Abstract
Delta Mahakam, located in East Kalimantan has been known as one of the old oil and gas fields in Indonesia which has been developed since 1970. With massive production over more than 50 years, the field has entered the brownfield period. The reservoir pockets get more difficult and challenging to reach. The environment is factory-drilling with a fast operation (up to 200 m/h instantaneous on-bottom penetration rate, multiple offline activities, and fast connections practices) and is considered to be reaching the saturation level. The challenge now is to identify the opportunity for marginal but continuous performance improvement to lower the overall drilling operation cost.
Specific to this Delta Mahakam brownfield, there are at least six (6) DD/MWD/LWD-related initiatives that were implemented to optimize the drilling operation: (1) Adaptive and Continuous development of drill bit design; (2) Robust metal-to-metal-based push-the-bit Rotary Steerable System (RSS) utilization to boost up ROP; (3) Downhole steerable motor with high torque performance power section to gain higher horsepower during drilling; (4) High-performance motorized RSS to improve performance in S-type high torque, interbedded high impact formation, and long reach wells; (5) Utilization of LWD tool with single co-located formation evaluation sensors to enhance safety, surface handling efficiency, and geo-stopping; (6) high-resolution real-time data for high-speed drilling and safe BHA pull out of hole (POOH).
For the last 5 years, despite the more challenging oil/gas reservoir pockets to be targeted, the directional and logging while drilling performance in Delta Mahakam continuously increased. The drilling statistics show that 19.5% higher on-bottom ROP has been achieved by transitioning the BHA drive system from an elastomer-based to a metal-to-metal-based push-the-bit RSS system. For wells with a steerable motor application (high DLS requirement in wash-out prone zone), the high-torque performance motor helped boost up sliding ROP, improving the total drilling on-bottom ROP by 24%. For the wells with special challenges (S-type high torque, interbedded high impact formation, long reach), the high-performance motorized RSS has proven to achieve 39% higher on-bottom ROP, which potentially saved 175 hours of drilling time from 7 wells drilled compared to the traditional RSS-standalone approach. On the invisible lost time (ILT) reduction side, the utilization of an integrated single-collar LWD tool saved the surface handling time by an average of 34%, and TD determination by 43%. All those performance improvements are achieved without sacrificing the real-time data quality supported by the high-frequency mud telemetry technology which transmits the signal 200% faster than the average technology available in the industry.
