JP6028655B2 - Steel grade judgment method - Google Patents

Description

  The present invention relates to a steel type determination method for steel materials. In particular, the present invention relates to a method for accurately determining the steel type of a steel material in a steel material conveyance line.

Conventionally, a spark test or a fluorescent X-ray analysis has been performed mainly for the purpose of detecting contamination of a steel material of a steel type different from the steel type that is scheduled to be transported (hereinafter referred to as a different material) in a steel material transport line. It may be used to determine the steel type.
A steel type means the division divided by the composition of steel materials, and a composition range is defined for every steel type. Steel materials are classified into any steel type depending on their composition.
In addition, for the steel type determination of the steel material, the steel type of the steel material to be determined is scheduled to be transported at the time of determination (hereinafter referred to as the steel type scheduled to be transported at the time of this determination as appropriate). Determination of whether or not the steel type of the steel material to be determined is one of all the steel types that can be transported on the transport line.
The spark test is, for example, a method in which a grinder is pressed against a steel material and the steel type is determined based on the shape and color of the generated spark. The X-ray fluorescence analysis is a method for determining a steel type based on the wavelength and intensity of fluorescent X-rays generated from a steel material irradiated with X-rays.

Conventionally, when a steel type is determined in a transfer line, one of the steel type determination methods is applied to a steel material transferred on the same transfer line, among a spark test and a fluorescent X-ray analysis.
However, the range of steel types that can be determined by the spark test alone or the fluorescent X-ray analysis alone is narrow. For this reason, especially when multiple steel types of steel materials are conveyed on the same conveyance line, there are cases where sufficient accuracy of determination of the steel types cannot be obtained.

For the spark test, for example, the characteristics of the sparks for each steel type extracted from the captured image of the sparks of steel materials whose steel types are known are converted into data, and the characteristics of the sparks extracted from the captured image of the sparks of the steel materials for which the steel types are to be determined. A method has been proposed in which the steel type is automatically determined in comparison with the data of the spark characteristics (see Patent Document 1).
However, in the method described in Patent Document 1, although the steel type can be automatically determined, the range of the steel type that can be determined is equivalent to the conventional spark test, so it is difficult to increase the determination accuracy of the steel type. is there.

With respect to X-ray fluorescence analysis, a method has been proposed in which the analysis time is shortened and the correct answer rate of analysis is improved by specifying the element to be analyzed and setting the order of searching for the element to be analyzed (Patent Document 2). reference).
However, in the method described in Patent Document 2, although the accuracy of analysis of elements that can be analyzed conventionally increases, the range of steel types that can be determined is equivalent to that of conventional fluorescent X-ray analysis, so that the accuracy of determination of steel types can be increased. Have difficulty.

JP-A-9-145599 Japanese Patent Laid-Open No. 4-343052

  The present invention has been made to solve such problems of the prior art, and an object of the present invention is to provide a method for accurately determining the steel type of a steel material in a transport line.

  In the process of examining the solution to the above-mentioned problem, the present inventors have found that the spark test and the fluorescent X-ray analysis are in a relationship of complementing each other's drawbacks in determining the steel type. Specifically, the spark test is easy to determine the carbon content, but it is difficult to determine the type and amount of the alloy element, whereas the fluorescent X-ray analysis is an alloy that is difficult to determine the carbon content. It is a finding that the type and amount of elements are easy to determine. For this reason, the present inventors can expect to obtain sufficient judgment accuracy of the steel type by performing both the spark test and the fluorescent X-ray analysis on the steel material conveyed on the conveyance line and using both results. Thought.

For example, according to the spark test, when the planned steel type, which is the steel type scheduled to be conveyed at the time of determination, is a steel type of Cr-Mo steel having a carbon content of 0.20 mass% or less, the carbon content is If a Cr-Mo steel material exceeding 0.20% by mass is mixed, it can be determined that the steel type of the mixed steel material is not a planned steel type, but if a Mo steel steel material is mixed, the steel type of the mixed steel material is a planned steel type. It is determined that there is. On the other hand, when the steel type of Cr-Mo steel having a carbon content of 0.20 mass% or less is the planned steel type, according to the fluorescent X-ray analysis, when the steel material of Mo steel is mixed, the steel type of the mixed steel material is scheduled. Although it can be determined that it is not a steel type, if a steel material of Cr—Mo steel having a carbon content exceeding 0.20 mass% is mixed, it is determined that the steel type of the mixed steel material is a planned steel type.
However, if both the spark test and the fluorescent X-ray analysis are performed on the same steel material, the carbon amount can be determined by the spark test, and the Cr amount and the Mo amount can be determined by the fluorescent X-ray analysis. Therefore, when the steel type of Cr-Mo steel having a carbon content of 0.20% by mass or less is a planned steel type, even when the steel material of Cr-Mo steel having a carbon content exceeding 0.20% by mass is mixed, the Mo Even when steel materials are mixed, it can be determined that the steel type of the mixed steel material is not a planned steel type.

  On the other hand, in order to determine the steel type by both the spark test and the fluorescent X-ray analysis in the transport line, the result of the spark test for different steel materials and the result of the fluorescent X-ray analysis should not be linked as a result for the same steel material. There must be. For example, when a spark test is performed on the upstream side of the transport line in the transport direction and a fluorescent X-ray analysis is performed on the downstream side of the transport line in the transport direction, the transport is performed between the location where the spark test is performed and the location where the fluorescent X-ray analysis is performed. When a new steel material is carried in from the outside of the line, only the fluorescent X-ray analysis is performed on the steel material carried in, and no spark test is performed. At this time, when the steel test is performed by linking the result of the spark test and the result of the fluorescent X-ray analysis in the order in which they were applied (the result of the nth spark test and the nth The results of X-ray fluorescence analysis are linked, and the n-th steel material is judged based on both the linked results), and the spark test of the steel material closest to the upstream side of the transport line with respect to the steel material carried in Since the result is erroneously linked as a result of the spark test of the steel material that has been carried in, the steel type of the steel material that has been carried in cannot be determined using an appropriate result. Similarly, for all steel materials located upstream from the steel materials carried in, the result of the spark test and the result of the fluorescent X-ray analysis are mistakenly linked. It cannot be judged.

  In addition, when the steel material after the spark test is carried out of the conveyance line from between the place where the spark test is performed and the place where the fluorescent X-ray analysis is performed, the steel material taken out is fluorescent X-ray. No analysis is performed. For this reason, the result of the spark test of the steel that has been transported is treated as the result of the spark test of the steel that is closest to the transported upstream side of the transported steel (this steel shall not be transported outside the transport line). Is called. And since the result of the spark test for the steel material carried out and the result of the fluorescent X-ray analysis of the steel material closest to the upstream side in the conveyance direction with respect to the steel material carried out are mistakenly linked to the upstream side in the conveyance direction The steel type of the steel material to be used cannot be determined using appropriate results. The same applies to all the steel materials located on the upstream side of the steel materials carried out.

  As described above, it is possible to carry steel materials into or out of the conveyance line between the location where the spark test is performed in the steel conveyance line and the location where the fluorescent X-ray analysis is performed. For example, depending on the method of associating the result of the spark test with the result of the fluorescent X-ray analysis, the steel type of the steel material may not be determined using an appropriate result.

The present inventors have completed the present invention based on the above findings.
That is, in order to solve the above-mentioned problem, the present invention is a method for determining the steel type of a steel material conveyed on a conveyance line, in which a spark test and a fluorescent X-ray analysis are sequentially performed on the steel material conveyed on the conveyance line. A determination step of determining a steel type of the steel material based on a result of the spark test and the fluorescent X-ray analysis obtained by the analysis step, and a place where the spark test is performed on the transport line and the fluorescent X-ray The steel material for judging the steel type without carrying in the steel material to the conveying line and unloading the steel material from the conveying line between the places where the analysis is performed and the carbon content exceeds 0.10% by mass. 20 wt% or less is carbon steel, when any of a 1Cr steel and BBS steel, the determination step, to include the following first step and second step Providing steel type determination method of the steel according to symptoms.
(1) First step
Based on the result of the spark test on the steel material, the steel type of the steel material is a first steel type group including carbon steel and 1Cr steel having a carbon content of more than 0.10% by mass and 0.20% by mass or less, or BBS. While classifying into any one of steel, based on the result of the fluorescent X-ray analysis with respect to the said steel materials, the steel types of the said steel materials are set to either one of carbon steel or the 2nd steel type group containing 1Cr steel and BBS steel Classify.
(2) Second step
In the first step, when the steel type of the steel material is classified into the first steel type group based on the result of the spark test and further classified into carbon steel based on the result of the fluorescent X-ray analysis, the steel material This steel type is determined to be a carbon steel having a carbon content of more than 0.10% by mass and 0.20% by mass or less. In the first step, when the steel grade of the steel material is classified into the first steel grade group based on the result of the spark test, and further classified into the second steel grade group based on the result of the fluorescent X-ray analysis The steel type of the steel material is determined to be 1Cr steel. In the first step, when the steel type of the steel material is classified into BBS steel based on the result of the spark test and further classified into the second steel type group based on the result of the fluorescent X-ray analysis, the steel material Is determined to be BBS steel.

According to the present invention, both the spark test and the fluorescent X-ray analysis are performed on the same steel material, and the steel material is carried in between the location where the spark test is performed and the location where the fluorescent X-ray analysis is performed, The steel material is not carried out between the portion where the spark test is performed and the portion where the fluorescent X-ray analysis is performed. For this reason, the result of the spark test and the result of the fluorescent X-ray analysis are not erroneously associated with each other due to the carrying-in / out of the steel material, and the steel type can be determined using an appropriate result for the same steel material.
Further, as described above, according to the spark test, it is easy to determine the carbon amount, but it is difficult to determine the type and amount of the alloy element. On the other hand, according to the fluorescent X-ray analysis, the carbon amount is determined. However, it is easy to determine the type and amount of alloy elements. According to the present invention, since the steel type is determined using the results of both the spark test and the fluorescent X-ray analysis, the range of steel types that can be determined is widened, and the determination accuracy of the steel type is increased.
In the present invention, either the spark test or the fluorescent X-ray analysis may be performed first.

When the steel material for determining the steel type is one of carbon steel, 1Cr steel, and BBS steel having a carbon content of more than 0.10% by mass and not more than 0.20% by mass, the spark test alone, The steel type can only be classified into one of the first steel type group including carbon steel and 1Cr steel having a carbon content of more than 0.10% by mass and 0.20% by mass or less, or BBS steel. That is, carbon steel having a carbon content of more than 0.10% by mass and 0.20% by mass or less is classified into the same steel type (first steel type group) and the two cannot be distinguished. On the other hand, the fluorescent X-ray analysis alone can only classify the steel material of the steel into one of a carbon steel or a second steel type group including 1Cr steel and BBS steel. That is, 1Cr steel and BBS steel are classified into the same steel type (second steel type group) and cannot be distinguished from each other.
However, according to the present invention , by executing the second step based on the results of both the spark test and the fluorescent X-ray analysis, the steel material for determining the steel type is classified into three types of steel types (carbon content is 0.10% by mass). It is possible to discriminate into carbon steel, 1Cr steel, and BBS steel that exceed 0.20 mass%.

Further, the present invention is a method for determining a steel type of a steel material conveyed on a conveyance line, and includes an analysis step for sequentially performing a spark test and a fluorescent X-ray analysis on the steel material conveyed on the conveyance line, and the analysis step. A determination step of determining the steel type of the steel material based on the results of the obtained spark test and fluorescent X-ray analysis, and between the place where the spark test and the fluorescent X-ray analysis are performed on the transport line The steel material for determining the steel type is not Mo steel, Cu-Ni-Mn steel, Cu-Ni steel, and carbon content, without carrying in the steel material to the transport line and unloading the steel material from the transport line. When the Cr-Mo steel is less than 0.20 mass% and the Cr content is 0.20 mass% or more, the determination step includes the following third step and fourth step. It is provided as steels determination method of the steel which comprises a flop.
(1) 3rd step Based on the result of the spark test for the steel material, the steel type of the steel material is Mo steel, Cu—Ni—Mn steel, Cu—Ni steel, and Cr—Mo having a carbon content of 0.20 mass% or less. While classifying into any one of the 3rd steel type group containing steel, or Cr-Mo steel in which carbon amount exceeds 0.20 mass%, based on the result of the fluorescent X ray analysis with respect to the said steel materials, the steel types of the said steel materials Is classified into any one of Mo steel, Cu—Ni—Mn steel, Cu—Ni steel and Cr—Mo steel.
(2) Fourth step In the third step, the steel type of the steel material is classified into a third steel type group based on the result of the spark test, and further classified into Mo steel based on the result of the fluorescent X-ray analysis. When it is done, it determines with the steel grade of the said steel materials being Mo steel. In the third step, the steel type of the steel material was classified into a third steel type group based on the result of the spark test, and further classified into Cu-Ni-Mn steel based on the result of the fluorescent X-ray analysis. In this case, the steel type of the steel material is determined to be Cu-Ni-Mn steel. In the third step, when the steel type of the steel material is classified into a third steel type group based on the result of the spark test, and further classified into Cu-Ni steel based on the result of the fluorescent X-ray analysis, It is determined that the steel type of the steel is Cu-Ni steel. In the third step, when the steel type of the steel material is classified into a third steel type group based on the result of the spark test, and further classified into Cr-Mo steel based on the result of the fluorescent X-ray analysis, The steel type of the steel material is determined to be Cr-Mo steel having a carbon content of 0.20 mass% or less. In the third step, the steel type of the steel material is classified into Cr-Mo steel having a carbon content exceeding 0.20% by mass based on the result of the spark test, and Cr based on the result of the fluorescent X-ray analysis. When it is classified as -Mo steel, the steel type of the steel is determined to be Cr-Mo steel with a carbon content exceeding 0.20 mass%.

Steel materials for determining the steel type are Mo steel, Cu—Ni—Mn steel, Cu—Ni steel, Cr—Mo steel with a carbon content of 0.20 mass% or less, and Cr—Mo with a carbon content exceeding 0.20 mass%. In the case of any of the steels, in the spark test alone, the steel types of the steel materials are Mo steel, Cu—Ni—Mn steel, Cu—Ni steel, and Cr—Mo steel having a carbon content of 0.20 mass% or less. It can only be classified into one of the third steel type group including the Cr or the Mo—Cr—Mo steel whose carbon content exceeds 0.20 mass%. That is, although the Cr-Mo steel whose carbon content exceeds 0.20 mass% can be distinguished from the other four types of steel, the four types of steel are classified into the same steel type (third steel type group) and cannot be discriminated. . On the other hand, the fluorescent X-ray analysis alone can only classify the steel material into one of Mo steel, Cu—Ni—Mn steel, Cu—Ni steel, and Cr—Mo steel. That is, Cr-Mo steel having a carbon content of 0.20% by mass or less and Cr-Mo steel having a carbon content exceeding 0.20% by mass are classified into the same steel type (Cr-Mo steel). Can not.
However, according to the present invention , by performing the third step based on the results of both the spark test and the fluorescent X-ray analysis, the steel materials for determining the steel type are classified into five types of steel (Mo steel, Cu-Ni-Mn steel). , Cu—Ni steel, Cr—Mo steel having a carbon content of 0.20% by mass or less, and Cr—Mo steel having a carbon content exceeding 0.20% by mass).

Here, when the steel type of the steel material to be determined (determination target steel material) is the same as the steel type scheduled to be transported (scheduled steel type) by a spark test or fluorescent X-ray analysis It is determined whether or not the result of the spark test or the fluorescent X-ray analysis of the determination target steel material is within a predetermined determination criterion determined in advance according to the planned steel type. That is, if the result of the spark test or the fluorescent X-ray analysis is within a predetermined criterion, it is determined that the steel material is the same steel type as the planned steel type. Different material).
In consideration of the fact that the result of the spark test and the fluorescent X-ray analysis varies even if the predetermined judgment standard is the same steel type, regardless of whether the steel material is the same casting lot, for each steel type In many cases, it is determined based on variations in the results of spark tests and fluorescent X-ray analysis of a large number of steel materials.

On the other hand, in a steel material conveyance line, steel materials are often conveyed using a casting lot as a conveyance unit. That is, in many cases, a plurality of steel materials manufactured from slabs cast at the same timing are combined into one casting lot, and the steel materials are conveyed for each casting lot.
In the dissimilar material determination based on the predetermined determination criteria described above, as long as the steel type of the target steel material is the same as the planned steel type, even if the target steel material is a steel material mixed from a casting lot different from the planned casting lot, , It will not be determined as a different material.
However, in view of the recent situation in which demands for clarifying the manufacturing history for each steel material are increasing, even if the steel type of the steel material to be judged is the same as the planned steel type, the casting lot in which the steel material to be judged is scheduled It is desirable to determine whether or not the steel material is mixed from a different casting lot.

As a result of intensive studies on the above points, the present inventors have found that variations in the results of the spark test and fluorescent X-ray analysis in the same casting lot result in variations in the results of the spark test and fluorescent X-ray in different casting lots. Found it smaller. For this reason, as a criterion for determining whether or not the target steel material is a steel material of a scheduled casting lot, a criterion in a range smaller than the range of the predetermined criterion for determining the different material described above is used. I came up with a good idea.
That is, the present invention is a method for determining a steel type of a steel material conveyed on a conveyance line, and includes an analysis step for sequentially performing a spark test and a fluorescent X-ray analysis on the steel material conveyed on the conveyance line, and the analysis step. A determination step of determining the steel type of the steel material based on the results of the obtained spark test and fluorescent X-ray analysis, and between the place where the spark test and the fluorescent X-ray analysis are performed on the transport line In the determination step, when the steel material is scheduled to be transported with the casting lot as a transport unit in the transport line without carrying in the steel material into the transport line and unloading the steel material from the transport line. Is a result of a spark test of the steel material (hereinafter referred to as a determination target steel material) that is a determination target obtained in the analysis step, Whether or not it is within a first spark test criteria having a predetermined range length predetermined for a steel type of a casting lot scheduled to be (hereinafter referred to as a planned steel type), and the analysis step obtained above Based on whether or not the result of the fluorescent X-ray analysis of the determination target steel material is within the first fluorescent X-ray analysis determination standard having a predetermined range length predetermined for the planned steel type, the determination target steel material It is determined whether or not the steel type is the same as the planned steel type, and when it is determined in the determination step that the steel type of the determination target steel material is the same as the planned steel type, the same conveyance unit as the determination target steel material The second spark test plate having a predetermined range length based on the result of the spark test of the steel material first determined to be the same as the planned steel type (hereinafter referred to as a reference steel material) among Determining a standard, and if the result of the spark test of the determination target steel is outside the second spark test determination standard, the determination target steel is determined not to be a steel material of the scheduled casting lot, and A second fluorescent X-ray analysis standard having a predetermined range length is determined based on the result of the fluorescent X-ray analysis of a reference steel material, and the result of the fluorescent X-ray analysis of the determination target steel material is the second fluorescent X If it is outside the line analysis standard, the judgment target steel material further includes a casting lot judgment step for judging that the steel material of the scheduled casting lot is not a steel material of the scheduled casting lot, and the range length of the second spark test judgment standard is the planned steel type In consideration of only the variation in the result of the spark test in the same casting lot, the second fluorescent X-ray analysis determination criterion is determined in advance so as to be smaller than the range length of the first spark test determination criterion. The range length of In consideration of only the variation of the result of the fluorescent X-ray analysis within the same casting lot of the planned steel type, it is determined in advance so as to be smaller than the range length of the first fluorescent X-ray analysis determination criterion. It is also provided as a method for determining the steel type of a steel material .

According to the present invention , not only the determination as to whether or not the steel type of the target steel material is the same as the planned steel type, but also the determination as to whether or not the steel material is mixed from a casting lot different from the scheduled casting lot. Is also possible.

  According to the present invention, the steel type of the steel material can be accurately determined in the transport line.

FIG. 1 is a configuration diagram illustrating an example of a steel type determination system used in the steel type determination method for steel according to the first embodiment of the present invention. FIG. 2 is a diagram illustrating an example of a correspondence relationship between a list of steel types that are transported on a transport line, a first steel type list, and a second steel type list in the first embodiment of the present invention. FIG. 3 is a flowchart showing the steel type determination method in the first embodiment of the present invention. FIG. 4 is a diagram illustrating an example of a relationship between the first spark test determination criterion and the second spark test determination criterion. FIG. 5 is a diagram illustrating an example of a relationship between the first fluorescent X-ray analysis determination criterion and the second fluorescent X-ray analysis determination criterion.

<First Embodiment>
Hereinafter, the steel type determination method for steel according to the first embodiment of the present invention will be described taking the case where the steel is a steel pipe as an example, with reference to the attached drawings as appropriate. However, the steel material to which the present invention is applied is not limited to a steel pipe, and may be a steel bar or a steel plate.
In the steel type determination method according to the present embodiment, it is determined whether or not the steel type of the steel pipe to be determined is a planned steel type (a steel type that is scheduled to be conveyed).

FIG. 1 is a configuration diagram illustrating an example of a steel type determination system used in the steel type determination method according to the present embodiment.
As shown in FIG. 1, the steel type determination system 1 according to the present embodiment includes a transport line L that transports a steel pipe K, a spark test unit 2, a spark test calculation control unit 21, a fluorescent X-ray analysis unit 3, A fluorescent X-ray calculation control unit 31, a total calculation control unit 4, and a marking unit 5 are provided. In addition, the steel type determination system 1 includes a general PLC (Programmable Logic Controller) 6 that controls operations of the spark test unit 2 and the fluorescent X-ray analysis unit 3 based on an instruction from the general arithmetic control unit 4, and a general PLC 6. And a transport PLC 7 that controls the operation of the transport line L based on the instruction. In addition, in FIG. 1, the top steel pipe K1 is conveyed by the conveyance line L to the position of the spark test part 2, and after that, the 2nd steel pipe K2 and the 3rd steel pipe K3 are conveyed continuously. A plurality of steel pipes K (not shown) are continuously conveyed after the steel pipe K3. Moreover, in this embodiment, although the spark test part 2 is provided in the conveyance direction upstream of the conveyance line L rather than the fluorescent X-ray analysis part 3, any of the spark test part 2 and the fluorescent X-ray analysis part 3 is conveyed. It may be provided upstream in the direction.

  The spark test unit 2 images a spark generated by pressing a grinder against the steel pipe K, and transmits the captured image to the spark test calculation control unit 21. The spark test calculation control unit 21 collects spark data such as, for example, the total number of sparks, the burst spark rate, the blue rate, and the number of sparks from the captured image of the spark transmitted from the spark test unit 2. Here, the total number of sparks means the total number of streamline sparks whose shape is streamlined without sparks bursting and bursting sparks whose sparks burst. The bursting spark rate means the ratio of the number of bursting sparks to the total number of sparks. The blue rate means the degree of blue of the pixel area corresponding to the burst spark. The number of firewood sparks means the number of sparks in the shape of a firewood. The spark test calculation control unit 21 transmits the collected spark data to the general calculation control unit 4.

  The fluorescent X-ray analysis unit 3 irradiates the steel pipe K with X-rays, thereby detecting the fluorescent X-rays generated from the steel pipe K, and outputs an electric signal corresponding to the detected fluorescent X-rays to the fluorescent X-ray calculation control unit 31. Send to. The fluorescent X-ray calculation control unit 31 calculates the content of each alloy element based on the electrical signal transmitted from the fluorescent X-ray analysis unit 3. Then, the fluorescent X-ray calculation control unit 31 transmits the calculated content data of each alloy element to the general calculation control unit 4.

  The comprehensive calculation control unit 4 controls the operation of each part of the steel type determination system 1, and also includes spark data received from the spark test calculation control unit 21 and content data of each alloy element received from the fluorescent X-ray calculation control unit 31. Based on the above, the steel type is determined.

  The marking unit 5 performs marking indicating that the steel pipe K is made of a different material according to an instruction from the general arithmetic control unit 4. The marking is performed, for example, by applying oil-based paint to the steel pipe K or attaching a label.

  The general arithmetic control unit 4 is connected to a host computer 8 for managing the manufacturing information of the steel material, and receives the scheduled steel type of the steel pipe K transported by the transport line L from the host computer 8.

In the general arithmetic control unit 4, a list of steel types that can be classified from the spark data obtained by the spark test is determined corresponding to the spark data. For example, if spark data such as the total number of sparks for the steel pipe K1 is within a predetermined criterion according to the steel type A, the steel pipe K1 is classified as a steel type A, and the spark data for the steel pipe K2 corresponds to the steel type B. Therefore, the steel pipe K is classified into the steel type B if it is within the predetermined criterion. In this embodiment, the list of steel types that can be classified from the spark data is referred to as a first steel type list.
In the spark test, only the contents of carbon and some alloy elements can be detected, so the classification of the steel grade classification in the first steel grade list is not the same as the classification classification of all planned steel grades conveyed by the conveyance line L. Absent. In the first steel type list, some scheduled steel types are classified into a group (steel type group) including a plurality of scheduled steel types.

Further, in the general arithmetic control unit 4, a list of steel types that can be classified from the content data of each alloy element obtained by fluorescent X-ray analysis is determined corresponding to the content data. For example, if the content data of each alloy element for the steel pipe K1 is within the criteria determined in advance according to the steel type A, the steel pipe K1 is classified as the steel type A, and the content of each alloy element for the steel pipe K2 If the data is within the criterion determined in advance according to the steel type B, the steel pipe K is classified as the steel type B. In this embodiment, the list of steel types that can be classified from the content data is referred to as a second steel type list.
Since the amount of carbon cannot be determined in the fluorescent X-ray analysis, the classification of the steel types in the second steel type list is not the same as the classification of all scheduled steel types conveyed by the conveyance line L. In the second steel type list, some scheduled steel types are classified into a group (steel type group) including a plurality of scheduled steel types.

  FIG. 2 shows an example of a correspondence relationship between a list of all steel types conveyed in the conveyance line L, in other words, a list of all scheduled steel types, and a first steel type list and a second steel type list. The list of all the scheduled steel types, the first steel type list, and the second steel type list are stored in the general arithmetic control unit 4.

<Classification of planned steel types>
As shown in FIG. 2, the steel types (scheduled steel types) transported by the transport line L are roughly classified into carbon steel, BBS steel, low alloy steel, and medium / high alloy steel. Here, carbon steel, BBS steel, low alloy steel, and medium / high alloy steel are steel type names determined by the composition of each alloy, and BBS steel conforms to steel type SUJ2 defined in JIS G 4805. Steel grade.
Further, the carbon steel is not added with V, and the carbon content (mass%) (hereinafter, the carbon content (mass%) is represented by the bracketed symbol [C]), [C] ≦ 0.10, 0.10 <[C] ≦ 0.20, 0.20 <[C] ≦ 0.25, 0.25 <[C] ≦ 0.30, 0.30 <[C] ≦ 0.40, or 0 6 types of carbon steel with .40 <[C] ≦ 0.50, and 2 types of V with V added and carbon content of [C] ≦ 0.30 or 0.30 <[C] It is classified as added steel.
The low alloy steel is 1Cr steel, Mo steel, Cu—Ni—Mn steel, Cu—Ni steel, Cr—Mo steel with [C] ≦ 0.20, or Cr—Mo with [C]> 0.20. Classified as steel. 1Cr steel, Mo steel, Cu—Ni steel, Cu—Ni—Mn steel, and Cr—Mo steel are steel type names determined by the composition of the alloy, respectively.
Medium and high alloy steels are classified as Ni steel, 2Cr steel, 2Cr-W steel, 5Cr steel, 9Cr steel, or 9Cr-W steel. Ni steel, 2Cr steel, 2Cr-W steel, 5Cr steel, 9Cr steel, and 9Cr-W steel are steel type names determined by the alloy composition.

<Classification in the first steel type list>
On the other hand, as shown in FIG. 2, in the first steel type list, which is a list of steel types that can be classified from the results of the spark test, carbon steel (however, excluding carbon steel of 0.10 <[C] ≦ 0.20) and The classification of steel grades in BBS steel is the same as the classification of planned steel grades.
However, the classification of steel grades in carbon steel, low alloy steel, and medium / high alloy steels with 0.10 <[C] ≦ 0.20 is not the same as the classification of planned steel grades. In the first steel type list, carbon steels of 0.10 <[C] ≦ 0.20 cannot be distinguished from 1Cr steels and are classified into the same group (first steel type group). In the first steel type list, the low alloy steel includes a first steel type group including 1Cr steel and carbon steel of 0.10 <[C] ≦ 0.20, Mo steel, and Cu—Ni—Mn steel. , Cu—Ni steel and a group (third steel type group) including Cr—Mo steel with [C] ≦ 0.20, and Cr—Mo steel with [C]> 0.20. Furthermore, in the first steel type list, the medium / high alloy steel is not further classified as being a medium / high alloy steel.

<Classification in the second steel type list>
In the second steel type list, which is a list of steel types that can be classified from the results of the fluorescent X-ray analysis, the classification of the steel types in the medium and high alloy steels is the same as the classification of the planned steel types.
However, the classification of the steel types in the carbon steel, BBS steel and low alloy steel is not the same as the classification of the planned steel types. In the second steel type list, carbon steel is not further classified as being carbon steel. In the second steel type list, BBS steel cannot be distinguished from 1Cr steel and is classified into the same group (second steel type group). Further, in the second steel type list, the low alloy steel includes the second steel type group including 1Cr and BBS steel, Mo steel, Cu-Ni-Mn steel, Cu-Ni steel, and Cr-Mo steel. And classified.

<Steel grade determination method>
In the present embodiment, the steel type determination is performed as follows.
The transport PLC 7 shown in FIG. 1 drives the transport line L based on an instruction from the general arithmetic control unit 4 to transport the leading steel pipe K1 to the spark test unit 2.
The spark test unit 2 performs a spark test on the steel pipe K1, and transmits a captured image of the spark to the spark test calculation control unit 21. The spark test calculation control unit 21 collects spark data from the captured image of the spark transmitted from the spark test unit 2 and transmits the collected spark data to the general calculation control unit 4. When receiving the spark data, the general arithmetic control unit 4 transmits a spark test completion signal to the general PLC 6. The general PLC 6 that has received the signal of completion of the spark test causes the transport PLC 7 to drive the transport line L to transport the steel pipe K1 to the fluorescent X-ray analysis unit 3 and simultaneously transports the steel pipe K2 to the spark test unit 2. The fluorescent X-ray analysis unit 3 irradiates the steel pipe K1 with X-rays, thereby detecting the fluorescent X-rays generated from the steel pipe K1, and outputs an electrical signal corresponding to the detected fluorescent X-rays to the fluorescent X-ray calculation control unit 31. Send to. The fluorescent X-ray calculation control unit 31 calculates the content of each alloy element based on the electrical signal transmitted from the fluorescent X-ray analysis unit 3. Then, the fluorescent X-ray calculation control unit 31 transmits the calculated content data of each alloy element to the general calculation control unit 4. In this way, the spark test and the fluorescent X-ray analysis are performed on the steel material (analysis step).

  Next, the comprehensive calculation control unit 4 includes the spark data transmitted from the spark test calculation control unit 21 obtained in the above analysis step and the content data of each alloy element transmitted from the fluorescent X-ray calculation control unit 31. The steel type of the steel pipe K1 is determined based on the above (determination step). Hereinafter, a specific method of steel type determination in this determination step will be described with reference to the flowchart shown in FIG. 3 as appropriate.

First, the general arithmetic control unit 4 receives the planned steel type of the steel pipe K from the host computer 8 before the spark test and the fluorescent X-ray analysis are performed on the steel pipe K (step S0 in FIG. 3).
The general arithmetic control unit 4 determines whether or not the received scheduled steel type of the steel pipe K is included in the list of stored scheduled steel types (step S01 in FIG. 3).
If the received scheduled steel grade of the steel pipe K is not included in the list of stored scheduled steel grades, the general arithmetic control unit 4 warns that the received scheduled steel grade of the steel pipe K is a new scheduled steel grade. Is notified to the operator. The operator adds the new scheduled steel type to the list of scheduled steel types stored in the integrated calculation control unit 4, and changes the steel type determination logic described below so that the newly added steel type can also be determined. (Step S02 in FIG. 3). The steel type determination logic described below will be described by taking as an example a case where the received scheduled steel type of the steel pipe K is included in the list of scheduled steel types stored in the general arithmetic control unit 4.

  Next, based on the spark data received from the spark test calculation control unit 21, the general calculation control unit 4 selects the steel type of the steel pipe K that is the determination target by any steel type (or steel type group) included in the first steel type list. It is determined that there is (hereinafter, the determined steel type is referred to as a first determination steel type) (step S1 in FIG. 3). At this time, if any steel type included in the first steel type list cannot be determined, the general arithmetic control unit 4 marks the steel pipe K that is a determination target by the marking unit 5 to the effect that it cannot be determined, and to that effect Is transmitted to the host computer 8.

  Next, the comprehensive calculation control unit 4 determines the steel type of the steel pipe K that is the determination target based on the fluorescent X-ray analysis data (content data of each alloy element) received from the fluorescent X-ray calculation control unit 31 in the second steel type list. (Hereinafter, this determined steel type is referred to as a second determination steel type) (step S2 in FIG. 3). At this time, if any steel type included in the second steel type list cannot be determined, the general arithmetic control unit 4 marks the steel pipe K that is a determination target by the marking unit 5 to the effect that it cannot be determined, and to that effect Is transmitted to the host computer 8.

  Next, the comprehensive calculation control unit 4 includes the first determination steel type determined based on the spark data, the second determination steel type determined based on the fluorescent X-ray analysis data, and the scheduled steel type received from the host computer 8. The steel type is determined as follows.

First, the comprehensive calculation control unit 4 determines whether or not the first determination steel type and the second determination steel type are the corresponding steel types (step S3 in FIG. 3). Here, the steel grade corresponding to the first judgment steel type and the second judgment steel type specifically means a case corresponding to any of the following cases (a) to (e).
(A) The first judgment steel type is any one of carbon steels (for example, [C] ≦ 0.10), and the second judgment steel type is carbon steel.
(B) The first judgment steel type is BBS steel, and the second judgment steel type is the second steel type group (BBS steel or 1Cr steel).
(C) The first judgment steel type is the first steel type group (carbon steel of 0.10 <[C] ≦ 0.20 or 1Cr steel), and the second judgment steel type is the second steel type group (BBS steel, Or 1Cr steel).
(D) The first judgment steel type is a third steel type group (Mo steel, Cu—Ni—Mn steel, Cu—Ni, or [C] ≦ 0.20 Cr—Mo steel), and the second judgment steel type is It is either Mo steel, Cu-Ni-Mn steel, or Cr-Mo steel.
(E) The first judgment steel type is Cr—Mo steel with [C]> 0.20, and the second judgment steel type is Cr—Mo steel.
(E) The first judgment steel type is medium / high alloy steel, and the second judgment steel type is medium / high alloy steel (for example, Ni steel).

  When the first judgment steel type and the second judgment steel type are not corresponding steel types, for example, when the first judgment steel type is medium / high alloy steel and the second judgment steel type is carbon steel, a spark test and One of the fluorescent X-ray analysis may not be performed correctly. Therefore, the general arithmetic control unit 4 makes the determination impossible, marks the steel pipe K that is the determination target by the marking unit 5 to the effect that the determination is impossible, and transmits the fact to the host computer 8. As described above, since it is determined whether or not the first determination steel type and the second determination steel type are the corresponding steel types, the accuracy of the steel type determination is increased.

  When the first determination steel type and the second determination steel type are the corresponding steel types, the general arithmetic control unit 4 determines the steel type as follows.

<When the first judgment steel type is carbon steel or BBS steel>
The comprehensive calculation control unit 4 determines whether or not the first determination steel type is carbon steel or BBS steel (step S4 in FIG. 3). In addition, when the first determination steel type is the first steel type group (carbon steel of 0.10 <[C] ≦ 0.20 or 1Cr steel), the second determination steel type is carbon steel (described above). (Case (a)), this first determination steel type is determined to be any of carbon steel, and if the second determination steel type is the second steel type group (BBS steel or 1Cr steel) (described above (c) )), It is determined that the first determination steel type is not carbon steel (determined to be a low alloy steel).
When the first determination steel type is any one of carbon steel or BBS steel, the general arithmetic control unit 4 determines whether or not the first determination steel type is the same as the planned steel type (step S5 in FIG. 3). ). When the first judgment steel type is the first steel type group (carbon steel of 0.10 <[C] ≦ 0.20 or 1Cr steel), the expected steel type is 0.10 <[C] ≦ 0. .20 carbon steel, it is determined that the first judgment steel type is the same as the planned steel type.
When the first determination steel type is the same as the planned steel type, the integrated calculation control unit 4 determines that the steel type of the steel pipe K that is the determination target is the planned steel type, that is, is not a different material, and notifies the host computer 8 to that effect. Send to. On the other hand, if the first determination steel type is not the same as the planned steel type, the general arithmetic control unit 4 determines that the steel type of the steel pipe K that is the determination target is not the planned steel type, that is, is a different material, and that is the marking unit 5. To mark the steel pipe K and transmit the fact to the host computer 8.
When the planned steel grade is almost the same as the grade of the planned steel grade and the category of the first steel grade list, such as when the planned steel grade is carbon steel or BBS steel, the first judgment grade is the same as the planned steel grade. It is determined whether or not the steel type of the steel pipe K that is the determination target is a planned steel type depending on whether or not there is.

<When the first grade is medium / high alloy steel>
When the first determination steel type is not carbon steel or BBS steel, the general arithmetic control unit 4 determines whether or not the first determination steel type is medium / high alloy steel (step S6 in FIG. 3). When the first determination steel type is a medium / high alloy steel, the comprehensive calculation control unit 4 determines whether or not the second determination steel type is the same as the planned steel type (S7 in FIG. 3). When the second determination steel type is the same as the planned steel type, the comprehensive calculation control unit 4 determines that the steel type of the steel pipe K that is the determination target is the planned steel type, that is, is not a different material, and notifies the host computer 8 to that effect. Send to. On the other hand, if the second determination steel type is not the same as the planned steel type, the general arithmetic control unit 4 determines that the steel type of the steel pipe K that is the determination target is not the planned steel type, that is, is a different material, and the marking unit 5 To mark the steel pipe K and transmit the fact to the host computer 8.
When the planned steel grade is the same as that of the medium and high alloy steels, the second judgment grade is the same as the planned grade when the category of the planned grade is the same as that of the second grade list. It is determined whether or not the steel type of the steel pipe K that is the determination target is the planned steel type.

<When the first grade is either low alloy steel>
When the first judgment steel type is not any of carbon steel, BBS steel, and medium / high alloy steel, that is, when it is any of low alloy steel, the steel type is as follows (i) to (iii) Is determined (S8 in FIG. 3).

  (I) First, the comprehensive calculation control unit 4 determines whether or not the first determination steel type is the first steel type group (carbon steel of 0.10 <[C] ≦ 0.20 or 1Cr steel). . When the first judgment steel type is the first steel type group (since the first judgment steel type and the second judgment steel type correspond, in this case, the second judgment steel type is the second steel type group), the total calculation The control part 4 determines with the steel type of the steel pipe K which is a determination object being 1Cr steel, and determines whether a planned steel type is 1Cr steel. When the planned steel type is 1Cr steel, the general arithmetic control unit 4 determines that the steel type of the steel pipe K that is the determination target is the planned steel type, that is, is not a different material, and transmits that fact to the host computer 8. On the other hand, if the planned steel type is not 1Cr steel, the general arithmetic control unit 4 determines that the steel type of the steel pipe K that is the determination target is not the planned steel type, that is, is a different material, and the marking unit 5 notifies the steel pipe K to that effect. And sends a message to that effect to the host computer 8.

(Ii) When the first determination steel type is not the first steel type group (carbon steel of 0.10 <[C] ≦ 0.20 or 1Cr steel), the general arithmetic control unit 4 determines that the first determination steel type is third. It is determined whether it is a steel type group (Mo steel, Cu-Ni-Mn steel, Cu-Ni steel, or Cr-Mo steel of [C] ≤0.20). When the first determination steel type is the third steel type group, the comprehensive calculation control unit 4 determines whether the second determination steel type is any of Mo steel, Cu—Ni—Mn steel, and Cu—Ni steel. Determine. When the second judgment steel type is any one of Mo steel, Cu-Ni-Mn steel, and Cu-Ni steel, the general arithmetic control unit 4 determines whether or not the second judgment steel type is the same as the planned steel type. Determine. When the second determination steel type is the same as the planned steel type, the integrated calculation control unit 4 determines that the steel type of the steel pipe K that is the determination target is the planned steel type, that is, is not a different material, and notifies that to the upper computer. 8 to send. On the other hand, when the second judgment steel type is not the same as the planned steel type, the general arithmetic control unit 4 determines that the steel type of the steel pipe K that is the judgment target is not the planned steel type, that is, is a different material, and marks that fact. The steel pipe K is marked by the unit 5 and the fact is transmitted to the host computer 8.
On the other hand, when the first determination steel type is the third steel type group and the second determination steel type is not any of Mo steel, Cu—Ni—Mn steel, and Cu—Ni steel (that is, second determination). When the steel type is Cr-Mo steel), the general arithmetic control unit 4 determines that the steel type of the steel pipe K to be determined is Cr-Mo steel with [C] ≦ 0.20, and the planned steel type is [C ] It is judged whether it is Cr-Mo steel of ≦ 0.20. When the planned steel type is Cr—Mo steel with [C] ≦ 0.20, the comprehensive calculation control unit 4 determines that the steel type of the steel pipe K that is the determination target is the planned steel type, that is, is not a different material, A message to that effect is sent to the host computer 8. On the other hand, if the planned steel type is not a Cr—Mo steel with [C] ≦ 0.20, the comprehensive calculation control unit 4 determines that the steel type of the steel pipe K that is the determination target is not the planned steel type, that is, is a different material. The steel pipe K is marked by the marking unit 5 to that effect and transmitted to the host computer 8.

  (Iii) The first judgment steel type is the first steel type group (carbon steel of 0.10 <[C] ≦ 0.20 or 1Cr steel), and the third steel type group (Mo steel, Cu—Ni—Mn steel). , Cu—Ni steel, or [C] ≦ 0.20 Cr—Mo steel) (ie, when the first judgment steel type is [C]> 0.20 Cr—Mo steel), The general arithmetic control unit 4 determines that the steel type of the steel pipe K to be determined is Cr—Mo steel with [C]> 0.20, and the planned steel type is Cr—Mo steel with [C]> 0.20. It is determined whether or not there is. When the planned steel type is Cr—Mo steel with [C]> 0.20, the overall calculation control unit 4 determines that the steel type of the steel pipe K that is the determination target is the planned steel type, that is, is not a different material, A message to that effect is sent to the host computer 8. On the other hand, if the planned steel type is not a Cr—Mo steel with [C]> 0.20, the overall calculation control unit 4 determines that the steel type of the steel pipe K that is the determination target is not the planned steel type, that is, is a different material. The steel pipe K is marked by the marking unit 5 to that effect and transmitted to the host computer 8.

As described above, in the spark test alone, the carbon steel of 0.10 <[C] ≦ 0.20 and the 1Cr steel are classified into the same steel type (first steel type group), and cannot be distinguished from each other. On the other hand, with fluorescent X-ray analysis alone, 1Cr steel and BBS steel are classified into the same steel type (second steel type group) and cannot be distinguished from each other. However, by determining the steel type based on the results of both the spark test and the fluorescent X-ray analysis, the steel type of the steel pipe K that is the object of determination is changed to three types of steel (0.10 <[C] ≦ 0.20 carbon steel). 1Cr steel and BBS steel).
In the spark test alone, Cr—Mo steel with [C]> 0.20 is replaced with other four types of steel (Mo steel, Cu—Ni—Mn steel, Cu—Ni steel, [C] ≦ 0.20. Although it can be discriminated from (Cr-Mo steel), the four steel types are classified into the same steel type (third steel type group) and cannot be discriminated. On the other hand, with fluorescent X-ray analysis alone, Cr—Mo steel with [C] ≦ 0.20 and Cr—Mo steel with [C]> 0.20 are classified into the same steel type (Cr—Mo steel). Cannot be distinguished. However, by determining the steel type based on the results of both the spark test and the fluorescent X-ray analysis, the steel type of the steel pipe K that is the object of determination is classified into five types (Mo steel, Cu—Ni—Mn steel, Cu—Ni steel). , [C] ≦ 0.20 Cr—Mo steel, [C]> 0.20 Cr—Mo steel).

  Thus, if the steel type is determined using the results of both the spark test and the fluorescent X-ray analysis, the carbon amount and the type and amount of each alloy element can be known. The range of steel types that can determine the steel type is wider than when either one is applied. For this reason, the accuracy of the determination as to whether or not the steel type of the steel pipe K that is the determination target is the planned steel type is increased.

  In order to perform appropriate steel type determination in the transport line L, the first determination steel type determined by the spark test and the second determination steel type determined by the fluorescent X-ray analysis are not the determination results for the same steel pipe K. Don't be. When a new steel pipe K is introduced between the spark test section 2 and the fluorescent X-ray analysis section 3 from the outside of the transfer line, only the fluorescent X-ray analysis is performed on the introduced steel pipe K by the fluorescent X-ray analysis section 3. Therefore, the spark test by the spark test unit 2 is not performed. At this time, when the general arithmetic control unit 4 associates the first determination steel type determined by the spark test and the second determination steel type determined by the fluorescent X-ray analysis in the order in which each is determined ( The nth first judgment steel grade and the nth second judgment steel grade are linked to each other after starting the steel grade judgment, and the nth steel pipe K is graded based on the linked first judgment steel grade and second judgment steel grade. In the case of determination), the first determination steel type of the steel pipe K that is closest to the upstream side of the transport line with respect to the steel pipe K that has been carried in is erroneously associated as the first determination steel type of the steel pipe K that has been carried in. The steel type of the steel pipe K cannot be determined appropriately. Similarly, since the first determination steel type and the second determination steel type are erroneously associated with all the steel pipes K located upstream from the carried steel pipe K, the steel type of the steel pipe K cannot be properly determined. become.

  Further, when the steel pipe K after the spark test is carried out from between the spark test section 2 and the fluorescent X-ray analysis section 3 to the outside of the transport line, the steel pipe K carried out has fluorescent X-rays. The fluorescent X-ray analysis by the analysis unit 3 is not performed. For this reason, the 1st judgment steel type of the steel pipe K carried out is the 1st of the steel pipe K (this steel pipe K shall not be carried out of a conveyance line) nearest to the conveyance line upstream side with respect to the steel pipe K carried out. Treated as a grade. And since the 1st judgment steel type of the steel pipe K carried out and the 2nd judgment steel type of the steel pipe K nearest to the conveyance line upstream side with respect to the steel pipe K carried out are mistakenly linked, The steel type of the nearest steel pipe K cannot be determined appropriately. The same applies to all the steel pipes K located on the upstream side of the steel pipe K carried out.

Therefore, the steel type determination system 1 according to the present embodiment carries in the steel pipe K to the transport line L and unloads the steel pipe K from the transport line L between the spark test unit 2 and the fluorescent X-ray analysis unit 3. Is configured to not. Specifically, between the spark test unit 2 and the fluorescent X-ray analysis unit 3, the transport line L is not provided with a carry-in port or a carry-out port for the steel pipe K.
According to the steel type determination system 1 according to the present embodiment, both the spark test and the fluorescent X-ray analysis are performed on the same steel pipe K, and the steel pipe K is interposed between the spark test unit 2 and the fluorescent X-ray analysis unit 3. Is not carried in, and the steel pipe K is not carried out between the spark test unit 2 and the fluorescent X-ray analysis unit 3. For this reason, the first determination steel type determined by the spark test and the second determination steel type determined by the fluorescent X-ray analysis are not erroneously associated with each other due to the carry-in / out of the steel pipe K, and the same The steel type can be determined using the appropriate first determination steel type and second determination steel type for the steel pipe K.

In the first embodiment described above, a spark test or fluorescent X-ray analysis is performed to determine whether or not the steel type of the steel pipe K that is a determination target is the same as the steel type that is scheduled to be transported (scheduled steel type). Is determined based on whether or not the result of the spark test and the fluorescent X-ray analysis of the determination target steel pipe K is within a predetermined determination criterion determined in advance according to the planned steel type. That is, if the result of the spark test or the fluorescent X-ray analysis is within a predetermined criterion, it is determined that the steel pipe K is the same steel type as the planned steel type. (Different material) It is determined to be K. In consideration of the fact that the results of the spark test and the fluorescent X-ray analysis vary even if the predetermined judgment standard is the same steel type, regardless of whether or not the steel pipe K is the same casting lot, In many cases, it is determined from variations in the results of spark tests and fluorescent X-ray analysis of a large number of steel pipes P.
More specifically, the spark data obtained by performing a spark test on the determination target steel pipe K is compared with a predetermined determination criterion determined in advance for each steel type included in the first steel type list, and the spark data is obtained. Is within the predetermined criterion, it is determined that the steel type having the criterion is the first criterion steel type. Further, the fluorescent X-ray analysis data obtained by performing the fluorescent X-ray analysis on the determination target steel pipe K is compared with a predetermined determination criterion predetermined for each steel type included in the second steel type list, and the fluorescence If the X-ray analysis data is within a predetermined determination criterion, it is determined that the steel type having the determination criterion is the second determination steel type. And as mentioned above, based on the 1st judgment steel type and the 2nd judgment steel type, the steel type of judgment object steel pipe L is judged, and it is judged whether this is the same as a plan steel type. Note that the determination criteria for the first determination steel type and the second determination steel type are determined in advance according to the determination criteria for all the steel types conveyed by the conveyance line L including the planned steel type.

On the other hand, in the conveyance line L of the steel pipe K, the steel pipe K is often conveyed with a casting lot as a conveyance unit. That is, in many cases, a plurality of steel pipes K manufactured from slabs cast at the same timing are combined into one casting lot, and the steel pipe K is conveyed for each casting lot.
In the dissimilar material determination based on the predetermined determination criterion described above, as long as the steel type of the determination target steel pipe K is the same as the planned steel type, even if the determination target steel pipe K is a steel pipe K mixed from a casting lot different from the planned casting lot. Even if it is, it will not be determined as a different material.
However, in view of the recent situation in which demands for clarifying the manufacturing history of each steel pipe K are increasing, even if the steel type of the judgment target steel pipe K is the same as the planned steel type, the judgment target steel pipe K is scheduled. It is desirable to determine whether or not the steel pipe K is mixed from a casting lot different from the casting lot.

  As a result of intensive studies on the above points, the present inventors have found that variations in the results of the spark test and fluorescent X-ray analysis in the same casting lot result in variations in the results of the spark test and fluorescent X-ray in different casting lots. Found it smaller. For this reason, as a criterion for determining whether or not the determination target steel pipe K is a steel pipe K material of a scheduled casting lot, a range smaller than the predetermined criterion for determining the above-mentioned different material I came up with the idea of using criteria.

That is, when the steel pipe K is scheduled to be transported in the transport line L using the casting lot as a transport unit, as a preferable aspect, the general arithmetic control unit 4 transports the result of the spark test of the determination target steel pipe K. Whether or not the steel type (planned steel type) of the casting lot scheduled to be within the first spark test judgment standard having a predetermined range length determined in advance and the result of the fluorescent X-ray analysis of the judgment target steel pipe K Whether or not the steel type of the steel pipe K to be determined is the same as the planned steel type based on whether or not it is within the first fluorescent X-ray analysis determination standard having a predetermined range length predetermined for the planned steel type Determine.
And when it determines with the steel type of the determination target steel pipe K being the same as a schedule steel type, the comprehensive calculation control part 4 is initially planned among the steel pipes K conveyed by the same conveyance unit as the said determination target steel pipe K. A second spark test judgment standard having a predetermined range length is determined based on a result of a spark test of a steel pipe K determined to be the same as the steel type (hereinafter referred to as a reference steel pipe), and a spark test of the steel pipe K to be judged If the result is outside the second spark test criteria, it is judged that the judgment target steel pipe K is not a steel material of a scheduled casting lot. In addition, the comprehensive calculation control unit 4 determines a second fluorescent X-ray analysis standard having a predetermined range length based on the result of the fluorescent X-ray analysis of the reference steel pipe K, and performs the fluorescent X-ray analysis of the determination target steel pipe K. If the result is out of the second fluorescent X-ray analysis standard, it is determined that the determination target steel pipe K is not a steel material of a scheduled casting lot.

  Specifically, the total calculation control unit 4 has a casting lot No. of the steel pipe K that is scheduled to be conveyed. Is transmitted from the host computer 8. The total calculation control unit 4 is the same casting lot number. Among the steel pipes K having the first steel pipe K, the steel type K (different material judgment) is determined according to the first spark test judgment standard and the first fluorescent X-ray analysis judgment standard. When it is determined that the first steel pipe K is not a different material (the steel type of the first steel pipe K is the same as the planned steel type), the general arithmetic control unit 4 determines the same casting lot No. In addition to performing the steel type determination (dissimilar material determination) according to the first spark test determination standard and the first fluorescent X-ray analysis determination standard for the second and subsequent steel pipes K having the second, the second spark test determination standard and It is also determined whether or not the steel pipe K is a scheduled casting lot based on the second fluorescent X-ray analysis determination criterion.

The second spark test determination criterion is a predetermined range length (based on the result of the spark test of a steel pipe K (hereinafter referred to as a reference steel pipe, which is the first steel pipe K in the above example) first determined not to be a different material. 2α). The range length (2α) of the second spark test criteria is smaller than the range length of the first spark test criteria, considering only the variation in the results of the spark test in the same casting lot of the planned steel type. Is determined in advance. If the result of the spark test of the second and subsequent determination target steel pipes K is outside the second spark test determination standard, the general arithmetic control unit 4 determines that the determination target steel pipe K is not a steel pipe of the scheduled casting lot. To do.
For example, when the measured value of the total number of sparks for the reference steel pipe K is Y, the second spark test determination standard for the total number of sparks is determined as (Y−α) to (Y + α). . If the measured value of the total number of sparks for the second and subsequent judgment target steel pipes K is outside this second spark test judgment standard, the judgment target steel pipe K is not a steel pipe of the scheduled casting lot, that is, the standard steel pipe K. It is determined that it is not a steel pipe of the same casting lot. The range length (2α) of the second spark test determination criterion is, for example, 6 times the variation (standard deviation) of the total number of sparks of the steel pipe K in the same casting lot. The range length (2α) of the second spark test determination criterion is determined for each spark data.

The second fluorescent X-ray analysis determination criterion is a predetermined range length based on the result of the fluorescent X-ray analysis of the reference steel pipe K (first steel pipe K in the above example) that was initially determined not to be a different material. Determined to have (2β). The range length (2β) of the second fluorescent X-ray analysis determination criterion is determined based on the first fluorescent X-ray analysis determination criterion in consideration of only the variation in the result of the fluorescent X-ray analysis within the same casting lot of the planned steel type. It is determined in advance so as to be smaller than the range length. If the result of the fluorescent X-ray analysis of the second and subsequent determination target steel pipes K is out of the second fluorescent X-ray analysis determination standard, the comprehensive calculation control unit 4 determines that the determination target steel pipe K is a steel pipe of the scheduled casting lot. It is determined that it is not.
For example, when the analytical value of a certain alloy element Y for the reference steel pipe K is Z mass%, the second fluorescent X-ray analysis determination criterion for the alloy element Y is (Z−β) mass% to (Z + β). ) Determined by mass%. If the analysis value of the alloy element Y for the second and subsequent determination target steel pipes K is outside this second spark test determination standard, the determination target steel pipe K is not a steel pipe of a scheduled casting lot, that is, a reference steel pipe It is determined that the steel pipe is not in the same casting lot as K. The range length (2β) of the second spark test criterion is, for example, 6 times the variation (standard deviation) in the composition of the steel pipe K in the same casting lot. The range length (2β) of the second spark test determination criterion is determined for each alloy element.

FIG. 4 is a diagram illustrating an example of a relationship between the first spark test determination criterion and the second spark test determination criterion. FIG. 4 (a) shows the relationship between the two standards for the total number of sparks, and FIG. 4 (b) shows the relationship between the two standards for the bursting spark rate. The horizontal axis in FIG. 4 means the number of steel pipes K that have been conveyed, and the vertical axis in FIG. 4 shows the value of each spark data.
As shown in FIG. 4, the first spark test determination criterion is set to a constant value regardless of the difference in the scheduled casting lot. In the example shown in FIG. 4A, the first spark test determination standard for the total number of sparks is set to 50 to 3500 pieces (range length: 3450 pieces), and in the example shown in FIG. The first spark test criterion for is set to 10 to 32% (range length: 22%).

As shown in FIG. 4, the total number of sparks and the burst spark rate of the first steel pipe K (data points filled in black in FIG. 4) of each of the scheduled casting lots A, B, and C are all first. It is assumed that it is determined to be the same as the planned steel type (not a different material) because it falls within the spark test criteria. In this case, a predetermined range length (2α) that is smaller than the range length of the first spark test determination standard, with the total number of sparks and the burst spark rate of the first steel pipe K of each casting lot A, B, and C as references. ) Is determined. For example, when the total number of sparks of the first steel pipe K of the casting lot A is Y1, the second spark test determination criterion for the second and subsequent steel pipes K of the casting lot A is (Y1-α)- (Y1 + α) is determined. When the total number of sparks of the first steel pipe K of the casting lot B is Y2, the second spark test determination criterion for the total number of sparks for the second and subsequent steel pipes K of the casting lot B is (Y2-α) To (Y2 + α). The same applies to the casting lot C. The same applies to the bursting spark rate.
In the example shown in FIG. 4, the range length (2α) of the second spark test criterion for the total number of sparks is 420, and the range length (2α) of the second spark test criterion for the burst spark rate is 10.8. %, Each of which is smaller than the range length of the first spark test criterion.

In the example shown in FIG. 4, since the total number of sparks and the bursting spark rate of the second and subsequent steel pipes K of the respective casting lots A, B and C are all within the second spark test criteria, both It is determined that the pipe is a scheduled casting lot.
The above determination is preferably performed for all spark data, but can be performed for any spark data. Further, when it is determined that the first steel pipe K of each casting lot is a different material, the second spark test determination is made based on the spark data of the steel pipe K that is first determined not to be a different material after the second one. What is necessary is just to determine a standard.

FIG. 5 is a diagram illustrating an example of a relationship between the first fluorescent X-ray analysis determination criterion and the second fluorescent X-ray analysis determination criterion. 5 (a) shows the relationship between the two criteria for Mn, FIG. 4 (b) shows the relationship between the two criteria for Mo, FIG. 5 (c) shows the relationship between the two criteria for Ni, and FIG. 5 (d). Indicates the relationship between the two criteria for Cr. The horizontal axis in FIG. 4 means the number of steel pipes K that have been transported, and the vertical axis in FIG. 4 shows the analysis value of each alloy element.
As shown in FIG. 5, the first fluorescent X-ray analysis determination criterion is set to a constant value regardless of the planned casting lot difference. In the example shown in FIG. 5A, the first fluorescent X-ray analysis determination criterion for Mn is set to 0.45 to 1.15 mass% (range length: 0.70 mass%), and FIG. In the example shown in FIG. 5 (c), the first fluorescent X-ray analysis determination criterion for Mo is set to 0.06 to 1.10% by mass (range length: 1.04% by mass). Then, the first fluorescent X-ray analysis determination criterion for Ni is set to 0.21 to 3.00 mass% (range length: 2.79 mass%), and in the example shown in FIG. The first fluorescent X-ray analysis determination criterion is set to 0.00 to 1.65% by mass (range length: 1.65% by mass).

As shown in FIG. 5, the analysis values of the respective alloy elements of the first steel pipe K (data points filled in black in FIG. 5) of each of the planned casting lots D, E, and F are all first. It is assumed that it is determined to be the same as the planned steel type (not a different material) because it is within the fluorescent X-ray analysis determination criteria. In this case, a predetermined range length that is smaller than the range length of the first fluorescent X-ray analysis determination criterion, using the analysis values of the respective alloy elements of the first steel pipe K of each casting lot D, E, and F as references. A second fluorescent X-ray analysis criterion having (2β) is determined. For example, when the analysis value of Mn of the first steel pipe K of the casting lot D is Y1% by mass, the second fluorescent X-ray analysis determination criterion for the second and subsequent steel pipes K of the casting lot D is (Y1 -Β) mass% to (Y1 + β) mass%. When the analysis value of Mn of the first steel pipe K of the casting lot E is Y2% by mass, the second fluorescent X-ray analysis determination criterion for Mn for the second and subsequent steel pipes K of the casting lot E is ( Y2-β) mass% to (Y2 + β) mass%. The same applies to the casting lot F. The same applies to other alloy elements.
In the example shown in FIG. 5, the range length (2β) of the second fluorescent X-ray analysis criterion for Mn is 0.18% by mass, and the range length (2β) of the second fluorescent X-ray analysis criterion for Mo. Is 0.24 mass%, the range length (2β) of the second fluorescent X-ray analysis criterion for Ni is 0.86 mass%, the range length of the second fluorescent X-ray analysis criterion for Cr (2β) Are determined to be 0.24% by mass, and are values smaller than the range length of the first fluorescent X-ray analysis criterion.

In the example shown in FIG. 5, the Mn analysis value of the second steel pipe K of the casting lot F (FIG. 5A) and the Ni analysis value of the sixth steel pipe K of the casting lot F (FIG. 5C). ) Is outside the second spark test criteria, it is judged that none of them is a steel pipe of the scheduled casting lot F.
In addition, although it is preferable to implement | achieve said determination about the analytical value of all the alloy elements, it can also be performed with respect to the analytical value of arbitrary alloy elements. In addition, when it is determined that the first steel pipe K of each casting lot is a different material, the second is determined based on the analysis value of the alloy element of the steel pipe K that is first determined not to be a different material after the second one. What is necessary is just to determine a spark test criteria.

<Second Embodiment>
Next, a steel type determination method for steel according to the second embodiment of the present invention will be described.
The steel type determination method of the steel material according to the present embodiment is a method of determining which steel type of all the steel types that can be transported by the transport line L is the steel type of the steel pipe K to be determined.
That is, in the steel type determination method according to the present embodiment, the steel type of the steel pipe K to be determined is transported based on the first determination steel type and the second determination steel type without determining whether or not the steel type is the same as the planned steel type. It is determined which of the steel types included in the list (FIG. 2) of all the steel types conveyed by the line L corresponds.
Therefore, except for not determining whether or not the steel type is the same as the planned steel type, the determination logic is the same as that of the first embodiment, and thus detailed description thereof is omitted here.

In addition, the steel types determined in the first and second embodiments are not limited to the steel types illustrated in FIG. 2, and are based on the result of either one of the spark test and the fluorescent X-ray analysis, or both results. Any steel grade can be used as long as it can be judged. Further, the carbon content category in carbon steel or the like is not limited to the exemplified category, and any category may be used.
Alternatively, the fluorescent X-ray analysis unit 3 may perform fluorescent X-ray analysis on the portion of the steel pipe K shaved with a grinder or the like in order to perform a spark test in the spark test unit 2. In this way, since the oxidized scale and the like on the surface of the steel pipe K are removed, the analysis accuracy of the fluorescent X-ray analysis is increased.
Furthermore, the total arithmetic control unit 4 may be provided with notification means such as a display and a speaker, and the notification result may be notified by this notification means.

DESCRIPTION OF SYMBOLS 1 ... Steel type determination system 2 ... Spark test part 21 ... Spark test calculation control part 3 ... X-ray fluorescence analysis part 31 ... X-ray fluorescence calculation control part 4 ... Total calculation control part 5 ... Marking part L ... Conveying line

Claims (3)

A method for determining the steel type of a steel material conveyed through a conveyance line,
An analysis step of sequentially performing a spark test and a fluorescent X-ray analysis on the steel material conveyed in the conveyance line;
A determination step of determining a steel type of the steel material based on a result of the spark test and fluorescent X-ray analysis obtained by the analysis step,
Between the place where the spark test is performed in the transport line and the place where the fluorescent X-ray analysis is performed, the steel material is not carried into the transport line and the steel material is not transported out of the transport line ,
When the steel material for determining the steel type is any one of carbon steel, 1Cr steel and BBS steel having a carbon content of more than 0.10% by mass and 0.20% by mass or less,
The determination step includes
Based on the result of the spark test on the steel material, the steel type of the steel material is a first steel type group including carbon steel and 1Cr steel having a carbon content of more than 0.10% by mass and 0.20% by mass or less, or BBS. While classifying into any one of steel, based on the result of the fluorescent X-ray analysis with respect to the said steel materials, the steel types of the said steel materials are set to either one of carbon steel or the 2nd steel type group containing 1Cr steel and BBS steel A first step of classification;
In the first step, when the steel type of the steel material is classified into the first steel type group based on the result of the spark test and further classified into carbon steel based on the result of the fluorescent X-ray analysis, the steel material The steel type is determined to be a carbon steel having a carbon content of more than 0.10% by mass and 0.20% by mass or less,
In the first step, when the steel grade of the steel material is classified into the first steel grade group based on the result of the spark test, and further classified into the second steel grade group based on the result of the fluorescent X-ray analysis The steel material type is determined to be 1Cr steel,
In the first step, when the steel type of the steel material is classified into BBS steel based on the result of the spark test and further classified into the second steel type group based on the result of the fluorescent X-ray analysis, the steel material A second step of determining that the steel type is BBS steel;
A method for determining the type of steel material. A method for determining the steel type of a steel material conveyed through a conveyance line,
An analysis step of sequentially performing a spark test and a fluorescent X-ray analysis on the steel material conveyed in the conveyance line;
A determination step of determining a steel type of the steel material based on a result of the spark test and fluorescent X-ray analysis obtained by the analysis step,
Between the place where the spark test is performed in the transport line and the place where the fluorescent X-ray analysis is performed, the steel material is not carried into the transport line and the steel material is not transported out of the transport line,
The steel materials for determining the steel type are Mo steel, Cu-Ni-Mn steel, Cu-Ni steel, Cr-Mo steel having a carbon content of 0.20 mass% or less, and Cr- with a carbon content exceeding 0.20 mass%. If it is any of Mo steel,
The determination step includes
Based on the result of the spark test on the steel material, the steel type of the steel material includes Mo steel, Cu-Ni-Mn steel, Cu-Ni steel, and Cr-Mo steel having a carbon content of 0.20 mass% or less. While classifying into either one of steel grade group or Cr-Mo steel with carbon content exceeding 0.20 mass%, based on the result of fluorescent X-ray analysis for the steel material, the steel grade of the steel material is Mo steel, Cu -A third step of classifying any one of Ni-Mn steel, Cu-Ni steel and Cr-Mo steel;
In the third step, when the steel type of the steel material is classified into a third steel type group based on the result of the spark test and further classified into Mo steel based on the result of the fluorescent X-ray analysis, the steel material The steel grade is determined to be Mo steel,
In the third step, the steel type of the steel material was classified into a third steel type group based on the result of the spark test, and further classified into Cu-Ni-Mn steel based on the result of the fluorescent X-ray analysis. In this case, it is determined that the steel type of the steel is Cu-Ni-Mn steel,
In the third step, when the steel type of the steel material is classified into a third steel type group based on the result of the spark test, and further classified into Cu-Ni steel based on the result of the fluorescent X-ray analysis, It is determined that the steel type of the steel is Cu-Ni steel,
In the third step, when the steel type of the steel material is classified into a third steel type group based on the result of the spark test, and further classified into Cr-Mo steel based on the result of the fluorescent X-ray analysis, The steel type of the steel material is determined to be Cr-Mo steel having a carbon content of 0.20 mass% or less,
In the third step, the steel type of the steel material is classified into Cr-Mo steel having a carbon content exceeding 0.20% by mass based on the result of the spark test, and Cr based on the result of the fluorescent X-ray analysis. -When classified as Mo steel, the steel type of the steel material is a fourth step for determining that the carbon content is Cr-Mo steel with a carbon content exceeding 0.20 mass%;
Steels determination method of the steel material you comprising a. A method for determining the steel type of a steel material conveyed through a conveyance line,
An analysis step of sequentially performing a spark test and a fluorescent X-ray analysis on the steel material conveyed in the conveyance line;
A determination step of determining a steel type of the steel material based on a result of the spark test and fluorescent X-ray analysis obtained by the analysis step,
Between the place where the spark test is performed in the transport line and the place where the fluorescent X-ray analysis is performed, the steel material is not carried into the transport line and the steel material is not transported out of the transport line,
In the transport line, it is planned to transport steel materials using a casting lot as a transport unit,
In the determination step, the result of a spark test of the steel material (hereinafter referred to as a determination target steel material) that is the determination target obtained in the analysis step is a steel type (hereinafter referred to as the steel lot) of the casting lot that is scheduled to be transported. Whether or not it is within a first spark test determination standard having a predetermined range length determined in advance for a predetermined steel type), and the result of the fluorescent X-ray analysis of the determination target steel material obtained by the analysis step, Whether or not the steel type of the steel material to be judged is the same as the planned steel type based on whether or not the steel type is within a first fluorescent X-ray analysis judgment standard having a predetermined range length predetermined for the planned steel type. Judgment,
When it is determined in the determination step that the steel type of the determination target steel material is the same as the planned steel type, among the steel materials conveyed in the same conveyance unit as the determination target steel material, first, the same as the planned steel type A second spark test determination standard having a predetermined range length is determined based on the result of the spark test of steel material determined to be (hereinafter referred to as reference steel material), and the result of the spark test of the determination target steel material is If it is outside the second spark test judgment standard, the judgment target steel material is judged not to be a steel material of the scheduled casting lot, and a predetermined range based on the result of the fluorescent X-ray analysis of the standard steel material A second fluorescent X-ray analysis standard having a length is determined, and if the result of the fluorescent X-ray analysis of the determination target steel material is outside the second fluorescent X-ray analysis standard, the determination target steel material is scheduled. Casting cast Further comprising a casting lot determining step is not the very steel,
The range length of the second spark test criterion is smaller than the range length of the first spark test criterion in consideration of only the variation in the result of the spark test in the same casting lot of the planned steel type. As determined in advance,
The range length of the second fluorescent X-ray analysis criterion is determined based on the first fluorescent X-ray analysis criterion in consideration of only the variation in the result of the fluorescent X-ray analysis within the same casting lot of the planned steel type. steels determination method of the steel material you characterized in that it is predetermined to be smaller than the range length.

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