Q235A热轧带钢冷弯开裂原因分析

Q235A热轧带钢在冷弯时出现开裂,采用扫描电镜和金相显微镜等对开裂件和合格件进行了观察,结果表明冷弯开裂试样的夹杂物、带状组织级别较高;分析认为夹杂物较多、带状组织级别较高是产生冷弯开裂的主要原因.     

汽轮机轴弯曲故障的诊断和处理

包钢热电厂6^#汽动鼓风机组在一次检修过程中，由于汽轮机提前揭缸造成汽轮机转子轴弯曲，从而引起机组运行过程中振动值偏大。主要介绍了针对该故障的诊断方法和处理过程。     

改善辊型降低弯辊力提高工作辊轴承及轧辊使用寿命

论述了四辊可逆板带冷轧机较大的弯辊力对昂贵的轧辊及轧辊轴承使用寿命的影响,通过研究辊系的弹性变形曲线,找出合理辊系凸度曲线来降低弯辊力.     

Bending and Stability of a Glued Curvilinear Rod with Initial Irregularities

A differential equation has been derived for the bending of a glued curvilinear rod with initial deflections of its elements. Adhesive joints work in shear. The 2D stability, collapse and buckling are investigated for a jointed rod, and the formulas are derived to determine the critical values of its element parameters. Some separate cases are considered and examples are given. __________ Translated from Problemy Prochnosti, No. 6, pp. 114 – 123, November – December, 2005.     

共析钢中片层状渗碳体冷轧后的形态变化

The pearlitic transformation and the deformation behavior of lamellar cementite after cold rolling in eutectoid steels Fe-0. 76%C-0. 137%Mn (mass fraction) were studied by means of Formastor-F (Full Automatic Transformation Testing Instrument) and field emission scanning electronic microscopy (FESEM) observation. Fine and coarse pearlite were obtained in the eutectoid steels austenitized at 900℃ for 15min, then hold at 620℃ for 90 s and 690℃ for 7 h, respectively. Thedeformation behavior of cold rolled lamellar cementite could be classified as: cleavage fracture, inhomogeneous slip, fragmentation, thinning or necking, and homogeneous bending. The cementite lamellae with the thickness of more than 100 um could be deformed plastically.     

An Evaluation of Digital Image Correlation Criteria for Strain Mapping Applications

Abstract:  The performance of four digital image correlation criteria widely used in strain mapping applications has been critically examined using three sets of digital images with various whole-field deformation characteristics. The deformed images in these image sets are digitally modified to simulate the less-than-ideal image acquisition conditions in an actual experiment, such as variable brightness, contrast, uneven local lighting and blurring. The relative robustness, computational cost and reliability of each criterion are assessed for precision strain mapping applications. Recommendations are given for selecting a proper image correlation criterion to efficiently extract reliable deformation data from a given set of digital images.     

等截面塔设备风弯矩的积分求法

由于风压高度变化系数和风压脉动系数沿塔高连续变化，因此，可利用积分求解方法得出等截面塔设备风弯矩计算公式。该公式便于计算机编程，简化了塔设备的强度设计，并且能够验证传统计算方法的结果。     

具有构造措施的高层砖砌体房屋抗震性能试验研究

通过对9层砖砌体结构抗震性能试验,研究了7度地震设防区建筑9层砖砌体结构的可行性,说明了钢筋混凝土构造柱、圈梁及配筋砌体在抗震中的重要作用,指出具有构造措施的9层砖砌体结构在地震作用下的破坏机理为弯曲破坏.     

Evolutionary path planning for robot assisted part handling in sheet metal bending

While the bending sequence planning has been intensively studied, design of the motion path of a sheet metal part in the bending operation tends to be ignored by researchers. Because during the bending operation, the space for maneuvering a sheet metal part is very small, collisions between the part and bending tools are likely to occur. When a robot is used to handle the part, the role of an automatic path-planning tool becomes more significant. In this study, an evolutionary path-planning approach for robot-assisted handling of sheet metal parts in bending is firstly proposed and implemented. The proposed approach globally searches the motion path space to identify feasible paths. Collision detection algorithms based on segment intersection are used to check if the generated paths are feasible or infeasible. This method can automatically design feasible handling operations for a robot. Simulation examples on a simple “V” shaped part and a part with multiple bents demonstrate that the approach is efficient and practical.     

力矩分配法计算超静定结构成果校核方法研究

文章对力矩分配法计算超静定结构的成果校核方法作了探讨与研究，确保最后结果弯矩的正确性。