News and media releases

Vibration-induced fatigue assessment of piping

15/12/2007

Woodside Energy Ltd, one of Australia’s largest publicly traded exploration and production companies, asked Shell Global Solutions to help determine the dynamic behaviour of its heavy mixed refrigerant (HMR) inlet line, which was causing integrity concerns.

A best practice developed in co-operation with Shell E&P Europe was used to assess the piping. The best practice for the mitigation and analysis of vibration-induced fatigue in an asset throughout its life cycle covers the initial screening of piping systems. It also provides sophisticated tools and analysis methods for a more detailed assessment of specific pipelines.

The vibration in the HMR inlet line of the main cryonic heat exchanger in a liquefied natural gas (LNG) train at Woodside’s Karratha plant, Western Australia, was measured. The screening measurements showed that the pipeline was potentially at risk of unexpected failure, which could have caused a shutdown resulting in an impact on production. However, the pipeline was found to be fit for service after a more detailed analysis.

Gordon Mathwin, Chief of Mechanical Engineering at Woodside Energy Ltd, says, “Given our long established close working relationship with Shell Global Solutions, we were confident that our requirement for rapid turnaround of the analysis could be met despite the short notice. I was very pleased with the expediency and quality of the deliverables.”

Shell Global Solutions also used the best practice to assess the vibration in the main inlet line of a distillation column that had been causing similar concerns for the Compagnie Rhénane de Raffinage refinery at Reichstett, France. For this line, sufficient integrity was demonstrated using the best practice methodology. In addition, mitigating measures were proposed to help reduce the vibration levels, including additional or modified local pipe supports and changes in process flow throughput.