PSI - Issue 36

ScienceDirect Available online at www.sciencedirect.com Sci nceD rect StructuralIntegrity Procedia 00 (2021) 000 – 000 Available online at www.sciencedirect.com ScienceDirect StructuralIntegrity Procedia 00 (2021) 000 – 000 Available online at www.sciencedirect.com

www.elsevier.com/locate/procedia www.elsevier.com/locate/procedia

Procedia Structural Integrity 36 (2022) 17–23

© 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the conference Guest Editors Abstract The results of practical inspections of the underground pipelines insulation damages distribution and the use of the method of non-contact current measurements are presented. Based on the mathematical model of magnetic field of the underground pipeline (taking into account the leakage of current into the environment), it is possible to distinguish local insulation damages, which is located at a distance greater than the depth of the pipeline. © 202 2 The Authors. Published by ELSEVIER B.V. Peer-review under responsibility of the 1st Virtual International Conference “In service Damage of Materials: Diagnostics and Pred iction” Keywords: Non-contact current measurements, underground pipeline, transient resistance, resistivity distribution, insulation damages. 1. Introduction Insulating coatings are the main passive protection of metal against corrosion in electrically conductive medium (Strizhevsky et al. (1981), DSTU 4219-2003, Norman, 2007, Nykyforchyn et al. (2009)). In sites of insulation damage, the aggressive environment interacts with metal structures resulting in corrosion damage. To protect the metal against corrosion in places of insulation damage, cathodic polarization with electric current from external source is used. The effectiveness of cathodic protection also depends on the condition of the insulation coating: the less damage of the insulation, the lower the current consumption and the larger the protection zone (Dzhala and Yuzevych (2019), Nyrkova et al. (2020)). 1st Virtual International Conference “In service Damage of Materials: Diagnostics and Prediction” Contactless testing of insulation damages distribution of the underground pipelines Roman Dzhala* , Bohdan Verbenets’, Vasyl’ Dzhala, Oleh Senyuk, Vitalii Lozovan Karpenko Physico-Mechanical Institute of the NAS of Ukraine, 5 Naukova St., Lviv 79060, Ukraine Abstract The results of practical inspections of the underground pipelines insulation damages distribution and the use of the method of non-contact current measurements are presented. Based on the mathematical model of magnetic field of t nderground pipeline (taking into account the leakage of current i to the environm nt), it is possible to distinguish loca insulatio amages, which is located at a distance gr at r than the depth of he pip line. © 202 2 The Authors. Published by ELSEVIER B.V. Peer-review under respons bility of the 1st Virtual International Conference “In service Damage of Materials: Diagnostics and Pred iction” Keywords: Non-contact current measurements, underground pipeline, transient resistance, resistivity distribution, insulation damages. 1. Introduction Insulating coatings are the main passive protection of metal against corrosion in electrically conductive medium (Strizhevsky et l. (1981), DSTU 4219-2003, Norman, 2007, Nykyforchyn et al. (2009)). In sites of insulation damag , the aggressive environment interacts with etal structures resulting in corrosion damage. T protect the met l against co ro on i places of sul tion damage, cathodic polarization with electric current from external source is used. The effectiveness of cathodic protection also depends on the cond ion of he insulation coating: the less damage of t insulatio , the lower the curr nt consumptio and the larger the protect on zone (Dzhala and Yuzevych (2019), Nyrkova et al. (2020)). 1st Virtual International Conference “In service Damage of Materials: Diagnostics and Prediction” Contactless testing of insulation damages distribution of the underground pipelines Roman Dzhala* , Bohdan Verbenets’, Vasyl’ Dzhala, Oleh Senyuk, Vitalii Lozovan Karpenko Physico-Mechanical Institute of the NAS of Ukraine, 5 Naukova St., Lviv 79060, Ukraine

* Corresponding author. Tel.: +38 066 8274923; fax: +38 032 264 9427. E-mail address: dzhala.rm@gmail.com * Corresponding author. Tel.: +38 066 8274923; fax: +38 032 264 9427. E-mail address: dzhala.rm@gmail.com

2452-3216 © 2022 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the conference Guest Editors 2452-3216 © 2022 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the conference Guest Editors

2452-3216 © 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the conference Guest Editors 10.1016/j.prostr.2021.12.077