Dry and Lubricated Bit Cutter-on-Rock Tribometry (BCORT)

In the harvesting of fossil fuels and other natural resources, drilling is estimated to be an average of 50% of total project costs. Despite this high expenditure, simple drilling simulations in the laboratory setting are very difficult to find. This work focuses on rock cutting experiments in order to study rate-of-penetration, as well as cutter temperature, friction, and wear as functions of relevant drilling materials and interfaces. These include tool steel, carbide, and PDC cutters on sandstone, limestone, marble, and shale in lubricated and un-lubricated conditions.
Debris Generation in Dry Rock Cutting
PFTL Research Assistant(s):   Patrick S. M. Dougherty; Randyka Pudjoprawoto; Jeremiah N. Mpagazehe; John T. Shelton
Method(s) Employed:   High/low speed and load tribometry; in situ data acquisition, High Speed Video; ex situ optical interferometry, rock substrate/cutter preparation
Rig(s) and/or Software(s) Employed:   In-house Bit Cutter-on-Rock Tribometer for dry drilling conditions; Modified Bruker UMT-3 for lubricated drilling conditions; Zygo New-View 7300 Optical Interferometer
Sponsor(s):   NSF GRFP Fellowship; DOE EERE Fellowship

Sample Results:


Rock Samples: Mancos Shale, Carthage Marble, Nugget Sandstone

PDC Cutter

rock samples pdc cutter



Select PFTL References:

1.Dougherty, P., Pudjoprawoto R., Higgs III, C.F. "Bit Cutter-on-Rock Tribometry: Analyzing Friction and Rate-of-Penetration for Deep Well Drilling Substrates." Submitted for Review: Tribology International, November, 2013

2. Dougherty, P., Mpagazehe, J., Shelton, J., Higgs III, C.F. "Multi-phase Bit-Cutter-on-Rock Tribometry: Understanding the Drilling Process for Renewable Energy Resources," Proceedings of: World Tribology Congress. Torino, Italy, September 2013