Shell - Rocky Umbilical Post-Mortem
GATE undertook an investigation into recovered, decommissioned equipment to determine both the cause of failure and investigate integrity of components that may not have failed. This information has proven invaluable to operators who can base the performance of other equipment of a similar type and construction in a similar environment. This was significant as the recovered materials ranged from the mud-line, to sea surface and topsides.
The investigation included: A materials integrity assessment of all recovered components, a materials integrity assessment of the condition of the structural mid-line and end terminations, noting any influence of exposure in the vicinity of the exposure, comparison of the respective degree of degradation for those sections deployed in atmospheric conditions, seawater and seabed zones, and laboratory test to identify the compositions any peculiar materials present.
GATE was also a part of an effort to determine the performance of cathodic protection on subsea equipment. The investigation also looked at other forms of corrosion protection used on different parts of other decommissioned subsea equipment. This investigation was able to not only determine but also quantify the benefits offered by cathodic protection through a comparison of the areas that were protected by the cathode to those that were electrically isolated form the cathode and did not benefit form cathodic protection.
