Issued Patents All Time
Showing 1–12 of 12 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 7152701 | Cutting element structure for roller cone bit | Richard Butland, John James Herman, Ronald Birne-Browne, Louis Loiselle, J. Daniel Belnap | 2006-12-26 |
| 6510909 | Rolling cone bit with gage and off-gage cutter elements positioned to separate sidewall and bottom hole cutting duty | Gary R. Portwood, Gary E. Garcia, James C. Minikus, Dennis Cisneros, Chris E. Cawthorne | 2003-01-28 |
| 6484826 | Engineered enhanced inserts for rock drilling bits | Nathan R. Anderson, J. Daniel Belnap, Chris E. Cawthorne, Ronald K. Eyre, Madapusi K. Keshavan +2 more | 2002-11-26 |
| 6460637 | Engineered enhanced inserts for rock drilling bits | Michael A. Siracki, Chris E. Cawthorne, Madapusi K. Keshavan, J. Daniel Belnap, Ronald K. Eyre +1 more | 2002-10-08 |
| 6460636 | Drill bit inserts with variations in thickness of diamond coating | Zhou Yong, Suprant J. Huang, Nathan R. Anderson, J. Daniel Belnap, Chris E. Cawthorne +4 more | 2002-10-08 |
| 6419034 | Engineered enhanced inserts for rock drilling bits | J. Daniel Belnap, Ronald K. Eyre, Michael A. Siracki, Madapusi K. Keshavan, Nathan R. Anderson | 2002-07-16 |
| 6390210 | Rolling cone bit with gage and off-gage cutter elements positioned to separate sidewall and bottom hole cutting duty | Gary R. Portwood, Gary E. Garcia, James C. Minikus, Dennis Cisneros, Chris E. Cawthorne | 2002-05-21 |
| 6199645 | Engineered enhanced inserts for rock drilling bits | Nathan R. Anderson, J. Daniel Belnap, Chris E. Cawthorne, Ronald K. Eyre, Madapusi K. Keshavan +2 more | 2001-03-13 |
| 6059054 | Non-symmetrical stress-resistant rotary drill bit cutter element | Gary R. Portwood, Gary E. Garcia, James C. Minikus, Chris E. Cawthorne, Scott D. McDonough | 2000-05-09 |
| 5967245 | Rolling cone bit having gage and nestled gage cutter elements having enhancements in materials and geometry to optimize borehole corner cutting duty | Gary E. Garcia, Gary R. Portwood, James C. Minikus, Dennis Cisneros, Chris E. Cawthorne +1 more | 1999-10-19 |
| 5853055 | Rock bit with an extended center jet | Michael A. Siracki, Alan W. Lockstedt, Dennis Cisneros, Michael S. Oliver, Gary R. Portwood | 1998-12-29 |
| 5833020 | Rolling cone bit with enhancements in cutter element placement and materials to optimize borehole corner cutting duty | Gary R. Portwood, Gary E. Garcia, James C. Minikus, Dennis Cisneros, Chris E. Cawthorne | 1998-11-10 |