PSI - Issue 17

Available online at www.sciencedirect.com Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2019) 000 – 000 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2019) 000 – 000

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Procedia Structural Integrity 17 (2019) 514–519

ICSI 2019 The 3 rd International Conference on Structural Integrity Degradation mechanisms in the operation of pressured pipelines Garan Martin a * , Šulko Miroslav a a Slovak University of Technology, Faculty of Mechanical Engineering, Institute of applied mechanics and mechatronics, Námestie slobody 17, 812 31 Bratislava, Slovak republic ICSI 2019 The 3 rd International Conference on Structural Integrity Degradation mechanisms in the operation of pressured pipelines Garan Martin a * , Šulko Miroslav a a Slovak University of Technology, Faculty of Mechanical Engineering, Institute of applied mechanics and mechatronics, Námestie slobody 17, 812 31 Bratislava, Slovak republic

Abstract Abstract

Many non-standard situations like subsoil slipping, vibrations, ... as well as degradation mechanisms of pipeline materials can occur in the operation of pressured pipelines. The article deals with the mechanisms of the degradation processes and their formation like corrosion, brittleness and steel ageing that may occur in operation of pipeline systems. Material ageing of steels is documented on specimens created from pipeline materials and obtained by experimental measurements on these specimens after the multi-annual operation. Many non-standard situations like subsoil slipping, vibrations, ... as well as degradation mechanisms of pipelin materials can occur in the operation of pressured pipelines. The article deals with th mechanisms of the degradation processes and their formation like corrosion, brittleness and ste l ageing that may occur in operation of pipelin syst s. Material ageing of steels is documented on specimens created from pipeline materials and obtained by experimental measurements on these specimens after the multi-annual operation.

© 2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ICSI 2019 organizers. © 201 9 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ICSI 2019 organizers. © 201 9 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ICSI 2019 organizers.

Keywords: pipeline; degradation; ageing Keywords: pipeline; degradation; ageing

1. Introduction 1. Introduction

The level of pipeline systems safety is generally determined as the multiple of the design loading needed to achieve the permanent deformations represented by the yield stress of material. In some cases, it is also given as a multiple of the projected loading which is required to achieve destruction so called destructive pressure. However, the design safety of pipeline systems can be changed. This change can be caused by a change in operating loading - e. g. due to the additional bending stress caused by the thermal expansion of the pipeline induced by temperature of the inner medium or by landslide or subsoil fall monitored by Chmelko (2015). Material properties of the pipeline The level of pipeline systems safety is generally determined as the multiple of the design loading needed to achieve the permanent deformations represented by the yield stress of material. In some cases, it is also given as a multiple of the projected loading which is required to achieve destruction so called destructive pressure. However, the design safety of pipeline systems can be changed. This change can be caused by a change in operating loading - e. g. due to the additional bending stress caused by the thermal expansion of the pipeline induced by temperature of the inner medium or by landslide or subsoil fall monitored by Chmelko (2015). Material properties of the pipeline

* Corresponding author. Tel.: +421-57296367. E-mail address: martin.garan@stuba.sk * Correspon ing author. Tel.: +421-57296367. E-mail address: martin.garan@stuba.sk

2452-3216 © 2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ICSI 2019 organizers. 2452-3216 © 2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ICSI 2019 organizers.

2452-3216  2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ICSI 2019 organizers. 10.1016/j.prostr.2019.08.068