Oily cold rolling mill (CRM) sludge contains lots of iron and alloying elements along with plenty of hazardous organic components, which makes it as an attractive secondary source and an environmental contaminant at...Oily cold rolling mill (CRM) sludge contains lots of iron and alloying elements along with plenty of hazardous organic components, which makes it as an attractive secondary source and an environmental contaminant at the same time. The compound methods of "vacuum distillation + oxidizing roasting" and "vacuum distillation + hydrogen reduction" were employed for the recycle of oily cold rolling mill sludge. First, the sludge was dynamically vacuum distilled in a rotating furnace at 50 r/rain and 600℃ for 3 h, which removed almost hazardous organic components, obtaining 89.2wt% ferrous resultant. Then, high purity ferric oxide powders (99.2wt%) and reduced iron powders (98.9wt%) were obtained when the distillation residues were oxidized and reduced, respectively. The distillation oil can be used for fuel or chemical feedstock, and the distillation gases can be collected and reused as a fuel.展开更多
Electro-hydraulic screw down servo system(HSDS) is widely used in seamless tube rolling mill in western companies.But in Chinese companies,mechanical screw down system(MSDS) is popularly equipped and has a serious...Electro-hydraulic screw down servo system(HSDS) is widely used in seamless tube rolling mill in western companies.But in Chinese companies,mechanical screw down system(MSDS) is popularly equipped and has a serious disadvantage that the roller would often be locked when it is overloaded.For the purpose of designing the first set of domestic twin-roller,four-cylinder and six-framework electro-hydraulic HSDS of seamless tube rolling mill,an experiment system that can simulate the process of seamless tube rolling is constructed.A digital simulation model of the experiment system is built with AMESim software and validated by comparing the simulation results with experiment results.The sudden load response of the screw piston position is studied with the built model and the experiment system.To improve the HSDS's positioning accuracy with large load,a hybrid control scheme of combining load disturbance feedforward compensation(LDFC) method based on servo valve's pressure-stroke feature and anti-saturation integral control(ASIC) is proposed.Both results of simulation and experiment indicate that the transient response time of the single-roller HSDS with the proposed scheme decreases from 0.65 s to less than 0.2 s without static error.To improve the system dynamic stiffness and production qualified rate,a flow rate feedforward compensation(FFC) control strategy based on oil compressibility to dynamic position error is proposed.This FFC strategy is validated with experiments in which the transient error caused by sudden load is reduced to less than 25% of that without FFC.By extending the simulation model to HSDS of a twin-roller,four-cylinder rolling mill,analyzing the mill deformation,and applying the LDFC,ASIC and FFC to the HSDS,the dynamic performance and positioning accuracy of compensated multi-roller HSDS at biting moment are predicted.The research results provide a theoretical and experimental basis for the design of HSDS of seamless steel tube rolling mill.展开更多
Oily cold rolling mill (CRM) sludge is one of the pollutants emitted by iron and steel plants. Recycling oily CRM sludge can not only reduce pollution but also bring social and environmental benefits. In this study,...Oily cold rolling mill (CRM) sludge is one of the pollutants emitted by iron and steel plants. Recycling oily CRM sludge can not only reduce pollution but also bring social and environmental benefits. In this study, using oily CRM sludge as sources of iron oxide, the strontium ferrite powders were synthesized in multiple steps including vacuum distillation, magnetic separation, oxidizing roasting, and solidstate reaction. The optimal technological conditions of vacuum distillation and oxidizing roasting were studied carefully. To consider the effects of Fe203/ SrCO3 tool ratio, calcination temperature, milling time and calcination time on magnetic properties of prepared strontium ferrite powders, the orthogonal experimental method was adopted. The maximum saturation magneti- zation (62.6 mA-m2.g-1) of the synthesized strontium ferrite powders was achieved at the Fe203/SrCO3 mol ratio of 6, 5 h milling time, 1250 ~C calcination temperature, and 1 h calcination time. Strontium ferrite powders syn- thesis method not only provides a cheap, high quality raw material for the production of strontium ferrite powders, but also effectively prevents the environmental pollution.展开更多
Oily cold rolling mill (CRM) sludge is one of metallurgical industry solid wastes. The recycle of these wastes can not only protect the environment but also permit their reutilization. In this research, a new proces...Oily cold rolling mill (CRM) sludge is one of metallurgical industry solid wastes. The recycle of these wastes can not only protect the environment but also permit their reutilization. In this research, a new process of "hydrometallurgical treatment + hydrothermal synthesis" was investigated for the combined recovery of iron and organic materials from oily CRM sludge. Hydrometallurgical treatment, mainly including acid leaching, centrifugal separation, neutralization reaction, oxidizing, and preparation of hydrothermal reaction precursor, was first utilized for processing the sludge. Then, micaceous iron oxide (MIO) pigment powders were prepared through hydrothermal reaction of the obtained precursor in alkaline media. The separated organic materials can be used for fuel or chemical feedstock. The quality of the prepared MIO pigments is in accordance with the standards of MIO pigments for paints (ISO 10601-2007). This clean, effective, and economical technology offers a new way to recycle oily CRM sludge.展开更多
SmartCrown was a new system developed by VAI for improving the strip profile and flatness control first applied in 1700 mm tandem cold rolling mills at Wuhan Iron & Steel (Group) Corporation (WISCO). After tracin...SmartCrown was a new system developed by VAI for improving the strip profile and flatness control first applied in 1700 mm tandem cold rolling mills at Wuhan Iron & Steel (Group) Corporation (WISCO). After tracing and testing, the application of the conventional crown backup roll matching the SmartCrown work roll of the production mill led to heavy and nonuniform wear, and the edge spalling of the backup roll often occurred. A 3-dimension finite element model of roll stacks was established, which was used to analyze the above-mentioned problems, and it was found that the main reason was the highly nonuniform contact pressure distribution between the work roll and the backup roll. A new FSR (flexible shape backup roll) was developed and applied in 1700 mm tandem cold rolling mills. A lot of good actual effects of FSR, such as evident improvement in profile and flatness of strips, non-occurring edge spalling, wear uniform, and remarkable decrease in roll consumption were validated by long-term industrial applications.展开更多
The efficacy of shape control is the core of this technology and the main basis of automatic shape control system model designing. This passage constructs the three-dimensional elastic deformation model of CVCplus rol...The efficacy of shape control is the core of this technology and the main basis of automatic shape control system model designing. This passage constructs the three-dimensional elastic deformation model of CVCplus roll system in 2250 mm hot rolling mill. Comparing and analyzing different influence of working factors on control characteristic, the shape control characteristic of CVCplus roll system in its whole work time is studied, and the cause is analyzed and the difference of the roll gap curve and crown adjustable area in early and latter work time is compared. The outcome has crucial meaning in both theory and production.展开更多
In order to confirm the early failure cause of a four-row cylindrical roller bearing at the backup roll position of a six-high cold sheet mill, its lubrication behavior under harsh operating conditions is investigated...In order to confirm the early failure cause of a four-row cylindrical roller bearing at the backup roll position of a six-high cold sheet mill, its lubrication behavior under harsh operating conditions is investigated. Through establishing and solving the Elastohydrodynamic Lubrication (EHL) model of the roller-inner raceway contact region, the minimum oil film thickness and the real lubrication performance are achieved. The results show the bearing failures come from the poor oil film thickness in the case of high temperature and low rotational speed, which leads to contact wear. So various approaches to improve bearing life via improving lubrication are compared. It has been proved decreasing surface roughness of both contact bodies is an effective way.展开更多
Gear box places an important role rolling mill.Its reliability decides the machine operation.Due to the important role,if the key machine is broken because of gear box′s malfunction,the whole production devices will ...Gear box places an important role rolling mill.Its reliability decides the machine operation.Due to the important role,if the key machine is broken because of gear box′s malfunction,the whole production devices will be influeued.Therefore,it′s very important to monitor the gear box online.Good monitoring system can help companies to better process fault diagnosis.The design sets up a monitoring system with Enwatch polled mode on-line acquisition module and Odyssey software.By calculating the data,the problem of the monitoring system is find,the plans to collect signal is made,the problems of monitoring gear box′s multichannel vibration are solved and the malfunctions initially are estimated according to the signal,which has theoretical basis and practical meanings.展开更多
The load distribution of multi-row bearings of large strip rolling mill is fully analyzed by 3D contact boundary element method (BEM). It is found out that bearings are frequently worn out due to serious uneven load...The load distribution of multi-row bearings of large strip rolling mill is fully analyzed by 3D contact boundary element method (BEM). It is found out that bearings are frequently worn out due to serious uneven load on the multi-row rollers. The constraint mechanism of the previous rolling system is found to be unreasonable by theoretical analysis on heavy machinery structure. A mechanism of self-aligning even load for workroll bearing of 2 050 mm hot rolling mill of Baoshan I&S Co. is developed. This device is manufactured with particular regard to the structure of 2 050 mm hot rolling mill mentioned above. Hence, uneven load on multi-row bearings is greatly relieved and their lives are remarkably prolonged. Meanwhile, theoretical analysis and on-spot tests prove the rationality and validity of the device.展开更多
The unsteady condition of rolling Mill vibration that was caused by flexural vibration of strip was investigated. The parametric flexural vibration equation of rolled strip was established. The parametric flexural vib...The unsteady condition of rolling Mill vibration that was caused by flexural vibration of strip was investigated. The parametric flexural vibration equation of rolled strip was established. The parametric flexural vibration stability of rolled strip was studied and region of stability and unstability was determined based on Floquet theory and perturbation method. The flexural-vibration of strip was unstable if the frequency of variable tension was twice as the natural frequency of flexural-vibration strip. The characteristics of electric current in a temp driving motor’s main loop was studied and tested, and approved that there were 6 humorous current ponderance and 12 humorous current ponderance in main circuit of driving motor. Vertical vibration of working roller was tested, the test approved that there were running unsteady caused by parametric vibration. It attached importance to the parametric vibration of rolling mill.展开更多
Many new types of rolling mills have been studied and developed corresponding to the needs of improvement in productivity and quality.This presentation reflects back at some of the innovative technologies,which were d...Many new types of rolling mills have been studied and developed corresponding to the needs of improvement in productivity and quality.This presentation reflects back at some of the innovative technologies,which were developed by Mitsubishi-Hitachi Metals Machinery,Inc.(hereinafter referred to as M-H),including the evolution of the pair cross mill,mill stabilizing device,on-line roll profiler,shape meter for hot-rolling,endless hot-rolling, recent application of UCM,and M-H split housing type 20-high mill.展开更多
In the Metals Industry,interruption-free processes to produce high-quality end products are a prerequisite. The main drives together with the mill stands play a key role in the success of rolling mills.The crucial dem...In the Metals Industry,interruption-free processes to produce high-quality end products are a prerequisite. The main drives together with the mill stands play a key role in the success of rolling mills.The crucial demands placed on the drive system are:high-dynamic performance of drive and its control system,ability to handle the process related overloads,smooth running,high availability,high efficiency,easy serviceability and ability to integrate seamlessly with the automation systems.With numerous reference installations and many years of experience Siemens VAI has the wider expertise and the portfolio to provide the right drive for every application. This paper examines the latest innovation,SINAMICS drive technology,for both new drive applications as well as for modernizing the existing drives in rolling mill applications like hot strips mills,plate mills,cold rolling mills,and long rolling mills.展开更多
In terms of energy use and carbon footprint,it is the primary processes of ironmaking and steelmaking that command most attention in our industry.The rolling mills,although energy-intensive by comparison with most ind...In terms of energy use and carbon footprint,it is the primary processes of ironmaking and steelmaking that command most attention in our industry.The rolling mills,although energy-intensive by comparison with most industrial finishing operations,are often overlooked when a steel company considers its environmental responsibilities and its energy-saving opportunities. The high gearing of energy consumption of the primary processes over the finishing processes has an important consequence,however.The key to green rolling is as much about yield(and avoiding the remelting of scrap) as it is about direct energy use. This paper uses a project case study,the design and commissioning of the Endless Strip Processing(ESP) plant of Arvedi in Italy to illustrate how modern rolling mills are contributing to a greener steel industry.The relevant technical features include the energy savings implicit in near-net shape casting and in direct rolling,without intermediate reheating,advances in drive and power conversion technologies and the aforementioned concept of energy saving through yield maximisation. Some notable co-operative efforts towards greener rolling are also explained,including university collaborations and in particular the WellMet2050 project at the University of Cambridge.In conclusion,the green credentials of steel usage in general industry are considered and key messages for the engineering community are sought.展开更多
Steel rolling mills have complex processes,specifications,and varieties,along with certain process quality fluctuations and complex production events,making production management decisions difficult.With the developme...Steel rolling mills have complex processes,specifications,and varieties,along with certain process quality fluctuations and complex production events,making production management decisions difficult.With the development of industrial big data technology,several industrial event solutions based on data have been proposed.These solutions are supported by predictive data and remarkably improve the production level.Taking a heavy plate production line as the research object,through scientific calculations based on historical big data,this paper establishes an optimization logic for plan arrangement,forecasts the quality through the stable relationship between data and quality,intelligently optimizes the subsequent process flow,improves the production line capacity,and reduces the process bottlenecks.展开更多
It is studied how the aluminum foil chatter mark is produced and controlled The stableness of hydraulic AGC system,fluid vibration of capsule system,and electromechanical coupling of AC/AC VVVF system and de coupli...It is studied how the aluminum foil chatter mark is produced and controlled The stableness of hydraulic AGC system,fluid vibration of capsule system,and electromechanical coupling of AC/AC VVVF system and de coupling are also studied It is shown that rolling mill design should go to system dynamic design from traditional design The framed drawing of system dynamic design program is presented.展开更多
A web based condition monitoring and fault diagnosis system (CMAFDS) for the F2 finishing mill of the 2050 Hot Strip Mill was developed at a steel works. The features of the condition monitoring and fault diagnosis s...A web based condition monitoring and fault diagnosis system (CMAFDS) for the F2 finishing mill of the 2050 Hot Strip Mill was developed at a steel works. The features of the condition monitoring and fault diagnosis system based on the Web are analyzed in this paper. This paper also describes the main frame of the hardware and the software in the system and emphatically points out the function of the database management system(DBMS) based on the Web. It is proved that the web based CMAFDS is practical in technology and much superior to the CMAFDS based on other network technology in functions.展开更多
The 4-hi cold mill is one of the key wide strip tandem cold rolling mills and has many advantages and characteristics. The mill type is the most important, fundamental and long-term effective factor for the strip shap...The 4-hi cold mill is one of the key wide strip tandem cold rolling mills and has many advantages and characteristics. The mill type is the most important, fundamental and long-term effective factor for the strip shape control. Many advanced mill types such as CVC-4, HCW and PC-4, etc are created based on the conventional four-roll mill. The factors of mill type which affect the deformation of roll system, such as strip width, rolling force, bending force, work roll diameter, backup diameter and so on, arc studied how to affect roll gap crown. It provides a good foundation lbr improving the shape performance of mill.展开更多
Based on the niche genetic algorithm, the intelligent and optimizing model for the rolling force distribution in hot strip mills was put forward. The research showed that the model had many advantages such as fast sea...Based on the niche genetic algorithm, the intelligent and optimizing model for the rolling force distribution in hot strip mills was put forward. The research showed that the model had many advantages such as fast searching speed, high calculating pre- cision and suiting for on-line calculation. A good strip shape could be achieved by using the model and it is appropriate and practica-ble for rolling producing.展开更多
The existing research of the flatness control for strip cold rolling mainly focuses on the calculation of the optimum adjustment of individual flatness actuator in accordance with the flatness deviation, which can be ...The existing research of the flatness control for strip cold rolling mainly focuses on the calculation of the optimum adjustment of individual flatness actuator in accordance with the flatness deviation, which can be used for general flatness control. However, it does not work for some special rolling processes, such as the elimination of ultra single side edge-waves and the prevention of strip break due to tilting roll control overshooting. For the purpose of solving these problems, the influences of non-symmetrical work roll bending and intermediate roll bending on flatness control were analyzed by studying efficiencies of them. Moreover, impacts of two kinds of non-symmetrical roll bending control on the pressure distribution between rolls were studied theoretically. A non-symmetrical work roll bending model was developed by theoretical analysis in accordance with practical conditions. The model was applied to the revamp of a 1250 6-H reversible universal crown mill (UCM) cold mill. Theoretical study and practical applications show that the coordination utilization of the non-symmetrical work roll bending control and tilting roll control was effective in flatness control when there appeared bad strip single side edge waves, especially when the incoming strip was with a wedge shape. In addition, the risk of strip break due to tilting control overshooting could be reduced. Furthermore, the non-symmetrical roll bending control can reduce the extent of uneven distribution of pressure between rolls caused by intermediate roll shifting in flatness control and slow down roll wear. The non-symmetrical roll bending control technology has important theoretical and practical significance to better flatness control.展开更多
基金financially supported by the National Key Technology R&D Program(Nos.2012BAC02B01,2012BAC12B05,2011BAE13B07,and 2011BAC10B02)the National High-Tech Research and Development Program of China(No.2012AA063202)+2 种基金the National Natural Science Foundation of China(Nos.51174247 and51004011)the Science and Technology Program of Guangdong Province,China(No.2010A030200003)the Ph.D.Programs Foundation of the Ministry of Education of China(No.2010000612003)
文摘Oily cold rolling mill (CRM) sludge contains lots of iron and alloying elements along with plenty of hazardous organic components, which makes it as an attractive secondary source and an environmental contaminant at the same time. The compound methods of "vacuum distillation + oxidizing roasting" and "vacuum distillation + hydrogen reduction" were employed for the recycle of oily cold rolling mill sludge. First, the sludge was dynamically vacuum distilled in a rotating furnace at 50 r/rain and 600℃ for 3 h, which removed almost hazardous organic components, obtaining 89.2wt% ferrous resultant. Then, high purity ferric oxide powders (99.2wt%) and reduced iron powders (98.9wt%) were obtained when the distillation residues were oxidized and reduced, respectively. The distillation oil can be used for fuel or chemical feedstock, and the distillation gases can be collected and reused as a fuel.
基金supported by National Natural Science Foundation of China(Grant No.50575156)Open Fund of the State Key Laboratory of Fluid Power Transmission and Control of Zhejiang University,China(Grant No.GZKF-2008006)
文摘Electro-hydraulic screw down servo system(HSDS) is widely used in seamless tube rolling mill in western companies.But in Chinese companies,mechanical screw down system(MSDS) is popularly equipped and has a serious disadvantage that the roller would often be locked when it is overloaded.For the purpose of designing the first set of domestic twin-roller,four-cylinder and six-framework electro-hydraulic HSDS of seamless tube rolling mill,an experiment system that can simulate the process of seamless tube rolling is constructed.A digital simulation model of the experiment system is built with AMESim software and validated by comparing the simulation results with experiment results.The sudden load response of the screw piston position is studied with the built model and the experiment system.To improve the HSDS's positioning accuracy with large load,a hybrid control scheme of combining load disturbance feedforward compensation(LDFC) method based on servo valve's pressure-stroke feature and anti-saturation integral control(ASIC) is proposed.Both results of simulation and experiment indicate that the transient response time of the single-roller HSDS with the proposed scheme decreases from 0.65 s to less than 0.2 s without static error.To improve the system dynamic stiffness and production qualified rate,a flow rate feedforward compensation(FFC) control strategy based on oil compressibility to dynamic position error is proposed.This FFC strategy is validated with experiments in which the transient error caused by sudden load is reduced to less than 25% of that without FFC.By extending the simulation model to HSDS of a twin-roller,four-cylinder rolling mill,analyzing the mill deformation,and applying the LDFC,ASIC and FFC to the HSDS,the dynamic performance and positioning accuracy of compensated multi-roller HSDS at biting moment are predicted.The research results provide a theoretical and experimental basis for the design of HSDS of seamless steel tube rolling mill.
基金supported by the National Key Technology R&D Program (Nos. 2012BAC02B01, 2012BAC12B05, 2011BAE13B07, and 2011BAC10B02)the National High Technology Research and Development Program of China (No. 2012AA063202)+2 种基金the National Natural Science Foundation of China (Nos. 51174247 and 51004011)the Science and Technology Program of Guangdong Province, China (No. 2010A030200003)the Ph.D. Programs Foundation of the Ministry of Education of China (No. 2010000612003)
文摘Oily cold rolling mill (CRM) sludge is one of the pollutants emitted by iron and steel plants. Recycling oily CRM sludge can not only reduce pollution but also bring social and environmental benefits. In this study, using oily CRM sludge as sources of iron oxide, the strontium ferrite powders were synthesized in multiple steps including vacuum distillation, magnetic separation, oxidizing roasting, and solidstate reaction. The optimal technological conditions of vacuum distillation and oxidizing roasting were studied carefully. To consider the effects of Fe203/ SrCO3 tool ratio, calcination temperature, milling time and calcination time on magnetic properties of prepared strontium ferrite powders, the orthogonal experimental method was adopted. The maximum saturation magneti- zation (62.6 mA-m2.g-1) of the synthesized strontium ferrite powders was achieved at the Fe203/SrCO3 mol ratio of 6, 5 h milling time, 1250 ~C calcination temperature, and 1 h calcination time. Strontium ferrite powders syn- thesis method not only provides a cheap, high quality raw material for the production of strontium ferrite powders, but also effectively prevents the environmental pollution.
基金financially supported by the National Key Technology R&D Program of China (Nos.2012BAC02B01,2012BAC12B05,2011BAE13B07,and 2011BAC10B02)the National High-Tech Research and Development Program of China (No.2012AA063202)+2 种基金the National Natural Science Foundation of China (Nos.51174247 and 51004011)the Science and Technology Program of Guangdong Province,China (No.2010A030200003)the Ph.D. Programs Foundation of the Ministry of Education of China (No.2010000612003)
文摘Oily cold rolling mill (CRM) sludge is one of metallurgical industry solid wastes. The recycle of these wastes can not only protect the environment but also permit their reutilization. In this research, a new process of "hydrometallurgical treatment + hydrothermal synthesis" was investigated for the combined recovery of iron and organic materials from oily CRM sludge. Hydrometallurgical treatment, mainly including acid leaching, centrifugal separation, neutralization reaction, oxidizing, and preparation of hydrothermal reaction precursor, was first utilized for processing the sludge. Then, micaceous iron oxide (MIO) pigment powders were prepared through hydrothermal reaction of the obtained precursor in alkaline media. The separated organic materials can be used for fuel or chemical feedstock. The quality of the prepared MIO pigments is in accordance with the standards of MIO pigments for paints (ISO 10601-2007). This clean, effective, and economical technology offers a new way to recycle oily CRM sludge.
文摘SmartCrown was a new system developed by VAI for improving the strip profile and flatness control first applied in 1700 mm tandem cold rolling mills at Wuhan Iron & Steel (Group) Corporation (WISCO). After tracing and testing, the application of the conventional crown backup roll matching the SmartCrown work roll of the production mill led to heavy and nonuniform wear, and the edge spalling of the backup roll often occurred. A 3-dimension finite element model of roll stacks was established, which was used to analyze the above-mentioned problems, and it was found that the main reason was the highly nonuniform contact pressure distribution between the work roll and the backup roll. A new FSR (flexible shape backup roll) was developed and applied in 1700 mm tandem cold rolling mills. A lot of good actual effects of FSR, such as evident improvement in profile and flatness of strips, non-occurring edge spalling, wear uniform, and remarkable decrease in roll consumption were validated by long-term industrial applications.
文摘The efficacy of shape control is the core of this technology and the main basis of automatic shape control system model designing. This passage constructs the three-dimensional elastic deformation model of CVCplus roll system in 2250 mm hot rolling mill. Comparing and analyzing different influence of working factors on control characteristic, the shape control characteristic of CVCplus roll system in its whole work time is studied, and the cause is analyzed and the difference of the roll gap curve and crown adjustable area in early and latter work time is compared. The outcome has crucial meaning in both theory and production.
基金This paper is supported by National Natural Science Fundation of China under Grant No.50405030.
文摘In order to confirm the early failure cause of a four-row cylindrical roller bearing at the backup roll position of a six-high cold sheet mill, its lubrication behavior under harsh operating conditions is investigated. Through establishing and solving the Elastohydrodynamic Lubrication (EHL) model of the roller-inner raceway contact region, the minimum oil film thickness and the real lubrication performance are achieved. The results show the bearing failures come from the poor oil film thickness in the case of high temperature and low rotational speed, which leads to contact wear. So various approaches to improve bearing life via improving lubrication are compared. It has been proved decreasing surface roughness of both contact bodies is an effective way.
文摘Gear box places an important role rolling mill.Its reliability decides the machine operation.Due to the important role,if the key machine is broken because of gear box′s malfunction,the whole production devices will be influeued.Therefore,it′s very important to monitor the gear box online.Good monitoring system can help companies to better process fault diagnosis.The design sets up a monitoring system with Enwatch polled mode on-line acquisition module and Odyssey software.By calculating the data,the problem of the monitoring system is find,the plans to collect signal is made,the problems of monitoring gear box′s multichannel vibration are solved and the malfunctions initially are estimated according to the signal,which has theoretical basis and practical meanings.
基金This project is supported by National Ninth-five Key Technologies R&D Program of China(No.9552801-0201)National Natural Science Foundation of China(No.50575155).
文摘The load distribution of multi-row bearings of large strip rolling mill is fully analyzed by 3D contact boundary element method (BEM). It is found out that bearings are frequently worn out due to serious uneven load on the multi-row rollers. The constraint mechanism of the previous rolling system is found to be unreasonable by theoretical analysis on heavy machinery structure. A mechanism of self-aligning even load for workroll bearing of 2 050 mm hot rolling mill of Baoshan I&S Co. is developed. This device is manufactured with particular regard to the structure of 2 050 mm hot rolling mill mentioned above. Hence, uneven load on multi-row bearings is greatly relieved and their lives are remarkably prolonged. Meanwhile, theoretical analysis and on-spot tests prove the rationality and validity of the device.
文摘The unsteady condition of rolling Mill vibration that was caused by flexural vibration of strip was investigated. The parametric flexural vibration equation of rolled strip was established. The parametric flexural vibration stability of rolled strip was studied and region of stability and unstability was determined based on Floquet theory and perturbation method. The flexural-vibration of strip was unstable if the frequency of variable tension was twice as the natural frequency of flexural-vibration strip. The characteristics of electric current in a temp driving motor’s main loop was studied and tested, and approved that there were 6 humorous current ponderance and 12 humorous current ponderance in main circuit of driving motor. Vertical vibration of working roller was tested, the test approved that there were running unsteady caused by parametric vibration. It attached importance to the parametric vibration of rolling mill.
文摘Many new types of rolling mills have been studied and developed corresponding to the needs of improvement in productivity and quality.This presentation reflects back at some of the innovative technologies,which were developed by Mitsubishi-Hitachi Metals Machinery,Inc.(hereinafter referred to as M-H),including the evolution of the pair cross mill,mill stabilizing device,on-line roll profiler,shape meter for hot-rolling,endless hot-rolling, recent application of UCM,and M-H split housing type 20-high mill.
文摘In the Metals Industry,interruption-free processes to produce high-quality end products are a prerequisite. The main drives together with the mill stands play a key role in the success of rolling mills.The crucial demands placed on the drive system are:high-dynamic performance of drive and its control system,ability to handle the process related overloads,smooth running,high availability,high efficiency,easy serviceability and ability to integrate seamlessly with the automation systems.With numerous reference installations and many years of experience Siemens VAI has the wider expertise and the portfolio to provide the right drive for every application. This paper examines the latest innovation,SINAMICS drive technology,for both new drive applications as well as for modernizing the existing drives in rolling mill applications like hot strips mills,plate mills,cold rolling mills,and long rolling mills.
文摘In terms of energy use and carbon footprint,it is the primary processes of ironmaking and steelmaking that command most attention in our industry.The rolling mills,although energy-intensive by comparison with most industrial finishing operations,are often overlooked when a steel company considers its environmental responsibilities and its energy-saving opportunities. The high gearing of energy consumption of the primary processes over the finishing processes has an important consequence,however.The key to green rolling is as much about yield(and avoiding the remelting of scrap) as it is about direct energy use. This paper uses a project case study,the design and commissioning of the Endless Strip Processing(ESP) plant of Arvedi in Italy to illustrate how modern rolling mills are contributing to a greener steel industry.The relevant technical features include the energy savings implicit in near-net shape casting and in direct rolling,without intermediate reheating,advances in drive and power conversion technologies and the aforementioned concept of energy saving through yield maximisation. Some notable co-operative efforts towards greener rolling are also explained,including university collaborations and in particular the WellMet2050 project at the University of Cambridge.In conclusion,the green credentials of steel usage in general industry are considered and key messages for the engineering community are sought.
文摘Steel rolling mills have complex processes,specifications,and varieties,along with certain process quality fluctuations and complex production events,making production management decisions difficult.With the development of industrial big data technology,several industrial event solutions based on data have been proposed.These solutions are supported by predictive data and remarkably improve the production level.Taking a heavy plate production line as the research object,through scientific calculations based on historical big data,this paper establishes an optimization logic for plan arrangement,forecasts the quality through the stable relationship between data and quality,intelligently optimizes the subsequent process flow,improves the production line capacity,and reduces the process bottlenecks.
基金This project is supported by the 9th Five Year Plan (No-95-528-03-02-03c).
文摘It is studied how the aluminum foil chatter mark is produced and controlled The stableness of hydraulic AGC system,fluid vibration of capsule system,and electromechanical coupling of AC/AC VVVF system and de coupling are also studied It is shown that rolling mill design should go to system dynamic design from traditional design The framed drawing of system dynamic design program is presented.
基金theNationalKeyProjectPlanofChina (GrantNo .PD95 2 190 8)National"973"Project of China (GrantNo .G19880 2 0 32 0 )
文摘A web based condition monitoring and fault diagnosis system (CMAFDS) for the F2 finishing mill of the 2050 Hot Strip Mill was developed at a steel works. The features of the condition monitoring and fault diagnosis system based on the Web are analyzed in this paper. This paper also describes the main frame of the hardware and the software in the system and emphatically points out the function of the database management system(DBMS) based on the Web. It is proved that the web based CMAFDS is practical in technology and much superior to the CMAFDS based on other network technology in functions.
文摘The 4-hi cold mill is one of the key wide strip tandem cold rolling mills and has many advantages and characteristics. The mill type is the most important, fundamental and long-term effective factor for the strip shape control. Many advanced mill types such as CVC-4, HCW and PC-4, etc are created based on the conventional four-roll mill. The factors of mill type which affect the deformation of roll system, such as strip width, rolling force, bending force, work roll diameter, backup diameter and so on, arc studied how to affect roll gap crown. It provides a good foundation lbr improving the shape performance of mill.
文摘Based on the niche genetic algorithm, the intelligent and optimizing model for the rolling force distribution in hot strip mills was put forward. The research showed that the model had many advantages such as fast searching speed, high calculating pre- cision and suiting for on-line calculation. A good strip shape could be achieved by using the model and it is appropriate and practica-ble for rolling producing.
基金supported by National Natural Science Foundation of China (Grant No. 50534020)
文摘The existing research of the flatness control for strip cold rolling mainly focuses on the calculation of the optimum adjustment of individual flatness actuator in accordance with the flatness deviation, which can be used for general flatness control. However, it does not work for some special rolling processes, such as the elimination of ultra single side edge-waves and the prevention of strip break due to tilting roll control overshooting. For the purpose of solving these problems, the influences of non-symmetrical work roll bending and intermediate roll bending on flatness control were analyzed by studying efficiencies of them. Moreover, impacts of two kinds of non-symmetrical roll bending control on the pressure distribution between rolls were studied theoretically. A non-symmetrical work roll bending model was developed by theoretical analysis in accordance with practical conditions. The model was applied to the revamp of a 1250 6-H reversible universal crown mill (UCM) cold mill. Theoretical study and practical applications show that the coordination utilization of the non-symmetrical work roll bending control and tilting roll control was effective in flatness control when there appeared bad strip single side edge waves, especially when the incoming strip was with a wedge shape. In addition, the risk of strip break due to tilting control overshooting could be reduced. Furthermore, the non-symmetrical roll bending control can reduce the extent of uneven distribution of pressure between rolls caused by intermediate roll shifting in flatness control and slow down roll wear. The non-symmetrical roll bending control technology has important theoretical and practical significance to better flatness control.