椭圆封头形状系数的讨论

Discussion on the Stress Intensification Factorsof Ellipsoidal Heads

根据椭圆封头近似椭圆壳的几何形状 ,计算了不同厚径比、不同长短轴之比的椭圆封头的不连续应力 ,得到一组应力增强系数曲线 ,适用于长短轴之比为1～3 5 ,厚径比为0 002～0 04的椭圆封头 .计算表明ASME规范制定椭圆封头形状系数公式时仅考虑厚径比为0 015625时的情况不甚合理 .同时结合厚径比对封头深度的影响 。

Based on the geometry of approximate ellipsoids, the discontinuous stresses of different ratios of thickness to diameter and different length ratios of major to minor axis of ellipsoidal heads are calculated, a group of stress intensification factor curves are obtained The curves may be used for ellipsoidal heads with ratios of thickness to diameter from 0 002 to 0 04, ratios of major to minor axis from 1 0 to 3 5 It is founded that the determination of the factor formula by the ASME, only according to the case of thickness to diameter ratio 0 015625, is not reasonable With the consideration of thickness to diameter ratios on the head depth, minimum allowable depth for ellipsoidal heads with different thickness to diameter ratios are suggested