Leak located on 22km North Sea umbilical
Telepath® facilitates for remediation work plan
- Client Major Operator
- Leak Location 22 km
- Location North Sea
- Nominal Bore 1 inch Methanol
Challenge
A leak was identified in the methanol core of a client’s umbilical when attempts to restart the drill centre failed through loss of pressure. Topsides pump testing confirmed that the failure had occurred subsea.
The umbilical had a total length of 22km with three drill centres tied in at various points along its length. Investigations identified a leak in a one-inch methanol core within the umbilical. As a result of the leak, the methanol pump on the platform could only achieve a maximum of 50 bar pressure in the line, at a low rate of approximately 1 m3/hr.
Solution
A Brinker team was mobilised offshore with all necessary pumping and metering equipment and the required data was obtained. This data was then analysed using Telepath®, which enabled the leak location to be identified.
Outcome
The Telepath® results indicated that the leak was located 12.3km +/-0.6km from the platform and that the leak size increased almost fourfold when the pressure increased from 5 to 24 bar (72 to 350psi). This suggested that, as opposed to a point defect, the leak was likely to be a circumferential or axial crack, which opened up with increased pressure.
The upside
Completion of this work has enabled the operator to plan the most appropriate remediation having gained significant understanding of the problem.
Example of the outputs of the Telepath® model
