Publications

In 2019, Premier Oil Indonesia commenced drilling campaign to complete 4 development wells consist of 3 subsea development wells and 1 platform well at Natuna Sea Block with water depth 260ft - 280ft. To optimize the mobilization and demobilization cost, one single Jack Up rig was selected to complete those 4 wells. The Jack Up rig require several modifications to enable drilling and completing subsea wells. The Jack Up rig is equipped only with surface BOP stack; therefore, 16” HP riser is utilized to drill reservoir section then a Suspended Texas Deck (STD) was required as means to suspend the weight in order to hang 16” HP riser stack and also it is designed to take the full BOP weight in the event the secondary BOP tensioner fail. A modification work was also performed on Conductor Tensioner Platform (CTP) to extend it to accommodate Subsea Tree temporary storing of Subsea Tree complete with Tree Running Tool (TRT) for inspection and preparation prior to subsea deployment. On the other hand, Subsea Tree has Protection Structure Assembly (PSA) has the biggest dimension among other subsea equipment which leaving only option to be deployed by TDS directly from supply vessel to the wellhead using ROV-friendly lifting bridle arrangement. The drilling campaign has successfully completed and met drilling objectives without major safety case. It is proven that with collaborative engineering works involving company, rig contractor and third party contractors enabling the success of subsea drilling and completion campaign in shallow water at Natuna Sea Block using Jack-up rig. The lesson learned was established upon completing drilling the 1st well then applied to next well resulting significant time improvement to complete the well from 52 days to become only 35 days, noting that these 2 wells have similar drilling and completion profile.