EP0159386A1 - Method of controlling mill pacing - Google Patents
Method of controlling mill pacing Download PDFInfo
- Publication number
- EP0159386A1 EP0159386A1 EP84104769A EP84104769A EP0159386A1 EP 0159386 A1 EP0159386 A1 EP 0159386A1 EP 84104769 A EP84104769 A EP 84104769A EP 84104769 A EP84104769 A EP 84104769A EP 0159386 A1 EP0159386 A1 EP 0159386A1
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- EP
- European Patent Office
- Prior art keywords
- rolling
- time
- extracted
- materials
- heating furnace
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
- B21B37/78—Control of tube rolling
Definitions
- This invention relates to a method of controlling mill pacing wherein an extraction pitch of a heating furnace is determined while the progress of rolling is controlled in a rolling equipment wherein a plurality of serial rolling mills are provided downstream of the heating furnace in which a plurality of materials are rested on a furnace hearth integrally moving the materials and can be successively extracted.
- a multiplicity of materials to be rolled are present in a rolling line consisting of a heating furnace and a plurality of rolling mills.
- the number of rolling mills under the control is numerous and the number of pipes under the control is numerous, whereby it has been very difficult to shorten a cycle time.
- the techniques of controlling the respective rolling mills and the heating furnace in each of the cases of the techniques the operations have relied on the experiences and the skill of the operations, whereby it has been impossible to improve the productivity to an ideal extremity.
- the present invention has as its object the provision of a method of controlling a mill pacing in a rolling equipment wherein the operating conditions of a rolling line as a whole is optimized to improve the productivity.
- the present invention contemplates that, in a method of controlling a mill pacing in a rolling equipment wherein a plurality of serial rolling mills are provided downstream of a heating furnace in which a plurality of materials are rested on a furnace hearth integrally moving with the materials and can be successively extracted, respective rolling cycle times are sought from periods of time between the starts of rolling in respective rolling mills of a subsequent material to be extracted from the heating furnace and the readiness for rolling of the following material in the respective rolling mills, the maximum value of the above-described respective rolling cycle times is assumed as an extraction cycle time of the subsequent material to be extracted to thereby presuppose an extraction time of the subsequent material to be extracted from the heating furnace, allowable retard periods of time of the materials immediately before the respective rolling sills are predetermined, it is confirmed that the presupposed retard periods of time of the subsequent materials to be extracted immediately before the respective rolling mills are within the aforesaid allowable retard periods of time, and further, it is confirmed that a heating cycle time of the subsequent material to be
- Fig. 1 is a diagram of control system, showing an embodiment, in which the present invention is applied to a rolling equipment for seamless steel pipes. More specifically, this rolling equipment is a rolling line for seamless steel pipes according to the Mannessmann-plug mill system, wherein the material, which has been heated in a heating furnace 11, is pierced and rolled in a piercer 12, rolled for pipe-expanding and elongating the material in an elongater 13, rolled to a length of a pipe having a wall thickness substantially equivalent to the product wall thickness in a plug mill 14, the inner and outer surfaces of the pipe-shaped material are polished by two reelers 15 and the wall thickness reduction and pipe-expanding to a certain extent are effected, and the material is finished to be a pipe having an outer diameter of a predetermined value in a sizer 16, thus enabling to provide a final product.
- the heating furnace 11 is of a rotary furnace hearth type, in which a plurality of materials are rested on furnace hearth integrally moving the
- the heating furnace 11 is controlled by a heating furnace control device 21 and the mills 12 through 16 are controlled respective rolling mill control devices 22 through 26.
- An actual result of extraction of the material obtained in the heating furnace control device 21 and actual results of rolling of the materials obtained in the respective rolling mill control devices 22 through 26 are transmitted to a calculating means 27.
- the calculating means 27 determines the optimal extraction time in the heating furnace 11 and makes it possible to transmit the extraction time to the heating furnace control device 21.
- the calculating means 27 calculates and pressupposes respective rolling cycle times MCT between the starts of rolling in the respective rolling mills 12 through 16 of a subsequent material to be extracted from the heating furnace 11 and the completion of the preparation for rolling of the following material on the basis of a rolling schedule.
- the rolling cycle time MCT is defined as a period of time between the time of starting the rolling and time of completing the preparation for the rolling as indicated by a rolling starting signal P 1 and a following material rolling readiness signal P 2 in Fig. 3.
- respective presuppoosed cycle times MCT are calculated on the basis of actual result cycle times MCT collected in the respective rolling mill control devices 22 through 26.
- the respective presupposed rolling cycle times MCT are calculated on the basis of rolling speeds, rolling lengths, required idle times and the like in the respective mills 12 through 16. More specifically, the aforesaid rolling cycle time MCT is the truly required rolling cycle time in the rolling mill under the control.
- the period of time between the completion of preparation for the following material and the start of rolling is a loss time lying idle for the rolling mill under the control. Therefore, it is desirable that the loss times be eliminated in all of the rolling mills, however, the loss times in all of the rolling mills cannot be eliminated because the rolling cycle times MCT are different from one rolling mill to another. Then, if the loss time is eliminated in the rolling mill (equipment under critical condition) having the largest rolling cycle time MCT, then it becomes possible to improve the productivity to the utmost under given conditions. In other words, this means that the subsequent material should be extracted from the heating furnace 11 by the rolling cycle time of one of the mills 12 through 16, which has the largest rolling cycle time MCT.
- the calculating means 27 adds the largest value of the rolling cycle times MCT relating to the aforesaid subsequent material to be extracted, i.e. an assumed extraction cycle time to the latest actual result extraction time of the heating furnace 11 transimitted from the heating furnace control device 21, to thereby assume an extraction time of the subsequent material to be extracted.
- the calculating means 27 previously determines allowable retard periods of time for the materials immediately before the mills 12 through 16, confirms that the presupposed retard periods of time of the subsequent materials to be extracted immediately before the mills 12 through 16 are within the range of the aforesaid allowable retard periods of time, and when the presupposed retard periods of time are beyond the range of the allowable retard periods of time, the calculating means 27 performs again the calculation and presupposition of respective rolling cycle times MCT and the provisional calculation of extraction time.
- the aforesaid allowable retard periods of time will be determined in the following manner.
- a theoretical radiation calculation formula (the relationship of the lowered value of the temperature of a pipe material with the elapsed time) on the dimensions (outer diameter and wall thickness) of the pipe materials in the respective mills 12 through 16 is sought, while, the relationships between the temperature of the pipe material and defects on the inner surface of the pipe material and between the temperature of the pipe material and wear of the rolling tools, etc. are sought on the basis of the actual results, and it is determined within what retard period of time at the largest the rolling can be started in order to roll the pipe material within the range of suitable temperature.
- the calculation of the presupposed retard periods of time immediately before the mills 12 through 16 and the confirmation of that the presupposed retard periods of time are within the range of the allowable retard period of time are carried out in the following manner. Namely, if a presupposed rolling cycle time MCT of a material No. i counted from the latest material (1) to be started for rolling in a rolling mill No. x is made to be MCTx(i), a target extraction time of the subsequent material (n) to be extracted from the heating furnace 11 is made to be Tn and an actual result time when the latest material to be started for rolling in the rolling mill No. x is extracted from the heating furnace 11 is made to be T 1 , then a presupposed retard period of time h x of the subsequent material to be extracted immediately before the rolling mill No. x is sought through the following equation.
- an allowable retard period of time in the rolling mill No. x is made to be r x and a difference f x between r x and the presupposed retard period of time h x is sought through the following equation.
- the calculating means 27 calculates and presupposes the periods of time for awaiting the rolling immediately before the mills 12 through 16, i.e. retard periods of time.
- the retard periods of time are within the range of allowable values for all of the rolling sills, it is judged that extraction can be made, and when the retard period of time exceeds the allowable retard period of time in any one of the rolling mills, it is judged that extraction cannot be made.
- the calculating means 27 calculates a heating critical cycle time HCT sufficient for applying heat of a predetermined value to the respective materials including the subsequent material to be extracted and the latest material to be extracted, which are present in the heating furnace 11, on the basis of the rolling schedule. More specifically, the calculating means 27 calculates the heating critical cycle time sufficient for applying heat of the predetermined value to the respective materials being present in the heating furnace 11 through the following equation.
- CTm is a furnace neck extraction cycle time to a material of lot No. m in looking from the side of extraction
- Dm a diameter of the material of lot No. m
- L m a length of the material of lot No. m.
- the calculating means 27 judges whether or not the aforesaid heating critical cycle time HCT is secured between the subsequent material to be extracted and its preceding material to be extracted. When it is judged that the heating critical cycle time HCT can be secured, the calculating means 27 transmits the aforesaid assumed extraction time to the heating furnace control device 21 as the optimal extraction time for the subsequent material to be extracted.
- the calculating means 27 repeats the calculation and presupposition of the respective rolling cycle times MCT, assumption of the extraction time, confirmation of that the presupposed retard period of time is within the allowable retard period of time and confirmation of that the heating critical cycle time can be secured.
- the rolling start signal necessary for determining the rolling cycle times MCT in the mills 12 through 16 and the subsequent material rolling readiness signal are determined as shown in Table 1.
- Figs. 4A and 4B are histograms showing the relationship between the loss time and the number of materials N in the equipment under critical condition in the operating system according to the prior art and in the operating system according to the present invention, respectively, when the materials each having a diameter of 230 mm and a length of 1,535 mm are loaded into the heating furnace in two rows and rolled into steel pipes each having an outer diameter of 273.6 mm, a wall thickness of 6.35 mm and a length of 11,705 mm.
- an average loss tine in the operating system according to the prior art is 1.08 sec.
- an average loss time in the operating system accordingto the present invention is 0.33 sec., thus remarkably improving the productivity according to the present invention.
- the present invention is applicable not only to the production line for seamless steel pipes in accordance with the Mannessmann-plug mill system but also to the rolling equipment for seamless steel pipes according to the Mandrel mill system, Assel mill system and the like. Further, the present invention is applicable to the rolling equipment for rolling bar steel, wire steel and the like. Furthermore, the present invention is applicable irrespective of the number of rolling mills, and on the contrary, the larger the number of rolling mills is, the greater the effects can be attained.
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Control Of Metal Rolling (AREA)
- Metal Rolling (AREA)
Abstract
Description
- This invention relates to a method of controlling mill pacing wherein an extraction pitch of a heating furnace is determined while the progress of rolling is controlled in a rolling equipment wherein a plurality of serial rolling mills are provided downstream of the heating furnace in which a plurality of materials are rested on a furnace hearth integrally moving the materials and can be successively extracted.
- In a rolling equipment for seamless steel pipes, shapes and the like, a multiplicity of materials to be rolled are present in a rolling line consisting of a heating furnace and a plurality of rolling mills. Particularly, as compared with the plate rolling, in the seamless steel pipe rolling, the number of rolling mills under the control is numerous and the number of pipes under the control is numerous, whereby it has been very difficult to shorten a cycle time. In the aforesaid rolling equipment of the prior art, there have been observed the techniques of controlling the respective rolling mills and the heating furnace, in each of the cases of the techniques the operations have relied on the experiences and the skill of the operations, whereby it has been impossible to improve the productivity to an ideal extremity.
- In addition, as a technique for reference, there is a method of controlling a heating furnace described in Patent Kokai (Laid-Open) No. 127812/79 issued by the Patent Office of Japan. However, this method of controlling contemplates that the relations between the elapsed time and the temperature of piercing are sought for the heating furnace and a piecer to thereby control the furnace temperature of the heating furnace, and hence, such a disadvantage has been presented that the conditions of the group of sills in a posterior process following that in the piercer cannot be grasped.
- The present invention has as its object the provision of a method of controlling a mill pacing in a rolling equipment wherein the operating conditions of a rolling line as a whole is optimized to improve the productivity.
- To achieve the above-described object, the present invention contemplates that, in a method of controlling a mill pacing in a rolling equipment wherein a plurality of serial rolling mills are provided downstream of a heating furnace in which a plurality of materials are rested on a furnace hearth integrally moving with the materials and can be successively extracted, respective rolling cycle times are sought from periods of time between the starts of rolling in respective rolling mills of a subsequent material to be extracted from the heating furnace and the readiness for rolling of the following material in the respective rolling mills, the maximum value of the above-described respective rolling cycle times is assumed as an extraction cycle time of the subsequent material to be extracted to thereby presuppose an extraction time of the subsequent material to be extracted from the heating furnace, allowable retard periods of time of the materials immediately before the respective rolling sills are predetermined, it is confirmed that the presupposed retard periods of time of the subsequent materials to be extracted immediately before the respective rolling mills are within the aforesaid allowable retard periods of time, and further, it is confirmed that a heating critical cycle time is secured which is sufficient for applying heat of a predetermined value to the subsequent material to be extracted through the latest material to be loaded, whereby the subsequent material is extracted at the aforesaid presupposed extraction time.
-
- Fig. 1 is a diagram of control system showing an embodiment, in which the present invention is applied to a rolling equipment for seamless steel pipes;
- Fig. 2 is a flow chart showing control steps of a calculating means in the above embodiment;
- Fig. 3 is an explanatory view showing the definition of a rolling cycle time in the above embodiment;
- Fig. 4A is a histogram showing the relationship between the loss time and the number of materials in the equipment under critical condition of the conventional system; and
- Fig. 4B is a histogram showing the relationship between the loss time and the number of materials in the equipment under critical according to the present invention.
- Description will hereunder be given of an embodiment of the present invention with reference to the drawings.
- Fig. 1 is a diagram of control system, showing an embodiment, in which the present invention is applied to a rolling equipment for seamless steel pipes. More specifically, this rolling equipment is a rolling line for seamless steel pipes according to the Mannessmann-plug mill system, wherein the material, which has been heated in a heating furnace 11, is pierced and rolled in a
piercer 12, rolled for pipe-expanding and elongating the material in anelongater 13, rolled to a length of a pipe having a wall thickness substantially equivalent to the product wall thickness in aplug mill 14, the inner and outer surfaces of the pipe-shaped material are polished by tworeelers 15 and the wall thickness reduction and pipe-expanding to a certain extent are effected, and the material is finished to be a pipe having an outer diameter of a predetermined value in asizer 16, thus enabling to provide a final product. In addition, the heating furnace 11 is of a rotary furnace hearth type, in which a plurality of materials are rested on furnace hearth integrally moving the materials, and can be successively extracted. - In the above rolling equipment, the heating furnace 11 is controlled by a heating
furnace control device 21 and themills 12 through 16 are controlled respective rollingmill control devices 22 through 26. An actual result of extraction of the material obtained in the heatingfurnace control device 21 and actual results of rolling of the materials obtained in the respective rollingmill control devices 22 through 26 are transmitted to a calculatingmeans 27. As will be described below, the calculatingmeans 27 determines the optimal extraction time in the heating furnace 11 and makes it possible to transmit the extraction time to the heatingfurnace control device 21. - The operation of the calculating
means 27 is shown in Fig. 2. More specifically, the calculating means 27 calculates and pressupposes respective rolling cycle times MCT between the starts of rolling in therespective rolling mills 12 through 16 of a subsequent material to be extracted from the heating furnace 11 and the completion of the preparation for rolling of the following material on the basis of a rolling schedule. Here, the rolling cycle time MCT is defined as a period of time between the time of starting the rolling and time of completing the preparation for the rolling as indicated by a rolling starting signal P1 and a following material rolling readiness signal P 2 in Fig. 3. Then, after pierced materials of the same lot in material quality, dimensions and the like as the subsequent material to be extracted have been passed through themills 12 through 16, respective presuppoosed cycle times MCT are calculated on the basis of actual result cycle times MCT collected in the respective rollingmill control devices 22 through 26. Whereas, before pierced materials of the same lot as the subsequent materials have not yet been passed through themills 12 through 16, the respective presupposed rolling cycle times MCT are calculated on the basis of rolling speeds, rolling lengths, required idle times and the like in therespective mills 12 through 16. More specifically, the aforesaid rolling cycle time MCT is the truly required rolling cycle time in the rolling mill under the control. The period of time between the completion of preparation for the following material and the start of rolling is a loss time lying idle for the rolling mill under the control. Therefore, it is desirable that the loss times be eliminated in all of the rolling mills, however, the loss times in all of the rolling mills cannot be eliminated because the rolling cycle times MCT are different from one rolling mill to another. Then, if the loss time is eliminated in the rolling mill (equipment under critical condition) having the largest rolling cycle time MCT, then it becomes possible to improve the productivity to the utmost under given conditions. In other words, this means that the subsequent material should be extracted from the heating furnace 11 by the rolling cycle time of one of themills 12 through 16, which has the largest rolling cycle time MCT. In consequence, the calculatingmeans 27 adds the largest value of the rolling cycle times MCT relating to the aforesaid subsequent material to be extracted, i.e. an assumed extraction cycle time to the latest actual result extraction time of the heating furnace 11 transimitted from the heatingfurnace control device 21, to thereby assume an extraction time of the subsequent material to be extracted. - Here, if the assumed extraction cycle time determined from the respective rolling cycle times MCT as described above is too short, then the loss times in the
respective mills 12 through 16 are decreased, however, there occur some cases where materials are retarded immediately before themills 12 through 16, thus leading to deteriorated product quality and considerably worn rolling tools such as reduction rolls due to lowered temperature of the material. Therefore, thecalculating means 27 previously determines allowable retard periods of time for the materials immediately before themills 12 through 16, confirms that the presupposed retard periods of time of the subsequent materials to be extracted immediately before themills 12 through 16 are within the range of the aforesaid allowable retard periods of time, and when the presupposed retard periods of time are beyond the range of the allowable retard periods of time, the calculatingmeans 27 performs again the calculation and presupposition of respective rolling cycle times MCT and the provisional calculation of extraction time. - More specifically, the aforesaid allowable retard periods of time will be determined in the following manner. To cite a seamless steel pipe for example, a theoretical radiation calculation formula (the relationship of the lowered value of the temperature of a pipe material with the elapsed time) on the dimensions (outer diameter and wall thickness) of the pipe materials in the
respective mills 12 through 16 is sought, while, the relationships between the temperature of the pipe material and defects on the inner surface of the pipe material and between the temperature of the pipe material and wear of the rolling tools, etc. are sought on the basis of the actual results, and it is determined within what retard period of time at the largest the rolling can be started in order to roll the pipe material within the range of suitable temperature. - Furthermore, the calculation of the presupposed retard periods of time immediately before the
mills 12 through 16 and the confirmation of that the presupposed retard periods of time are within the range of the allowable retard period of time are carried out in the following manner. Namely, if a presupposed rolling cycle time MCT of a material No. i counted from the latest material (1) to be started for rolling in a rolling mill No. x is made to be MCTx(i), a target extraction time of the subsequent material (n) to be extracted from the heating furnace 11 is made to be Tn and an actual result time when the latest material to be started for rolling in the rolling mill No. x is extracted from the heating furnace 11 is made to be T1 , then a presupposed retard period of time hx of the subsequent material to be extracted immediately before the rolling mill No. x is sought through the following equation. -
-
-
- As described above, when the subsequent materials to be extracted are conveyed to the
mills 12 through 16, the calculatingmeans 27 calculates and presupposes the periods of time for awaiting the rolling immediately before themills 12 through 16, i.e. retard periods of time. When the retard periods of time are within the range of allowable values for all of the rolling sills, it is judged that extraction can be made, and when the retard period of time exceeds the allowable retard period of time in any one of the rolling mills, it is judged that extraction cannot be made. - However, when the subsequent material is extracted from the heating furnace 11 as described above, if the extraction cycle time is short, then such a case occurs in the heating furnace 11 that the material is not satisfactorily and uniformly heated, thus causing undesirable influence to the product quality. Then, the calculating means 27 calculates a heating critical cycle time HCT sufficient for applying heat of a predetermined value to the respective materials including the subsequent material to be extracted and the latest material to be extracted, which are present in the heating furnace 11, on the basis of the rolling schedule. More specifically, the calculating means 27 calculates the heating critical cycle time sufficient for applying heat of the predetermined value to the respective materials being present in the heating furnace 11 through the following equation.
-
- Further, when the subsequent material is extracted at the assumed extraction time, the calculating means 27 judges whether or not the aforesaid heating critical cycle time HCT is secured between the subsequent material to be extracted and its preceding material to be extracted. When it is judged that the heating critical cycle time HCT can be secured, the calculating
means 27 transmits the aforesaid assumed extraction time to the heatingfurnace control device 21 as the optimal extraction time for the subsequent material to be extracted. When it is judged that the aforesaid heating critical cycle time HCT is not secured, the calculatingmeans 27 repeats the calculation and presupposition of the respective rolling cycle times MCT, assumption of the extraction time, confirmation of that the presupposed retard period of time is within the allowable retard period of time and confirmation of that the heating critical cycle time can be secured. - In addition, the rolling start signal necessary for determining the rolling cycle times MCT in the
mills 12 through 16 and the subsequent material rolling readiness signal are determined as shown in Table 1. - Figs. 4A and 4B are histograms showing the relationship between the loss time and the number of materials N in the equipment under critical condition in the operating system according to the prior art and in the operating system according to the present invention, respectively, when the materials each having a diameter of 230 mm and a length of 1,535 mm are loaded into the heating furnace in two rows and rolled into steel pipes each having an outer diameter of 273.6 mm, a wall thickness of 6.35 mm and a length of 11,705 mm. As apparent from
- The present invention is applicable not only to the production line for seamless steel pipes in accordance with the Mannessmann-plug mill system but also to the rolling equipment for seamless steel pipes according to the Mandrel mill system, Assel mill system and the like. Further, the present invention is applicable to the rolling equipment for rolling bar steel, wire steel and the like. Furthermore, the present invention is applicable irrespective of the number of rolling mills, and on the contrary, the larger the number of rolling mills is, the greater the effects can be attained.
Claims (1)
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP84104769A EP0159386B1 (en) | 1984-04-27 | 1984-04-27 | Method of controlling mill pacing |
DE8484104769T DE3477475D1 (en) | 1984-04-27 | 1984-04-27 | Method of controlling mill pacing |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP84104769A EP0159386B1 (en) | 1984-04-27 | 1984-04-27 | Method of controlling mill pacing |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0159386A1 true EP0159386A1 (en) | 1985-10-30 |
EP0159386B1 EP0159386B1 (en) | 1989-03-29 |
Family
ID=8191903
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP84104769A Expired EP0159386B1 (en) | 1984-04-27 | 1984-04-27 | Method of controlling mill pacing |
Country Status (2)
Country | Link |
---|---|
EP (1) | EP0159386B1 (en) |
DE (1) | DE3477475D1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN112334242A (en) * | 2019-06-04 | 2021-02-05 | 东芝三菱电机产业系统株式会社 | Rolling rhythm control system |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE1452169B2 (en) * | 1964-11-18 | 1976-02-12 | Nippon Steel Corp., Tokio | CONTROL DEVICE FOR A ROLLING MILL FOR ROLLING HOT STRIP |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS54127812A (en) * | 1978-03-27 | 1979-10-04 | Sumitomo Metal Ind Ltd | Control of heating furnace in mannesmann type pipe production |
-
1984
- 1984-04-27 DE DE8484104769T patent/DE3477475D1/en not_active Expired
- 1984-04-27 EP EP84104769A patent/EP0159386B1/en not_active Expired
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE1452169B2 (en) * | 1964-11-18 | 1976-02-12 | Nippon Steel Corp., Tokio | CONTROL DEVICE FOR A ROLLING MILL FOR ROLLING HOT STRIP |
Non-Patent Citations (1)
Title |
---|
BROWN BOVERI REVIEW, vol. 69, no. 9/10, Sept.-October 1982, Baden, CH; H.G. SCHLATTER "Electrical equipment with microcomputer-aided process control system for a merchant bar and wire rod mill", pages 332-340 * |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN112334242A (en) * | 2019-06-04 | 2021-02-05 | 东芝三菱电机产业系统株式会社 | Rolling rhythm control system |
Also Published As
Publication number | Publication date |
---|---|
EP0159386B1 (en) | 1989-03-29 |
DE3477475D1 (en) | 1989-05-03 |
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