- Email: [email protected]
The revamping of computer system for WISCO hot strip mill
358
A~tracts
control system, a data highway and a process control computer has been completed for the Tangshen Iron and Steel Company's new No.1 blast furnace. The total system configuration, an outline of the automation system and some considerations in system engineering are described.
steel surface., dummy bar disconnection and gas curing. With one image processor, operational and equipment failures in these areas will be automatically detected in real time. This detection system is qui.'te similar to an artificial visual sense, in that the algorithm for an object to be recognised is automafical]y selected from the imageprocessing result.
087 Approaches to Situation Recognition of Continuous Processes by Time Window and ANN Techniques J. Heidepriem, H. Peters, pp 83-88 This paper discusses the growing interest in recognising, in real time, for continuous processes with slowly varying analog signals, whether the actual situation of the process and/or plant is similar or identical to a former situation. For situation recognition, time series samples from the analog process variables are shifted in discrete steps into a deFmed time window. Three strategies for treating process situations for recognition are presented in the paper. For each strategy different methods of feature extraction and classification exist, including the use of neural networks. Many of these combinations have been investigated by simulations using an artificially defmed synthetic process; some of the results of these simulations are presented here.
088 A Computer Control Systemin Steeimaking with Different Control Strategies and Expert Knowledge LI Jingru, Liu We/, Zhang Zhongjun,
pp 89-93 The paper presents a computer optimization and supervisory control system with a knowledge base for steelmaking in an electric arc furnace (EAF). The designs of the control strategies, hardware and software are included. Three mathematical models are established for the different stages of the steehneking, and three strategies are employed respectively. An expert control strategy is also used for practical use in the steelmaking shop. The system provides a user-friendly interface for the operator. It has been tested in practice and the results are very satisfactory.
089 The Development and Study of Automation Technique for Converter with Top-Bottom Blowing Jiang Shenyan, LI Yusheng, Ba Yanbo, Pen Dehui, Zhao Xinan, En Yi, pp 95-99 The paper presents the study and exploitation of automation techniques related to a converter with topbottom blowing in the 3rd steelmaking plant of the Anshan Iron and Steel Company. The paper discusses the theories, methods and techniques used in modernizing an imported control system, exploiting intelligent modelling, dynamic control of top-bottom blowing techniques, purification of fumes and recovery of coal gas, and the communication connections between the computers in two production systems.
090 Development of Automatic Observation System by Applying Video-Rate Image Processing to
091 Model Mentiflcation for the Mould Level Control Loop in a Continuous Casting Machine F. Kong, R. De Keyser, C. Martien, D. VerhasseR, pp 107-112 A set of measurement insln~rnents was installed in the mould level control of a continuous casting machine. The results showed that the hydraulic system was a nordinear but stable system, and that the larger the peak-to-peak value of the input signal, the higher the natural frequency of the closed-loop hydraulic system. Next, a series of linear models of the components of the level control loop corresponding to various operating conditions was established. These were used to build a computer simulation of the process. The performances of different self-adaptive predictive control methods combined with on-line parameter identification were simulated, investigated and compared with the original PI digital controller.
092 Automation of Mini-Steel Plant and Its Practice Z.W. Ma, Y.G. Li, L.G. Zhou, W.G. Huang, pp 113-117 This paper mainly describes the configuration of the automation system, the mathematical modelling and the management information system for a mini-steel plant in China. Finally, it introduces the results and economic benefits of these automation systems.
093 Advanced Strategies for the Controlled Cooling of Steel P.M. Stone, M.H. Llttlejohn, pp 119-124 This paper examines important issues in designing a controlled cooling strategy to reliably produce higherperformance steel grades. The proposed strategy focuses on making the best use of available information and tools such as process models, measurements of process state, and available filtering, control and diagnostic algorithms. It addresses the issues of temperature measurement and the need for soft sensors, bar cooling control using a process model in open loop, maintenance of model integrity using adaptation techniques, and the incorporation of fault diagnostics. A design for the filter used to predict the initial temperature of the product is outlined and results of simulations using actual mill dam are presented. 094 The Revamping of Computer System for WISCO Hot Strip MIH Liu Jie, Sben Zhongshl, He Deyl,
Zhu Pelyuan, Wang Yafei, Sun Yikang, Xu Haihong, pp 125-131
Steeimaking Process
S. Nalto, T. Shimokasa, Y. Nakashima, T. Yamamoto, C. Itou, K. Tomita, S. Komatsu, T. Tail, pp 101-105 Developed for automatic diagnosis of operations and critical labour-saving in the iron- and steelmaking industry, an operational automatic monitoring system with colour time-series image-processing technology in a continuous casting process has achieved successful recognition rates. Cameras are located in three, monitoring areas: mold hot
The existing computer system of the WISCO hot strip mill, designed in 1974, became unable to meet the need for increased production. It was decided to revamp the computer system with AEG-WestingHouse's WDPF system, using application software written in-house. In December 1991, the software testing of the new system was finished, using rolling simulation. The new computer system has been installed at the field site, and the Pl~reameter tuning of all the APC loops has been completed. new computer system was expected to be put into
,A~tracts
359
operation by October of 1992. This paper introduces the scope of the system revamp and the technical problems encountm'ed.
099 Computer Control System for Treating Process of Ingot Before Blooming Wang Jlao-kuan, Huang Rong-sheng, pp 159-163
095 Automation of the Bao Steel Works Hot Strip Mm D. Lindhoff, Xu Hal Hong, Wang Wen Rul, Zhang Jlan Ping, pp 133-139
The treaunent process of ingots before blooming is an important subprocedure in production in a large iron and steel complex. This paper describes the main design and the architectural c~xfigursfion for realizing computer conuol for the treatment process before blooming in the No.1 Blooming Mill of the Anshan Iron and Steel Complex (AISC).
The automation system of the BAO Steel Hot Strip Mill consists of a four-level computer system (management, production control, process control and basic automation). It is an integrated automation system with all the required functions, from real-time process control to production management, and from product or&n'ing to shipping. It carries out the quality design, monitoring and control according to the end use of the products. In addition, some advanced technological functions have been adopted in the automation system: slab yard management, RAWC, crown and flatness control and hot charge rolling. This paper introduces the lower three levels.
096 Development of High-Accuracy Control System for Hot Strip Mill T. Kato, H. Sekine, T. Kikuchl, Y. Hayasi, T. Kuralshl, pp 141-146
100 New Hot Strip Technology - ChallengeTowards Automation G.K. Uetz, pp 165-168 A reduction of operating costs and investment, and an improvement in the quality of hot strip are made possible only by changing the technology of the production process. The new thin-slab cast-rolling ,t~hnology realises the direct rolling of hot strip in one ~ e a t . For reaching a higher hot-strip quality, besides the usual modem castrolling plant technology, the efficient automation of the entire plant is also necessary. The automation of such modem cast-rolling plants is outlined in the paper. 101 Optimal Scheduling for Hot Ingots W. WaJs, pp 169-173
NKK Keihin Works has developed a high-accuracy control system for the finishing mill in a hot strip mill. Models for the hydraulic screw down and pair cross and shift mill are derived" and a new setup model has been developed. This consists of both thickness control, which includes a gauge meter model, deformation resistance and ~ a t u r e estimation, and crown covaol. To achieve a high-precision model, physical phenomena are described as precisely as possible, and also applied to the on-line computer system. Consequently, the 50 m on-gauge rate has achieved more than 99% in thickness control and the accuracy in terms of strip crown control has also achieved x=l 1 m
The paper concerns operation sequencing control. The time of termination of each operation is conditioned by the solution of the Fourier equation. The aim of the control is the determination of the time at which the change of operation takes place. The change of operation meres a change of boundary condition for the partial differential equation of the parabolic type. Functions describing the boundary conditions are known. The quality criterion for the realization of a sequence of operations is the rain/max of the terms of termination of all operations.
097 Tuning of Process Models Using Artificial Neural Networks and Alternative Methods
102 A New Control System for a Reversing Cold Mill T. Ishibashl, T. Kawabata. T. Ool, E. Yasul, T. Taniguehi, pp 175-180
D. McFarlane, A. Bowles, A. Tsoi, R. MaeNally, pp 147-152 This investigation examines a number of systematic methods for deriving and tuning static process models solely from observed process data. These methods are referred to here as sta6stical modelling; specifically, the use of art~6cia/ neural network (ANN) methods and polynon6al curvefittin& methods for process modelling are considered. An appraisal of the success and failings of each method is given and the methods are compared with a more-conventional physically based modelling approach. 098 GRINDER - An Advisory System for Planning of Grinding Operations J. Lev~n, pp 153-158 A program system, named GRINDER, has been developed for assistance in the planning of grinding operations, and runs on IBM-compatible personal computers. The basis of GRINDER is data stored in a number of tables in a relational data base. These tables contain data describing steel types, grinding wheels, grinding machines, material to be ground, calculation results and experimental data. An operatoz interface is included for easy access to the data in the tables and for easy initiation of calculations, By using regression on stored experiment data GRINDER can be used for the calculation of grinding costs and the optimal setting of grinding parameters.
A new reversing 6-high cold strip mill achieves extremely accurate cold rolling, by using: a fully networked computer control system composed of microcomputers, an accurate mathematical rolling model for set-up control in supervisory computer control, a modified automatic gauge control system (reinforced by the reel torque control system, which includes a strip tension ohservar), and an automatic flatness shape control system, which controls
su~p flatness by utilizing several actuators according to the different types of work roll. On a 0.Smm thick snip, thickness variation can now be conu-oned within 2.5 m and flamess variation can be controlled within 6fiI-unit 103 The Computer System of High Precision Reversible Cold Rolling Mill Tong Chaonan, ZhangHongwet, Wang Jing, Sun Yikang, pp 181-186 This high-precision four-high reversible cold rolfing mill was successfully completed in Shanghai in 1989. The design, manufacture, installation and testing were done through the cooperation between the Shanghai Metallurgic Equipment General Factory and the University of Science and Technology, Beijing. The cold rolling mill is used to produce high-precision cold strip, so it is necessary that the functions and precision of its control system are powerful. In this paper, the functioning of the computez control system is introduced, and the software functions are also
A~tracts
control system, a data highway and a process control computer has been completed for the Tangshen Iron and Steel Company's new No.1 blast furnace. The total system configuration, an outline of the automation system and some considerations in system engineering are described.
steel surface., dummy bar disconnection and gas curing. With one image processor, operational and equipment failures in these areas will be automatically detected in real time. This detection system is qui.'te similar to an artificial visual sense, in that the algorithm for an object to be recognised is automafical]y selected from the imageprocessing result.
087 Approaches to Situation Recognition of Continuous Processes by Time Window and ANN Techniques J. Heidepriem, H. Peters, pp 83-88 This paper discusses the growing interest in recognising, in real time, for continuous processes with slowly varying analog signals, whether the actual situation of the process and/or plant is similar or identical to a former situation. For situation recognition, time series samples from the analog process variables are shifted in discrete steps into a deFmed time window. Three strategies for treating process situations for recognition are presented in the paper. For each strategy different methods of feature extraction and classification exist, including the use of neural networks. Many of these combinations have been investigated by simulations using an artificially defmed synthetic process; some of the results of these simulations are presented here.
088 A Computer Control Systemin Steeimaking with Different Control Strategies and Expert Knowledge LI Jingru, Liu We/, Zhang Zhongjun,
pp 89-93 The paper presents a computer optimization and supervisory control system with a knowledge base for steelmaking in an electric arc furnace (EAF). The designs of the control strategies, hardware and software are included. Three mathematical models are established for the different stages of the steehneking, and three strategies are employed respectively. An expert control strategy is also used for practical use in the steelmaking shop. The system provides a user-friendly interface for the operator. It has been tested in practice and the results are very satisfactory.
089 The Development and Study of Automation Technique for Converter with Top-Bottom Blowing Jiang Shenyan, LI Yusheng, Ba Yanbo, Pen Dehui, Zhao Xinan, En Yi, pp 95-99 The paper presents the study and exploitation of automation techniques related to a converter with topbottom blowing in the 3rd steelmaking plant of the Anshan Iron and Steel Company. The paper discusses the theories, methods and techniques used in modernizing an imported control system, exploiting intelligent modelling, dynamic control of top-bottom blowing techniques, purification of fumes and recovery of coal gas, and the communication connections between the computers in two production systems.
090 Development of Automatic Observation System by Applying Video-Rate Image Processing to
091 Model Mentiflcation for the Mould Level Control Loop in a Continuous Casting Machine F. Kong, R. De Keyser, C. Martien, D. VerhasseR, pp 107-112 A set of measurement insln~rnents was installed in the mould level control of a continuous casting machine. The results showed that the hydraulic system was a nordinear but stable system, and that the larger the peak-to-peak value of the input signal, the higher the natural frequency of the closed-loop hydraulic system. Next, a series of linear models of the components of the level control loop corresponding to various operating conditions was established. These were used to build a computer simulation of the process. The performances of different self-adaptive predictive control methods combined with on-line parameter identification were simulated, investigated and compared with the original PI digital controller.
092 Automation of Mini-Steel Plant and Its Practice Z.W. Ma, Y.G. Li, L.G. Zhou, W.G. Huang, pp 113-117 This paper mainly describes the configuration of the automation system, the mathematical modelling and the management information system for a mini-steel plant in China. Finally, it introduces the results and economic benefits of these automation systems.
093 Advanced Strategies for the Controlled Cooling of Steel P.M. Stone, M.H. Llttlejohn, pp 119-124 This paper examines important issues in designing a controlled cooling strategy to reliably produce higherperformance steel grades. The proposed strategy focuses on making the best use of available information and tools such as process models, measurements of process state, and available filtering, control and diagnostic algorithms. It addresses the issues of temperature measurement and the need for soft sensors, bar cooling control using a process model in open loop, maintenance of model integrity using adaptation techniques, and the incorporation of fault diagnostics. A design for the filter used to predict the initial temperature of the product is outlined and results of simulations using actual mill dam are presented. 094 The Revamping of Computer System for WISCO Hot Strip MIH Liu Jie, Sben Zhongshl, He Deyl,
Zhu Pelyuan, Wang Yafei, Sun Yikang, Xu Haihong, pp 125-131
Steeimaking Process
S. Nalto, T. Shimokasa, Y. Nakashima, T. Yamamoto, C. Itou, K. Tomita, S. Komatsu, T. Tail, pp 101-105 Developed for automatic diagnosis of operations and critical labour-saving in the iron- and steelmaking industry, an operational automatic monitoring system with colour time-series image-processing technology in a continuous casting process has achieved successful recognition rates. Cameras are located in three, monitoring areas: mold hot
The existing computer system of the WISCO hot strip mill, designed in 1974, became unable to meet the need for increased production. It was decided to revamp the computer system with AEG-WestingHouse's WDPF system, using application software written in-house. In December 1991, the software testing of the new system was finished, using rolling simulation. The new computer system has been installed at the field site, and the Pl~reameter tuning of all the APC loops has been completed. new computer system was expected to be put into
,A~tracts
359
operation by October of 1992. This paper introduces the scope of the system revamp and the technical problems encountm'ed.
099 Computer Control System for Treating Process of Ingot Before Blooming Wang Jlao-kuan, Huang Rong-sheng, pp 159-163
095 Automation of the Bao Steel Works Hot Strip Mm D. Lindhoff, Xu Hal Hong, Wang Wen Rul, Zhang Jlan Ping, pp 133-139
The treaunent process of ingots before blooming is an important subprocedure in production in a large iron and steel complex. This paper describes the main design and the architectural c~xfigursfion for realizing computer conuol for the treatment process before blooming in the No.1 Blooming Mill of the Anshan Iron and Steel Complex (AISC).
The automation system of the BAO Steel Hot Strip Mill consists of a four-level computer system (management, production control, process control and basic automation). It is an integrated automation system with all the required functions, from real-time process control to production management, and from product or&n'ing to shipping. It carries out the quality design, monitoring and control according to the end use of the products. In addition, some advanced technological functions have been adopted in the automation system: slab yard management, RAWC, crown and flatness control and hot charge rolling. This paper introduces the lower three levels.
096 Development of High-Accuracy Control System for Hot Strip Mill T. Kato, H. Sekine, T. Kikuchl, Y. Hayasi, T. Kuralshl, pp 141-146
100 New Hot Strip Technology - ChallengeTowards Automation G.K. Uetz, pp 165-168 A reduction of operating costs and investment, and an improvement in the quality of hot strip are made possible only by changing the technology of the production process. The new thin-slab cast-rolling ,t~hnology realises the direct rolling of hot strip in one ~ e a t . For reaching a higher hot-strip quality, besides the usual modem castrolling plant technology, the efficient automation of the entire plant is also necessary. The automation of such modem cast-rolling plants is outlined in the paper. 101 Optimal Scheduling for Hot Ingots W. WaJs, pp 169-173
NKK Keihin Works has developed a high-accuracy control system for the finishing mill in a hot strip mill. Models for the hydraulic screw down and pair cross and shift mill are derived" and a new setup model has been developed. This consists of both thickness control, which includes a gauge meter model, deformation resistance and ~ a t u r e estimation, and crown covaol. To achieve a high-precision model, physical phenomena are described as precisely as possible, and also applied to the on-line computer system. Consequently, the 50 m on-gauge rate has achieved more than 99% in thickness control and the accuracy in terms of strip crown control has also achieved x=l 1 m
The paper concerns operation sequencing control. The time of termination of each operation is conditioned by the solution of the Fourier equation. The aim of the control is the determination of the time at which the change of operation takes place. The change of operation meres a change of boundary condition for the partial differential equation of the parabolic type. Functions describing the boundary conditions are known. The quality criterion for the realization of a sequence of operations is the rain/max of the terms of termination of all operations.
097 Tuning of Process Models Using Artificial Neural Networks and Alternative Methods
102 A New Control System for a Reversing Cold Mill T. Ishibashl, T. Kawabata. T. Ool, E. Yasul, T. Taniguehi, pp 175-180
D. McFarlane, A. Bowles, A. Tsoi, R. MaeNally, pp 147-152 This investigation examines a number of systematic methods for deriving and tuning static process models solely from observed process data. These methods are referred to here as sta6stical modelling; specifically, the use of art~6cia/ neural network (ANN) methods and polynon6al curvefittin& methods for process modelling are considered. An appraisal of the success and failings of each method is given and the methods are compared with a more-conventional physically based modelling approach. 098 GRINDER - An Advisory System for Planning of Grinding Operations J. Lev~n, pp 153-158 A program system, named GRINDER, has been developed for assistance in the planning of grinding operations, and runs on IBM-compatible personal computers. The basis of GRINDER is data stored in a number of tables in a relational data base. These tables contain data describing steel types, grinding wheels, grinding machines, material to be ground, calculation results and experimental data. An operatoz interface is included for easy access to the data in the tables and for easy initiation of calculations, By using regression on stored experiment data GRINDER can be used for the calculation of grinding costs and the optimal setting of grinding parameters.
A new reversing 6-high cold strip mill achieves extremely accurate cold rolling, by using: a fully networked computer control system composed of microcomputers, an accurate mathematical rolling model for set-up control in supervisory computer control, a modified automatic gauge control system (reinforced by the reel torque control system, which includes a strip tension ohservar), and an automatic flatness shape control system, which controls
su~p flatness by utilizing several actuators according to the different types of work roll. On a 0.Smm thick snip, thickness variation can now be conu-oned within 2.5 m and flamess variation can be controlled within 6fiI-unit 103 The Computer System of High Precision Reversible Cold Rolling Mill Tong Chaonan, ZhangHongwet, Wang Jing, Sun Yikang, pp 181-186 This high-precision four-high reversible cold rolfing mill was successfully completed in Shanghai in 1989. The design, manufacture, installation and testing were done through the cooperation between the Shanghai Metallurgic Equipment General Factory and the University of Science and Technology, Beijing. The cold rolling mill is used to produce high-precision cold strip, so it is necessary that the functions and precision of its control system are powerful. In this paper, the functioning of the computez control system is introduced, and the software functions are also