无缝气瓶多心凹底底型的设计

Design of Multi-center Concave Bottom for Seamless Cylinder

针对管制无缝气瓶凹底的设计,传统的三心凹底底型在过渡段外表面轮廓线是直线,球壳部分是等厚的球壳。将过渡段原来的直线过渡改为内外两个圆弧过渡,球壳部分设计为厚度变化的球壳,设计出多心凹底底型;运用正交设计方法,定义与设计了多心凹底底型的设计参数;用有限元分析确定各个参数对多圆心凹底底型应力的影响。结果表明,多心凹底气瓶的应力集中程度可以大幅度降低,最低应力集中系数接近于1.1,这对多心凹底气瓶底型设计和加工具有一定的参考价值。

The concave bottom of seamless cylinders has been designed for gas cylinder made from seam- less steel pipe. The contour line of outer surface is a straight line, and the thickness of spherical shell is uniform in traditional three-center geometry design for bottom end-plates of gas cylinders. In this research, a new multi-center concave bottom of gas cylinder was designed by changing the internal and external pro- file of transition section into two arcs with different centers, and using unequal thickness of spherical shell. The design parameters and relationship of the parameters about new bottom were determined by the orthogonal design method. The effects of various parameters on the multi-center concave bottom were ana- lyzed by the finite element method. The results, which are based on finite element analysis of different structure, show that the stress concentration of new bottom can be greatly reduced, and the minimum stress concentration factor is even closed to 1.1. It is valuable for designing and manufacturing the new type of concave bottom.