TDW Finishes Isolation Ops Offshore Malaysia
TDW Offshore Services (TDW) has successfully completed a series of pipeline pressure isolation operations offshore western Borneo in Malaysia for Sarawak Shell Berhad. The operations were carried out on the Jintan, B11 and F6 platforms in the South China Sea, as part of Sarawak Shell Berhad's ongoing pipeline valves maintenance program.
Pipeline pressure safely isolated
The first of the three operations took place on the Jintan platform on a 24-inch gas export pipeline that extends from the JNDR-A platform to platform M1 off the West coast of Sarawak. TDW executed a double-block pressure isolation against 90 bar pipeline pressure so that Shell could safely replace a passing shut down valve (SDV). A 24-inch SmartPlug® isolation tool was pigged using production gas approximately 30 meters into the pipeline and set at the vertical section of the riser. Throughout the entire operation the SmartPlug tool was remotely operated, monitored and tracked continuously by TDW with its SmartTrack™ technology. The SmartTrack system, which uses proprietary electromagnetic and Extremely Low Frequency (ELF) technology, provides the operational security required to safely isolate pipelines in a wide range of operating environments. After the topside section was safely depressurized, a spool section was replaced and a new flange welded to it to accommodate the new shutdown valve. TDW utilized a joint tester tool to verify the flange installation prior to Shell installing the replacement SDV. Overall, the affected section was isolated for a period of 13 days at a pressure of 90 bar while necessary testing and SDV installation took place.
Passing motor-operated valves (MOVs) replaced at B11-A platform
On the second operation, a 32-inch SmartPlug isolation tool was utilized to replace two passing launcher motor-operated valves (MOVs) on a 32-inch gas export pipeline at the B11 platform that connects to the E11RB platform. By pigging in a SmartPlug tool with water over a distance of 50 meters and monitoring it with SmartTrack technology, TDW set the tool vertically in the riser and created a double-block isolation against the gas pressure. The SmartPlug tool remained in the riser for eight days at 102 bar to facilitate safe replacement of the MOVs.
One-month isolation facilitates replacement of MOVs and topside maintenance
The third operation also involved replacement of launcher MOVs on a 32-inch gas export pipeline that extends from the F6P-A platform to the E11 hub. This particular operation required TDW to utilize the SmartPlug system to successfully isolate the pipeline against 70 bar. The pipeline was isolated for 11 days for the replacement of defective MOVs and an extended duration for additional topside maintenance activities.
TDW carried out all three pressure isolation operations with SmartPlug tools that were custom-built at its headquarters in Stavanger, Norway. Local support was provided by TDW personnel based in Singapore and TDW's agent Amserve Engineering in Malaysia.
Reliable isolation services play pivotal role in pipeline maintenance
Since 2001, TDW has performed a number of pipeline pressure isolation operations to facilitate safe valve replacements on behalf of Sarawak Shell Berhad in Malaysia. "On behalf of Shell and the SKME2 team, I would like to thank TDW for their commitment and dedication to making sure that the isolation operations were executed with care and attention to detail," said Redzuan Zulkflie, Mechanical Static Engineer for Sarawak Shell Berhad.
"I am very proud of the isolation work that the TDW team carried out for Shell in Malaysia," said Rolf Gunnar Lie, Business Development Manager for TDW. "As a result of our joint efforts, TDW successfully isolated the designated sections of the pipeline network for safe execution of riser valve replacement. Had Shell been required to depressurize the long pipelines to replace the valves, it would have caused longer production downtime. It would also have been extremely costly, time-consuming and harmful to the environment had flaring taken place," he added.