The next generation of risk-based inspection for coal seam gas wells
Scott Collins A and Joel Everson B CA Origin Energy, Level 28, 180 Ann Street, Brisbane, Qld 4000, Australia.
B Wood PLC, Level 20, 127 Creek Street, Brisbane, Qld 4000, Australia.
C Corresponding author. Email: Joel.Everson@woodplc.com
The APPEA Journal 60(2) 611-615 https://doi.org/10.1071/AJ19201
Accepted: 24 February 2020 Published: 15 May 2020
Abstract
The coal seam gas (CSG) industry presents some unique mechanical integrity and assurance challenges, in particular: (1) the large well count (thousands), many of which are not identical (in design, process, equipment and layout), and hence have varying inspection requirements; (2) the geographic spread of wells within a field; (3) relying heavily on inspection to confirm equipment condition; (4) significant water and sand production; and (5) rapidly changing process conditions over the life of the well. One particular challenge for many operators is the potential for loss of containment in well-site pressure equipment from very high erosion rates. This, combined with the large asset count, makes physical inspection of each component to ensure equipment condition a challenging and costly task. So, what can a business do to develop an adaptive maintenance strategy to address changing process conditions, allowing them to intervene proactively before a failure occurs and maximising the opportunity to lengthen inspection intervals and reducing inspection costs on low-risk assets? One CSG operator, in conjunction with a leading integrity management service provider, has developed and implemented a dynamic digital twin of the physical condition of their assets by combining live production, monitoring and inspection data, allowing the current and future condition of equipment to be modelled and a risk-based inspection (RBI) strategy that is evergreen and reacts to the changing process conditions. The system built on the NEXUS Integrity Centre platform uses several different predictive models to prioritise assets and components for inspection using live process data and a consistent RBI approach across all static pressure equipment, essentially providing a live digital representation of the current asset condition, the essence of a digital twin. The system provides a prioritised list of assets requiring inspection before the planned maintenance strategy while also highlighting opportunities to extend inspection intervals and thus take advantage of the potential reduction in on-going maintenance costs.
Keywords: adaptive maintenance strategies, asset integrity management system, asset management, degradation prediction, digital twin, inspection interval, inspection optimisation, maintenance strategy, mobility.
Scott Collins is the Chief Inspector at Origin Energy in Brisbane, Australia, and was the leader of the NEXUS IC RBI implementation for the Integrated Gas business. He has a Bachelor of Mechanical Engineering (Honours) from the University of Western Australia and a Master of Business Administration from La Trobe University, and has been with Origin for 5 years. Prior to this, Scott worked for Santos for over 15 years as the Process Safety and Technical Integrity Team Leader. His focus is on sustainable asset management solutions that deliver integrity excellence for the lowest life cycle cost. Scott is also a member of the American Petroleum Institute 581 RBI Committee. |
Joel Everson is a Lead Integrity Engineer at Wood in Brisbane, Australia, and has 10 years of experience working as a professional engineer since graduating with a Bachelor of Mechanical Engineering (Honours) from the Queensland University of Technology. Joel started his career at Queensland Alumina Limited in Gladstone, working in engineering teams focused on asset management, equipment inspections, fitness for service assessments and development of repair scopes. At Wood, Joel has been working on several operational readiness and operations support integrity projects for the CSG industry and various conventional gas assets, including the development of RBI plans for gas-processing facilities (onshore, offshore and upstream CSG), the development of integrity management plans for static pressure equipment, the establishment of erosion management strategies (including erosion modelling) and the development and implementation of asset integrity management systems (AIMS). Joel combines his hands-on operational experience with his developed knowledge of risk-based asset management to deliver cost-effective solutions to clients. |
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