UCL Discovery
UCL home » Library Services » Electronic resources » UCL Discovery

Condition assessment of damaged elbow in subsea pipelines

Lee, GH; Seo, JK; Paik, JK; (2017) Condition assessment of damaged elbow in subsea pipelines. Ships and Offshore Structures , 12 (1) pp. 135-151. 10.1080/17445302.2015.1116245. Green open access

[thumbnail of Paik_Condition assessment of damaged elbow-Final.pdf]
Preview
Text
Paik_Condition assessment of damaged elbow-Final.pdf - Accepted version

Download (1MB) | Preview

Abstract

The evaluation of the performance of aged structures is essential in the oil and gas industry, where inaccurate predictions of structural performance may lead to significant hazardous consequences. Elbows are critical structures subject to continuous corrosion that can lead to a burst or collapse. It is important to be able to predict both burst strength in continually corroding structures and the behaviour of the structures after critical corrosion takes place. Structural failures due to a significant reduction in wall thickness make it very complicated for pipeline operators to maintain pipeline serviceability. This paper discusses the plastic limit pressure of elbows without defects and with several local thinned areas. Finite element analysis (FEA) and the Goodall formula were used to evaluate the new formula. The results of the FEA show that the limit load of elbows under internal pressure differs with position and depth of damage. An empirical formula for the limit load of elbows with local thinned areas is proposed. Eight sizes of elbow were considered in this study, with Rm/t of 5, 6, 7.5, 9, 12, 15, 20 and 25. This range covers most of the piping used in high-pressure environments, such as nuclear and subsea situations. The method of numerical analysis was validated by experiment and with FEA results from the literature. The results of the study can be applied to both the operation and assessment of pipelines. A formula to predict the maximum burst strength of damaged elbows is presented, which will enable more accurate estimates of the time until pipelines need to be replaced or repaired.

Type: Article
Title: Condition assessment of damaged elbow in subsea pipelines
Open access status: An open access version is available from UCL Discovery
DOI: 10.1080/17445302.2015.1116245
Publisher version: http://doi.org/10.1080/17445302.2015.1116245
Language: English
Additional information: This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions.
Keywords: elbow, corrosion, burst pressure, 22g steel, local thin area, condition assessment, pipeline serviceability, modified Goodall formula
UCL classification: UCL
UCL > Provost and Vice Provost Offices
UCL > Provost and Vice Provost Offices > UCL BEAMS
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science > Dept of Mechanical Engineering
URI: https://discovery.ucl.ac.uk/id/eprint/10052193
Downloads since deposit
90Downloads
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item