Casino pipeline: novel pipeline integrity inspection
Steve Henzell A C and Fiona Read BA Advisian Ltd, Level 13, 333 Collins Street, Melbourne, Vic. 3000, Australia.
B Santos Ltd, 60 Flinders Street, Adelaide, SA 5000, Australia.
C Corresponding author. Email: steve.henzell@advisian.com
The APPEA Journal 57(2) 603-606 https://doi.org/10.1071/AJ16049
Accepted: 9 March 2017 Published: 29 May 2017
Abstract
The Casino offshore pipeline required inspection to demonstrate the integrity of the pipeline and allow the operating life of the pipeline to be extended. There were numerous challenges in performing a conventional internal pipeline inspection which would have required diver operations to install and operate subsea pig launchers. Two alternative inspection methods were used to inspect the high priority sections of the pipeline, at the pipeline tees and in the horizontal directionally drilled (HDD) section of pipeline at the coastline crossing.The pipeline tees and well flowlines were inspected using an external magnetic flux inspection tool deployed by remotely operated vehicle (ROV), to test for top-of-line corrosion.
Bi-directional pigging from the onshore valve station, offshore for 30 km using gas from the host gas plant and then return to the shore using gas from the offshore wells allowed for inspection of the HDD pipeline with a total of 10 bi-direction pig runs completed. The pig position was accurately predicted by monitoring the operating conditions of the pipeline and confirmed by displacement past the subsea well closest to shore (Casino 5).
The novel pigging methods brought significant benefits for cost, schedule and reduced EHS exposure by avoiding diver operations. The cost of the overall inspection program was less than 25% of the conventional inspection methods and was achieved a year earlier than if a dive support vessel (DSV) had been mobilised.
The bi-directional pigging campaign proved to be highly successful.
Keywords: bi-directional pigging, pipeline inspection, pipeline integrity management.
Stephen (Steve) Henzell is an experienced facilities engineer with Advisian in Melbourne. He has over 30 years’ experience in oil and gas design and operation. Steve specialises in concept engineering and brownfield engineering, and provides global leadership in these areas within Advisian globally. He is also Advisian’s global leader for offshore facilities and specialises in minimum facilities platform designs. Steve has been involved with the Casino gas field in western Victoria from concept design, through the original development and subsequent field expansion, and with ongoing inspection and maintenance programs. |
Fiona Read is a production engineer with 5 years’ experience in the oil and gas industry. She has experience supporting both onshore conventional oil and gas assets in the Cooper Basin and offshore gas assets in the Otway Basin, Victoria. Fiona has been involved with the Casino gas field in western Victoria since 2015, supporting all aspects of operations including management of the offshore well strategies, optimisation of MEG chemistry and support to inspection and maintenance programs. |
