In the continuous-casting process, mold-level control is one of the most important factors that ensures the quality of high-efficiency continuous casting slabs. In traditional mold-level prediction control, the mold-level prediction accuracy is low, and the calculation cost is high. In order to improve the prediction accuracy for mold-level prediction, an adaptive hybrid prediction algorithm is proposed. This new algorithm is the combination of empirical mode decomposition (EMD), variational mode decomposition (VMD), and support vector regression (SVR), and it effectively overcomes the impact of noise on the original signal. Firstly, the intrinsic mode functions (IMFs) of the mold-level signal are obtained by the adaptive EMD, and the key parameter of the VMD is obtained by the correlation analysis between the IMFs. VMD is performed based on the key parameter to obtain several IMFs, and the noise IMFs are denoised by wavelet threshold denoising (WTD). Then, SVR is used to predict each denoised component to obtain the predicted IMF. Finally, the predicted mold-level signal is reconstructed by the predicted IMFs. In addition, compared with WTD–SVR and EMD–SVR, VMD–SVR has a competitive advantage against the above three methods in terms of robustness. This new method provides a new idea for mold-level prediction.

通过建立塞棒与浸入式水口的几何位置关系,推导出塞棒的有效行程、连铸机拉速与塞棒开口距离的关系式.根据钢厂实际生产数据,计算出连铸机拉速与塞棒开口距离关系式中的修正系数.结晶器液面控制系统中增加拉速变化预反馈机制可提高动态反馈系统的准确性.

High-quality slab Continuous Casting (CC) production technology is one of the most competitive core technologies in the steel industry. How to inherit and apply the experience of CC expert has become an urgent problem in the quality assurance of CC. First, analyze the demand of the entire CC quality assurance system, carry out the system-based overall design and functional module decomposition design, design the system's workflow. Next, according to the characteristics of different types of knowledge in the field of CC, the representation form of design knowledge, construct the knowledge base of CC field, design the rule reasoning control process in detail according to the functional requirements of the rule inference system, and manage the knowledge base of CC field. Then it designed with maintenance. Finally, the human-computer interaction interface of the system is designed to complete the development of the system, and the detailed function test and analysis of the system's implementation effect are carried out. The system application results show that the system can well represent different types of CC quality assurance knowledge and apply it to systematic reasoning, which can solve the common quality fluctuation problems in CC production process and meet the application requirements. It improves the level of intelligent production of CC, and has certain promotion and reference value for the field of intelligent manufacturing.

本文在总结连铸机设计及研究经验和长期跟踪生产实践的基础上,对凝固末端大压下连铸机的总体技术进行了阐述,研究了连铸机的运转模式、扇形段控制方式和压下控制方式及其之间的相互关系;通过研究机理、推导以及反复计算,确定了各钢种的压下参数并成功运用于生产实践;总结连铸机设计经验提出了新的结晶器窄面上、下口尺寸计算方法;针对液压夹紧扇形段的特点和控制需求提出了简单、准确、可行的扇形段零点标定方法和扇形段刚度测定方法,并通过了生产实践验证.

本文介绍了邯钢大倒角结晶器在线热调宽技术的研发与应用实践.通过对热调宽过程中的工艺参数调宽速度和拉速的理论研究、调宽动作模型的优化以及调宽控制流程的合理设计,实现了大倒角结晶器在线热调宽技术的工程应用.同时也通过实践检验了理论研究的正确性.

A 2D solidification and heat transfer model for the secondary cooling process of beam blank continuous casting was established based on the solidification and heat transfer theory.The 2D space region of the beam blank section was discretized by using the non-equidistant grid,and the heat transfer equations was discretized based on the algorithm of explicit finite difference.The PID control model was established to control beam blank temperature.A dynamic distribution of water control software was developed for secondary cooling process in beam blank continuous casting with Visual Basic 6.0.When the casting speed,pouring temperature and casting steel grade changed,this software might track,record and display the informations of the beam blank in secondary cooling section and dynamically distribute water flow rate for different sections of secondary cooling to maintain the sta—bility of the temperature distribution of the casting blank.This software is of very user-friendly,ver—satile and the simulation results prove that the control effects are desirable.This software lays the foundations for the development of dynamic secondary cooling control system for beam blank.

针对750 mm×450 mm×120 mm异形坯,使用有限元软件建立了铸坯在结晶器内的传热、凝固、收缩及异形坯结晶器铜板热力耦合分析模型.在分析拉速对铸坯收缩、结晶器铜板温度及其变形的影响的基础上,确定了异形坯结晶器铜板的参考锥度,为异形坯结晶器的设计提供参考.

叙述了连铸技术装备的发展现状,举例说明了连铸技术装备精细化及科技创新所取得的成果,进一步指出连铸技术装备的科技创新必须从精细化开始,用事实说明了精细化设计是连铸技术装备科技创新的基础;精细化制造的高质量装备是提高连铸技术装备水平的保证;精细化操作是提高产品质量、提高设备寿命、最大限度发挥设备潜能的关键.得出结论只有坚持精细化,坚持科技创新,才能提升连铸技术装备的发展水平,助推钢铁工业的科技进步.

通过对连铸坯在矫直区的变形分析,提出了一种连铸机多点矫直的矫直辊反力的解析计算法.截取进入第一矫直区间的铸坯段作为隔离体,跟踪其运动,分析其变形,顺次建立该隔离体运动到各个矫直区间时的平衡方程,联立平衡方程求解,就可得到多点矫直各矫直辊上的矫直反力,为矫直辊的设计提供依据.

Based on the theories of integrated design for conticaster,a convenient and efficient visual soft-ware for bloom caster integrated design Billetcastcad was developed with the obj ect-oriented computer language C#.Through the input of basic design premise data,the computation of temperature field,wa-ter allocation,roller layout design and its check can be implemented,and the roller layout graph of the conticaster can also be drawn.The design results from the software are well agreement with the roller layout of casters in operation,meeting practical requirements.

The material and installation way of electrode for pulsed current were investigated.A long-term and high efficiency electrode was designed for applying pulse current on tundish,which was applied on tundish from Shaanxi Longgang company.The results show that the electrode can be used to apply pulse current smoothly and keep the same life cycle with tundish,meanwhile,the working conditions are greatly optimized.

The mold narrow taper change frequently occurs in the mechanical width adjustment mechanism of the mold of the slab continuous caster.The present paper analyzes the origin of the defect and puts up the measures to check it effectively.Since implementation of "up-pull-down-push" method the mold narrow taper changes have been eliminated basically except casually occurrence of 2 mm narrow taper change at the top of the mold in one specific heat and the maximum taper deviation is only 0.2 mm.Practice shows that mold taper deviation can be effectively prevented by adoption of the "up-pull-down-push" method.

The stainless steel slab during production are analyzed.An on-line equipment for cleaning the iron scale and mold fluxes produced on surface of casting slab was developed.The successful application of the equipment proves that the equipment is feasible and reliable for cleaning the surface of casting slabs on line.

Introduces the theory and principle of dynamic soft reduction(DSR) for continuous casting slab(CCS) was introduced,and the key technologies of DSR system were analyzed and studied.The DSR model was built and validated by measuring temperature and shooting nail tests.The DSR system was industrially applied in the continuous caster in China.It is proved that the DSR system runs reliably and the product internal quality remarkably improves.

This paper applied the innovation method TRIZ,defined,analyzed and optimized the question of breaking out during the online mould width adjustment by DAOV flow.Proposed three kinds of scheme through repository query,defined and analyzed the question of breaking out.Through scheme evaluation of optimization phase,selected the third scheme that changes the cast speed of continuous casting machine fast simultaneously changes copper plate taper union as the best scheme to solve the question.Through research of this paper,provide the theory basis to enhance the online mould width adjustment system's security,provided science and highly effective method for the solution related project question.

A model of heat transfer and solidification of continuous cast has been established, including boundary conditions in the mold and spray zones. A finite difference method was used for the numerical simulation. The model calculates the shell thickness and temperature distributions of the slab real time. The importance effect of non-linear material properties of specific heat and thermal conductivity as well as phase changes during solidification is treated. The adequacy of model has been proved by industrial and experimental data. The model can be applied to solve some practical problems in continuous cast.

A new design of on-line mold width adjustment system is described in this paper by an example.The breakout problems in current existing width adjustment system are analyzed and solved by applying TRIZ theory;and it focus on the key operation parameters of the system in studying on quantitatively modeling.Formulas for calculating quantitatively the width adjustment speed and casting speed has been derived,which provides a theoretical basis for safe use of on-line mold width adjustment system.

Starting from the analysis of stresses on narrow side shell, based the principle that the stresses of narrow side shell will be less than the hot strength of cast steel grade, the maximum rate of displacement in course of freely bulging under hydrostatic pressure is deduced in this paper. And the speed of width adjustment is set based on which. Meanwhile the strain on wide side shell in width adjustment process is calculated. According to critical strain hypothesis, after investigation a proper casting speed is set to make the strain of wide side shell less than the critical strain and so to ensure the shell thickness in exit of mold meeting with production requirements.

A two-dimensional (2-D) heat transfer and solidification model has been established and applied to calculate the temperature distribution and solid shell thickness profile of a continuous casting slab in a steel plant. A finite difference method was used for the numerical simulation. For thermal analysis, the 2-D slice unsteady-state heat conduction equation with enthalpy convention was used. Meanwhile, non-linear material properties of specific heat and thermal conductivity as well as phase changes during solidification were considered in the model. The temperature distribution and solid shell thickness calculated by mathematical model agree with those predicted by industrial and experimental measurements. The model could also be used to predict the optimum process parameters on casting speed, heat removal rates and the water distribution of secondary cooling zone.

This paper expatiates the calculation of stream volume according to cooling water and air volume and discusses the selection of fan type.