PDTI's proprietary fixed-cutter bit and nozzle system capable of delivering 650 GPM of mud/shot slurry. courtesy Particle Drilling Technologies Ltd.

Houston-based oilfield services company Particle Drilling has succeeded in halving the time it once took to bore through the “hardest rock in North America” with its “hard-shot” Particle Impact Impact Drilling technology.

New surface equipment and a an eight-and-a-half-inch drill bit bored into the Travis Peak formation in East Texas at the rate of 17 feet per hour, compared to 4 ft/h with a conventional bit system.

The new trial tested a solids-processing and particle-storage unit and drilled at depths beyond 12,500 ft., from which 343 ft. of hard-rock were drilled and “on-bottom” drilling of 12 hours was achieved.

A new injection system for the abrasive “shot-like” particles makes drilling a closed-loop system allowing no escape or return of particles to the rig. Shot is entrained in drilling mud at two-percent by volume, striking rock 4.8 million times per minute, a statement said.

Oil companies are understood to have participated in the drillilng technology’s progresss with presentations of drilling scenarios.