Test of Thick Vessel with a Flaw in Residual Stress Field

Abstract

Intermediate test vessel V-8, a 152-mm-thick vessel fabricated of SA533, grade B, class 1 steel, was pressurized to failure at -23°C. The vessel contained a fatigue-sharpened notch adjacent to a half-bead weld repair that had not been stress relieved. Residual stresses and fracture toughnesses were determined before the pressure test by measurements on a prototypical weld, and fracture predictions were made by linear elastic fracture analysis. Predictions agreed well with test results, demonstrating the important influence of high residual stresses on fracture behavior.

Weld repair practices without post weld heat treatment for ferritic alloys and their consequences on residual stresses: A review

“…All three reported repairs were in accordance to Section XI of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code guidelines. Bryan et al [9] pressurized to failure a vessel of SA533, grade B, class 1 steel, contained a fatigue-sharpened notch adjacent to a halfbead weld repair that had not been stress relieved. Feldstein [10] discussed a supporting EPRI program.…”

The effects of residual macrostresses and microstresses on fatigue crack propagation

“…Theoretical estimates of r p for mode I cracks are given by [26,40] 2 r ϭ ␥(N)* (K / ) [7] p max y where ␥(N) is a material constant that depends on the strainhardening coefficient N (from Eq. Theoretical estimates of r p for mode I cracks are given by [26,40] 2 r ϭ ␥(N)* (K / ) [7] p max y where ␥(N) is a material constant that depends on the strainhardening coefficient N (from Eq.…”

“…[2]) and the stress state (plane stress vs plane strain). [7]. This value was found to be ␥(N ϭ 16) ϭ 0.35 and was then used to calculate r p according to Eq.…”

“…[1][2][3][4][5][6][7] In general, compressive residual stresses are found to decrease FCP rates, while tensile residual stresses produce the opposite effect. In structures undergoing fatigue loading, these residual stresses can alter the local loading conditions and affect fatigue behavior.…”

“…[1,7,23] The plastic deformation generated by the crack tip will form additional residual stresses and may lead to fading of pre-existing residual stresses. [1,7,23] The plastic deformation generated by the crack tip will form additional residual stresses and may lead to fading of pre-existing residual stresses.…”