HOUSTON – TDW Offshore Services (TDW) has successfully completed a subsea pipeline pressure isolation operation in the Gulf of Mexico.
Carried out at a depth of 370 ft (113 m) against 870 psig, this isolation enabled the safe and effective tie-in of a piggable wye to the Mississippi Canyon Gas Pipeline, a 30-in. natural gas line running between the West Delta 143 platform and the Venice gas plant in Louisiana.
The isolation project utilized two remote-controlled 30-in. SmartPlug dual module pressure isolation tools to isolate 45 mi (72 km) of pipeline. Each tool was composed of two plug modules and two pigging modules. One of the tools provided double block isolation on the high-pressure side of the tie-in location.
The first module on the second tool provided a hydraulic locked barrier of the high-pressure side for the divers installing the wye. The second module on the second tool was used to perform a leak test to verify integrity of the new wye after installation.
Aboard the DSV Norman Commander, TDW technicians used the remotely-operated SmartTrack tracking and pressure monitoring system. Once the tools were set, the isolation period was about two and a half weeks.