From the component value holding step, read out the mechanical test characteristics of the steel types having similar mechanical test characteristics of the grouped group and the steel types whose mechanical test characteristics are lower than the similar steel types, and using the read values, the molten steel or A characteristic estimation step for estimating an estimated value of the mechanical test characteristic of the slab,
In the continuation determination step, the estimated value of the mechanical test property of the molten steel or slab estimated in the property estimation step even if it is outside the upper limit value and lower limit value of the component in the steel type determined in the steel type determination step However, when it falls within the range of the mechanical test characteristics of the target slab, it is determined to send the molten steel produced in the refining process or the slab produced in the casting process to the lower process. The method for applying the retaining material according to claim 6 . A refining process for refining hot metal to produce molten steel, a casting process for producing a slab from the molten steel produced in the refining process, and a rolling process for rolling a product material from the slab cast in the casting process. In the reserving material appropriation device implemented at the steelworks that have
Based on the steel sheet specifications provided by the user, a steel type determination unit that determines a steel type satisfying the mechanical test characteristics of the target slab from among steel types manufactured in the past ,
A component determining unit that determines an upper limit value and a lower limit value of a component that satisfies the mechanical test characteristics of the target slab;
A component value holding unit for holding the upper limit value and the lower limit value of the component determined by the component determining unit for each mechanical test characteristic of the target slab;
A component analysis unit for analyzing the actual value of the component of the molten steel produced in the refining process or the slab produced in the casting process;
The actual value of the component of the molten steel or slab analyzed by the component analysis unit is compared with the upper limit value and the lower limit value of the component held by the component value holding unit, and as a result of the comparison, the molten steel or Even if the actual value of the slab component deviates from the upper limit value and lower limit value of the component in the steel type determined by the steel type determining unit, the actual value of the molten steel or slab component is the component value holding unit. And a continuation deciding unit that decides to send the molten steel or slab to a lower process when it is between the upper limit value and the lower limit value of the components held in Appropriation device.

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