Use and Validation of Electrical Measurements in MWD Drillings-PPT Presentation

PPT Presentation

Pdf Summary

The study evaluates whether electrical measurements from an electrified drilling rig can support measurement-while-drilling (MWD) interpretation. Developed by Fondasol, the rig uses electric motors instead of an internal-combustion engine and hydraulic systems, while providing performance comparable to a conventional 45-horsepower rig and reducing its carbon footprint.<br /><br />Researchers examined five investigations near Osthoffen, close to Strasbourg. The 6–9 m-deep boreholes were drilled with continuous flight augers through silty and gravelly sands, loess, and clay. Electrical motor data, including current and rotation measurements, were used to derive drilling parameters such as torque and specific drilling energy (SDE). Downthrust was corrected to account for the weight of the rotation head and drill string. Results were compared with drilling logs, local lithology, and pressuremeter tests.<br /><br />A more compact layer at approximately 2.5 m depth was associated with a slower advance rate and increased torque. In clay, torque and SDE stabilized, showing patterns consistent with pressuremeter results. Similar trends occurred across the investigations. However, elevated values in some upper layers were not reflected in the drilling logs and may have been influenced by friction between the augers and borehole walls.<br /><br />The findings indicate that torque and SDE derived from electrical consumption can correlate well with pressuremeter measurements in cohesive soils. The authors conclude that electrical MWD logs may be interpreted similarly to logs from conventional rigs, while emphasizing the need to investigate auger–borehole friction further.

Keywords

electrical measurements

measurement-while-drilling

MWD

drilling rig

torque

specific drilling energy

pressuremeter

borehole logs

cohesive soils

auger friction