Overcoming Challenges In Performance Validation Of Fiber-Optic Pipeline Leak Detection Systems

External Leak Detection systems based on distributed fiber optic sensors (DFOS) o ffer the exciting potential to significantly reduce the overall amount of spilled product before a l eak is detected and localized. As an external system, the validation of system performance and equally the verification of an operational installed system is a known challenge since, unlike in a conventional system, leaks cannot easily be simulated. As an example, the detection of a negative pressure pulse – a key detection mode for a Rayleigh based system requires test facilities >500m extent with leaks created at operational pressure in a full-bore pipeline. As a result, industrial focus has traditionally been deployed on lower level research-oriented test data rather than full scale validation.
OptaSense® have worked with the industry test facility CTDUT in Brazil to establish a unique test bed where realistic pipeline leaks can be created in full flow conditions. The results from this have been used to val idate a realistic performance basis of small 15 lpm l eaks detected via their negative pressure pulse in ~10 seconds and larg er 150 lpm leaks detected by multiple modes in ~1 minute. Valid automated detection of NPP was observed down t o 1mm holes in the pipe – a leak rate of only 1.5 lp m. The use of the negative p ressure pulse is shown as a compelling detection method but needs care to deploy in testing since the use of a valve to create a pulse is shown to be inferior in comparison to burst disks due to the increased valve-opening time that gives rise to a reduced amplitude pressure pulse. This paper argues for the necessity of large-scale validation approaches to performance bound acoustic-based leak detection systems and presents established options for in-field verification on customer owned systems.
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Pipeline Technology Journal 1/2020
Issue 1/2020 of ptj is a special edition for the ptc - Pipeline Technology Conference
For the first time the ptj will feature all papers from the Pipeline Technology Conference. This issue is therefore bigger than usual.
On its 137 pages this issue will discuss several topics. From data analysis of pipeline coating degradation, the use of vibroacustic technology right up to a improved analysis for subsea installations. This issue contains 16 papers from different companies.