Enhance hole-cleaning effectiveness and monitor borehole stability through accurate measurement and analysis of cuttings recovered from the well.
Published: 05/03/2016
Published: 05/03/2016
When drilling in a remote onshore oil field in the Middle East, an operator wanted to drill a lateral section in one run with quality hole cleaning and minimized connection time. This required the operator to reduce flat time incurred through stuck-pipe incidents, circulating bottom-up timing, and wiper trips. The operator also sought to maximize ROP and footage, which are usually limited by wellbore cleaning challenges.
Schlumberger engineers recommended an integrated solution that included advanced cuttings surveillance, mud monitoring, and a robust rotary steerable system. The team suggested combining the PowerDrive Orbit RSS with the ShortPulse integrated MWD platform because the combination would provide the directional control necessary to drill the lateral section in one run. The fully rotating PowerDrive Orbit RSS reduces drag, improves ROP, decreases the risk of sticking, and achieves superior hole cleaning.
In addition, the CLEAR service was used to monitor hole cleaning effectiveness and wellbore stability. Using a cuttings flowmeter, the service continuously weighs, measures, and analyzes cuttings reaching the surface. By comparing measured and theoretical volumes, the CLEAR service provides early detection of inadequate hole cleaning and excess returns caused by wellbore instability (caving) or damage. An M-I SWACO mud specialist provided support to the mud engineer on the rig, ensuring that the mud system was in good condition during drilling.
Using the integrated solution, the operator was able to steer the well trajectory into the reservoir zone with low tortuosity and increased ROP. The section was drilled 2.5 days ahead of plan with minimal stick/slip, shock, and vibration. The operator achieved optimal hole cleaning with cumulative cutting recovery of 84.4% and with a 51% reduction of cumulative pill volume.
Additionally, a new field record for drilling a 61/8-in section with a stand-alone RSS was achieved—this operation’s average ROP was 91.3 ft/h, and previous jobs’ average was 72.3 ft/h. Footage increased to 1,978 ft/d compared with the previous record of 1,409 ft/d. The operator also reduced connection time by 60% toward the end of run and saved USD 148,000, or 32%, off AFE.
Challenge: Drill lateral section in one run with desired hole cleaning and minimized connection time.
Solution: Use CLEAR hole cleaning and wellbore risk reduction service along with the PowerDrive Orbit RSS and the expertise of a mud supervisor from M-I SWACO, a Schlumberger company.
Results: