... coefficient has a considerable effect on probability of failure of steel pipes with sharp corrosion pits and that the larger the mode I fracture toughness is, the smaller the probability of pipe failure is. pitting corrosion surface cracks steel pipes first passage probability stress intensity...

... analysis is reported for 500 MWe sodium cooled fast reactor (SFR) in this paper. The material of construction is modified 9 Cr-1 Mo and the critical location is the shell nozzle junction. The initial surface crack is postulated at the critical locations at the shell nozzle junction. The critical crack...

... simplify the dynamic finite element analysis in fracture mechanics fields. In this paper, model validation was conducted by comparisons with a series of pipe tests with circumferential through-wall and surface cracks under different excitation conditions. These analyses showed that reasonably accurate...

... for interacting semicircular and semi-elliptical surface cracks by the finite element method under a tensile or bending load. The change in the stress intensity factors and J-integral values due to the relative spacing of cracks was investigated. Based on the relationship between the magnitude of the interaction...

...Masayuki Kamaya The influence of the interaction between two surface cracks on the limit load (LL) was examined by finite element analysis. Circumferential surface cracks were assumed to be on a straight pipe that was subjected to a uniform tensile load. The change in LL due to the relative spacing...

...Toshihisa Nishioka; Guangqin Zhou; Takehiro Fujimoto In nuclear pressure vessels, multiple surface cracks are often found by regular inspection. In order to evaluate the integrity of the vessels, ASME B&PV Code Section XI provides the flaw combination rules; however, its accuracy has not been...

... of Crack Length and Shape During Fracture and Fatigue , C. J. Beavers , ed., Engineering Materials Advisory Services , Cradley Heath, West Midlands, UK , pp. 85 – 284 . Tada , N. , 1992 , “ Monitoring of a Surface Crack in a Finite Body by Means of Electrical Potential Technique...

... to understand the effects of residual stress distribution and the geometry of the component on the stress intensity factor of the surface crack. In this study, the stress intensity factors of surface cracks under two assumed residual stress fields were calculated. As residual stress field, a bending type stress...

...Q. Ma; C. Levy; M. Perl Due to acute temperature gradients and repetitive high-pressure impulses, extremely dense internal surface cracks can be practically developed in highly pressurized thick-walled vessels, typically in gun barrels. In the authors’ previous studies, networks of typical radial...

... up to the limit load. The newly developed analytical approximation of the reference pressure for thick-walled pipes with external axial surface cracks is applicable to a wide range of crack dimensions. The computational model of the considered junction is shown in Fig. 16 . Weld joints are marked...

.... Equivalent CTOD ratio was taken in the failure assessment diagram, and discussed the applicability by comparison with large scale test results of structural component such as edge surface crack panel, center through-wall crack panel, and other geometries. The load ratio L r , cr...

... will be discussed. In addition, the predicted behavior of surface cracks under normal operating conditions (plus welding residual stress) using AFEA will be investigated and compared with the semi-elliptical assumption. Conclusions on the observation of when semi-elliptical flaw assumptions are appropriate...

...A. A. Ali; J. Purbolaksono; A. Khinani; A. Z. Rashid; F. Tarlochan In this paper stress intensity factors of a longitudinal semielliptical surface crack on the inner surface in a compound tube subjected to internal pressure are presented. Variations of modulus of elasticity and thickness...

... computational fluid dynamics corrosion electrochemistry failure (mechanical) film flow flow simulation microfluidics multiphase flow pipe flow pipes surface cracks turbulence wear corrosion dynamic simulation multiphase flow protective films modeling fluid-structure interaction...

... propagation. 03 05 2008 06 05 2009 23 09 2009 alloy steel chromium alloys electron microscopy failure analysis fracture heat exchangers molybdenum alloys optical microscopy pipes surface cracks superheater sensitization buckling steam power boiler Ferritic...

.... The author would like to thank Mr. H. Miyauchi, student of Ibaraki University, for his assistance during the preparation of this paper. 01 05 2008 30 01 2009 22 04 2009 shielding stress analysis surface cracks fitness for service (FFS) rule plastic collapse volumetric flaws...

...C. Levy; M. Perl; S. Kotagiri The influence of the Bauschinger effect (BE) on the three dimensional, Mode I, combined stress intensity factor (SIF) distributions for arrays of longitudinal coplanar, surface cracks emanating from the bore of a fully or partially autofrettaged thick-walled cylinder...

... depth, as well as the preclusion of the load necessary to advance the arrested crack through the RPV wall. a crack depth in the base metal c half-length of a semielliptical surface crack E Young’s modulus of elasticity h stress triaxiality factor, h...

... Characteristic Length ,” J. Mech. Phys. Solids 0022-5096 , 49 , pp. 2921 – 2953 . digital simulation ductile fracture ductility finite element analysis fracture mechanics fracture toughness mechanical engineering computing surface cracks crack tunneling constraint fracture criterion...

...Masayuki Kamaya The interaction between multiple surface cracks is an important consideration in the cracking behavior due to thermal fatigue and stress corrosion cracking. However, it is difficult to evaluate the intensity of the interaction quantitatively because there are many factors...