When it comes to keeping pipelines in top operating condition, the operator of two gas field developments offshore Malaysia has its work cut out. To make certain that the networks continue to deliver natural gas to the millions of residents and businesses in Peninsular Malaysia, dedicated maintenance teams work around-the-clock to monitor the lines for potential integrity threats, executing rigorous maintenance programs.
When several leaking valves were detected across multiple major gas trunk lines, as well as a defective section of feed line piping, the operator moved to replace them safely and quickly. To ensure that gas would flow with minimal disruption while essential repairs were made, the operator retained global pipeline service provider T.D. Williamson (TDW).
The repair program required replacement of two shutdown valves on two gas export pipelines attached to the drilling/riser platform, located approximately 135km northeast of Kertih. In addition, replacement of launcher valves and a piping section of the 52-slot drilling/riser platform located offshore Terrangganu, Malaysia was also necessary. TDW used its remote-controlled SmartPlug® pipeline pressure isolation system to create a double-block isolation against gas pressure on the four individually designated repair zones for a period of two to three weeks each, so that each section could be depressurized. Previously, TDW had successfully isolated sections of the Terrangganu platform to facilitate a tie-in to a neighboring field, so they were experienced in working on the platform.
External pigging pumps were used to pig the SmartPlug tool into position. The SmartPlug tool is operated and monitored entirely by remote control using the SmartTrack™ system, which transmits commands and receives pipeline and operational data through the pipe wall. The system tracks the SmartPlug tool’s location and monitors pipeline pressure.
Each of the isolations was maintained for an average of seven days at a safe operating pressure of approximately 70 – 80 bar (1015 – 1160 psi). As a result, TDW helped the operator achieve a safe environment in which repair work was carried out as planned, with minimal downtime.
Reduced costs, time and downtime
The four isolations were carried out on schedule, allowing the piping and valves to be replaced, safely and efficiently. “The operator appreciates that leaking valves and defective pipeline pose a serious threat to safety and pipeline integrity,” said Rolf Gunnar Lie, Regional Business Development Manager – Far East Asia Pacific for TDW. “In view of this, it is extremely satisfying that this customer was able to benefit from TDW’s isolation technology, which made it possible for them to make repairs with minimal impact on production and the environment, while saving time and money.”
Press Release, July 28, 2014; Image: TDW