Issued Patents All Time
Showing 26–42 of 42 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 7124842 | Cutting elements of gage row and first inner row of a drill bit | Alan W. Lockstedt, Gary R. Portwood | 2006-10-24 |
| 7100711 | Single cone rock bit having inserts adapted to maintain hole gage during drilling | George Witman, Peter Wilson, Michael A. Siracki | 2006-09-05 |
| 7086489 | Multi-lobed cutter element for drill bit | — | 2006-08-08 |
| 6988569 | Cutting element orientation or geometry for improved drill bits | Alan W. Lockstedt, Gary R. Portwood | 2006-01-24 |
| 6929079 | Drill bit cutter element having multiple cusps | Vincent Shotton, Zhou Yong | 2005-08-16 |
| 6883624 | Multi-lobed cutter element for drill bit | — | 2005-04-26 |
| 6848521 | Cutting elements of gage row and first inner row of a drill bit | Alan W. Lockstedt, Gary R. Portwood | 2005-02-01 |
| 6827161 | Roller cone drill bit having non-axisymmetric cutting elements oriented to optimize drilling performance | Amardeep Singh, Sujian Huang | 2004-12-07 |
| 6640913 | Drill bit with canted gage insert | Alan W. Lockstedt, Gary R. Portwood | 2003-11-04 |
| 6527068 | Roller cone drill bit having non-axisymmetric cutting elements oriented to optimize drilling performance | Amardeep Singh, Sujian Huang | 2003-03-04 |
| 6059054 | Non-symmetrical stress-resistant rotary drill bit cutter element | Gary R. Portwood, Gary E. Garcia, James C. Minikus, Per Ivar Nese, Chris E. Cawthorne | 2000-05-09 |
| 5915486 | Cutter element adapted to withstand tensile stress | Gary R. Portwood, Dennis Cisneros | 1999-06-29 |
| 5868213 | Steel tooth cutter element with gage facing knee | Dennis Cisneros, James C. Minikus, Chris E. Cawthorne | 1999-02-09 |
| 5839526 | Rolling cone steel tooth bit with enhancements in cutter shape and placement | Dennis Cisneros, James C. Minikus, Chris E. Cawthorne | 1998-11-24 |
| 5421424 | Bowed out chisel insert for rock bits | Gary R. Portwood, James C. Minikus, Michael A. Siracki | 1995-06-06 |
| 5351770 | Ultra hard insert cutters for heel row rotary cone rock bit applications | Chris E. Cawthorne, Gary R. Portwood, Michael A. Siracki | 1994-10-04 |
| 5152194 | Hardfaced mill tooth rotary cone rock bit | Madapusi K. Keshavan, Robert H. Slaughter, Jr. | 1992-10-06 |