在过去十年中，分析设计程序的改进使人们更好地理解了“压力容器研究PVRC解释性报告”中“第l节——设计考虑”所述计算应力的重要性基于这些应力考虑，本报告尽可能估计了确保压力容器失效的各种应力相关模式的因素。对于这些失效模式，根据现行规范的容许设计应力和更高的容许设计应力估算安全指数，特别强调高强度钢（抗拉强度高达130000 psi）和基于屈服强度而非抗拉强度的设计。尽管提出了更高设计应力下安全指数的预期变化，但未提出或建议对容许设计应力进行任何变更，因为此类变更是规范的特权和责任- 制造尸体。 对爆破安全指数的分析表明，当容许设计应力基于抗拉强度时，在60000至130000 psi范围内，安全指数随着抗拉强度的增加而增加。然而，对于基于屈服强度的容许设计应力，安全指数随着强度的增加而降低。 延性安全指数很难估计，因为它们取决于破坏模式、双轴或三轴度以及应变集中的大小。对于由剪切机制发生的静态破坏，安全延性指数随着抗拉强度的增加而降低，基于屈服强度的设计低于基于抗拉强度的设计。然而，安全指数似乎足以满足高强度的一次、二次和峰值应变- 钢制压力容器的设计应力高达屈服强度的一半。

Improvements in analytical design procedures developed over the past ten years have led to a better understanding of the significance of calculated stresses as described in "Section l - Design Considerations" of the "PVRC Interpretive Report of Pressure Vessel Research." On the basis of those stress considerations, the present report estimates, insofar as possible, the factors insuring against the various stress-dependent modes of pressure-vessel failures. For these modes of failure, safety indexes are estimated for present Code allowable design stresses and for higher allowable design stresses with particular emphasis on high strength steels (tensile strengths up to 130,000 psi) and on designs based on yield strength rather than tensile strength. Although the expected change in safety indexes for higher design stresses are presented, no changes in the allowable design stresses are proposed or recommended because such changes are the prerogative and responsibility of Code-making bodies. An analysis of the index of safety against bursting indicates that, when the allowable design stress is based on tensile strength, the safety index increases with increased tensile strength in the range 60,000 to 130,000 psi. However, for an allowable design stress based on yield strength, the safety index decreases with increased strength. Ductility safety indexes are difficult to estimate because they depend on the mode of failure, the degree of biaxiality or triaxiality, and the magnitude of strain concentration. For static failures occurring by a shear mechanism, the ductility index of safety decreases with increased tensile strength and is lower for designs based on yield strength than for designs based on tensile strength. Nevertheless, the safety indexes appear adequate for primary, secondary, and peak strains for high strength-steel pressure vessels designed to operate at a stress as high as one-half the yield strength.