TY  - JOUR
AU  - Zelmati, Djamel
AU  - Bouledroua, Omar
AU  - Ghelloudj, Oualid
AU  - Amirat, Abdelaziz
AU  - Đukić, Miloš
PY  - 2022
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/3778
AB  - Considering corrosion rate during the remaining life assessment of aging pipelines is fundamental to calculate the interval between two consecutive inspections. A total of 798 internal and external corrosion defects have been detected, using the Magnetic Flux Leakage intelligent inspection tool, over 48 km of a pipeline length located in the west region of Algeria. The statistical analysis has shown that there is a strong correlation between the corrosion defect length and the corrosion defect circumferential width, with a significant correlation coefficient equal to 82.87%. A probabilistic methodology is presented for the assessment of the remaining life of a corroded pipeline transporting gas, and a finite element method (FEM) was used to assess the pipeline failure pressure. The numerical FEM modeling results were compared with the commonly used codes-models for calculating limit pressure to establish a more realistic and accurate engineering model. The reliability analysis of an API 5L X60 steel made Algerian natural gas pipeline, in service for thirty years, and exposed to active corrosion attack, is presented. The sensitivity analysis of the basic random variables within the nonlinear limit state function was carried out to bring out the relative contribution of each variable affecting the remaining life of corroded pipelines. The reliability analysis is carried out by using Breitung's formula, based on the second-order reliability method (SORM). The reliability assessment of the corroded pipeline is based on the usage of the notched failure assessment diagram (NFAD), different codes for the calculation of the failure pressure, and the numerical results using the finite element analyses (FEA) software ANSYS.
PB  - Elsevier Sci Ltd, Oxford
T2  - Journal of Natural Gas Science and Engineering
T1  - A probabilistic approach to estimate the remaining life and reliability of corroded pipelines
VL  - 99
DO  - 10.1016/j.jngse.2021.104387
ER  - 

@article{
author = "Zelmati, Djamel and Bouledroua, Omar and Ghelloudj, Oualid and Amirat, Abdelaziz and Đukić, Miloš",
year = "2022",
abstract = "Considering corrosion rate during the remaining life assessment of aging pipelines is fundamental to calculate the interval between two consecutive inspections. A total of 798 internal and external corrosion defects have been detected, using the Magnetic Flux Leakage intelligent inspection tool, over 48 km of a pipeline length located in the west region of Algeria. The statistical analysis has shown that there is a strong correlation between the corrosion defect length and the corrosion defect circumferential width, with a significant correlation coefficient equal to 82.87%. A probabilistic methodology is presented for the assessment of the remaining life of a corroded pipeline transporting gas, and a finite element method (FEM) was used to assess the pipeline failure pressure. The numerical FEM modeling results were compared with the commonly used codes-models for calculating limit pressure to establish a more realistic and accurate engineering model. The reliability analysis of an API 5L X60 steel made Algerian natural gas pipeline, in service for thirty years, and exposed to active corrosion attack, is presented. The sensitivity analysis of the basic random variables within the nonlinear limit state function was carried out to bring out the relative contribution of each variable affecting the remaining life of corroded pipelines. The reliability analysis is carried out by using Breitung's formula, based on the second-order reliability method (SORM). The reliability assessment of the corroded pipeline is based on the usage of the notched failure assessment diagram (NFAD), different codes for the calculation of the failure pressure, and the numerical results using the finite element analyses (FEA) software ANSYS.",
publisher = "Elsevier Sci Ltd, Oxford",
journal = "Journal of Natural Gas Science and Engineering",
title = "A probabilistic approach to estimate the remaining life and reliability of corroded pipelines",
volume = "99",
doi = "10.1016/j.jngse.2021.104387"
}

Zelmati, D., Bouledroua, O., Ghelloudj, O., Amirat, A.,& Đukić, M.. (2022). A probabilistic approach to estimate the remaining life and reliability of corroded pipelines. in Journal of Natural Gas Science and Engineering
Elsevier Sci Ltd, Oxford., 99.
https://doi.org/10.1016/j.jngse.2021.104387

Zelmati D, Bouledroua O, Ghelloudj O, Amirat A, Đukić M. A probabilistic approach to estimate the remaining life and reliability of corroded pipelines. in Journal of Natural Gas Science and Engineering. 2022;99.
doi:10.1016/j.jngse.2021.104387 .

Zelmati, Djamel, Bouledroua, Omar, Ghelloudj, Oualid, Amirat, Abdelaziz, Đukić, Miloš, "A probabilistic approach to estimate the remaining life and reliability of corroded pipelines" in Journal of Natural Gas Science and Engineering, 99 (2022),
https://doi.org/10.1016/j.jngse.2021.104387 . .

TY  - JOUR
AU  - Muthanna, Bassam Gamal Nasser
AU  - Bouledroua, Omar
AU  - Meriem-Benziane, Madjid
AU  - Setvati, Mahdi Razavi
AU  - Đukić, Miloš
PY  - 2021
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/3465
AB  - Pipe elbows (bends) are considered critical pressurized components in the piping systems and pipelines due to their stress intensification and the effect of bend curvature. They are prone and hence more exposed to different corrosion failure modes than straight pipes. Late detection of such elbow damages can lead to different dangerous and emergency situations which cause environmental disasters, pollution, substantial consumer losses and a serious threat to human life. A comprehensive safety and reliability assessment of pipe elbows, including usage of prediction models, can provide significant increases in the service life of pipelines. It is well known that the limit pressure is an important parameter to assess the piping integrity. In this paper, the integrity assessment of damaged pipeline elbows made of API 5L X52 steel was done within the framework of numerical modeling using the finite element method (FEM) and finite element analysis (FEA). The evaluation of numerically FEM modeled limit pressure in the corroded elbow containing a rectangular parallelepiped-shaped corrosion defect with rounded corners at the intrados section was done and compared to different codes for calculating limit pressure. Moreover, the area with the corrosion defects with different relative defect depth to wall thickness ratios was FEM modeled at the intrados section of the pipe elbow where the highest hoop stress exists. The results showed that the codes for straight pipes could not be applied for the pipe elbows due to the significantly higher error in the obtained limit pressure value compared with numerically FEM obtained results. However, the results for modified codes, adapted for the pipe elbow case using the Goodall formula for calculation of the hoop stress in pipe elbows with defects are pretty consistent with the numerical FEA results. The notch failure assessment diagram (NFAD) was also used for the straight pipe and pipe bends with different corrosion defect depth ratios, while the obtained critical defect depth ratios further highlighted the criticality of pipe elbows as an essential pipeline component.
PB  - Elsevier Sci Ltd, Oxford
T2  - International Journal of Pressure Vessels and Piping
T1  - Assessment of corroded API 5L X52 pipe elbow using a modified failure assessment diagram
VL  - 190
DO  - 10.1016/j.ijpvp.2020.104291
ER  - 

@article{
author = "Muthanna, Bassam Gamal Nasser and Bouledroua, Omar and Meriem-Benziane, Madjid and Setvati, Mahdi Razavi and Đukić, Miloš",
year = "2021",
abstract = "Pipe elbows (bends) are considered critical pressurized components in the piping systems and pipelines due to their stress intensification and the effect of bend curvature. They are prone and hence more exposed to different corrosion failure modes than straight pipes. Late detection of such elbow damages can lead to different dangerous and emergency situations which cause environmental disasters, pollution, substantial consumer losses and a serious threat to human life. A comprehensive safety and reliability assessment of pipe elbows, including usage of prediction models, can provide significant increases in the service life of pipelines. It is well known that the limit pressure is an important parameter to assess the piping integrity. In this paper, the integrity assessment of damaged pipeline elbows made of API 5L X52 steel was done within the framework of numerical modeling using the finite element method (FEM) and finite element analysis (FEA). The evaluation of numerically FEM modeled limit pressure in the corroded elbow containing a rectangular parallelepiped-shaped corrosion defect with rounded corners at the intrados section was done and compared to different codes for calculating limit pressure. Moreover, the area with the corrosion defects with different relative defect depth to wall thickness ratios was FEM modeled at the intrados section of the pipe elbow where the highest hoop stress exists. The results showed that the codes for straight pipes could not be applied for the pipe elbows due to the significantly higher error in the obtained limit pressure value compared with numerically FEM obtained results. However, the results for modified codes, adapted for the pipe elbow case using the Goodall formula for calculation of the hoop stress in pipe elbows with defects are pretty consistent with the numerical FEA results. The notch failure assessment diagram (NFAD) was also used for the straight pipe and pipe bends with different corrosion defect depth ratios, while the obtained critical defect depth ratios further highlighted the criticality of pipe elbows as an essential pipeline component.",
publisher = "Elsevier Sci Ltd, Oxford",
journal = "International Journal of Pressure Vessels and Piping",
title = "Assessment of corroded API 5L X52 pipe elbow using a modified failure assessment diagram",
volume = "190",
doi = "10.1016/j.ijpvp.2020.104291"
}

Muthanna, B. G. N., Bouledroua, O., Meriem-Benziane, M., Setvati, M. R.,& Đukić, M.. (2021). Assessment of corroded API 5L X52 pipe elbow using a modified failure assessment diagram. in International Journal of Pressure Vessels and Piping
Elsevier Sci Ltd, Oxford., 190.
https://doi.org/10.1016/j.ijpvp.2020.104291

Muthanna BGN, Bouledroua O, Meriem-Benziane M, Setvati MR, Đukić M. Assessment of corroded API 5L X52 pipe elbow using a modified failure assessment diagram. in International Journal of Pressure Vessels and Piping. 2021;190.
doi:10.1016/j.ijpvp.2020.104291 .

Muthanna, Bassam Gamal Nasser, Bouledroua, Omar, Meriem-Benziane, Madjid, Setvati, Mahdi Razavi, Đukić, Miloš, "Assessment of corroded API 5L X52 pipe elbow using a modified failure assessment diagram" in International Journal of Pressure Vessels and Piping, 190 (2021),
https://doi.org/10.1016/j.ijpvp.2020.104291 . .

TY  - JOUR
AU  - Muthanna, Bassam Gamal Nasser
AU  - Bouledroua, Omar
AU  - Meriem-Benziane, Madjid
AU  - Setvati, Mahdi Razavi
AU  - Đukić, Miloš
PY  - 2021
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/3943
AB  - Pipe elbows (bends) are considered critical pressurized components in the piping systems and pipelines due to their stress intensification and the effect of bend curvature. They are prone and hence more exposed to different corrosion failure modes than straight pipes. Late detection of such elbow damages can lead to different dangerous and emergency situations which cause environmental disasters, pollution, substantial consumer losses and a serious threat to human life. A comprehensive safety and reliability assessment of pipe elbows, including usage of prediction models, can provide significant increases in the service life of pipelines. It is well known that the limit pressure is an important parameter to assess the piping integrity. In this paper, the integrity assessment of damaged pipeline elbows made of API 5L X52 steel was done within the framework of numerical modeling using the finite element method (FEM) and finite element analysis (FEA). The evaluation of numerically FEM modeled limit pressure in the corroded elbow containing a rectangular parallelepiped-shaped corrosion defect with rounded corners at the intrados section was done and compared to different codes for calculating limit pressure. Moreover, the area with the corrosion defects with different relative defect depth to wall thickness ratios was FEM modeled at the intrados section of the pipe elbow where the highest hoop stress exists. The results showed that the codes for straight pipes could not be applied for the pipe elbows due to the significantly higher error in the obtained limit pressure value compared with numerically FEM obtained results. However, the results for modified codes, adapted for the pipe elbow case using the Goodall formula for calculation of the hoop stress in pipe elbows with defects are pretty consistent with the numerical FEA results. The notch failure assessment diagram (NFAD) was also used for the straight pipe and pipe bends with different corrosion defect depth ratios, while the obtained critical defect depth ratios further highlighted the criticality of pipe elbows as an essential pipeline component.
PB  - Elsevier Sci Ltd, Oxford
T2  - International Journal of Pressure Vessels and Piping
T1  - Assessment of corroded API 5L X52 pipe elbow using a modified failure assessment diagram
VL  - 190
DO  - 10.1016/j.ijpvp.2020.104291
ER  - 

@article{
author = "Muthanna, Bassam Gamal Nasser and Bouledroua, Omar and Meriem-Benziane, Madjid and Setvati, Mahdi Razavi and Đukić, Miloš",
year = "2021",
abstract = "Pipe elbows (bends) are considered critical pressurized components in the piping systems and pipelines due to their stress intensification and the effect of bend curvature. They are prone and hence more exposed to different corrosion failure modes than straight pipes. Late detection of such elbow damages can lead to different dangerous and emergency situations which cause environmental disasters, pollution, substantial consumer losses and a serious threat to human life. A comprehensive safety and reliability assessment of pipe elbows, including usage of prediction models, can provide significant increases in the service life of pipelines. It is well known that the limit pressure is an important parameter to assess the piping integrity. In this paper, the integrity assessment of damaged pipeline elbows made of API 5L X52 steel was done within the framework of numerical modeling using the finite element method (FEM) and finite element analysis (FEA). The evaluation of numerically FEM modeled limit pressure in the corroded elbow containing a rectangular parallelepiped-shaped corrosion defect with rounded corners at the intrados section was done and compared to different codes for calculating limit pressure. Moreover, the area with the corrosion defects with different relative defect depth to wall thickness ratios was FEM modeled at the intrados section of the pipe elbow where the highest hoop stress exists. The results showed that the codes for straight pipes could not be applied for the pipe elbows due to the significantly higher error in the obtained limit pressure value compared with numerically FEM obtained results. However, the results for modified codes, adapted for the pipe elbow case using the Goodall formula for calculation of the hoop stress in pipe elbows with defects are pretty consistent with the numerical FEA results. The notch failure assessment diagram (NFAD) was also used for the straight pipe and pipe bends with different corrosion defect depth ratios, while the obtained critical defect depth ratios further highlighted the criticality of pipe elbows as an essential pipeline component.",
publisher = "Elsevier Sci Ltd, Oxford",
journal = "International Journal of Pressure Vessels and Piping",
title = "Assessment of corroded API 5L X52 pipe elbow using a modified failure assessment diagram",
volume = "190",
doi = "10.1016/j.ijpvp.2020.104291"
}

Muthanna, B. G. N., Bouledroua, O., Meriem-Benziane, M., Setvati, M. R.,& Đukić, M.. (2021). Assessment of corroded API 5L X52 pipe elbow using a modified failure assessment diagram. in International Journal of Pressure Vessels and Piping
Elsevier Sci Ltd, Oxford., 190.
https://doi.org/10.1016/j.ijpvp.2020.104291

Muthanna BGN, Bouledroua O, Meriem-Benziane M, Setvati MR, Đukić M. Assessment of corroded API 5L X52 pipe elbow using a modified failure assessment diagram. in International Journal of Pressure Vessels and Piping. 2021;190.
doi:10.1016/j.ijpvp.2020.104291 .

Muthanna, Bassam Gamal Nasser, Bouledroua, Omar, Meriem-Benziane, Madjid, Setvati, Mahdi Razavi, Đukić, Miloš, "Assessment of corroded API 5L X52 pipe elbow using a modified failure assessment diagram" in International Journal of Pressure Vessels and Piping, 190 (2021),
https://doi.org/10.1016/j.ijpvp.2020.104291 . .

TY  - JOUR
AU  - Zelmati, Djamel
AU  - Bouledroua, Omar
AU  - Hafsi, Zahreddine
AU  - Đukić, Miloš
PY  - 2020
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/3411
AB  - A methodology is developed in this paper to estimate the time-dependent reliability of a pipeline in Algeria, which is in exploitation from 1981 and with internal and external localized corrosion defects detected in 2009. A probabilistic approach was applied to a pipeline made of API 5L X60 steel for the long-distance transportation of natural gas (55 km), which crossing several geo-graphical reliefs in different country areas. The analysis was carried out by taking into con-sideration the potential stochastic variables altering drastically the reliability of the pipeline, i.e., dimensions of the localized corrosion defects, their locations, and distribution, and the corrosion rate. The correlations between the pipeline spatial corrosion defects distribution and their di-mensions, obtained by using an intelligent inspection tool are used to analyze the actual in-service corrosion attack rate and for enhancement of the accuracy of the reliability assessment. The failure scenario was considered as the moment when the pipeline operating pressure exceeds the failure pressure defined analytically in accordance with different commonly used standards. The assessment of the reliability index of the corroded pipeline subjected to internal pressure and the failure probability was done. The detailed reliability analysis is carried out by using the second order reliability method (SORM) for the basic random variables with different prob-abilistic density within a nonlinear limit state function. The latter is based on the limit analysis of the failure pressure model for different standards and the numerical analysis using the finite element method and ANSYS software.
PB  - Pergamon-Elsevier Science Ltd, Oxford
T2  - Engineering Failure Analysis
T1  - Probabilistic analysis of corroded pipeline under localized corrosion defects based on the intelligent inspection tool
VL  - 115
DO  - 10.1016/j.engfailanal.2020.104683
ER  - 

@article{
author = "Zelmati, Djamel and Bouledroua, Omar and Hafsi, Zahreddine and Đukić, Miloš",
year = "2020",
abstract = "A methodology is developed in this paper to estimate the time-dependent reliability of a pipeline in Algeria, which is in exploitation from 1981 and with internal and external localized corrosion defects detected in 2009. A probabilistic approach was applied to a pipeline made of API 5L X60 steel for the long-distance transportation of natural gas (55 km), which crossing several geo-graphical reliefs in different country areas. The analysis was carried out by taking into con-sideration the potential stochastic variables altering drastically the reliability of the pipeline, i.e., dimensions of the localized corrosion defects, their locations, and distribution, and the corrosion rate. The correlations between the pipeline spatial corrosion defects distribution and their di-mensions, obtained by using an intelligent inspection tool are used to analyze the actual in-service corrosion attack rate and for enhancement of the accuracy of the reliability assessment. The failure scenario was considered as the moment when the pipeline operating pressure exceeds the failure pressure defined analytically in accordance with different commonly used standards. The assessment of the reliability index of the corroded pipeline subjected to internal pressure and the failure probability was done. The detailed reliability analysis is carried out by using the second order reliability method (SORM) for the basic random variables with different prob-abilistic density within a nonlinear limit state function. The latter is based on the limit analysis of the failure pressure model for different standards and the numerical analysis using the finite element method and ANSYS software.",
publisher = "Pergamon-Elsevier Science Ltd, Oxford",
journal = "Engineering Failure Analysis",
title = "Probabilistic analysis of corroded pipeline under localized corrosion defects based on the intelligent inspection tool",
volume = "115",
doi = "10.1016/j.engfailanal.2020.104683"
}

Zelmati, D., Bouledroua, O., Hafsi, Z.,& Đukić, M.. (2020). Probabilistic analysis of corroded pipeline under localized corrosion defects based on the intelligent inspection tool. in Engineering Failure Analysis
Pergamon-Elsevier Science Ltd, Oxford., 115.
https://doi.org/10.1016/j.engfailanal.2020.104683

Zelmati D, Bouledroua O, Hafsi Z, Đukić M. Probabilistic analysis of corroded pipeline under localized corrosion defects based on the intelligent inspection tool. in Engineering Failure Analysis. 2020;115.
doi:10.1016/j.engfailanal.2020.104683 .

Zelmati, Djamel, Bouledroua, Omar, Hafsi, Zahreddine, Đukić, Miloš, "Probabilistic analysis of corroded pipeline under localized corrosion defects based on the intelligent inspection tool" in Engineering Failure Analysis, 115 (2020),
https://doi.org/10.1016/j.engfailanal.2020.104683 . .

TY  - JOUR
AU  - Bouledroua, Omar
AU  - Hafsi, Zahreddine
AU  - Đukić, Miloš
AU  - Elaoud, Sami
PY  - 2020
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/3383
AB  - We are reporting in this study the hydrogen permeation in the lattice structure of a steel pipeline designed for natural gas transportation by investigating the influence of blending gaseous hydrogen into natural gas flow and resulted internal pressure values on the structural integrity of cracked pipes. The presence of cracks may provoke pipeline failure and hydrogen leakage. The auto-ignition of hydrogen leaks, although been small, leads to a flame difficult to be seen. The latter makes such a phenomenon extremely dangerous as explosions became very likely to happen. In this paper, a reliable method is presented that can be used to predict the acceptable defect in order to reduce risks caused by pipe failure due to hydrogen embrittlement. The presented model takes into account the synergistic effects of transient gas flow conditions in pipelines and hydrogen embrittlement of steel material due to pressurized hydrogen gas permeation. It is found that blending hydrogen gas into natural gas pipelines increases the internal load on the pipeline walls due to overpressure values that may be reached in a transient gas flow regime. Also, the interaction between transient hydrogen gas flow and embrittlement of API 5L X52 steel pipeline was investigated using Failure Assessment Diagram (FAD) and the results have shown that transient flow enhances pipeline failure due to hydrogen permeation. It was shown that hydrogen embrittlement of steel pipelines in contact with the hydrogen environment, together with the transient gas flow and significantly increased transient pressure values, also increases the probability of failure of a cracked pipeline. Such a situation threatens the integrity of high stress pipelines, especially under the real working conditions of hydrogen gas transportation.
PB  - Pergamon-Elsevier Science Ltd, Oxford
T2  - International Journal of Hydrogen Energy
T1  - The synergistic effects of hydrogen embrittlement and transient gas flow conditions on integrity assessment of a precracked steel pipeline
EP  - 18020
IS  - 35
SP  - 18010
VL  - 45
DO  - 10.1016/j.ijhydene.2020.04.262
ER  - 

@article{
author = "Bouledroua, Omar and Hafsi, Zahreddine and Đukić, Miloš and Elaoud, Sami",
year = "2020",
abstract = "We are reporting in this study the hydrogen permeation in the lattice structure of a steel pipeline designed for natural gas transportation by investigating the influence of blending gaseous hydrogen into natural gas flow and resulted internal pressure values on the structural integrity of cracked pipes. The presence of cracks may provoke pipeline failure and hydrogen leakage. The auto-ignition of hydrogen leaks, although been small, leads to a flame difficult to be seen. The latter makes such a phenomenon extremely dangerous as explosions became very likely to happen. In this paper, a reliable method is presented that can be used to predict the acceptable defect in order to reduce risks caused by pipe failure due to hydrogen embrittlement. The presented model takes into account the synergistic effects of transient gas flow conditions in pipelines and hydrogen embrittlement of steel material due to pressurized hydrogen gas permeation. It is found that blending hydrogen gas into natural gas pipelines increases the internal load on the pipeline walls due to overpressure values that may be reached in a transient gas flow regime. Also, the interaction between transient hydrogen gas flow and embrittlement of API 5L X52 steel pipeline was investigated using Failure Assessment Diagram (FAD) and the results have shown that transient flow enhances pipeline failure due to hydrogen permeation. It was shown that hydrogen embrittlement of steel pipelines in contact with the hydrogen environment, together with the transient gas flow and significantly increased transient pressure values, also increases the probability of failure of a cracked pipeline. Such a situation threatens the integrity of high stress pipelines, especially under the real working conditions of hydrogen gas transportation.",
publisher = "Pergamon-Elsevier Science Ltd, Oxford",
journal = "International Journal of Hydrogen Energy",
title = "The synergistic effects of hydrogen embrittlement and transient gas flow conditions on integrity assessment of a precracked steel pipeline",
pages = "18020-18010",
number = "35",
volume = "45",
doi = "10.1016/j.ijhydene.2020.04.262"
}

Bouledroua, O., Hafsi, Z., Đukić, M.,& Elaoud, S.. (2020). The synergistic effects of hydrogen embrittlement and transient gas flow conditions on integrity assessment of a precracked steel pipeline. in International Journal of Hydrogen Energy
Pergamon-Elsevier Science Ltd, Oxford., 45(35), 18010-18020.
https://doi.org/10.1016/j.ijhydene.2020.04.262

Bouledroua O, Hafsi Z, Đukić M, Elaoud S. The synergistic effects of hydrogen embrittlement and transient gas flow conditions on integrity assessment of a precracked steel pipeline. in International Journal of Hydrogen Energy. 2020;45(35):18010-18020.
doi:10.1016/j.ijhydene.2020.04.262 .

Bouledroua, Omar, Hafsi, Zahreddine, Đukić, Miloš, Elaoud, Sami, "The synergistic effects of hydrogen embrittlement and transient gas flow conditions on integrity assessment of a precracked steel pipeline" in International Journal of Hydrogen Energy, 45, no. 35 (2020):18010-18020,
https://doi.org/10.1016/j.ijhydene.2020.04.262 . .