| 8397841 |
Drill bit with cutting elements having functionally engineered wear surface |
Anthony Griffo, Ahigang Fang |
2013-03-19 |
|
| 7997358 |
Bonding of cutters in diamond drill bits |
Saul N. Izaguirre, Thomas W. Oldham, Kumar T. Kembaiyan, Gary Chunn, Anthony Griffo +1 more |
2011-08-16 |
|
| 7625521 |
Bonding of cutters in drill bits |
Saul N. Izaguirre, Thomas W. Oldham, Kumar T. Kembaiyan, Gary Chunn, Anthony Griffo +1 more |
2009-12-01 |
$40,040,000 |
| 7267183 |
Drill bit lubricant with enhanced load carrying/anti wear properties |
Alan W. Lockstedt, Alysia C. White |
2007-09-11 |
$28,330,000 |
| 7235211 |
Rotary cone bit with functionally-engineered composite inserts |
Anthony Griffo, Zhigang Fang |
2007-06-26 |
$26,352,000 |
| 7229077 |
Ordered elastomeric composite material |
Madapusi K. Keshavan, Anthony Griffo, Alysia C. White, Patricia Heel, Leroy N. Tinkham +1 more |
2007-06-12 |
$86,540,000 |
| 7121365 |
Rock bit with grease composition utilizing polarized graphite |
Alan W. Lockstedt |
2006-10-17 |
$66,041,000 |
| 6695079 |
Dual-seal drill bit pressure communication system |
Gary R. Portwood, Chris E. Cawthorne, Robert H. Slaughter, Jr., Roger Didericksen, Peter Thomas Cariveau |
2004-02-24 |
$19,922,000 |
| 6679342 |
Dual-seal drill bit pressure communication system |
Gary R. Portwood, Chris E. Cawthorne, Robert H. Slaughter, Jr., Roger Didericksen, Peter Thomas Cariveau |
2004-01-20 |
$35,567,000 |
| 6571889 |
Rotary cone bit with functionally-engineered composite inserts |
Anthony Griffo, Zhigang Fang |
2003-06-03 |
$16,991,000 |
| 6431293 |
Dual-seal drill bit pressure communication system |
Gary R. Portwood, Chris E. Cawthorne, Robert H. Slaughter, Jr., Roger Didericksen, Peter Thomas Cariveau |
2002-08-13 |
$20,152,000 |
| 6406030 |
O-ring seal with lubricant additives for rock bit bearings |
Zhigang Fang, Steven W. Peterson |
2002-06-18 |
$22,045,000 |
| 6196339 |
Dual-seal drill bit pressure communication system |
Gary R. Portwood, Chris E. Cawthorne, Robert H. Slaughter, Jr., Roger Didericksen, Peter Thomas Cariveau |
2001-03-06 |
$18,780,000 |
| 6123337 |
Composite earth boring bit seal |
Zhigang Fang, Sujian Huang, Chris E. Cawthorne, Brian A. James, G. Steve Kyker +1 more |
2000-09-26 |
$29,335,000 |
| 5842700 |
Composite rock bit seal |
Zhigang Fang, Sujian Huang, Chris E. Cawthorne, Brian A. James, G. Steven Kyker |
1998-12-01 |
$9,351,000 |
| 5668092 |
Rock bit grease composition |
— |
1997-09-16 |
$12,271,000 |
| 5589443 |
Rock bit grease composition |
Zhigang Fang |
1996-12-31 |
$16,636,000 |
| 5456327 |
O-ring seal for rock bit bearings |
Madapusi K. Keshavan, Steven W. Peterson |
1995-10-10 |
$4,706,000 |
| 5323863 |
O-ring seal for rock bit bearings |
— |
1994-06-28 |
$5,618,000 |
| 5152353 |
High speed rock bit |
Ernst Gugger |
1992-10-06 |
$1,989,000 |