Kuwait Oil Company (KOC) is responsible for exploration, production and exporting crude oil in the State of Kuwait. As part of the Company’s expansion to increase the production, several new pipelines have been constructed. At the export tank farm storage area, four new filling pipelines were commissioned in 2009 as these pipelines are strategically important for sustaining crude oil export.
In May, 2014, a leak was reported in a 34” (863 mm) diameter pipelines due to internal corrosion and subsequently three more leaks occurred. Moreover, another 34” (863 mm) diameter pipelines leak was reported during the same period. Since the pipelines leaked after a short span of 5 years in operation, it was considered a serious threat, both pipelines were inspected by using ultrasonic ILI tool where severe internal corrosion damage was detected. This necessitated further investigations to determine the root-cause of the internal corrosion, so that remedial measures can be taken. Internal Corrosion Direct Assessment (ICDA) methodology was utilized to determine the root-cause of the internal corrosion of the filling pipelines.
This paper describes all the activities that have been carried out determine the root cause.
The filling lines in this paper experienced abnormal, short service-life failures in the span of just a few years after commissioning. These pipelines are critical to the conveyance, storage and ultimate shipment of export quality crude oil to the global community. Although the subject pipelines were inspected with intelligent pigging tools wherein severe internal corrosion was reported, the underlying reason or reasons for these failures was not established. Therefore, KOC’s Inspection & Corrosion department with their advanced NACE training and certifications, recognized that Internal Corrosion Direct Assessment (ICDA) could be of substantial benefit to resolving this problem and answering the gaps left by the inspection technique of ILI. Hence, the use of NACE International Standard Practices of ICDA, to determine why these abnormal failures and extreme internal corrosion was detected for a pipeline where the product is typically considered benign for the threat of internal corrosion. Selection of ICDA as an integrity validation tool would become a viable and smart choice in exposing problems and being able to address them systematically with a mitigation plan moving forward that made sense to all KOC teams.