TY  - CONF
AU  - Međo, Bojan
AU  - Rakin, Marko
AU  - Gubeljak, Nenad
AU  - Musraty, Walid
AU  - Matvienko, Y.
AU  - Milošević, M.
AU  - Sedmak, Aleksandar
PY  - 2017
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/3483
AB  - Integrity of cylindrical structures, such as pipes and small-scale pressure vessels, is typically assessed by testing fracture mechanics specimens, like compact tensile CT or single-edge notched bending, SENB. However, their fabrication is mainly not possible for thin-walled pressurised elements, commonly used in structures of process and energetic facilities, such as hydrogen and hydrogen carriers storage and delivery systems. Recently proposed nonstandard ring-shaped specimen is used to test the fracture resistance of pressurised cylinders with defects (cracks or notches) in the most critical direction - axial. Some of the advantages of the pipe-ring notch bend specimen, PRNB, are simple fabrication and same material history as actual exploited structure. A combined experimental-numerical procedure is applied for prediction of fracture behaviour of specimens (applicable to ductile metals, mainly steels and Al alloys), with the aim to further validate the new specimen. The results obtained so far lead to conclusion that PRNB specimen can be applied in integrity assessment of cylindrical structures.
PB  - 14th International Conference on Fracture, ICF 2017
C3  - ICF 2017 - 14th International Conference on Fracture
T1  - Numerical analysis of fracture of non-standard ring specimen for examination of axially flawed cylindrical structures
EP  - 220
SP  - 219
VL  - 2
UR  - https://hdl.handle.net/21.15107/rcub_technorep_3483
ER  - 

@conference{
author = "Međo, Bojan and Rakin, Marko and Gubeljak, Nenad and Musraty, Walid and Matvienko, Y. and Milošević, M. and Sedmak, Aleksandar",
year = "2017",
abstract = "Integrity of cylindrical structures, such as pipes and small-scale pressure vessels, is typically assessed by testing fracture mechanics specimens, like compact tensile CT or single-edge notched bending, SENB. However, their fabrication is mainly not possible for thin-walled pressurised elements, commonly used in structures of process and energetic facilities, such as hydrogen and hydrogen carriers storage and delivery systems. Recently proposed nonstandard ring-shaped specimen is used to test the fracture resistance of pressurised cylinders with defects (cracks or notches) in the most critical direction - axial. Some of the advantages of the pipe-ring notch bend specimen, PRNB, are simple fabrication and same material history as actual exploited structure. A combined experimental-numerical procedure is applied for prediction of fracture behaviour of specimens (applicable to ductile metals, mainly steels and Al alloys), with the aim to further validate the new specimen. The results obtained so far lead to conclusion that PRNB specimen can be applied in integrity assessment of cylindrical structures.",
publisher = "14th International Conference on Fracture, ICF 2017",
journal = "ICF 2017 - 14th International Conference on Fracture",
title = "Numerical analysis of fracture of non-standard ring specimen for examination of axially flawed cylindrical structures",
pages = "220-219",
volume = "2",
url = "https://hdl.handle.net/21.15107/rcub_technorep_3483"
}

Međo, B., Rakin, M., Gubeljak, N., Musraty, W., Matvienko, Y., Milošević, M.,& Sedmak, A.. (2017). Numerical analysis of fracture of non-standard ring specimen for examination of axially flawed cylindrical structures. in ICF 2017 - 14th International Conference on Fracture
14th International Conference on Fracture, ICF 2017., 2, 219-220.
https://hdl.handle.net/21.15107/rcub_technorep_3483

Međo B, Rakin M, Gubeljak N, Musraty W, Matvienko Y, Milošević M, Sedmak A. Numerical analysis of fracture of non-standard ring specimen for examination of axially flawed cylindrical structures. in ICF 2017 - 14th International Conference on Fracture. 2017;2:219-220.
https://hdl.handle.net/21.15107/rcub_technorep_3483 .

Međo, Bojan, Rakin, Marko, Gubeljak, Nenad, Musraty, Walid, Matvienko, Y., Milošević, M., Sedmak, Aleksandar, "Numerical analysis of fracture of non-standard ring specimen for examination of axially flawed cylindrical structures" in ICF 2017 - 14th International Conference on Fracture, 2 (2017):219-220,
https://hdl.handle.net/21.15107/rcub_technorep_3483 .

TY  - JOUR
AU  - Međo, Bojan
AU  - Rakin, Marko
AU  - Gubeljak, Nenad
AU  - Matvienko, Y.
AU  - Arsić, Miodrag
AU  - Šarkočević, Živče
AU  - Sedmak, Aleksandar
PY  - 2015
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/3057
AB  - Working conditions of casing pipes in drilling rigs can significantly influence the initiation and development of damage in the material, and therefore also the safe service of the entire system. In this work, an integrity assessment of a pipe with initial defect (machined surface crack) is presented. The position of this defect is on the external surface; unlike transport pipes, where internal surface is often endangered due to the contact with the fluid, casing pipes are also often exposed to damages at the external surface. A pipe segment exposed to internal pressure is examined experimentally and numerically, using the finite element method. Experimental setup included tracking of crack mouth opening displacement (CMOD) values, as well as J integral. Criteria for pipe failure are determined on the finite element (FE) models of the pipe; fracture initiation and plastic collapse are considered as failure mechanisms. Several 3D models with different crack sizes are evaluated. 2D plane strain models are also examined, to determine the applicability limits of this simplified approach. Integrity assessment criteria for the analysed geometries are discussed. Assessment of fracture resistance of the pipeline material is also considered in this work. Besides the standard SENB specimens, Ring specimens cut from the pipe are tested, and the results are compared. Both specimen geometries are modelled using local approach to fracture, by application of the micromechanical Complete Gurson model (CGM), developed by Z.L. Zhang. It is shown that the Ring specimens have similar fracture conditions under bending load as SENB specimens. Since they are much simpler to fabricate from the pipe than standard specimens, it is concluded that they can be used for assessment of fracture of the pipes with axial cracks.
PB  - Pergamon-Elsevier Science Ltd, Oxford
T2  - Engineering Failure Analysis
T1  - Failure resistance of drilling rig casing pipes with an axial crack
EP  - 440
SP  - 429
VL  - 58
DO  - 10.1016/j.engfailanal.2015.05.015
ER  - 

@article{
author = "Međo, Bojan and Rakin, Marko and Gubeljak, Nenad and Matvienko, Y. and Arsić, Miodrag and Šarkočević, Živče and Sedmak, Aleksandar",
year = "2015",
abstract = "Working conditions of casing pipes in drilling rigs can significantly influence the initiation and development of damage in the material, and therefore also the safe service of the entire system. In this work, an integrity assessment of a pipe with initial defect (machined surface crack) is presented. The position of this defect is on the external surface; unlike transport pipes, where internal surface is often endangered due to the contact with the fluid, casing pipes are also often exposed to damages at the external surface. A pipe segment exposed to internal pressure is examined experimentally and numerically, using the finite element method. Experimental setup included tracking of crack mouth opening displacement (CMOD) values, as well as J integral. Criteria for pipe failure are determined on the finite element (FE) models of the pipe; fracture initiation and plastic collapse are considered as failure mechanisms. Several 3D models with different crack sizes are evaluated. 2D plane strain models are also examined, to determine the applicability limits of this simplified approach. Integrity assessment criteria for the analysed geometries are discussed. Assessment of fracture resistance of the pipeline material is also considered in this work. Besides the standard SENB specimens, Ring specimens cut from the pipe are tested, and the results are compared. Both specimen geometries are modelled using local approach to fracture, by application of the micromechanical Complete Gurson model (CGM), developed by Z.L. Zhang. It is shown that the Ring specimens have similar fracture conditions under bending load as SENB specimens. Since they are much simpler to fabricate from the pipe than standard specimens, it is concluded that they can be used for assessment of fracture of the pipes with axial cracks.",
publisher = "Pergamon-Elsevier Science Ltd, Oxford",
journal = "Engineering Failure Analysis",
title = "Failure resistance of drilling rig casing pipes with an axial crack",
pages = "440-429",
volume = "58",
doi = "10.1016/j.engfailanal.2015.05.015"
}

Međo, B., Rakin, M., Gubeljak, N., Matvienko, Y., Arsić, M., Šarkočević, Ž.,& Sedmak, A.. (2015). Failure resistance of drilling rig casing pipes with an axial crack. in Engineering Failure Analysis
Pergamon-Elsevier Science Ltd, Oxford., 58, 429-440.
https://doi.org/10.1016/j.engfailanal.2015.05.015

Međo B, Rakin M, Gubeljak N, Matvienko Y, Arsić M, Šarkočević Ž, Sedmak A. Failure resistance of drilling rig casing pipes with an axial crack. in Engineering Failure Analysis. 2015;58:429-440.
doi:10.1016/j.engfailanal.2015.05.015 .

Međo, Bojan, Rakin, Marko, Gubeljak, Nenad, Matvienko, Y., Arsić, Miodrag, Šarkočević, Živče, Sedmak, Aleksandar, "Failure resistance of drilling rig casing pipes with an axial crack" in Engineering Failure Analysis, 58 (2015):429-440,
https://doi.org/10.1016/j.engfailanal.2015.05.015 . .