Introduction

The project is taken place at Pattani FSO on Erawan Field, Thailand. The main contractor of de-commissioning work is InterMoor Pte Ltd and OCS was awarded by InterMoor Pte Ltd to perform Soil Plug Removal by using a water jetting and air lifting tool and internal pile cutting with water abrasive system tool. The mooring piles are plugged by clay soil with shear strength at 100 kPa and need to be excavated by 5 meter below original seabed. The Soil Plug Removal Tool (SPRT) is operated with water jetting pressure at 600 Psi and air lift with air pressure at 330 Psi, also equipped with swabbing brush tool to ensure inside wall of pile are cleaned before putting Internal Pile Cutter Tool (IPCT) into mooring pile. The IPCT itself is working with high pressure water up-to 2400 Bar mixed with abrasive garnet materials which to be used to cut through the 48” pile with 0.75” WT. As a result, total 6 piles are successfully cut and recovered to the vessel as a job scopes completion.