Subcon has announced a new method to mitigate pipeline-walking.
Developed in cooperation with Shell Global Solutions (Shell), it is an engineered ‘pipe-clamping mattress’ (PCM).
The technique was first developed on Shell’s Malampaya Project; as an alternative to traditional rock dumping. According to Subcon, the results were so encouraging that a further 15 PCMs were deployed on the same field in Q1 2018.
“When rock-dumping or concrete matts are deployed for walking mitigation, the vast majority of load is wasted because it is passed straight onto the seabed,” explained Subcon CEO Matthew Allen .
Addressing pipeline-walking with PCM’s rather than rock-dumping also eliminates the need for fall-pipe vessel and competent rock, Subcon noted.
Future field developments may consider a ‘wait-and-see’ philosophy for pipeline walking, thereby eliminated suction pile fabrication and installation. As pipeline-walking is an uncommon and slow process, remediation can be achieved using post-installed PCM’s.
Shell has a US patent pending for the PCM and has now released the PCM option to the market via a global licensing agreement with Subcon. Shell presented a technical paper on the Malampaya PCM’s at the Houston OTC.