Stress Intensity Factor of a Corner Crack

2009 ◽  
pp. 477-477-19 ◽  
Author(s):  
AS Kobayashi ◽  
AN Enetanya
Keyword(s):  
Stress Intensity Factor ◽  
Stress Intensity ◽  
Intensity Factor ◽  
Corner Crack

An Investigation of the Stress Intensity Factor Along a Corner Crack in Pressurizer Vent Nozzle Penetration Weld

2009 ◽  
Author(s):  
Sang-Min Lee ◽  
Jeong-Soon Park ◽  
Jin-Su Kim ◽  
Young-Hwan Choi ◽  
Hae-Dong Chung
Keyword(s):  
Stress Intensity Factor ◽  
Stress Intensity ◽  
Fracture Mechanics ◽  
Intensity Factor ◽  
Plastic Zone ◽  
Structural Integrity ◽  
Operating Conditions ◽  
Corner Crack ◽  
Elastic Plastic ◽  
Material Fracture

Elastic-plastic fracture mechanics as well as linear-elastic fracture mechanics may be applied to evaluate a flaw in ferritic low alloy steel components for operating conditions when the material fracture resistance is controlled by upper shelf toughness behavior. In this paper, the distribution of the stress intensity factor along a corner crack using elastic-plastic fracture mechanics technique is investigated to assess the effect of a structural factor on mechanical loads in pressurizer vent nozzle penetration weld. For this purpose, the stress intensity factor and plastic zone correction of a corner crack are calculated under internal pressure, thermal stress and residual stress in accordance with Electric Power Research Institute (EPRI) equation and Irwin’s approach, respectively. The resulting stress intensity factor and plastic zone correction were compared with those obtained from Structural Integrity Associates (SIA) and Kinectrics, and were observed to be good agreement with Kinectrics results.

3-D Elastic Analysis of a Circular Nozzle Corner Crack

1986 ◽  
Vol 108 (4) ◽  
pp. 474-478 ◽  
Author(s):  
W. W. Wilkening
Keyword(s):  
Stress Intensity Factor ◽  
Stress Intensity ◽  
Intensity Factor ◽  
Crack Front ◽  
Pressure Vessel ◽  
Circular Crack ◽  
Elastic Analysis ◽  
Corner Crack ◽  
Linear Elastic ◽  
Circular Nozzle

A 3-D linear elastic analysis has been performed for a circular crack located in the nozzle corner region of a nuclear pressure vessel. The stress intensity factor, K, was found to be virtually constant along the crack front for this particular nozzle corner flaw, which extends one quarter of the distance through the nozzle corner diagonal. The magnitude of K is discussed in relation to the stress intensity factor for the ASME Maximum Postulated Flaw, and is compared to the results of a number of other analyses reported in the literature.

A Residual Stress Analysis of a Corner Crack in Pressurizer Vent Nozzle Penetration Weld

2009 ◽  
Author(s):  
Sang-Min Lee ◽  
Jeong-Soon Park ◽  
Young-Hwan Choi ◽  
Hae-Dong Chung ◽  
Doo-Ho Cho ◽  
...  
Keyword(s):  
Residual Stress ◽  
Stress Intensity Factor ◽  
Stress Intensity ◽  
Intensity Factor ◽  
Plastic Zone ◽  
Welding Process ◽  
Corner Crack ◽  
Dissimilar Metal ◽  
Dissimilar Metal Welding ◽  
Metal Welding

There are some ferritic low alloy steel components including dissimilar metal welding parts in a nuclear power plant. Residual stress induced by welding process is one of the factors that may lead a sound component to have a defect. Therefore it is necessary that the distribution of residual stress is obtained to predict the behavior of a dissimilar metal welding part. In this paper, the distribution of residual stress obtained by finite element analysis is investigated to assess the stress intensity factor of a corner crack in pressurizer vent nozzle penetration weld. Then the stress intensity factor and plastic zone correction of a corner crack are calculated under internal pressure, thermal stress and residual stress in accordance with Electric Power Research Institute equation [1]. The resulting stress intensity factor and plastic-zone correction were compared with those obtained from Structural Integrity Associates.

An Investigation of the Stress Intensity Factor Along a Corner Crack in Pressurizer Vent Nozzle Penetration Weld

2012 ◽  
Vol 134 (3) ◽  
Author(s):  
Sang-Min Lee ◽  
Jeong-Soon Park ◽  
Jin-Su Kim ◽  
Young-Hwan Choi ◽  
Hae-Dong Chung
Keyword(s):  
Stress Intensity Factor ◽  
Stress Intensity ◽  
Fracture Mechanics ◽  
Intensity Factor ◽  
Plastic Zone ◽  
Structural Integrity ◽  
Operating Conditions ◽  
Corner Crack ◽  
Elastic Plastic ◽  
Material Fracture

Elastic–plastic fracture mechanics as well as linear-elastic fracture mechanics may be applied to evaluate a flaw in ferritic low alloy steel components for operating conditions when the material fracture resistance is controlled by upper shelf toughness behavior. In this paper, the distribution of the stress intensity factor (SIF) along a corner crack using elastic–plastic fracture mechanics technique is investigated to assess the effect of a structural factor on mechanical loads in pressurizer vent nozzle penetration weld. For this purpose, the stress intensity factor and the plastic-zone correction of a corner crack are calculated under internal pressure, thermal stress, and residual stress in accordance with Electric Power Research Institute (EPRI) equation and Irwin’s approach, respectively. The resulting stress intensity factor and the plastic-zone correction were compared with those obtained from Structural Integrity Associates (SIA) and Kinectrics Inc., and were observed to be in good agreement with Kinectrics results.

Damage accumulation near a hole under low cycle fatigue proceeding from measurements of local deformation response

2020 ◽  
Vol 86 (10) ◽  
pp. 46-55
Author(s):  
S. I. Eleonsky ◽  
Yu. G. Matvienko ◽  
V. S. Pisarev ◽  
A. V. Chernov
Keyword(s):  
Stress Intensity Factor ◽  
Stress Intensity ◽  
Intensity Factor ◽  
Damage Accumulation ◽  
Stress Ratio ◽  
Low Cycle Fatigue ◽  
Accumulation Process ◽  
Stress Range ◽  
Cycle Fatigue ◽  
Deformation Response

A new destructive method for quantitative determination of the damage accumulation in the vicinity of a stress concentrator has been proposed and verified. Increase of damage degree in local area with a high level of the strain gradient was achieved through preliminary low-cycle pull-push loading of plane specimens with central open holes. The above procedure is performed for three programs at the same stress range (333.3 MPa) and different stress ratio values 0.33, – 0.66 and – 1.0, and vice versa for two programs at the same stress ratio – 0.33 and different stress range 333.3 and 233.3 MPa. This process offers a set of the objects to be considered with different degree of accumulated fatigue damages. The key point of the developed approach consists in the fact that plane specimens with open holes are tested under real operation conditions without a preliminary notching of the specimen initiating the fatigue crack growth. The measured parameters necessary for a quantitative description of the damage accumulation process were obtained by removing the local volume of the material in the form of a sequence of narrow notches at a constant level of external tensile stress. External load can be considered an amplifier enhancing a useful signal responsible for revealing the material damage. The notch is intended for assessing the level of fatigue damage, just as probe holes are used to release residual stress energy in the hole drilling method. Measurements of the deformation response caused by local removing of the material are carried out by electronic speckle-pattern interferometry at different stages of low-cycle fatigue. The transition from measured in-plane displacements to the values of the stress intensity factor (SIF) and the T-stress was carried out on the basis of the relations of linear fracture mechanics. It was shown that the normalized dependences of the stress intensity factor on the durability percentage for the first notch (constructed for four programs of cyclic loading with different parameters), reflect the effect of the stress ratio and stress range of the loading cycle on the rate of damage accumulation. The data were used to obtain the explicit form of the damage accumulation function that quantitatively describes damage accumulation process. The functions were constructed for different stress ratios and stress ranges.

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