Effect of the Yield to Tensile Ratio, Y/T, on Structural Reliability of Linepipes

The effect of the Yield (Y) to Tensile (T) ratio, Y/T, on the structural reliability of linepipes with longitudinal defects was studied in this work. A model based on elastic-plastic fracture mechanics (EPFM) and plasticity theory, was developed for that purpose. The analysis allows for load or deformation control situations. The results are shown in terms of curves of critical defect size vs. the controlling variable, i.e. load or deformation. For each one of the several materials studied, different cases with different Y/T values were considered. Even for the lower limits of experimental data, i.e. larger Y/T, the materials have adequate defect tolerance.

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Effect of the Yield to Tensile Ratio on Structural Integrity of Linepipes Subjected to Internal Pressure

Journal of Offshore Mechanics and Arctic Engineering ◽

10.1115/1.2829857 ◽

2011 ◽

Vol 133 (3) ◽

Cited By ~ 1

Author(s):

Hugo A. Ernst ◽

Richard E. Bravo ◽

José A. Villasante ◽

Alfonso Izquierdo

Keyword(s):

Internal Pressure ◽

Structural Integrity ◽

Defect Size ◽

Defect Tolerance ◽

Deformation Control ◽

Critical Defect ◽

Control Situations ◽

Critical Defect Size ◽

T Values ◽

Lower Limits

The effect of the yield (Y) to tensile (T) ratio Y∕T on the structural integrity of linepipes with part through the thickness longitudinal defects subject to internal pressure was studied in this work. A model based on elastic-plastic fracture mechanics and plasticity theory was developed for that purpose. The analysis allows for load or deformation control situations. The results are shown in terms of curves of critical defect size versus the controlling variable, i.e., load or deformation. For each one of the several materials studied, different cases with different Y∕T values were considered. Even for the lower limits of experimental data, i.e., larger Y∕T, the materials have adequate defect tolerance.

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Effect of the Yield to Tensile Ratio, Y/T, on Structural Reliability of Linepipes Subject to Bend Loading

23rd International Conference on Offshore Mechanics and Arctic Engineering, Volume 2 ◽

10.1115/omae2004-51126 ◽

2004 ◽

Author(s):

Hugo A. Ernst ◽

Richard E. Bravo ◽

Jose´ A. Villasante ◽

Alfonso Izquierdo

Keyword(s):

Structural Reliability ◽

Defect Tolerance ◽

Deformation Control ◽

Critical Defect ◽

Control Situations ◽

Critical Defect Size ◽

Circumferential Defects ◽

T Values ◽

Lower Limits ◽

Leak Before Break

A model based on elastic-plastic fracture mechanics (EPFM) and plasticity theory, was developed to study the effect of the Yield (Y) to Tensile (T) ratio, Y/T, on the structural reliability of linepipes with part through the thickness (PTT) circumferential defects subject to bend loading. The analysis allows for load or deformation control situations. The results are shown in terms of curves of critical defect size vs. the controlling variable, i.e. load or deformation. For each one of the materials studied, different cases with different Y/T values were considered. Even for the lower limits of experimental data, i.e. larger Y/T, the materials have adequate defect tolerance. A Leak Before Break Analysis was also conducted.

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Effect of the Yield to Tensile Ratio on Structural Integrity of Line Pipes Subjected to Bending Loads

Journal of Offshore Mechanics and Arctic Engineering ◽

10.1115/1.2948944 ◽

2011 ◽

Vol 133 (3) ◽

Cited By ~ 2

Author(s):

Hugo A. Ernst ◽

Richard E. Bravo

Keyword(s):

Structural Integrity ◽

Defect Tolerance ◽

Deformation Control ◽

Critical Defect ◽

Bending Loads ◽

Critical Defect Size ◽

Circumferential Defects ◽

T Values ◽

Lower Limits ◽

Leak Before Break

This work studies the effect of the yield (Y) to tensile (T) ratio, Y∕T, on the structural integrity of line pipes with part through the thickness (PTT) circumferential defects subject to bend loading. A model based on elastic-plastic fracture mechanics and plasticity theory was developed for that purpose. The analysis handles situation with load or deformation control conditions. The results are shown in terms of curves of critical defect size versus the controlling variable, i.e., load or deformation. For each one of the different materials studied, cases with different Y∕T values were considered. Even for the lower limits of experimental data, i.e., larger Y∕T, the materials have adequate defect tolerance. A leak before break analysis of a PTT circumferential defect growing into a through the thickness defect growing circumferentially was performed.

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Effect of hot isostatic pressing on the critical defect size distribution in AlSi7Mg0.6 alloy obtained by selective laser melting

International Journal of Fatigue ◽

10.1016/j.ijfatigue.2020.105797 ◽

2020 ◽

Vol 140 ◽

pp. 105797

Author(s):

Matthieu Bonneric ◽

Charles Brugger ◽

Nicolas Saintier

Keyword(s):

Size Distribution ◽

Selective Laser Melting ◽

Hot Isostatic Pressing ◽

Defect Size ◽

Laser Melting ◽

Isostatic Pressing ◽

Critical Defect ◽

Critical Defect Size ◽

Defect Size Distribution

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Investigation of the Improvements on Mechanical Properties and Thermal Performance of MgO-MgAl2O4 Composite Refractories by Additions of ZnO-Al2O3 to MgO

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.445.530 ◽

2012 ◽

Vol 445 ◽

pp. 530-535 ◽

Cited By ~ 1

Author(s):

Cemail Aksel

Keyword(s):

Mechanical Properties ◽

Grain Size ◽

Thermal Performance ◽

Industrial Applications ◽

Sem Analysis ◽

Defect Size ◽

Structural Variations ◽

Factors Affecting ◽

Critical Defect ◽

Critical Defect Size

The variations and developments with the reasons on the mechanical properties of MgO-MgAl2O4 and MgO-ZnO-Al2O3 composite refractories were examined and thermal parameters affecting the durability of composites at high temperatures were investigated. The density, porosity, strength, modulus of elasticity, fracture toughness, fracture surface energy, critical defect size and mean MgO grain size values of composites were measured/calculated and evaluated. In addition, microstructural changes using XRD measurements and SEM analysis were examined. Thermal stress/shock parameters R and Rst that are used for determining high temperature performance of composites were calculated. The relationships between mechanical properties and structural variations for different compositions and the factors affecting this connection were investigated. With the additions of various amounts of ZnO-Al2O3 to MgO, significant improvements were achieved on both mechanical properties and R-Rst parameters of in-situ formed M-S-ZnAl2O4 composite refractories, compared to MgO-MgAl2O4 materials containing preformed spinel, by factors of up to 3.6 and 2.0, respectively. The important parameters increasing mechanical properties and thermal performance of M-S-ZnAl2O4 composites were determined as follows: i) formation of ZnAl2O4 phase leading to a high resistance to crack initiation and propagation, ii) propagation of microcracks formed in the structure for a short distance by interlinking to each other, iii) arresting or deviation of microcracks when reaching pores or ZnAl2O4 particles, and additionally iv) co-presence of both intergranular and transgranular types of cracks on fracture surfaces, and with the incorporations of ZnO-Al2O3, v) increase in density, vi) rise in critical defect size, and vii) a significant reduction in MgO grain size. The optimisation of M-S-ZnAl2O4 composite refractories that could be used for obtaining longer service life in industrial applications was performed.

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