Prediction of Fracture Toughness Requirement for Pressure Vessels

Based on a two-parameter analysis method of elastic-plastic fracture,a theoretical expression of estimating fracture toughness CTOD requirement has been derived for pressure vessels and other important engineering structures.Provided the fracture toughness of materials in the practical service condition of structures could be prevented.In the expression,stress concentration and residual stresses have been taken into account,and it is indicated that fracture toughness requirement increases with increases with increasing the applied stress and plate thickness.Finally,two practical examples are given to examine the practicality of the theoretical expression.