The results of three non-intrusive inspection (NII) trials – organised by the Oil & Gas Technology Centre and Total UK – have demonstrated that the technology can deliver significant North Sea cost, safety and efficiency benefits compared with traditional intrusive methods.
NII enables pressure vessels to be inspected with the equipment on-line and avoids the requirement for entry into confined spaces to perform the examination.
The capability of NII technology is increasing year on year and offers the following prospective benefits to the N. Sea industry:
- Safety – up to 80% fewer confined space entries with a corresponding reduction in the number of line breaks and subsequent leak tests
- Financial – increased production and lower maintenance costs worth circa £242 million pa to the sector
- Increased equipment availability reducing lost and deferred production
- Shorter Turnarounds – reductions in duration of 33% have been achieved
- Overall cost savings of up to 80% compared to inspections that involve entry into a vessel.
However, the current use of NII in the sector is limited with some operators currently making little or no use of NII. The potential is that up to 80% of vessels could be examined non-intrusively.
Total identified two process pressure vessels on its Elgin Franklin platform that it would intrusively inspect during a shutdown, with the results shared and compared with the industry.
Three contractors – Eddyfi Technologies, Mistras and Sonomatic – were selected to conduct the field trials, and they deployed a range of ultrasonic corrosion mapping and time of flight diffraction solutions.
The Oil & Gas Technology Centre is a not-for-profit, industry-led, technology research and development organisation based in Aberdeen.
The three NII trials took place while the vessels were online and operating, and the intrusive inspections were later completed as planned during the shutdown.
The NII scopes did not detect any significant defects that would pose a risk to the integrity of the pressure vessels, and the intrusive inspection confirmed the same. The results correlated meaning NII delivered the same outcomes but without the requirement for a costly shutdown and potentially hazardous man entry into the vessels.
The Technology Centre and Total were commended by industry for their collaboration and won the Maximising Economic Recovery (MER) UK 2017 Award for their work on the trials.
Rebecca Allison, OGTC Asset Integrity Solution Centre Manager, said: “Process vessel inspection is a major cause of production downtime and costs the industry hundreds of millions every year.
“The trials were successful and demonstrate that NII can help operators achieve significant efficiencies in maintenance and integrity costs, while improving production uptime.
“We recently completed a non-intrusive inspection survey with ABB which identified significant potential benefits for adopting NII in the North Sea. It’s encouraging to see that the trial outcomes support the study results and we’d like to hear from any operators who are interested in to conducting future NII trials on their assets.”
Dave MacKinnon, Head of Technological Innovation, Total E&P UK, added: “The future of the offshore industry depends on companies embracing new technology.
“The field trials of new non-intrusive inspection (NII) technology has the potential to reduce both the costs of inspection and the number of times we need to work in restricted spaces. “
5 Jan 2018