| 11732531 |
Modular earth boring tools having fixed blades and removable blade assemblies and related methods |
Anton F. Zahradnik, Rudolf Carl Pessier |
2023-08-22 |
| 10871036 |
Hybrid drill bit and design method |
Anton F. Zahradnik, Rudolf Carl Pessier, Matthew J. Meiners, Karlos B. Cepeda, Michael S. Damschen +3 more |
2020-12-22 |
| 10502001 |
Earth-boring tools carrying formation-engaging structures |
Juan Miguel Bilen, Steven Craig Russell, Kenneth R. Evans |
2019-12-10 |
| 10316589 |
Hybrid drill bit and design method |
Anton F. Zahradnik, Rudolf Carl Pessier, Matthew J. Meiners, Karlos B. Cepeda, 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, Karlos B. Cepeda, Michael S. Damschen +5 more |
2019-01-29 |
| 10072462 |
Hybrid drill bits |
Anton F. Zahradnik, Rudolf Carl Pessier, Mitchell A. Rothe, Karlos B. Cepeda, Michael S. Damschen +5 more |
2018-09-11 |
| 9782857 |
Hybrid drill bit having increased service life |
Carl E. Poteet, III, Eric C. Sullivan, John F. Bradford, Mark P. Blackman, Alan J. Massey +1 more |
2017-10-10 |
| 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, Karlos B. Cepeda, Michael S. Damschen +5 more |
2016-05-31 |
| 8978786 |
System and method for adjusting roller cone profile on hybrid bit |
Anton F. Zahradnik, Rudolf Carl Pessier, Mark P. Blackman, Robert Bradshaw, Scott Allan Young +4 more |
2015-03-17 |
| 8678111 |
Hybrid drill bit and design method |
Anton F. Zahradnik, Rudolf Carl Pessier, Matthew J. Meiners, Karlos B. Cepeda, 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, Tim Marvel, Matthew R. Isbell, Anton F. Zahradnik +3 more |
2013-01-22 |
| 8141664 |
Hybrid drill bit with high bearing pin angles |
Anton F. Zahradnik, Alan J. Massey |
2012-03-27 |
| 8028770 |
Conformal bearing for rock drill bit |
Aaron J. Dick, Chih Lin, Terry J. Koltermann, Anton F. Zahradnik, Daniel E. Scott +4 more |
2011-10-04 |
| 7975779 |
Threaded cone retention system for roller cone bits |
Anton F. Zahradnik, Eric C. Sullivan, Terry J. Koltermann, Aaron J. Dick, Scott Shiqiang Shu |
2011-07-12 |
| 7905301 |
Earth boring drill bits made from a low-carbon, high-molybdenum alloy |
Carmel Zouheir El Hakam, Eric C. Sullivan, John F. Bradford |
2011-03-15 |
| 7861805 |
Conformal bearing for rock drill bit |
Aaron J. Dick, Chih Lin, Terry J. Kolterman, Anton F. Zahradnik, Dan E. Scott +4 more |
2011-01-04 |
| 7845435 |
Hybrid drill bit and method of drilling |
Anton F. Zahradnik, Rudolf Carl Pessier, Michael S. Damschen, Karlos B. Cepeda, 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, Michael S. Damschen, Karlos B. Cepeda, Tim Marvel +1 more |
2010-11-30 |
| 7819208 |
Dynamically stable hybrid drill bit |
Rudolf Carl Pessier, Michael S. Damschen, Michael L. Doster |
2010-10-26 |
| 7708090 |
Excluder ring for earth-boring bit |
Anton F. Zahradnik, Gregory L. Ricks, Gregory W. Peterson, Chih Lin, Terry J. Koltermann |
2010-05-04 |
| 7628230 |
Wide groove roller cone bit |
Rudolf Carl Pessier, James L. Overstreet, Robert J. Buske |
2009-12-08 |
| 7413037 |
Metal face seal for an earth-boring bit |
Chih Lin, Gregory L. Ricks, Terry J. Koltermann |
2008-08-19 |
| 7392862 |
Seal insert ring for roller cone bits |
Anton F. Zahradnik, Ronny D. McCormick, Terry J. Koltermann, Michael J. Veasey |
2008-07-01 |