Drill through interbedded formations with a high UCS

An operator planned to drill 3,117 ft [950 m] of a high-impact section in a well in the Volgograd region of Russia. The target interval consisted of hard limestone interbedded with anhydrite, dolomite, and claystone.The UCS of this section ranged from 10,000 to 45,000 psi [69 to 310 MPa]. The operator's main goal was to achieve maximum footage and ROP in these hard formations.

Place Stinger elements in AxeBlade bit to improve ROP

Schlumberger collaborated with the operator and, using the IDEAS integrated dynamic design and analysis platform, determined that an AxeBlade bit with strategically placed Stinger conical diamond elements would drill more aggressively and with better impact and wear resistance compared with standard PDC cutters. Projections from the IDEAS platform showed that the combination of shearing and cutting actions delivered by this customized AxeBlade bit would facilitate higher ROP; enable a more stable drilling experience; and minimize shock, vibration, and cutter wear to maximize drilling efficiency.

Overcome previous field-best ROP with minimal bit damage

The operator achieved an average ROP of 36.7 ft/h [11.2 m/h] per section—46% higher than the previous field-best ROP—with minimal bit wear and record footage drilled per bit. The bit drilled 1,623 m [5,325 ft], which is 56% longer than the previous best field result. In addition to these records, the AxeBlade bit enabled a 3-day reduction in drilling time compared with the rest of the field and saved USD 75,000 while drilling the section.