板坯连铸结晶器液压振动系统状态监测试验研究

基于板坯连铸试验平台结晶器液压振动装置,检测不同振动参数下液压缸位移等参数,分析了液压缸位移偏差、相位差随振动参数的变化规律,并讨论了非正弦振动波形的特征。结果表明,液压振动装置实现的结晶器正弦和非正弦振动,具有较高的振动精度,显示出其在结晶器振动方面具有明显的优势。     

连铸结晶器液压振动

弗洛朗热钢铁厂板坯连铸机上安装的结晶器振动装置灵活可靠。该设备能够产生非正弦振动,对于提高板坯皮下纯净度,生产汽车用超低碳钢板具有明显的优势。     

典型板坯连铸机液压振动装置特性分析

通过对典型连铸机液压振动装置的结构特点和特性分析,找出了正弦振动形式和非正弦振动形式主要参数,以及对连铸结晶器拉坯影响的定性和定量关系,根据此定性定量关系指导连铸生产,改善板坯质量,降低生产操作事故,提高铸机的作业水平。     

酒钢结晶器非正弦振动连铸工艺实践

在介绍结晶器振动技术的基础上,针对酒钢1号连铸机结晶器非正弦振动连铸工艺的生产实践,分析其工艺控制参数、振动装置的主要技术指标,分析连铸工艺优化实践和取样结果。生产实践表明,采用非正弦振动,能够通过现场实际情况调整,得到合理的工艺参数,在高拉速条件下获得良好的铸坯表面质量。     

结晶器液压振动台振动状态检测与分析

结晶器振动在连铸生产中具有重要的作用,液压振动是近年来被开发并逐渐推广应用的结晶器振动方式.基于板坯连铸结晶器液压振动装置,通过检测结晶器液压振动装置的位移等参数,对振动系统的振动状态的检测与评价进行试验研究.分析了不同振动参数下两侧液压缸位移偏差、相位差随振动参数的变化规律.结果表明,结晶器液压振动装置具有较高的振动精度.为液压振动条件下结晶器振动状态的检测与评价提供了一种方法.     

连铸机结晶器的液压振动

Ｆｌｏｒａｎｇｅ厂的板坯连铸机上安装的结晶器振动装置非常灵活。该设备能产生非正弦振动，这是使超低碳汽车钢板生产中获得高标准皮下洁净度的决定性改进。     

连铸结晶器混合驱动系统的非正弦振动波形

 针对频率、振幅和波形均可在线调整的连铸结晶器电动式混合驱动系统,提出与其运行模式相匹配的非正弦振动波形。首先阐明新型驱动系统非正弦波形的发生机理;然后按照激波机构的运行特点,考虑系统运行过程中的平稳性和运动约束条件,构建了激波机构的速度函数,进而根据驱动系统运动学推导出以频率、振幅和偏斜率为基本参数的结晶器非正弦振动波形;最后给出非正弦波形的关键工艺参数计算公式,讨论了[vc-f、h]同步控制模型中控制参数与振动工艺参数的关联规律,并以某中碳钢板坯连铸生产为例,利用关联规律,得到了完全符合振动工艺原则的非正弦控制模型,从而验证了该非正弦波形的有效性和实用性。     

结晶器非正弦振动的应用与分析

结晶器是连铸机的最核心设备,结晶器振动形式的选择对于连铸生产与铸坯质量至关重要,本文通过对正弦振动与非正弦振动形式的理论对比分析,得出应用非正弦振动形式的优势及生产实践推广的价值．更有利于改善板坯质量、提高铸机的作业率及设备运行的安全性。     

结晶器非正弦振动技术及其在首钢的开发应用

本文论述了连铸非正弦振动技术的原理及特点,结合首钢生产实际,采用运动叠加的原理,首钢公司和燕山大学合作开发出一种机械驱动的连铸结晶器振动装置,实现了连铸的非正弦振动波形。它同液压伺服系统驱动的非正弦装置相比,具有投资省、操作维护方便等优点。现已应用于首钢第一炼钢厂Ｒ６．５．１２ｍ小板坯连铸机上,运行平稳、可靠,有效降低了铸机的漏钢率,提高了铸坯的表面质量。     

板坯结晶器液压振动同步控制模型的优化设计

针对应用于板坯连铸结晶器液压振动的正弦波形和二阶三角级数非正弦波形,根据保护渣消耗量、振痕深度、振动加速度等重要的限制性因素,以负滑脱时间为基本参考量建立了用于设计结晶器振动同步控制模型的规划求解数学模型,并通过计算获得了各类钢种对应的优化的同步控制模型。另外,基于该优化控制模型对与铸坯质量紧密相关的几个重要的振动工艺参数进行了计算。计算结果表明,本次研究中获得的优化的结晶器振动同步控制模型具有较好的合理性,在浇铸工艺参数（拉速）发生变化时,其相应的振动工艺参数变化较为稳定,这对于铸坯质量来说十分有利,具有良好的冶金效果。     

宽厚板连铸结晶器摩擦行为在线测试与分析

 结晶器/铸坯摩擦行为是影响并决定铸坯表面质量的重要因素。以宽厚板坯连铸结晶器为对象,在线检测基于液压振动装置的结晶器/铸坯摩擦力,测试和分析浇铸温度、铸坯断面、拉速与结晶器振动方式等主要工艺参数对摩擦力的影响,为考察和调控结晶器/铸坯摩擦行为提供试验基础。相同工艺条件下,摩擦力随浇铸温度的升高而降低,随铸坯断面尺寸的增加而增大。正弦、非正弦振动方式与拉速-振频、振幅振动控制模型的合理匹配,能够显著改善高拉速下的结晶器/铸坯摩擦行为,结晶器振动工艺的开发和优化对于充分发挥液压振动装置设备潜力,稳定高拉速下铸坯表面质量具有积极意义。     

Investigation of Friction Force between Mould and Strand Shell under Sinusoidal and Non‐sinusoidal Oscillation in Continuous Slab Casting

Friction force is an important parameter to evaluate powder lubrication and reflect the interaction between mould and strand shell. A non‐sinusoidal oscillation pattern emerges under high speed continuous casting, the characteristic of which is that the time of upward motion is longer than that of the downward motion within one cycle. In the present research experiments were performed on a slab continuous caster with a strand size of 1000 mm ×120 mm. The friction forces of sinusoidal and non‐sinusoidal oscillation under the same parameters were calculated and comparatively analysed. The results show that the friction forces of both oscillation patterns approximately change along with velocity, and present a trend to a trapezoid wave, but there is a phase difference between the friction force and relative velocity. Compared with sinusoidal oscillation, the non‐sinusoidal oscillation pattern exhibits some important advantages as follows; the maximal and average compressive forces and the compressive force work acting on the strand shell are all higher, the maximal tension is lower, and the actual amount of negative strip is higher. These advantages effect better healing of surface cracks and strand demoulds, and reduce the generation and expansion of cracks, consequently improve the surface quality.     

Optimization of Oscillation Model for Slab Continuous Casting Mould Based on Mould Friction Measurements in Plant Trial

Lubrication and friction between the mould and strand are strongly influenced by mould oscillation, and play an important role in slab quality and operating safety during continuous casting processes. Investigation of mould oscillation is therefore essential for getting a better online control of the mould processes. A feasible approach for the development and optimization of mould oscillation was put forward, which combined online measurement of mould friction, design of negative oscillating parameters and evaluation for powder consumption. Three different control models including sinusoidal and non-sinusoidal oscillation for mould oscillations were developed to investigate and evaluate the effects of oscillation on mould friction and powder lubrication. For the purpose of investigating mould friction between mould and strand, online measurement was carried out on a slab continuous caster equipped with a hydraulic oscillator. Also the comparison of the mould friction in sinusoidal and non-sinusoidal mould oscillation was made for subsequent analysis. The industrial experiment result shows that the combination of inverse control model and non-sinusoidal oscillation mode will contribute to the proper powder consumption, leading to a suitable effect of friction force on strand surface, especially for high speed continuous casting. The proposed method provides reliable basis for guiding and optimizing mould oscillation among control models, sinusoidal oscillation and non-sinusoidal oscillation.     

Mould lubrication and friction behaviour with hydraulic oscillators in slab continuous casting

Abstract

It is very important to obtain reliable lubrication from casting powder both at the meniscus and in the gap between strand and mould as it affects slab surface quality and caster productivity. With knowledge of mould friction, a quantitative insight into the behaviour of powder during caster operation is possible. In the present research, the friction was studied based on a slab continuous caster equipped with hydraulic oscillators. The effects of mould oscillation and the abrupt change of casting speed on mould friction force were evaluated, and the characteristics of lubrication behaviour in a casting sequence were investigated. In particular, a comparison between the mould friction force between sinusoidal oscillation mode and non-sinusoidal oscillation mode was made. Finally, the characteristics of friction before a breakout are discussed. The experimental and analytical results may contribute to the development of mould friction online measurement and more clearly learn the lubrication behaviour in different conditions.     

非正弦振动在板坯连铸机上的应用

分析了结晶器非正弦振动的振动特性,介绍了安钢引进的VAI板坯连铸机液压振动的振动特点,讨论了非正弦反向振动的各项振动参数,降低结晶器摩擦阻力、提高保护渣耗量,而且可以在低拉速下保证较低的振痕深度,又能在高拉速下保证操作的安全性。并结合生产实践,指出该振动形式对防止粘结漏钢和改善铸坯表面质量有明显作用。     

连铸结晶器非正弦振动参数及同步控制模型的研究

给出了一种用于连铸生产的非正弦振动波形,并对其波形参数和振动工艺参数进行了讨论。结果表明：这种非正弦振动波形具有较好的拉坯速度适应范围,能够满足连铸生产的要求。另外,还对其波形参数的选择方法进行了探讨,导出了该非正弦振动的同步控制模型。     

Experimental research on effect of control model on lubrication for slab continuous casting mould

Abstract

In casting the control model relation between casting speed and frequency plays an important role in the optimisation of process parameters and the improvement of lubrication condition. The mould friction between mould and strand can directly describe the powder lubrication situation in a mould. In the present research, based on the slab continuous caster equipped with hydraulic oscillators, the transient friction forces were obtained by the differences between the monitored driving forces of casting and the calculated driving forces of no casting at same oscillation parameters. According to the trends of friction force with different control models, the characteristics and disadvantages of the traditional positive control model, and the improved positive control model and the inverse control model are discussed. This experimental study contributes to studying the frictional behaviour in mould under different control models, as well as selecting reasonable control model for high speed continuous casing.     

Transient Mould Friction Based on the Wavelet Theory

The mould friction is an important parameter reflecting the initial shell and mould lubrication conditions.The research of mould friction is very important to the optimization and developing of continuous casting.The measured mould friction under hydraulic oscillation mode was researched with wavelet analysis to reveal its time-frequency characteristics.Firstly,the mould friction signals under different production conditions were monitored and the mould friction was calculated.Then,mother wavelet function was selected from three wavelet functions which were chosen preliminary according to the characteristics of mould friction and wavelet theory.Through wavelet transformation,mould friction signal was projected onto the wavelet domain,and the time-frequency characteristics of mould friction under different production conditions were obtained and discussed.Mould friction under different production conditions such as different oscillation mode,casting speed fluctuation,increasing and decreasing stage of casting speed and breakout occurrence was reported in detail in the wavelet time-frequency maps.The characteristics of mould friction were reflected well through wavelet transformation which proved that wavelet analysis had a good feasibility for mould friction study and can further reveal the nature of mould friction.     

浅谈转炉板坯连铸机结晶器振动系统改造

介绍炼钢厂转炉板坯结晶器原振动系统存在的问题，分析改造理由，提出将振动系统改造为非正弦振动系统的方案。阐述改造后预期达到的效果，对可实现的经济效益进行评估。     

正弦振动结晶器摩擦力与负滑脱参数对比分析

结晶器摩擦力是反映结晶器与铸坯间相互作用、评价保护渣润滑性能的重要参数.由于摩擦力的检测与计算比较复杂,一般通过对振动工艺参数的理论分析来估算结晶器与铸坯间的润滑与摩擦.基于液压振动装置的板坯连铸试验平台,对结晶器摩擦力和振动速度进行了检测实验研究.通过对理论与实测计算结果的对比分析,讨论了结晶器摩擦力状态与负滑脱参数的关系及二者随拉速的变化趋势.该研究在制定适宜的振频-拉速匹配关系、定量理解结晶器与铸坯间的瞬态摩擦行为等方面具有一定的指导作用.