|
| US3976149 | 30 Ene 1975 | 24 Ago 1976 | Linden-Alimak AB | Rock drill equipment having a mechanized drill bit exchange |
| US4053182 | 5 Oct 1976 | 11 Oct 1977 | Ray M. Baughman | Mining method and apparatus |
| US4062412 | 29 Ene 1976 | 13 Dic 1977 | The United States of America as represented by the Secretary of the Interior | Flexible shaft drilling system |
| US4600061 | 8 Jun 1984 | 15 Jul 1986 | Methane Drainage Ventures | In-shaft drilling method for recovery of gas from subterranean formations |
| US4624328 | 6 Sep 1985 | 25 Nov 1986 | Methane Drainage Ventures | In-shaft drilling apparatus for recovery of gas from subterranean formations |
| US4691788 | 3 Jul 1985 | 8 Sep 1987 | Hitachi Construction Machinery Co., Ltd. Tokyo Gas Co., Ltd. | Lateral hole boring method and apparatus |
| US5553680 | 31 Ene 1995 | 10 Sep 1996 | | Horizontal drilling apparatus |
| US6571867 | 14 Jun 2001 | 3 Jun 2003 | | Apparatus for increasing the effective diameter of a wellbore |
| US7631708 | 31 Oct 2006 | 15 Dic 2009 | | Method and apparatus for horizontal drilling and oil recovery |
| USRE38616 | 4 Sep 2001 | 12 Oct 2004 | Halliburton Energy Services, Inc. | Downhole equipment, tools and assembly procedures for the drilling, tie-in and completion of vertical cased oil wells connected to liner-equipped multiple drainholes |