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Comprehensive Site Integrity Assessments and Mitigations for Unbonded Flexible Pipes

Unbonded flexible pipes have become a new trend in the oil and gas sector for transporting hydro-carbon products due to good service, reliability, and ease of installation, which can be translated to cheaper cost during design, manufacturing, instal-lation, and operations. However, due to limited inspection options during operation, unbonded flexible pipes are exposed to a greater risk of failure compared with conventional steel pipes. This paper investigates a new inspection approach to perform complete site integrity assessments of unbonded flexible pipes, which can be divided into three sub-activities: ultrasonic testing (UT), visual testing (VT), and cathodic protection survey. These activities will be conducted consecutively prior to performing any repairs. This paper also discusses mitigations and repair measures when there is damage to the unbonded flexible pipe.


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