|
| US3999619 | 30 May 1975 | 28 Dic 1976 | Watson, Incorporated | Core barrel |
| US3999620 | 29 Mar 1976 | 28 Dic 1976 | Watson, Incorporated | Core barrel |
| US4768588 | 16 Dic 1986 | 6 Sep 1988 | | Connector assembly for a milling tool |
| US4925344 | 3 Ene 1989 | 15 May 1990 | | Method and apparatus for replacing buried pipe |
| US6170576 | 25 Feb 1999 | 9 Ene 2001 | Weatherford/Lamb, Inc. | Mills for wellbore operations |
| US6889781 | 3 Jul 2002 | 10 May 2005 | Performance Research & Drilling, LLC | Horizontal directional drilling in wells |
| US6964303 | 3 Jul 2002 | 15 Nov 2005 | Performance Research & Drilling, LLC | Horizontal directional drilling in wells |
