Abstract
Realtime Wellbore cleaning and stability Monitoring Service has been deployed in the field, where several side-track wells had been drilled due to stuck pipe and consequent lost in hole equipment. Traditional drilling practices were to drill highly deviated wells with inconsistent ROP without having sufficient information about the borehole condition and with the narrow pore pressure margin, which regularly resulted in sustained losses, even leading to differential sticking. In addition to these challenges, the well geometry made it necessary to constantly maintain sufficient ECD sensitive to borehole condition.
The service consists of Advance cutting flowmeter measuring cumulative bulk solids recovery while drilling, along with sophisticated software application compensating for drilling fluid coating the cutting. The real-time delta between actual and expected cutting volumes in surface is therefore a direct indicator of borehole cleaning efficiency and thus compared with various drilling and hydraulics parameters to provide timely operational recommendation, optimizing drilling performance and pre-empt potential causes of NPT/ILT.
The service is successfully determining the maximum allowable ROP in relation to cutting recovery, optimizing the number of drilling fluid pills, and supporting torque and drag analysis including cutting effects to give early indication of potential stuck pipe. This has reduced the on-bottom circulation cycles, reaming time and tripping intervals; thus allowing to drill longer deviated or horizontal sections avoiding tripping to clean the borehole.
As a result, operator was able to drill the wells optimally; saving 3.5 days of rig time, and about 50% of the pill volume for each well. The total cost saving for 5 wells, with the service deployed mostly in 6" production section was USD – 1.075 Million. The solution has then deployed across multiple rigs, drilling similar challenging wells.
