Petroleum Development Oman (PDO) used a STATS Group 20 inch (508 mm) tethered Tecno Plug™ to isolate a branch on its live 1,760 km main oil pipeline, which runs from Nehada to Mina Al Fahal in Oman.
PDO approached STATS Group to engineer a solution for the safe removal of to remove 14 bends from bypass pipework around block valves, requiring that they isolate the branch below the bend .
A routine inspection revealed internal corrosion issues, including corrosion on the valve flange faces and pitting corrosion on the 90° bends.
PDO developed a strategy to carry out the maintenance that limited the disruption to production.
Five upgrades were completed during a scheduled shutdown and the other seven sites required bypass pipework isolation at an operating pressure of 55 bar (797 psi) for the upgrades to take place.
As full bore access to the bypass pipework was available, STATS proposed the use of a tethered Tecno Plug deployed from a temporary launcher by a flexible stem bar, and designed and manufactured a Tecno Plug capable of negotiating tight radius bends
The Tecno Plug was deployed around the corroded section and positioned in the short pipe section without interrupting the main line flow.
STATS also engineered a hydraulic deployment system to deliver the plug to the exact isolation location, meeting critical space requirements.
After maintenance works took place, a service test was performed to prove the integrity of the new flanged joints before the plug was unset and recovered.
In total, 14 bends across 7 sites throughout Oman were removed during the project.
For more information visit the STATS website.
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