Application of the new Section XI, A-3000 method for stress intensity factor calculation to thick-walled pressure vessels

Book · Sun Dec 01 04:00:00 EST 1996

OSTI ID:403335

Kendall, D P ^[1]

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1. Kendall (David P.), Troy, NY (United States)

The ASME Boiler and Pressure Vessel Code, Section XI, Appendix A, Article A-3000 has been recently revised to include a more accurate method for calculating stress intensity factors. It is based on fitting the distribution of the stress normal to the plane of the crack in the uncracked body, over the depth of the crack, with a cubic equation. The coefficients of this equation are used with correction factors given in the code to calculate the stress intensity factors at the deepest point of the crack and near the free surface. Correction factors are given for a range of values of relative crack depth and crack shape. In a pressurized thick-walled cylinder the stresses of interest are the tangential stresses due to internal pressure as given by the Lame Equations, plus the effect of the pressure in the crack. This paper shows that the Lame stresses, as a function of distance from the inner surface, can be accurately fitted with a simple set of cubic equations over the full wall thickness for a wide range of diameter ratios. The coefficients of these equations, combined with the correction factors, are used to calculate stress intensity factors for a range of diameter ratios and at both the deepest point of the crack and near the free surface. The results are compared with stress intensity factors calculated using the linearized stress method proposed by Kendall and Perez. The effect of the plastic zone correction given in the new method is reported. The stress intensity factors due to autofrettage residual stresses calculated by the new method are also reported.

• OSTI ID: 403335
• Report Number(s): CONF-960706--; ISBN 0-7918-1782-2
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
CALCULATION METHODS
CRACKS
MATERIALS WORKING
PRESSURE VESSELS
STANDARDS
STRESS ANALYSIS
STRESS INTENSITY FACTORS
THEORETICAL DATA