The multi-phase particle swarm optimization （MPPSO） technique is applied to retrieve the particle size distribution （PSD） under dependent model. Based on the Mie theory and the Lambert-Beer theory, three PSDs, i.e...The multi-phase particle swarm optimization （MPPSO） technique is applied to retrieve the particle size distribution （PSD） under dependent model. Based on the Mie theory and the Lambert-Beer theory, three PSDs, i.e., the Rosin-Rammer （R-R） distribution, the normal distribution, and the logarithmic normal distribution, are estimated by MPPSO algorithm. The results confirm the potential of the proposed approach and show its effectiveness. It may provide a new technique to improve the accuracy and reliability of the PSD inverse calculation.展开更多
原砂的粒度分布是影响型砂的工艺性能及铸件表面质量的重要因素之一.而目前我国铸造行业使用的原砂仍处在自然分布状态,所以生产的铸件表面质量较差,如铸钢件表面粗糙度 Ra 值一般都在50μm-100μm之间.本文探讨了原砂粒度分布对型砂透...原砂的粒度分布是影响型砂的工艺性能及铸件表面质量的重要因素之一.而目前我国铸造行业使用的原砂仍处在自然分布状态,所以生产的铸件表面质量较差,如铸钢件表面粗糙度 Ra 值一般都在50μm-100μm之间.本文探讨了原砂粒度分布对型砂透气性、强度及铸件表面粗糙度的影响.又对级配砂工艺进行了实验研究,把原砂筛分成单筛砂,然后用正交设计法确定各种粒度砂子的最佳加入量.通过实验得出了最佳级配砂比例.利用级配砂浇注的铸钢件可使表面粗糙度Ra 值提高一级,即由50μm-100μm提高到25μm-50μm.展开更多
Many new steel plate processing facilities have been built in the past 10 years around the world with many more being planned for the future.This is especially true in developing countries such as China,India and Braz...Many new steel plate processing facilities have been built in the past 10 years around the world with many more being planned for the future.This is especially true in developing countries such as China,India and Brazil.Many of these facilities are plate mills with either one or two stands or a Steckel mill,typically only one stand designed for the production of structural plate steels.Unfortunately,there is a lack of understanding with both the mill builders of the world and the mill owners on the importance of properly matching up the available slab supply (either new as part of a new plate/Steckel mill complex or part of an already existing) with the desired end plate product mix.Many mill builders and owners around the world believe that you can take any slab of any dimension and make any plate dimension you want.While this is basically true with today’s Level 2 automation systems,it does not always result in optimum metallurgy/mechanical properties or productivity.This less than optimum condition results in mechanical property failures,shape issues,productivity losses and in general a less than desirable costly processing operation.It is important to the overall optimization of a steel processing facility that the proper slab dimensions be used to produce the proper final plate dimensions along with achieving the required mechanical properties.The critical nature of this selection will be dependent on the final plate thickness and overall mechanical property requirements.Proper mechanical property,shape and overall microstructure are heavily dependent on the ability to properly work the entire cross section of the slab through the rolling process.Many mechanical property,shape and microstructural issues are a result of improper working of the entire cross section during rolling.The ability for a given mill to properly work the entire cross section is dependent on proper slab selection (total reduction ratio) and a proper rolling schedule either generated manually by the operator or by the mills Level 2 aut展开更多
基金the National Natural Sci-ence Foundation of China (No.50576019)the Pro-gram for New Century Excellent Talents in University from the Ministry of Education of China.
文摘The multi-phase particle swarm optimization （MPPSO） technique is applied to retrieve the particle size distribution （PSD） under dependent model. Based on the Mie theory and the Lambert-Beer theory, three PSDs, i.e., the Rosin-Rammer （R-R） distribution, the normal distribution, and the logarithmic normal distribution, are estimated by MPPSO algorithm. The results confirm the potential of the proposed approach and show its effectiveness. It may provide a new technique to improve the accuracy and reliability of the PSD inverse calculation.
文摘原砂的粒度分布是影响型砂的工艺性能及铸件表面质量的重要因素之一.而目前我国铸造行业使用的原砂仍处在自然分布状态,所以生产的铸件表面质量较差,如铸钢件表面粗糙度 Ra 值一般都在50μm-100μm之间.本文探讨了原砂粒度分布对型砂透气性、强度及铸件表面粗糙度的影响.又对级配砂工艺进行了实验研究,把原砂筛分成单筛砂,然后用正交设计法确定各种粒度砂子的最佳加入量.通过实验得出了最佳级配砂比例.利用级配砂浇注的铸钢件可使表面粗糙度Ra 值提高一级,即由50μm-100μm提高到25μm-50μm.
文摘Many new steel plate processing facilities have been built in the past 10 years around the world with many more being planned for the future.This is especially true in developing countries such as China,India and Brazil.Many of these facilities are plate mills with either one or two stands or a Steckel mill,typically only one stand designed for the production of structural plate steels.Unfortunately,there is a lack of understanding with both the mill builders of the world and the mill owners on the importance of properly matching up the available slab supply (either new as part of a new plate/Steckel mill complex or part of an already existing) with the desired end plate product mix.Many mill builders and owners around the world believe that you can take any slab of any dimension and make any plate dimension you want.While this is basically true with today’s Level 2 automation systems,it does not always result in optimum metallurgy/mechanical properties or productivity.This less than optimum condition results in mechanical property failures,shape issues,productivity losses and in general a less than desirable costly processing operation.It is important to the overall optimization of a steel processing facility that the proper slab dimensions be used to produce the proper final plate dimensions along with achieving the required mechanical properties.The critical nature of this selection will be dependent on the final plate thickness and overall mechanical property requirements.Proper mechanical property,shape and overall microstructure are heavily dependent on the ability to properly work the entire cross section of the slab through the rolling process.Many mechanical property,shape and microstructural issues are a result of improper working of the entire cross section during rolling.The ability for a given mill to properly work the entire cross section is dependent on proper slab selection (total reduction ratio) and a proper rolling schedule either generated manually by the operator or by the mills Level 2 aut
