| 10871036 |
Hybrid drill bit and design method |
Anton F. Zahradnik, Rudolf Carl Pessier, Don Q. Nguyen, Matthew J. Meiners, Michael S. Damschen +3 more |
2020-12-22 |
| 10316589 |
Hybrid drill bit and design method |
Anton F. Zahradnik, Rudolf Carl Pessier, Don Q. Nguyen, Matthew J. Meiners, Michael S. Damschen +3 more |
2019-06-11 |
| 10190366 |
Hybrid drill bits having increased drilling efficiency |
Anton F. Zahradnik, Robert J. Buske, Rudolf Carl Pessier, Don Q. Nguyen, Michael S. Damschen +5 more |
2019-01-29 |
| 10072462 |
Hybrid drill bits |
Anton F. Zahradnik, Rudolf Carl Pessier, Mitchell A. Rothe, Don Q. Nguyen, Michael S. Damschen +5 more |
2018-09-11 |
| 9670736 |
Hybrid drill bit |
Anton F. Zahradnik, Ron D. McCormick, Rudolf Carl Pessier, Jack T. Oldham, Michael S. Damschen +3 more |
2017-06-06 |
| 9353575 |
Hybrid drill bits having increased drilling efficiency |
Anton F. Zahradnik, Robert J. Buske, Rudolf Carl Pessier, Don Q. Nguyen, Michael S. Damschen +5 more |
2016-05-31 |
| 8678111 |
Hybrid drill bit and design method |
Anton F. Zahradnik, Rudolf Carl Pessier, Don Q. Nguyen, Matthew J. Meiners, Michael S. Damschen +3 more |
2014-03-25 |
| 8459378 |
Hybrid drill bit |
Anton F. Zahradnik, Ron D. McCormick, Rudolf Carl Pessier, Jack T. Oldham, Michael S. Damschen +3 more |
2013-06-11 |
| 8356398 |
Modular hybrid drill bit |
Ron D. McCormick, Rolf Carl Pessier, Don Q. Nguyen, Tim Marvel, Matthew R. Isbell +3 more |
2013-01-22 |
| 7845435 |
Hybrid drill bit and method of drilling |
Anton F. Zahradnik, Rudolf Carl Pessier, Don Q. Nguyen, Michael S. Damschen, Tim Marvel +1 more |
2010-12-07 |
| 7841426 |
Hybrid drill bit with fixed cutters as the sole cutting elements in the axial center of the drill bit |
Anton F. Zahradnik, Rolf Carl Pessier, Don Q. Nguyen, Michael S. Damschen, Tim Marvel +1 more |
2010-11-30 |
| 7621345 |
High density row on roller cone bit |
Robert J. Buske, James L. Overstreet, Rolf Carl Pessier |
2009-11-24 |