Challenge: Maintain verticality in 17½-in hole section to avoid nearby well and minimize vibration while drilling exploration well through many coal layers offshore Malaysia.
Solution: Drill with BHA incorporating PowerV vertical drilling system, a 171⁄2-in PDC bit, and roller reamer. Provide OSC interactive drilling operations support for vibration monitoring.
Result: Drilled 1,716.6 m in single run, setting a new record. Minimized vibration, avoided losses while drilling, and maintained verticality.
Petronas was drilling an exploration well—SBD-2—in the SB field offshore Malaysia. The primary objective was to test the hydrocarbon potential of three groups—Lower E, F, and H.
Because SBD-1, a sister well, had been drilled only about 50 m away, maintaining verticality while drilling the 17 1/2-in hole section of SBD-2 was essential. Keeping vibration as low as possible was also necessary to minimize the risk of losses while drilling through many layers of coal.
Petronas selected the PowerV vertical drilling system for the 17 1/2-in section. The 17 1/2-in PDC bit from Smith Bits, a Schlumberger company, was, designed specifically for this application and this well based on IDEAS integrated drillbit design platform modeling and vibration analysis.
To minimize vibration, the PowerV BHA incorporated a roller reamer to reduce the stick/slip experienced in offset wells. Vibration monitoring support provided by OSC experts helped avoid losses during the run.
The PowerV system drilled the 17 1/2-in hole section of SBD-2 from a depth of 307 m to a depth of 2,023.6 m in a single 1,716.6-m run. Weight on bit ranged from 15,000 to 25,000 lbf and rotation speed from 80 to 110 rpm. Average ROP was 23 m/h, and verticality was maintained throughout the run—maximum inclination was 0.1°, and vertical displacement was just 0.6 m.
Downhole vibration was kept to a minimum, and there were no losses while drilling. This contributed to borehole quality that enabled smooth running of the 13 3⁄8-in casing and helped set a new record for 17 1/2-in hole drilled in a single run with a PowerV vertical drilling system.
Download: PowerV System Sets Record for Longest Run in Petronas Exploration Well Offshore Malaysia (1.01 MB PDF)