Smith Bits introduces ONYX 360 rolling PDC cutter for improved durability
HOUSTON — Smith Bits, a Schlumberger company, has released the ONYX 360 rolling polycrystalline diamond compact (PDC) cutter. An industry first, this unique technology enables a PDC cutter to rotate 360° while drilling, significantly improving drillbit durability in abrasive formations and extending drillbit life and footage drilled per run.
Strategically positioned in the highest wear areas of a drill bit’s cutting structure, the ONYX 360 rolling cutter uses its entire diamond edge to shear the formation as the bit rotates, thereby distributing wear over its full circumference. Comparatively, only a small fraction of the cutter edge is used in a conventional PDC bit. This rotation allows the cutter’s diamond edge to stay sharp longer, increasing penetration rates and extending drillbit life compared to premium fixed PDC cutter technology. The new PDC cutter’s 360° rotation also reduces frictional heat buildup, resulting in less wear and fewer bit replacement trips.
“Over the past 40 years, significant improvements in PDC materials and processes have advanced cutter performance to levels where these tools are drilling ever-harder formations. Now, for the first time, a dynamic design has been introduced for PDC cutters, allowing for a step change in durability,” said Guy Arrington, president, Bits & Advanced Technologies, Schlumberger. “Field tests in a horizontal, abrasive sandstone interval have shown that bits fitted with the new rolling cutters drill more footage and exhibit less wear than those equipped with premium fixed cutter technology.”
In laboratory tests, the ONYX 360 rolling cutter was evaluated against a premium fixed PDC cutter drilling a block of hard granite. After 90 passes on this test formation, the premium fixed cutter developed an extreme wear flat compared to the ONYX 360 rolling cutters, which showed virtually no sign of wear even after 540 passes indicating a significant improvement in cutter durability.
During field testing, more than 80 runs and 130,000 ft were drilled. In the U.S. Midcontinent Granite Wash, PDC drill bits were fitted with the ONYX 360 rolling cutters to increase the amount of footage drilled. In one field test, footage was extended by 57% in the abrasive sandstone formation while ROP increased 26%. The new rolling cutters also exhibited uniform wear with no cutter loss and 100% cutter rotation compared to premium PDC fixed cutters that showed greater wear with less footage drilled.