Permanent repair to a live subsea pipeline
JAVA SEA, INDONESIA
The state-owned PGN (Perusahaan Gas Negara) supplies over 80 million customers with gas in Indonesia. One of their major offshore pipelines – transporting gas to Jakarta – showed signs of leakage during an inspection in 2013, and it was temporarily fixed with a clamp. A permanent repair was still required for this critical pipeline. In 2014, jointly with a renown Dutch professional diving firm, IRM Systems developed a suitable repair methodology and executed the permanent repair.
The repair had to be completed without shutting the pipeline down. The pipeline was at a depth of 30 metres, and required saturation diving services for a month. IRM Systems developed a methodology to stop the leakage of the temporary pipeline repair clamp in place. Based on extensive analysis on bending moments at the intersection, a permanent repair by means of a welded structural sleeve was performed, ensuring the long-term integrity of the remainder of the pipeline’s lifetime.
If you have a specific place to do a repair, like this one, you have to really calculate what kind of bending moments are exercised on the pipeline.
With our expertise in non-standard issues we were able to make sure that the repair mechanism was strong enough to withstand the stress caused at the intersection.