挤压筒应力的动态过程分析

DYNAMIC STRESS ANALYSIS OF EXTRUDING CYLINDER IN EXTRUSION PROCESS

对挤压筒的挤压过程建立了数学模型，并对其受力进行动态分析，查明了挤压过程中内压力作用长度影响筒体受力最危险点的应力变化规律，即当挤压轴行程为整个工作行程的１／３时，挤压筒最危险点应力可为初始应力的４／３倍．这规律也表明了平面应力分析方法与动态分析方法处理计算的差别：采用前者能得出带有普遍意义的静态分析结果；而采用后者，由于考虑了挤压筒内部不同截面应力，故能得出动态变化结果．

By establishing a mathematical model of extrusion process, this paper dynamically analyzed the stress of extruding cylinder during extrusion process and got some rules about the dangerous area and pointed out that when extrusion arm arrives 1/3 of its stroke the stress value at the most dangerous point will get at 4/3 of its original value . This analytical procedure and the conclusions also suggest the differences between the two ways of planar stress analysis and dynamic analysis; the former is a static analysis in the sense of universality, and the latter concerns the change of internal pressure in extruding cylinder during extrusion process. These conclusions can improve the quality of the mechanical optimum design and strength check.