The diameter of the export pipeline was 24 inches, but reduced to 20 inches at the isolation location, providing a unique challenge for the project.
As a solution, STATS utilised the remotely operated Tecno Plug, deploying it on rigid stem bars as opposed to pigging it through the pipeline. It was able to be lowered with control and precision to the required section between the 20-inch valve and a bend in the pipe.
The remote Tecno Plug consisted of a communication module and an isolation module, attached to a door plug and the deployment frame.
STATS were able to provide demonstrations remotely for the work, which also allowed full client engagement during a period of travel restrictions due to the COVID-19 pandemic, which also reduced the otherwise-required travel expenses to verify the feasibility of the project.
Once the door plug was in position, the stem bar was deployed in sections through the door plug. The isolation plug was hydraulically set, activation the locks and dual seals.
Once the isolation of the section was completed, the gas in the section was vented and the replacement works were complete safely. Communication with the Tecno Plug was maintained throughout the process, ensuring the safety and success of the project.
After reinstatement pressure tests and leak tests, the remote Tecno Plug was unset and recovered from the pipeline.
STATS regional manager for Asia Pacific Gareth Campbell said that the project marked a significant milestone for the company.
“The Tecno Plug offers a high level of safety while providing a cost-effective solution for the operator, this successful isolation prevented the operator from depressurising and purging the entire gas pipeline,” said Campbell.
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