宝钢钢管全浮动芯棒连轧工艺的技术进步

全浮动芯棒连轧管生产线工艺的突出问题是钢管存在“竹节”现象和壁厚均匀度差。围绕提高钢管壁厚均匀度和消除“竹节”现象,进行持续的工艺技术改进,通过改善芯棒润滑条件,自主开发张力减径机非传统孔型,开发大规格孔型和高铬钢产品,提高生产线工艺自动控制水平等,使该生产线继续发挥能力,为用户提供高精度、高钢级的产品。     

气膜片胀形模结构的改进

分析了气膜片零件胀形质量差的原因，对原模具结构进行了改进，解决了原模具成形后贴模不理想、型面不准确的问题，提高了零件质量。     

Cancellation of bulging effect on mould level in continuous casting: Experimental validation

During the continuous casting of steel, several disturbances occur and affect all the parts of the caster, including the mould where the molten steel has to be stable for good quality of the final product. Especially at high casting velocities, the bulging generates important level fluctuations which cannot be efficiently rejected by the classical controllers. To address these problems, this paper proposes an architecture combining disturbances estimation and compensation techniques. It operates as an additional module and does not need any change of the main controller currently implemented. The entire structure has been tested successfully through several simulations and by means of intensive water model experiments.     

板坯连铸铸坯鼓肚变形的仿真研究

合理的控制影响铸坯质量的鼓肚量,有利于铸坯质量的提高。根据板坯实际生产,利用有限元法模拟凝固过程并建立二维热机耦合鼓肚模型,分析了拉速与二冷引起的蠕变时间、坯壳厚度及铸坯温度的变化对鼓肚的影响,为实际生产提供参考。     

胀紧联接套及其在压力机上的应用

介绍一种机械传动基础件——胀紧联接套的工作原理、特点、选用方法及在压力机上的实际应用。     

Validation of a 3D numerical model of shape memory alloys pseudoelasticity through tensile and bulging tests on CuAlBe sheets

In order to validate a 3D numerical model of the pseudoelastic behaviour of shape memory alloys (SMA) allowing a finite-strain analysis, a set of experimental tests is proposed. First consisting in determining the representative elementary volume (REV) model parameters, tensile tests are performed within a small perturbations context. Therefore, two kinds of structure tests representing different stress states are performed: tensile tests on CuAlBe perforated strips on the one hand and bulging tests on CuAlBe sheets on the other hand. With the update of the material parameters for a finite-strain analysis, it is then possible to compare the experimental and the numerical results obtained from tests on structures submitted to general states of stresses. Besides, pictures correlation and infrared thermography analysis have been used and combined to pinpoint the thermomechanical couplings of SMA behaviour.     

ANGULAR DISTORTION ALLOWABLE VALUE AND ASSESS METHOD OF WELD ON COKE TOWER

A graph as the new engineering method for estimate the safety of bulging deformation of coke tower is proposed. Through stresses analysis of circumferential weld of coke tower and comparing the stresses produced by pressure with heat stress of steady state, residual stress, bending stress produced by both itself weight and wind loads, it showed that the stresses produced by pressure on the angle distortion are the main factor of equivalent stress of the combined stress. After comparing four kinds of stress controlling conditions, the relation to stress with depth of angular distortion, grade of curvature of angular distortion and half of region of angular distortion has been inferred. Graph of deformation allowable value of coke tower for different condition by angular distortion and half of region of angular distortion has been plotted. The five steps for its engineering use have been explained. The lighter the grade of curvature is, the larger of bulge allowance, may be, and the bigger of depth of angular distortion may pose too. For the coke tower with a popular structure of Dg 5 400 mm×28 mm, the result by graph is nearly more than the result of two formulas formed by other research, the error is less than 7.0%. But, the graph can be easily applied to different size of angular distortion.     

铝合金板材胀形极限的数值模拟研究

应用韧性断裂准则与有限元数值模拟相结合的方法预测了铝合金板料的胀形极限.将有限元模拟获得板材的应力、应变值代入考虑应力三轴度的Oyane韧性断裂准则进行断裂判断,预测出初始断裂点.准则中的材料常数通过单向拉伸和平面拉伸试验确定.计算了三种铝合金板的半球形凸模胀形极限,计算结果表明,应用Oyane韧性断裂准则能有效地预测铝合金板材的胀形极限.     

基于预变形的静态抗凹性模拟分析

本文用ABAQUS准静态算法对基于胀形预变形试件的静态抗凹性进行了模拟 ,分析了预变形量及板材类型对静态抗凹性能的影响 ,为用数值模拟方法预测和评定覆盖件的抗凹性能积累了可用的经验