高炉热风围管发红、开裂原因分析和处理

针对二铰总厂2#高炉后期热风围管发红、开裂原因进行分析采取专业设备开孔,可调节压力灌浆处理方法使围管温度由原来的500℃-700℃降到250℃以内允许范围内.     

Numerical Analysis of Cylindrical Cavity Expansion in Sand Considering Particle Crushing and Intermediate Principal Stress

Considering the effects of particle crushing and intermediate principal stress on material yielding strength, the spatial mobilization plane(SMP) yielding criterion and state parameter model including a general critical state line are selected in the analysis of cylindrical cavity expansion.Meanwhile, combining Rowe's flow rule and Bolton's simplification to stress-dilatancy relationship to reflect soil shear dilatancy and softening behavior, this paper analyzes the problem of cylindrical cavity expansion i...     

钢板定长剪切生产线PLC控制系统设计

为了便于修改剪切长度和提高剪切精度,提出了一种基于可编程控制器的铜板定长剪切生产线PLC控制系统,并对控制系统的硬件结构和软件组成进行了分析。该系统应用可编程显示器设置剪切长度,采用光电编码器测量钢板长度,采用变频器进行定位控制。生产实践表明,位置控制误差在±1mm以内,同时具有效率高、运行可靠、人机交互友好的特点。     

机加工中刀具材料的应用及发展趋势

强调了机加工中刀具材料选择的重要性,阐述了刀具材料应具备的性能及各种常用的刀具材料的发展、应用现状及特性,并指明了未来刀具材料的发展趋势.     

The effect of high intensity exercise and anticipation on trunk and lower limb biomechanics during a crossover cutting manoeuvre

We investigated the effects of high intensity, intermittent exercise (HIIP) and anticipation on trunk, pelvic and lower limb biomechanics during a crossover cutting manoeuvre. Twenty-eight male, varsity athletes performed crossover cutting manoeuvres in anticipated and unanticipated conditions pre- and post-HIIP. Kinematic and kinetic variables were captured using a motion analysis system. Statistical parametric mapping (repeated-measures ANOVA) was used to identify differences in biomechanical patterns. Results demonstrated that both unanticipation and fatigue (HIIP) altered the biomechanics of the crossover cutting manoeuvre, whereas no interactions effects were observed. Unanticipation resulted in less trunk and pelvic side flexion in the direction of cut (d = 0.70 – 0.79). This led to increased hip abductor and external rotator moments and increased knee extensor and valgus moments with small effects (d = 0.24–0.42), potentially increasing ACL strain. The HIIP resulted in trivial to small effects only with a decrease in internal knee rotator and extensor moment and decreased knee power absorption (d = 0.35), reducing potential ACL strain. The effect of trunk and hip control exercises in unanticipated conditions on the crossover cutting manoeuvre should be investigated with a view to refining ACL injury prevention programmes.     

以解决复杂工程问题为核心的综合切削实验教学改革

为了培养学生识别、分析、解决“复杂工程问题”的能力,分析了“机械制造技术基础”和“公差与技术测量”课程实验目前存在的问题,设计了一个综合切削实验.实验内容包括:确定基于加工质量、效率和成本的切削参数优化模型;根据新型材料的力学性能确定切削参数及其水平;根据田口法设计正交实验方案;利用虚拟仿真实验平台,掌握实验仪器的使用...     

SolidWorks在平面连杆机构动态模拟中的应用

SolidWorks具有几何约束和尺寸驱动等参数化设计功能,且支持鼠标的动态拖动。利用此功能进行平面连杆机构原理性演示时,只用草图状态下的图线就可快速构建机构原型,并实现动态模拟,无需进行繁琐的三维实体造型及装配,也无需进行复杂的编程。